U.S. patent application number 16/992333 was filed with the patent office on 2020-11-26 for session establishment method and device.
The applicant listed for this patent is HUAWEI TECHNOLOGIES CO., LTD.. Invention is credited to Cuili GE, Yanmei YANG.
Application Number | 20200374352 16/992333 |
Document ID | / |
Family ID | 1000005031938 |
Filed Date | 2020-11-26 |
![](/patent/app/20200374352/US20200374352A1-20201126-D00000.png)
![](/patent/app/20200374352/US20200374352A1-20201126-D00001.png)
![](/patent/app/20200374352/US20200374352A1-20201126-D00002.png)
![](/patent/app/20200374352/US20200374352A1-20201126-D00003.png)
![](/patent/app/20200374352/US20200374352A1-20201126-D00004.png)
![](/patent/app/20200374352/US20200374352A1-20201126-D00005.png)
![](/patent/app/20200374352/US20200374352A1-20201126-D00006.png)
![](/patent/app/20200374352/US20200374352A1-20201126-D00007.png)
![](/patent/app/20200374352/US20200374352A1-20201126-D00008.png)
![](/patent/app/20200374352/US20200374352A1-20201126-D00009.png)
![](/patent/app/20200374352/US20200374352A1-20201126-D00010.png)
View All Diagrams
United States Patent
Application |
20200374352 |
Kind Code |
A1 |
GE; Cuili ; et al. |
November 26, 2020 |
SESSION ESTABLISHMENT METHOD AND DEVICE
Abstract
This specification provides a session establishment method and
device. The method includes: sending, by an SMF entity, a PDU
session establishment request message to a terminal, where the PDU
session establishment request message is used to request to
establish a PDU session; and receiving, by the SMF entity, a PDU
session establishment response message from the terminal. A method
for actively initiating a PDU session establishment procedure on a
network side is provided.
Inventors: |
GE; Cuili; (Beijing, CN)
; YANG; Yanmei; (Beijing, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HUAWEI TECHNOLOGIES CO., LTD. |
Shenzhen |
|
CN |
|
|
Family ID: |
1000005031938 |
Appl. No.: |
16/992333 |
Filed: |
August 13, 2020 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
PCT/CN2019/071303 |
Jan 11, 2019 |
|
|
|
16992333 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04L 12/18 20130101;
H04L 67/141 20130101; H04L 67/146 20130101; H04L 65/80
20130101 |
International
Class: |
H04L 29/08 20060101
H04L029/08; H04L 12/18 20060101 H04L012/18; H04L 29/06 20060101
H04L029/06 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 14, 2018 |
CN |
201810152310.3 |
Claims
1. A session establishment method, comprising: sending, by a
session management function (SMF) entity, a packet data unit (PDU)
session establishment request message to a terminal, wherein the
PDU session establishment request message is used to request to
establish a PDU session; and receiving, by the SMF entity, a PDU
session establishment response message from the terminal.
2. The method according to claim 1, wherein the PDU session
establishment response message comprises a session identifier of
the PDU session, or the method further comprises: receiving, by the
SMF entity, a session identifier of the PDU session from the
terminal.
3. The method according to claim 1, wherein the PDU session
establishment request message comprises session establishment
assistance information of the PDU session; or the method further
comprises: sending, by the SMF entity, session establishment
assistance information of the PDU session to the terminal, wherein
the session establishment assistance information of the PDU session
comprises one or more of a broadcast session identifier and a group
identifier, the broadcast session identifier is used to represent a
broadcast session in which the terminal participates, and the group
identifier is used to represent a group comprising the
terminal.
4. The method according to claim 3, wherein the method further
comprises: selecting, by the SMF entity based on the broadcast
session identifier, a user plane function (UPF) entity
corresponding to the broadcast session, and sending a user plane
session request to the UPF entity corresponding to the broadcast
session; or selecting, by the SMF entity based on the group
identifier, a UPF entity corresponding to the group identifier, and
sending a user plane session request to the UPF entity
corresponding to the group identifier, wherein the user plane
session request comprises user plane forwarding rule information of
the PDU session.
5. A session establishment method, comprising: receiving, by a
terminal, a packet data unit (PDU) session establishment request
message from a session management function (SMF) entity, wherein
the PDU session establishment request message is used to request to
establish a PDU session; and sending, by the terminal, a PDU
session establishment response message to the SMF entity based on
the PDU session establishment request message.
6. The method according to claim 5, wherein the PDU session
establishment response message comprises a session identifier of
the PDU session; or the method further comprises: sending, by the
terminal, a session identifier of the PDU session to the SMF
entity.
7. The method according to claim 5, wherein the PDU session
establishment request message comprises session establishment
assistance information of the PDU session, and the method further
comprises: obtaining, by the terminal based on the session
establishment assistance information of the PDU session,
information about a quality of service flow (QoS) flow
corresponding to the PDU session; or the method further comprises:
receiving, by the terminal, session establishment assistance
information of the PDU session from the SMF entity, and obtaining,
based on the session establishment assistance information of the
PDU session, information about a QoS flow corresponding to the PDU
session, wherein the session establishment assistance information
of the PDU session comprises one or more of a broadcast session
identifier and a group identifier, the broadcast session identifier
is used to represent a broadcast session in which the terminal
participates, and the group identifier is used to represent a group
comprising the terminal.
8. The method according to claim 5, wherein the PDU session
establishment request message comprises the session identifier of
the PDU session.
9. An apparatus comprising: a non-transitory memory storage
comprising instructions; and one or more processors in
communication with the memory storage, wherein the one or more
processors execute the instructions to: send a packet data unit
(PDU) session establishment request message to a terminal, wherein
the PDU session establishment request message is used to request to
establish a PDU session; and receive a PDU session establishment
response message from the terminal.
10. The apparatus according to claim 9, wherein the PDU session
establishment response message comprises a session identifier of
the PDU session, or the one or more processors are further
configured to: receive a session identifier of the PDU session from
the terminal.
11. The apparatus according to claim 9, wherein the PDU session
establishment request message comprises session establishment
assistance information of the PDU session; or the one or more
processors are further configured to: send session establishment
assistance information of the PDU session to the terminal, wherein
the session establishment assistance information of the PDU session
comprises one or more of a broadcast session identifier and a group
identifier, the broadcast session identifier is used to represent a
broadcast session in which the terminal participates, and the group
identifier is used to represent a group comprising the
terminal.
12. The apparatus according to claim 11, wherein the one or more
processors are further configured to: select, based on the
broadcast session identifier, a user plane function (UPF) entity
corresponding to the broadcast session, and send a user plane
session request to the UPF entity corresponding to the broadcast
session; or select, based on the group identifier, a UPF entity
corresponding to the group identifier, and send a user plane
session request to the UPF entity corresponding to the group
identifier, wherein the user plane session request comprises user
plane forwarding rule information of the PDU session.
13. An apparatus comprising: a non-transitory memory storage
comprising instructions; and one or more processors in
communication with the memory storage, wherein the one or more
processors execute the instructions to: receive a packet data unit
(PDU) session establishment request message from a session
management function (SMF) entity, wherein the PDU session
establishment request message is used to request to establish a PDU
session; and send a PDU session establishment response message to
the SMF entity based on the PDU session establishment request
message.
14. The apparatus according to claim 13, wherein the PDU session
establishment response message comprises a session identifier of
the PDU session; or the one or more processors are further
configured to: send a session identifier of the PDU session to the
SMF entity.
15. The apparatus according to claim 13, wherein the PDU session
establishment request message comprises session establishment
assistance information of the PDU session, and the one or more
processors are further configured to: obtain, based on the session
establishment assistance information of the PDU session,
information about a quality of service flow (QoS) flow
corresponding to the PDU session; or the one or more processors are
further configured to: receive session establishment assistance
information of the PDU session from the SMF entity, and obtain,
based on the session establishment assistance information of the
PDU session, information about a QoS flow corresponding to the PDU
session, wherein the session establishment assistance information
of the PDU session comprises one or more of a broadcast session
identifier and a group identifier, the broadcast session identifier
is used to represent a broadcast session in which a terminal
participates, and the group identifier is used to represent a group
comprising the terminal.
16. The apparatus according to claim 13, wherein the PDU session
establishment request message comprises the session identifier of
the PDU session.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of International
Application No. PCT/CN2019/071303, filed on Jan. 11, 2019, which
claims priority to Chinese Patent Application No. 201810152310.3,
filed on Feb. 14, 2018. The disclosures of the aforementioned
applications are hereby incorporated by reference in their
entireties.
TECHNICAL FIELD
[0002] This application relates to communications technologies, and
in particular, to a session establishment method and device.
BACKGROUND
[0003] With continuous development of communications technologies,
research and standardization for a fifth generation
(5th-generation, 5G) mobile communications technology have been
launched. There are logical function entities of different network
units in a 5G network, and the entities may perform different
network functions. In the 5G network, a broadcast path and a
unicast path may be established between a terminal and the network
by establishing a broadcast session or a unicast session between
the entities and the terminal, so that the broadcast path or the
unicast path is used for data exchange between the terminal and a
data network.
[0004] In the prior art, when a terminal receives data through a
broadcast path, when signal quality of data received through the
broadcast path is relatively poor, a downlink data receive mode of
the terminal needs to be switched from broadcast path transmission
to unicast path transmission. Alternatively, when signal quality of
data received through the broadcast path by most terminals on a
network side is relatively poor, the network side needs to switch,
from broadcast path transmission to unicast path transmission, all
terminals that receive data through the broadcast path on the
network side.
[0005] However, in the 5G network, how to quickly initiate a
unicast session and establish a unicast transmission path in a
timely manner, to quickly switch downlink data for the terminal
from a broadcast path to a unicast path is a problem that needs to
be resolved.
SUMMARY
[0006] This application provides a session establishment method and
device, to resolve a problem of how to trigger a unicast session
establishment procedure, to switch a terminal from a broadcast path
to a unicast path for receiving data.
[0007] According to a first aspect, this application provides a
session establishment method, including:
[0008] sending, by a session management function SMF entity, a
packet data unit PDU session establishment request message to a
terminal, where the PDU session establishment request message is
used to request to establish a PDU session; and
[0009] receiving, by the SMF entity, a PDU session establishment
response message from the terminal.
[0010] In the solution of this application, a method for actively
initiating a PDU session establishment procedure on a network side
is provided. When the terminal needs to be switched from a
broadcast path to a unicast path, the PDU session may be
established for the terminal on the network side, to establish the
unicast path. In addition, because it can be ensured that a same
UPF entity is selected by a broadcast session for the broadcast
path and is selected by a unicast session for the unicast path on
the network side, it can be ensured that user plane data is
consistent and synchronized on the broadcast path and the unicast
path when the user plane data is switched from the broadcast path
to the unicast path. Negotiation performed when user plane downlink
data is switched from the broadcast path to the unicast path is
avoided, so that a delay of switching from the broadcast path to
the unicast path can be reduced, to ensure fast and continuous
switching of data, and ensure fast switching that meets service
continuity requirements of a broadcast mode and a unicast mode. In
addition, the network side triggers the terminal to establish the
PDU session, and this can reduce signaling interaction in a process
in which the terminal establishes the PDU session with the network
side, and further reduce a delay.
[0011] With reference to the first aspect, in a first
implementation of the first aspect, the PDU session establishment
response message includes a session identifier of the PDU session;
or
[0012] the method further includes: receiving, by the SMF entity, a
session identifier of the PDU session from the terminal.
[0013] With reference to the first aspect or the first
implementation of the first aspect, in a second implementation of
the first aspect, the PDU session establishment request message
includes session establishment assistance information of the PDU
session; or
[0014] the method further includes: sending, by the SMF entity,
session establishment assistance information of the PDU session to
the terminal, where
[0015] the session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0016] With reference to the second implementation of the first
aspect, in a third implementation of the first aspect, the method
further includes: selecting, by the SMF entity based on the
broadcast session identifier, a user plane function UPF entity
corresponding to the broadcast session, and sending a user plane
session request to the UPF entity corresponding to the broadcast
session; or
[0017] selecting, by the SMF entity based on the group identifier,
a UPF entity corresponding to the group identifier, and sending a
user plane session request to the UPF entity corresponding to the
group identifier, where
[0018] the user plane session request includes user plane
forwarding rule information of the PDU session.
[0019] With reference to any one of the first aspect or the
implementations of the first aspect, in a fourth implementation of
the first aspect, the PDU session establishment request message
includes the session identifier of the PDU session, and the method
further includes: allocating, by the SMF entity, a session
identifier to the PDU session.
[0020] According to a second aspect, this application provides a
session establishment method, including:
[0021] receiving, by a session management function SMF entity, a
broadcast quality report message from a terminal, where the
broadcast quality report message is used to request to establish a
packet data unit PDU session; and
[0022] performing, by the SMF entity, a PDU session establishment
procedure based on the broadcast quality report message.
[0023] In the solution of this application, the broadcast quality
report message reported by the terminal is used to request to
establish the PDU session, and then the SMF entity may directly
perform the PDU session establishment procedure. In this way, a
process in which the terminal reports the broadcast quality report
message to the SMF entity, the SMF entity sends a PDU session
establishment request message to the terminal, and then the
terminal performs a PDU session establishment procedure is not
required, or a process in which an application server sends a
device trigger message to the terminal, and then the terminal
actively initiates a PDU session establishment procedure is not
required. These complex signaling interaction procedures are not
required. Therefore, signaling interaction between the terminal and
a network side can be reduced, a delay of switching from the
broadcast path to the unicast path can be reduced, and the PDU
session can be quickly established.
[0024] With reference to the second aspect, in a first
implementation of the second aspect, the broadcast quality report
message includes one or more of the following information: an
identifier of the broadcast quality report message, a PDU session
establishment request message, indication information, and a
session identifier; and
[0025] the indication information is used to request to establish
the PDU session, the session identifier is used to identify the PDU
session, and the PDU session establishment request message is used
to request to establish the PDU session.
[0026] With reference to the second aspect or the first
implementation of the second aspect, in a second implementation of
the second aspect, the broadcast quality report message includes
the PDU session establishment request message, and the method
further includes:
[0027] sending, by the SMF entity, a PDU session establishment
response message to the terminal.
[0028] With reference to the second implementation of the second
aspect, in a third implementation of the second aspect, the PDU
session establishment response message includes information about a
quality of service flow QoS flow corresponding to the PDU
session.
[0029] With reference to any one of the second aspect or the
implementations of the second aspect, in a fourth implementation of
the second aspect, the method further includes:
[0030] sending, by the SMF entity to the terminal based on the
broadcast quality report message, the information about the QoS
flow corresponding to the PDU session.
[0031] With reference to any one of the second aspect or the
implementations of the second aspect, in a fifth implementation of
the second aspect, the performing, by the SMF entity, a PDU session
establishment procedure based on the broadcast quality report
message includes:
[0032] performing, by the SMF entity, the PDU session establishment
procedure when the SMF entity determines, based on broadcast
received quality information in the broadcast quality report
message, that the terminal fails to receive data.
[0033] According to a third aspect, this application provides a
session establishment method, including:
[0034] receiving, by a terminal, a packet data unit PDU session
establishment request message from a session management function
SMF entity, where the PDU session establishment request message is
used to request to establish a PDU session; and
[0035] sending, by the terminal, a PDU session establishment
response message to the SMF entity based on the PDU session
establishment request message.
[0036] In the solution of this application, a method for actively
initiating a PDU session establishment procedure on a network side
is provided. When the terminal needs to be switched from a
broadcast path to a unicast path, the PDU session may be
established for the terminal on the network side, to establish the
unicast path. In addition, because it can be ensured that a same
UPF entity is selected by a broadcast session for the broadcast
path and is selected by a unicast session for the unicast path on
the network side, it can be ensured that user plane data is
consistent and synchronized on the broadcast path and the unicast
path when the user plane data is switched from the broadcast path
to the unicast path. Negotiation performed when user plane downlink
data is switched from the broadcast path to the unicast path is
avoided, so that a delay of switching from the broadcast path to
the unicast path can be reduced, to ensure fast and continuous
switching of data, and ensure fast switching that meets service
continuity requirements of a broadcast mode and a unicast mode. In
addition, the network side triggers the terminal to establish the
PDU session, and this can reduce signaling interaction in a process
in which the terminal establishes the PDU session with the network
side, and further reduce a delay.
[0037] With reference to the third aspect, in a first
implementation of the third aspect, the PDU session establishment
response message includes a session identifier of the PDU session;
or
[0038] the method further includes: sending, by the terminal, a
session identifier of the PDU session to the SMF entity.
[0039] With reference to the third aspect or the first
implementation of the third aspect, in a second implementation of
the third aspect, the PDU session establishment request message
includes session establishment assistance information of the PDU
session, and the method further includes: obtaining, by the
terminal based on the session establishment assistance information
of the PDU session, information about a quality of service flow QoS
flow corresponding to the PDU session; or
[0040] the method further includes: receiving, by the terminal,
session establishment assistance information of the PDU session
from the SMF entity, and obtaining, based on the session
establishment assistance information of the PDU session,
information about a QoS flow corresponding to the PDU session,
where
[0041] the session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0042] With reference to the third aspect or any implementation of
the third aspect, in a third implementation of the third aspect,
the PDU session establishment request message includes the session
identifier of the PDU session.
[0043] With reference to any one of the third aspect or the
implementations of the third aspect, in a fourth implementation of
the third aspect, the method further includes:
[0044] allocating, by the terminal, the session identifier to the
PDU session based on the PDU session establishment request
message.
[0045] According to a fourth aspect, this application provides a
session establishment method, including:
[0046] sending, by a terminal, a broadcast quality report message
to a session management function SMF entity, where the broadcast
quality report message is used to request to establish a packet
data unit PDU session.
[0047] In the solution of this application, the broadcast quality
report message reported by the terminal is used to request to
establish the PDU session, and then the SMF entity may directly
perform the PDU session establishment procedure. In this way, a
process in which the terminal reports the broadcast quality report
message to the SMF entity, the SMF entity sends a PDU session
establishment request message to the terminal, and then the
terminal performs a PDU session establishment procedure is not
required, or a process in which an application server sends a
device trigger message to the terminal, and then the terminal
actively initiates the PDU session establishment procedure is not
required. These complex signaling interaction procedures are not
required. Therefore, signaling interaction between the terminal and
a network side can be reduced, a delay of switching from the
broadcast path to the unicast path can be reduced, and the PDU
session can be quickly established.
[0048] With reference to the fourth aspect, in a first
implementation of the fourth aspect, the broadcast quality report
message includes one or more of the following information: an
identifier of the broadcast quality report message, a PDU session
establishment request message, indication information, and a PDU
session identifier; and
[0049] the indication information is used to request to establish
the PDU session, the session identifier is used to identify the PDU
session, and the PDU session establishment request message is used
to request to establish the PDU session.
[0050] With reference to the fourth aspect or the first
implementation of the fourth aspect, in a second implementation of
the fourth aspect, the method further includes:
[0051] receiving, by the terminal from the SMF entity, information
about a quality of service flow QoS flow corresponding to the PDU
session.
[0052] With reference to the fourth aspect or the first
implementation of the fourth aspect, in a third implementation of
the fourth aspect, the broadcast quality report message includes
the PDU session establishment request message, and the method
further includes:
[0053] receiving, by the terminal, a PDU session establishment
response message from the SMF entity.
[0054] With reference to the third implementation of the fourth
aspect, in a fourth implementation of the fourth aspect, the PDU
session establishment response message includes information about a
QoS flow corresponding to the PDU session.
[0055] With reference to any one of the fourth aspect or the
implementations of the fourth aspect, in a fifth implementation of
the fourth aspect, the sending, by a terminal, a broadcast quality
report message to an SMF entity includes:
[0056] sending the broadcast quality report message to the SMF
entity when the terminal fails to receive data.
[0057] According to a fifth aspect, this application provides a
session establishment method, including:
[0058] receiving, by an access and mobility management function AMF
entity, a packet data unit PDU session request message from a
session management function SMF entity, where the PDU session
establishment request message is used to request to establish a PDU
session;
[0059] sending, by the AMF entity, the PDU session request message
to a terminal; and
[0060] receiving, by the AMF entity, a PDU session establishment
response message from the terminal, and sending the PDU session
establishment response message to the SMF entity.
[0061] In the solution of this application, a method for actively
initiating a PDU session establishment procedure on a network side
is provided. When the terminal needs to be switched from a
broadcast path to a unicast path, the PDU session may be
established for the terminal on the network side, to establish the
unicast path. In addition, because it can be ensured that a same
UPF entity is selected by a broadcast session for the broadcast
path and is selected by a unicast session for the unicast path on
the network side, it can be ensured that user plane data is
consistent and synchronized on the broadcast path and the unicast
path when the user plane data is switched from the broadcast path
to the unicast path. Negotiation performed when user plane downlink
data is switched from the broadcast path to the unicast path is
avoided, so that a delay of switching from the broadcast path to
the unicast path can be reduced, to ensure fast and continuous
switching of data, and ensure fast switching that meets service
continuity requirements of a broadcast mode and a unicast mode. In
addition, the network side triggers the terminal to establish the
PDU session, and this can reduce signaling interaction in a process
in which the terminal establishes the PDU session with the network
side, and further reduce a delay.
[0062] With reference to the fifth aspect, in a first
implementation of the fifth aspect, the PDU session establishment
request message includes session establishment assistance
information of the PDU session; or
[0063] the method further includes: receiving, by the AMF entity,
session establishment assistance information of the PDU session
from the SMF entity, where
[0064] the session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0065] With reference to the first implementation of the fifth
aspect, in a second implementation of the fifth aspect, the
sending, by the AMF entity, the PDU session request message to a
terminal includes:
[0066] selecting, by the AMF entity, a radio access network
function RAN entity based on the session establishment assistance
information of the PDU session; and
[0067] sending, by the AMF entity, the PDU session request message
to the terminal through the RAN entity.
[0068] With reference to the fifth aspect, in a third
implementation of the fifth aspect, the PDU session request message
includes an identifier of the terminal; or
[0069] the method further includes: receiving, by the AMF entity,
an identifier of the terminal from the SMF entity.
[0070] With reference to the third implementation of the fifth
aspect, in a fourth implementation of the fifth aspect, the
sending, by the AMF entity, the PDU session request message to a
terminal includes:
[0071] selecting, by the AMF entity, a RAN entity based on the
identifier of the terminal; and
[0072] sending, by the AMF entity, the PDU session request message
to the terminal through the RAN entity.
[0073] According to a sixth aspect, this application provides a
session establishment device, including:
[0074] a first sending module, configured to send a packet data
unit PDU session establishment request message to a terminal, where
the PDU session establishment request message is used to request to
establish a PDU session; and
[0075] a first receiving module, configured to receive a PDU
session establishment response message from the terminal.
[0076] With reference to the sixth aspect, in a first
implementation of the sixth aspect, the PDU session establishment
response message includes a session identifier of the PDU session;
or
[0077] the device further includes a second receiving module,
configured to receive a session identifier of the PDU session from
the terminal.
[0078] With reference to the sixth aspect or the first
implementation of the sixth aspect, in a second implementation of
the sixth aspect, the PDU session establishment request message
includes session establishment assistance information of the PDU
session; or
[0079] the device further includes a second sending module,
configured to send session establishment assistance information of
the PDU session to the terminal, where
[0080] the session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0081] With reference to the second implementation of the sixth
aspect, in a third implementation of the sixth aspect, the device
further includes:
[0082] a first selection module, configured to: select, based on
the broadcast session identifier, a user plane function UPF entity
corresponding to the broadcast session, and send a user plane
session request to the UPF entity corresponding to the broadcast
session; or
[0083] a second selection module, configured to: select, based on
the group identifier, a UPF entity corresponding to the group
identifier, and send a user plane session request to the UPF entity
corresponding to the group identifier, where
[0084] the user plane session request includes user plane
forwarding rule information of the PDU session.
[0085] With reference to the sixth aspect or any implementation of
the sixth aspect, in a fourth implementation of the sixth aspect,
the PDU session establishment request message includes the session
identifier of the PDU session; and
[0086] the device further includes an allocation module, configured
to allocate the session identifier to the PDU session.
[0087] According to a seventh aspect, this application provides a
session establishment device, including:
[0088] a receiving module, configured to receive a broadcast
quality report message from a terminal, where the broadcast quality
report message is used to request to establish a packet data unit
PDU session; and
[0089] an execution module, configured to perform a PDU session
establishment procedure based on the broadcast quality report
message.
[0090] With reference to the seventh aspect, in a first
implementation of the seventh aspect, the broadcast quality report
message includes one or more of the following information: an
identifier of the broadcast quality report message, a PDU session
establishment request message, indication information, and a
session identifier; and
[0091] the indication information is used to request to establish
the PDU session, the session identifier is used to identify the PDU
session, and the PDU session establishment request message is used
to request to establish the PDU session.
[0092] With reference to the seventh aspect or the first
implementation of the seventh aspect, in a second implementation of
the seventh aspect, the broadcast quality report message includes
the PDU session establishment request message, and the device
further includes:
[0093] a first sending module, configured to send a PDU session
establishment response message to the terminal.
[0094] With reference to the second implementation of the seventh
aspect, in a third implementation of the seventh aspect, the PDU
session establishment response message includes information about a
quality of service flow QoS flow corresponding to the PDU
session.
[0095] With reference to any one of the seventh aspect or the
implementations of the seventh aspect, in a fourth implementation
of the seventh aspect, the device further includes:
[0096] a second sending module, configured to send, to the terminal
based on the broadcast quality report message, the information
about the QoS flow corresponding to the PDU session.
[0097] With reference to any one of the seventh aspect or the
implementations of the seventh aspect, in a fifth implementation of
the seventh aspect, the execution module is specifically configured
to:
[0098] perform the PDU session establishment procedure when it is
determined, based on broadcast received quality information in the
broadcast quality report message, that the terminal fails to
receive data.
[0099] According to an eighth aspect, this application provides a
session establishment device, including:
[0100] a receiving module, configured to receive a packet data unit
PDU session establishment request message from a session management
function SMF entity, where the PDU session establishment request
message is used to request to establish a PDU session; and
[0101] a first sending module, configured to send a PDU session
establishment response message to the SMF entity based on the PDU
session establishment request message.
[0102] With reference to the eighth aspect, in a first
implementation of the eighth aspect, the PDU session establishment
response message includes a session identifier of the PDU session;
or
[0103] the device further includes a second sending module,
configured to send a session identifier of the PDU session to the
SMF entity.
[0104] With reference to the eighth aspect or the first
implementation of the eighth aspect, in a second implementation of
the eighth aspect, the PDU session establishment request message
includes session establishment assistance information of the PDU
session, and the device further includes: a first obtaining module,
configured to obtain, based on the session establishment assistance
information of the PDU session, information about a quality of
service flow QoS flow corresponding to the PDU session; or
[0105] the device further includes a second obtaining module,
configured to receive session establishment assistance information
of the PDU session from the SMF entity, and obtain, based on the
session establishment assistance information of the PDU session,
information about a QoS flow corresponding to the PDU session,
where
[0106] the session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0107] With reference to the eighth aspect or any implementation of
the eighth aspect, in a third implementation of the eighth aspect,
the PDU session establishment request message includes the session
identifier of the PDU session.
[0108] With reference to any one of the eighth aspect or the
implementations of the eighth aspect, in a fourth implementation of
the eighth aspect, the device further includes:
[0109] an allocation module, configured to allocate the session
identifier to the PDU session based on the PDU session
establishment request message.
[0110] According to a ninth aspect, this application provides a
session establishment device, including:
[0111] a sending module, configured to send a broadcast quality
report message to a session management function SMF entity, where
the broadcast quality report message is used to request to
establish a packet data unit PDU session.
[0112] With reference to the ninth aspect, in a first
implementation of the ninth aspect, the broadcast quality report
message includes one or more of the following information: an
identifier of the broadcast quality report message, a PDU session
establishment request message, indication information, and a PDU
session identifier; and
[0113] the indication information is used to request to establish
the PDU session, the session identifier is used to identify the PDU
session, and the PDU session establishment request message is used
to request to establish the PDU session.
[0114] With reference to any one of the ninth aspect or the
implementations of the ninth aspect, in a second implementation of
the ninth aspect, the device further includes:
[0115] a first receiving module, configured to receive, from the
SMF entity, information about a quality of service flow QoS flow
corresponding to the PDU session.
[0116] With reference to the ninth aspect or the first
implementation of the ninth aspect, in a third implementation of
the ninth aspect, the broadcast quality report message includes the
PDU session establishment request message, and the device further
includes:
[0117] a second receiving module, configured to receive a PDU
session establishment response message from the SMF entity.
[0118] With reference to the third implementation of the ninth
aspect, in a fourth implementation of the ninth aspect, the PDU
session establishment response message includes information about a
QoS flow corresponding to the PDU session.
[0119] With reference to any one of the ninth aspect or the
implementations of the ninth aspect, in a fifth implementation of
the ninth aspect, the sending module is specifically configured
to:
[0120] send the broadcast quality report message to the SMF entity
when it is determined that data fails to be received.
[0121] According to a tenth aspect, this application provides a
session establishment device, including:
[0122] a first receiving module, configured to receive a packet
data unit PDU session request message from a session management
function SMF entity, where the PDU session establishment request
message is used to request to establish a PDU session;
[0123] a first sending module, configured to send the PDU session
request message to a terminal;
[0124] a second receiving module, configured to receive a PDU
session establishment response message from the terminal; and
[0125] a second sending module, configured to send the PDU session
establishment response message to the SMF entity.
[0126] With reference to the fifth aspect, in a first
implementation of the fifth aspect, the PDU session establishment
request message includes session establishment assistance
information of the PDU session; or
[0127] the device further includes: a third receiving module,
configured to receive session establishment assistance information
of the PDU session from the SMF entity, where
[0128] the session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0129] With reference to the first implementation of the fifth
aspect, in a second implementation of the fifth aspect, the first
sending module includes:
[0130] a first selection submodule, configured to select a radio
access network function RAN entity based on the session
establishment assistance information of the PDU session; and
[0131] a first sending submodule, configured to send the PDU
session request message to the terminal through the RAN entity.
[0132] With reference to the fifth aspect, in a third
implementation of the fifth aspect, the PDU session request message
includes an identifier of the terminal; or
[0133] the device further includes a fourth receiving module,
configured to receive an identifier of the terminal from the SMF
entity.
[0134] With reference to the third implementation of the fifth
aspect, in a fourth implementation of the fifth aspect, the first
sending module includes:
[0135] a second selection submodule, configured to select a RAN
entity based on the identifier of the terminal; and
[0136] a second sending submodule, configured to send the PDU
session request message to the terminal through the RAN entity.
[0137] According to an eleventh aspect, a communications system is
provided, including the session establishment device according to
any implementation in the sixth aspect, the session establishment
device according to any implementation in the eighth aspect, and
the session establishment device according to any implementation in
the tenth aspect.
[0138] According to a twelfth aspect, a communications system is
provided, including the session establishment device according to
any implementation in the seventh aspect and the session
establishment device according to any implementation in the ninth
aspect.
[0139] According to a thirteenth aspect, an SMF entity is provided.
The SMF entity includes a unit or means (means) configured to
perform steps of any method according to the first aspect.
[0140] According to a fourteenth aspect, an SMF entity is provided.
The SMF entity includes a processor and a memory. The memory is
configured to store a computer program, and the processor invokes
the computer program stored in the memory to perform any method
according to the first aspect.
[0141] According to a fifteenth aspect, an SMF entity is provided.
The SMF entity includes at least one processor element or chip
configured to perform any method according to the first aspect.
[0142] According to a sixteenth aspect, a program is provided. A
processor executes the program to perform any method according to
the first aspect.
[0143] According to a seventeenth aspect, a computer readable
storage medium is provided, including the program according to the
sixteenth aspect.
[0144] According to an eighteenth aspect, an SMF entity is
provided. The SMF entity includes a unit or means (means)
configured to perform steps of any method according to the second
aspect.
[0145] According to a nineteenth aspect, an SMF entity is provided.
The SMF entity includes a processor and a memory. The memory is
configured to store a computer program, and the processor invokes
the computer program stored in the memory to perform any method
according to the second aspect.
[0146] According to a twentieth aspect, an SMF entity is provided.
The SMF entity includes at least one processor element or chip
configured to perform any method according to the second
aspect.
[0147] According to a twenty-first aspect, a program is provided. A
processor executes the program to perform any method according to
the second aspect.
[0148] According to a twenty-second aspect, a computer readable
storage medium is provided, including the program according to the
twenty-first aspect.
[0149] According to a twenty-third aspect, a terminal device is
provided. The terminal device includes a unit or means (means)
configured to perform steps of any method according to the third
aspect.
[0150] According to a twenty-fourth aspect, a terminal device is
provided. The terminal device includes a processor and a memory.
The memory is configured to store a computer program, and the
processor invokes the computer program stored in the memory to
perform any method according to the third aspect.
[0151] According to a twenty-fifth aspect, a terminal device is
provided. The terminal device includes at least one processor
element or chip configured to perform any method according to the
third aspect.
[0152] According to a twenty-sixth aspect, a program is provided. A
processor executes the program to perform any method according to
the third aspect.
[0153] According to a twenty-seventh aspect, a computer readable
storage medium is provided, including the program according to the
twenty-sixth aspect.
[0154] According to a twenty-eighth aspect, a terminal device is
provided. The terminal device includes a unit or means (means)
configured to perform steps of any method according to the fourth
aspect.
[0155] According to a twenty-ninth aspect, a terminal device is
provided. The terminal device includes a processor and a memory.
The memory is configured to store a computer program, and the
processor invokes the computer program stored in the memory to
perform any method according to the fourth aspect.
[0156] According to a thirtieth aspect, a terminal device is
provided. The terminal device includes at least one processor
element or chip configured to perform any method according to the
fourth aspect.
[0157] According to a thirty-first aspect, a program is provided. A
processor executes the program to perform any method according to
the fourth aspect.
[0158] According to a thirty-second aspect, a computer readable
storage medium is provided, including the program according to the
thirty-first aspect.
[0159] According to a thirty-third aspect, an AMF entity is
provided. The AMF entity includes a unit or means (means)
configured to perform steps of any method according to the fifth
aspect.
[0160] According to a thirty-fourth aspect, an AMF entity is
provided. The AMF entity includes a processor and a memory. The
memory is configured to store a computer program, and the processor
invokes the computer program stored in the memory to perform any
method according to the fifth aspect.
[0161] According to a thirty-fifth aspect, an AMF entity is
provided. The AMF entity includes at least one processor element or
chip configured to perform any method according to the fifth
aspect.
[0162] According to a thirty-sixth aspect, a program is provided. A
processor executes the program to perform any method according to
the fifth aspect.
[0163] According to a thirty-seventh aspect, a computer readable
storage medium is provided, including the program according to the
thirty-sixth aspect.
BRIEF DESCRIPTION OF DRAWINGS
[0164] FIG. 1 provides an architectural diagram 1 of a network
structure;
[0165] FIG. 2 provides an architectural diagram 2 of a network
structure;
[0166] FIG. 3A to FIG. 3C are a signaling diagram of a PDU session
establishment method according to the prior art;
[0167] FIG. 4 is a signaling diagram of a method for triggering PDU
session establishment according to the prior art;
[0168] FIG. 5 is a flowchart of a session establishment method
according to an embodiment of this application;
[0169] FIG. 6 is a flowchart of another session establishment
method according to an embodiment of this application;
[0170] FIG. 7 is a flowchart of still another session establishment
method according to an embodiment of this application;
[0171] FIG. 8A and FIG. 8B are a signaling diagram of yet another
session establishment method according to an embodiment of this
application;
[0172] FIG. 9A and FIG. 9B are a signaling diagram of still yet
another session establishment method according to an embodiment of
this application;
[0173] FIG. 10A and FIG. 10B are a signaling diagram of a further
session establishment method according to an embodiment of this
application;
[0174] FIG. 11 is a flowchart of a still further session
establishment method according to an embodiment of this
application;
[0175] FIG. 12 is a flowchart of a yet further session
establishment method according to an embodiment of this
application;
[0176] FIG. 13 is a signaling diagram of a still yet further
session establishment method according to an embodiment of this
application;
[0177] FIG. 14 is a signaling diagram of even yet another session
establishment method according to an embodiment of this
application;
[0178] FIG. 15 is a schematic structural diagram of a session
establishment device according to an embodiment of this
application;
[0179] FIG. 16 is a schematic structural diagram of another session
establishment device according to an embodiment of this
application;
[0180] FIG. 17 is a schematic structural diagram of still another
session establishment device according to an embodiment of this
application;
[0181] FIG. 18 is a schematic structural diagram of yet another
session establishment device according to an embodiment of this
application;
[0182] FIG. 19 is a schematic structural diagram of still yet
another session establishment device according to an embodiment of
this application;
[0183] FIG. 20 is a schematic structural diagram of a further
session establishment device according to an embodiment of this
application;
[0184] FIG. 21 is a schematic structural diagram of a still further
session establishment device according to an embodiment of this
application;
[0185] FIG. 22 is a schematic structural diagram of a yet further
session establishment device according to an embodiment of this
application;
[0186] FIG. 23 is a schematic structural diagram of a still yet
further session establishment device according to an embodiment of
this application;
[0187] FIG. 24 is a schematic structural diagram of even yet
another session establishment device according to an embodiment of
this application;
[0188] FIG. 25 is a schematic structural diagram of even yet
another session establishment device according to an embodiment of
this application;
[0189] FIG. 26 is a schematic structural diagram of even yet
another session establishment device according to an embodiment of
this application;
[0190] FIG. 27 is a schematic structural diagram of an SMF entity
according to an embodiment of this application;
[0191] FIG. 28 is a schematic structural diagram of a terminal
device according to an embodiment of this application;
[0192] FIG. 29 is a schematic structural diagram of an AMF entity
according to an embodiment of this application;
[0193] FIG. 30 is a schematic structural diagram of another SMF
entity according to an embodiment of this application; and
[0194] FIG. 31 is a schematic structural diagram of another
terminal device according to an embodiment of this application.
DESCRIPTION OF EMBODIMENTS
[0195] The embodiments of this application are applied to a 5G
communications system or another system that may emerge in the
future. The following describes some terms used in this
application, to facilitate understanding of a person skilled in the
art. It should be noted that, when solutions in the embodiments of
this application are applied to the 5G communications system or the
another system that may emerge in the future, names of a network
device and a terminal may change, but this does not affect
implementation of the solutions in the embodiments of this
application.
[0196] The following describes the technical solutions of the
embodiments in this application with reference to accompanying
drawings.
[0197] FIG. 1 provides an architectural diagram 1 of a network
structure, and FIG. 2 provides an architectural diagram 2 of a
network structure. The network structures may be applied to a
next-generation communications system. FIG. 1 is an architectural
diagram of a service-based 5G network architecture. Nnrf in FIG. 1
is a name of a service-based interface. A circle on each network
entity in FIG. 1 indicates that the network entity exposes an Nnrf
interface to another network entity. In addition, the network
entity provides a service for the another network entity through
the Nnrf interface, and the another network entity may obtain,
through the Nnrf interface, the service provided by the network
entity. FIG. 2 is an architectural diagram of an interface-based 5G
network architecture. As shown in FIG. 2, network entities
communicate with each other through interfaces in a next-generation
network architecture, and a terminal also communicates with a
network entity through an interface. N1, N2, N3, N4, N5, N6, N7,
N8, N9, N10, N11, N12, N13, N14, N15, and the like in FIG. 1 and
FIG. 2 are interfaces. A network entity may alternatively be
referred to as a network element, a network node, or a
communications node. The following briefly describes components in
the network structures shown in FIG. 1 and FIG. 2.
[0198] Mobile communications technologies are updated and upgraded,
and research and standardization for 5G technology have been
launched. The 5G technology may be applied to fields such as mobile
broadband, multimedia, machine type communication (machine type
communication, MTC), industrial control, and an intelligent
transportation system (intelligent transportation system, ITS). To
meet greatly changing service requirements, a 5G network needs to
be flexibly constructed. A flexible 5G construction manner is to
separate network functions. To be specific, a control plane
(control plane, CP) function and a user plane (user plane, UP)
function are separated, and a mobility management (mobility
management, MM) function and a session management (session
management, SM) function at a CP are separated. A network slicing
(network slice) technology may be used to separate the network
functions.
[0199] The network slicing technology may be used to divide a
physical network into a plurality of virtual end-to-end virtual
networks. Each divided virtual network, including a device, an
access technology, a transmission path, a core network, and the
like that are in the virtual network, is logically independent.
Each network slice includes one instance of an independent network
function or one instance of a function combination. Each network
slice has a different function feature, and faces a different
requirement and service. The network slices are separated from each
other, so that different users or user groups can flexibly and
dynamically customize a network capability based on different
application scenarios and requirements. A network slice is a
logical network, and the logical network may provide a specific
network function and a specific network feature for each network
entity in the network.
[0200] A network slice includes a control plane function (control
plane function, CPF) entity and a user plane function (user plane
function, UPF) entity. The CPF entity includes an access and
mobility management function (access and mobility management
function, AMF) entity and a session management function (session
management function, SMF) entity. The CPF entity mainly completes
functions such as access authentication, security encryption, and
location registration that are of a terminal, and completes
functions such as establishment, release, and modification of a
user plane transmission path. The UPF entity mainly completes
functions such as routing and forwarding of user plane data.
[0201] A terminal may include various handheld devices,
vehicle-mounted devices, wearable devices, or computing devices
that have a communication function, or another processing device
connected to a wireless modem, and terminals in various forms such
as a mobile station (mobile station, MS), a terminal (terminal),
user equipment (user equipment, UE), and a software terminal, for
example, a water meter, an electricity meter, and a sensor.
[0202] A radio access network (radio access network, RAN) is a
network including a plurality of 5G-RAN nodes, and implements a
radio physical layer function, resource scheduling and radio
resource management, radio access control, and a mobility
management function. For example, a 5G-RAN is connected to a UPF
entity through a user plane interface N3, to transmit data of a
terminal. The 5G-RAN establishes a control plane signaling
connection to an AMF entity through a control plane interface N2,
to implement functions such as radio access bearer control. The RAN
may alternatively be represented as an (R)AN.
[0203] An authentication credential repository and processing
function (authentication credential repository and processing
function, ARPF) entity is configured to generate a security vector
used for authentication between UE and a network, and may be used
as a part of a UDM entity.
[0204] An authentication server function (authentication server
function, AUSF) entity is a full-function node, and is configured
to: receive an authentication vector request from an AMF entity,
and return, to the AMF entity, a 5G authentication vector obtained
from an ARPF entity or a UDM entity; or further process a 5G
authentication vector obtained from an ARPF entity or a UDM entity,
and then return a processed 5G authentication vector to an AMF
entity, so that the 5G authentication vector is used for security
authentication between a terminal and a network side.
[0205] An AMF entity is responsible for authentication of a
terminal, mobility management of a terminal, network slice
selection, selection of an SMF entity, access authorization and
access authentication, a security-related function, and the like.
In addition, the AMF entity may serve as an anchor for connection
between an N1 interface and an N2 interface, and provide routing of
N1/N2 SM information for an SMF entity. In addition, the AMF entity
may maintain and manage status information of a terminal, and
participate in a broadcast session.
[0206] An SMF entity is responsible for a terminal session,
allocating and controlling a UPF entity, allocating and managing an
internet protocol (internet protocol, IP) address of a terminal,
managing quality of service (quality of service, QoS) of a session,
obtaining a policy control and charging (policy control and
charging, PCC) policy from a policy control function (policy
control function, PCF) entity, a termination of an SM part of a
non-access stratum (non-access stratum, NAS) message, notifying
downlink data, determining a session and service continuity
(session and service continuity, SSC) mode of a session, a roaming
function, and the like. In this application, the SMF entity may be
responsible for broadcast session management, including
establishment, update, and release of a broadcast session,
allocation of a broadcast session identifier, and the like. In this
application, the SMF entity may further receive broadcast received
quality information reported by a terminal, to complete switching
from broadcast transmission to unicast transmission.
[0207] A data network (data network, DN) provides an external data
network service.
[0208] A network exposure function (network exposure function, NEF)
entity is responsible for connecting an SMF entity and an external
DN network, and is configured to provide a secure method for
exposing a service and a capability of a 3.sup.rd generation
partnership project (3.sup.rd generation partnership project, 3GPP)
network, translate information exchanged between an application
function (application function, AF) entity and an internal network,
receive information from another network entity, and expose the
information to an internal network element or an application
service function network element.
[0209] A UPF entity serves as an anchor point for connecting to a
packet data unit (packet data unit, PDU) session (session), and is
responsible for filtering a data packet of a terminal, data
transmission and forwarding, rate control, charging information
generation, packet detection and policy application, transmission
usage reporting, user-plane QoS processing, uplink transmission
authentication, transmission grade verification, downlink data
packet buffering, downlink data notification triggering, a branch
point supporting a multi-homed (multi-homed) PDU session, and the
like.
[0210] A unified data management function (unified data management,
UDM) entity allocates reference information to a network entity,
for example, allocates reference information to an SMF entity or an
NEF entity.
[0211] A PCF entity allocates reference information to a network
entity, for example, allocates reference information to an SMF
entity or an NEF entity. In addition, the PCF supports a unified
policy architecture to control network behavior. The PCF may
provide, for a control plane function, a policy rule used by an
entity on the control plane function to execute, so that a front
end (front end) accesses subscription information related to policy
decision in a unified data repository (unified data repository,
UDR).
[0212] A network slice selection function (network slice selection
function, NSSF) entity is configured to select an appropriate
network slice for UE.
[0213] An AF entity is an application function, configured to
provide interaction between an external application and a PCF
entity of a core network, and is mainly configured to perform
policy and charging control on an IP-connectivity access network
(IP-connectivity access network, IP-CAN) corresponding to the
application, and may be further configured to access an NEF and
affect communication routing.
[0214] A network function repository function (NF repository
function, NRF) entity is further provided, and an NF is a network
function (network function, NF).
[0215] Identity (identity, ID): A VPLMN entity, an HPLMN entity, an
SMF entity, a terminal, and the like may have their own IDs.
[0216] A PDU session is a unicast session.
[0217] Path: A path designed in the embodiments of this application
is a transmission path, that meets a specific QoS requirement, of
user plane data from a network side to a user terminal, and
corresponds to a concept of a bearer (bearer) in a long-term
evolution (long-term evolution, LTE) system. A broadcast path is a
path on which user plane data is sent from a network side to UE
through broadcast transmission, and a unicast path is a path on
which user plane data is sent to the UE through unicast
transmission.
[0218] Broadcast means that a data source sends data to a plurality
of receivers, may alternatively be referred to as multicast, and
includes data distribution modes of 1:all and 1:n. The data
distribution mode 1:all indicates that a data source sends data to
all receivers, and the data distribution mode 1:n indicates that a
data source sends data to n receivers. Received downlink data is
sent through a broadcast channel between a base station and an air
interface.
[0219] It should be noted that the terms used in the embodiments of
this application may be mutually referenced, and details are not
described repeatedly.
[0220] The communications network entities may establish a
broadcast path in a specific network area or geographic area, to
broadcast service data to a terminal located in the network area or
geographic area, thereby improving utilization efficiency of
network transmission resources. As 3GPP technologies expand to
vertical fields, increasing service scenarios suitable for
broadcast/multicast are generated. For example, the service
scenarios suitable for broadcast/multicast include a group call
service, remote upgrade of an internet of things (internet of
things, IOT), and internet of vehicles broadcasting. Followed by
that is more diversified business models. In a multimedia
broadcast/multicast service (multimedia broadcast/multicast
service, MBMS), a terminal may perform a broadcast session. In this
case, the terminal may be in receive only mode (receive only mode),
or the terminal may be in receive only mode and have a separate
unicast connection. In a public land mobile network (public land
mobile network, PLMN), a terminal may perform a unicast session. In
this case, the terminal may be in receive only mode and have a
separate unicast connection. The terminal may scan a pre-broadcast
resource and read a system message. It can be known that, the
terminal may be configured to receive only a broadcast radio
resource, and does not need to subscribe to a PLMN operator server.
In this case, the terminal is applicable to receiving a television
(television) service. Alternatively, the terminal may subscribe to
a PLMN operator server, so that the terminal simultaneously
receives unicast data and broadcast data through a PLMN operator
network. The terminal may be configured to receive a specific
service or specific content.
[0221] In another scenario, a 5G network entity may support a group
mode, and the 5G network entity may learn of which terminals belong
to a same group. Usually, these groups may be groups created based
on a service type, or a geographic area, or a network area.
Further, terminals belonging to a same group generally have a same
physical location or a same service behavior. Each terminal in a
group may perform a broadcast session or a unicast session. The
group may be an internal group defined by a mobile communications
network, or may be an external group defined by a third-party
application. There may be a specific mapping relationship, for
example, a one-to-one mapping relationship, between an internal
group and an external group. The mapping relationship may be stored
in a UDM entity.
[0222] FIG. 3A to FIG. 3C are a signaling diagram of a PDU session
establishment method according to the prior art. As shown in FIG.
3A to FIG. 3C, the PDU session establishment method in the prior
art is specifically described as follows:
[0223] S11. A terminal sends a PDU session establishment request
message to an AMF entity.
[0224] Specifically, first, the terminal has registered with the
AMF entity, and the AMF entity has obtained subscription
information of a user from a UDM entity.
[0225] Then, the terminal generates a new PDU session identifier.
Then, the terminal sends the PDU session establishment request (PDU
session establishment request) message to the AMF entity. The PDU
session establishment request message is a NAS message. Then, the
terminal initiates a PDU session establishment procedure. The PDU
session establishment request message includes session
management-network slice selection assistance information (session
management-network slice selection assistance information, S-NSSAI)
corresponding to a PDU session, a data network name (data network
name, DNN) corresponding to the PDU session, a PDU session
identifier, a request type (request type), and N1 SM information
(N1 session management information). For example, a format of the
PDU session establishment request message is (S-NSSAI, DNN, PDU
session ID, request type, N1 SM information). The S-NSSAI is the
session management-network slice selection assistance information
corresponding to the PDU session, the DNN is the data network name
corresponding to the PDU session, the PDU session ID is the PDU
session identifier, the request type is the request type, and the
N1 SM information is the N1 SM information. The request type in the
PDU session establishment request message may be an initial request
type, an emergency request type, an existing session request type,
an existing emergency session request type, or the like. The N1 SM
information is session management information of an N1 reference
point. The reference point herein is a reference point between the
AMF entity and the terminal. The N1 SM information may include a
parameter of a session management PDU data network request
container (SM PDU DN request container), and the parameter includes
information used by an external DN to authorize a PDU session.
[0226] In addition, the PDU session establishment request message
may further include a PDU type (PDU type) and an SSC mode (mode).
The PDU type is a type of a packet data unit, for example, an
internet protocol version 4 (internet protocol version 4, IPv4), an
internet protocol version 6 (internet protocol version 4, IPv6), an
Ethernet (ethernet), and unstructured (unstructured). The SSC mode
represents session and service continuity. The SSC mode includes
three modes: a mode 1, a mode 2, and a mode 3. The mode 1 means
that a connection for the terminal is maintained on a network side,
and may be referred to as a persistent connection. The mode 2 is a
manner in which an original connection is disconnected and then a
new connection is established. The mode 3 is a manner in which a
new connection is established and then the original connection is
disconnected.
[0227] S12. The AMF entity selects an SMF entity.
[0228] Specifically, the AMF entity determines, based on the
request type and the PDU session ID in the PDU session
establishment request message, that the received PDU session
establishment request message indicates that the terminal is to
request a PDU session. Further, the AMF entity selects an SMF
entity according to a preset rule, and the AMF entity stores the
PDU session ID and an identifier of the selected SMF entity. The
identifier of the selected SMF entity may be represented as an SMF
ID. For a rule for selecting an SMF entity, refer to a rule in the
prior art.
[0229] S13. The AMF entity sends an SM request message to the SMF
entity.
[0230] Specifically, the AMF entity sends the SM request (SM
Request) message to the SMF entity. The SM request message includes
a subscriber permanent identifier (subscriber permanent ID), the
DNN, the S-NSSAI, the PDU session identifier, the N1 SM
information, user location information (user location information),
and an access technology type (access technology type). The access
technology type includes a 3GPP type and a non-3GPP type. For
example, a format of the SM request message is (subscriber
permanent ID, DNN, S-NSSAI, PDU session ID, AMF ID, N1 SM
information (PDU session ID, PDU session establishment request),
user location information, access technology type). The AMF ID
represents an identifier of the AMF entity.
[0231] S14a. The SMF entity sends a subscription data request
message to the UDM entity.
[0232] Specifically, if the SMF entity has not obtained SM-related
subscription information of the terminal from a DNN entity, the SMF
entity needs to send the subscription data request message to the
UDM entity to obtain the SM-related subscription information. The
subscription data request (subscription data request) message
includes the subscriber permanent ID (subscriber permanent ID) and
the DNN. For example, a format of the subscription data request
message is (subscriber permanent ID, DNN).
[0233] S14b. The UDM entity sends subscription information to the
SMF entity.
[0234] Specifically, the UDM entity sends a subscription data
response (subscription data response) message to the SMF entity.
The subscription data response message includes the subscription
information, and the subscription information includes, for
example, an authorized PDU type, an authorized SSC mode, and a
default QoS profile (default QoS profile). Then, the SMF entity
performs an authorization check on the subscription information. If
the SMF entity determines that the authorization check fails, the
SMF entity sends NAS signaling to the terminal. The NAS signaling
indicates that a session establishment request of the terminal is
rejected.
[0235] S15. The SMF entity completes authorization/authentication
for PDU session establishment.
[0236] Specifically, if the SMF entity needs to
authorize/authenticate the PDU session establishment, the SMF
entity needs to first select a UPF entity according to a rule, and
then the SMF entity triggers the authorization/authentication for
the PDU session establishment, to complete the
authorization/authentication for the PDU session establishment. For
a rule for selecting an UPF entity, refer to a rule in the prior
art.
[0237] S16a. The SMF entity selects a PCF entity according to a
rule.
[0238] Specifically, if a dynamic PCC needs to be deployed, the SMF
entity needs to select a PCF entity according to the rule. For a
rule for selecting a PCF entity, refer to a rule in the prior
art.
[0239] S16b. The SMF entity obtains a PCC rule.
[0240] Specifically, the SMF entity sends a PDU-controller area
network (controller area network, CAN) session establishment
request (PDU-CAN Session Establishment) to the selected PCF entity,
to obtain a PCC rule corresponding to the PDU session.
[0241] S17. The SMF entity selects a UPF entity.
[0242] Specifically, if step S15 is not performed, in this step,
the SMF entity selects a UPF entity, and the SMF entity selects an
SSC mode.
[0243] S18. The SMF entity initiates a PDU-CAN session
establishment procedure.
[0244] Specifically, if a dynamic PCC is deployed, and a PDU-CAN
session is not established, the SMF entity initiates the PDU-CAN
session establishment procedure to the PCF entity, and then the SMF
entity obtains a default PCC rule from the PCF entity. If the
request type sent by the terminal indicates that a PDU session
exists, the SMF entity initiates PDU-CAN session modification, and
the SMF entity sends an allocated IP address of the terminal to the
PCF entity.
[0245] S19a. The SMF entity initiates an N4 session
establishment/modification procedure to the UPF entity.
[0246] Specifically, if the request type is the initial request
type, the SMF entity sends an N4 session establishment message to
the UPF entity; otherwise, the SMF entity sends an N4 session
modification message to the UPF entity. The SMF entity provides
packet detection, a report rule, and CN tunnel information (CN
tunnel info) for the UPF entity.
[0247] S19b. The UPF entity sends an N4 session
establishment/modification response message to the SMF entity,
where the N4 session establishment/modification response message
may include the CN tunnel information.
[0248] S110. The SMF entity sends an SM response message to the AMF
entity.
[0249] Specifically, the SM response (SM response) message includes
a cause value (cause), N2 reference point session management
information (N2 SM information), and N1 SM information. The IPv4
address herein is an IPv4 address allocated by the SMF entity. A
reference point in the N2 reference point session management
information is a reference point between the AMF entity and the SMF
entity. The N2 reference point session management information
includes the PDU session identifier, the QoS profile (QoS
Profile(s)), and the CN tunnel information. The N1 SM information
includes a PDU session establishment accept (PDU session
establishment accept) message, and the PDU session establishment
accept message includes an authorized quality of service rule
(authorized QoS rule), the SSC mode, the S-NSSAI, and the IPv4
address (allocated IPv4 address). For example, a format of the SM
response message is (cause, N2 SM information (PDU session ID, QoS
profile(s), CN tunnel info), N1 SM information (PDU session
establishment accept (authorized QoS rule, SSC mode, S-NSSAI,
allocated IPv4 address))). The CN tunnel information in the N2 SM
information is specifically a core network address of an N3 tunnel.
The authorized QoS rule includes a QoS rule identifier, an
identifier of an associated QoS flow, a packet filter set, a
priority value, and terminal-related QoS parameters. The QoS rule
identifier is unique in a PDU session. For example, the
terminal-related QoS parameters include a 5G QoS indicator (5G QoS
Indicator, 5QI), a guaranteed bit rate (guaranteed bit rate, GBR),
a maximum bit rate (maximum bit rate, MBR), and the like.
[0250] S111. The AMF entity sends an N2 PDU session request message
to a RAN entity.
[0251] Specifically, the AMF entity sends the N2 PDU session
request (N2 PDU session request) message to the RAN entity, and the
N2 PDU session request includes the N2 SM information and a NAS
message (NAS message). The NAS message includes the PDU session
identifier and the PDU session establishment accept message. For
example, a format of the N2 PDU session request is (N2 SM
information, NAS message (PDU session ID, PDU session establishment
accept)).
[0252] S112a. The RAN entity sends a radio resource control (radio
resource control, RRC) connection reconfiguration message to the
terminal.
[0253] Specifically, the RAN entity sends the RRC connection
reconfiguration (RRC connection reconfiguration) message to the
terminal, and the RAN entity allocates a necessary RAN resource
based on a QoS rule. For example, the RAN entity allocates N3
tunnel information. In addition, the RAN forwards a NAS message
(PDU session ID, N1 SM information (PDU session establishment
accept)) to the terminal.
[0254] S112b. The terminal may send an RRC connection
reconfiguration response message to the RAN entity.
[0255] S113. The RAN entity sends an N2 PDU session establishment
response message to the AMF entity.
[0256] Specifically, the N2 PDU session response (N2 PDU session
response) message includes the PDU session identifier, a cause
value, and N2 SM information. The N2 SM information herein includes
the PDU session identifier, access network tunnel information
((R)AN tunnel info), and a list of accepted/rejected QoS profile(s)
(list of accepted/rejected QoS profile(s)). For example, a format
of the N2 PDU session establishment response message is (PDU
session ID, cause, N2 SM information (PDU session ID, (R)AN tunnel
info, list of accepted/rejected QoS profile(s))).
[0257] S114. The AMF entity sends an SM request message to the SMF
entity.
[0258] Specifically, the SM request (SM Request) message includes
the N2 SM information in step S113. Then, the AMF entity forwards,
to the SMF entity, the N2 SM information from the RAN entity.
[0259] S115a. The SMF entity sends an N4 session
establishment/modification request message to the UPF entity.
[0260] Specifically, if an N4 session (N4 session) is not
established, the SMF entity initiates an N4 session establishment
procedure. If an N4 session has been established, the SMF entity
initiates an N4 session modification procedure, to update access
network (access network, AN) tunnel information and core network
(core network, CN) tunnel information.
[0261] S115b. The UPF entity sends an N4 session
establishment/modification response message to the SMF entity.
[0262] S116. The SMF entity sends an SM response message to the AMF
entity.
[0263] Specifically, the SM response (SM response) message includes
a cause value cause.
[0264] S117. The SMF entity sends an IPv6 router advertisement
message to the UPF entity.
[0265] Specifically, the IPv6 router advertisement message (IPv6
router advertisement) carries an IPv6 address prefix allocated by
the SMF entity.
[0266] S118. The SMF entity releases a user plane resource.
[0267] Specifically, if the PDU session is triggered by switching
between 3GPP and non-3GPP, the SMF entity needs to release an
original user plane resource on an access side.
[0268] S119. The SMF entity triggers a unified data management
register service network function (UDM-Unified data management,
UDM_Register UE serving NF) service.
[0269] Specifically, if the identifier of the SMF entity is not
included in step 14b, the SMF entity triggers the UDM_Register UE
serving NF service, so that the SMF entity exchanges a service
request with the PCF entity and the UDM entity. The service request
includes an address of the SMF entity and a DNN, the UDM entity
needs to store the identifier of the SMF entity, the address of the
SMF entity, and an associated DNN.
[0270] It can be learned in FIG. 3A to FIG. 3C, the terminal
actively initiates a PDU session establishment procedure.
[0271] When the terminal receives downlink data through a broadcast
path, the terminal needs to be switched from the broadcast path to
a unicast path. In a first case, when the terminal enters a
broadcast receive mode, for example, when the terminal enters the
broadcast receive mode starting from pre-configuration startup, the
terminal may start to receive broadcast data. When broadcast
received quality is poor, a network entity on a network side needs
to switch a receive transmission mode of the terminal to a unicast
transmission mode. In other words, the terminal is switched from
the broadcast path to the unicast path. In this case, a unicast
session establishment procedure needs to be triggered to establish
the unicast path. In a second case, when the terminal already
performs a unicast session, but the unicast session cannot meet a
requirement of a current service, a procedure of establishing a new
unicast session needs to be triggered to establish a new unicast
path. In a third case, when broadcast received quality reported by
most terminals received on a network side is poor, a network entity
on the network side may switch downlink data of a service
transmitted on the broadcast path to a unicast transmission mode,
and further, the network entity on the network side needs to switch
all terminals connected to the network side to the unicast
transmission mode. Therefore, the network entity on the network
side needs to switch, to the unicast transmission mode, another
terminal that does not report poor broadcast received quality, and
a unicast session establishment procedure needs to be triggered. In
a fourth case, a network side needs to switch a terminal in a
specific group from a broadcast transmission mode to a unicast
transmission mode, so that a unicast session establishment
procedure needs to be triggered. In the foregoing several cases, in
the prior art, a terminal can only actively initiate a PDU session
establishment procedure, or a terminal can only actively initiate a
PDU session establishment procedure after an application server
sends a notification to the terminal. In both manners, the terminal
actively initiates the PDU session establishment procedure, and a
process shown in FIG. 3A to FIG. 3C may be used.
[0272] In the prior art, FIG. 4 is a signaling diagram of a method
for triggering PDU session establishment according to the prior
art. As shown in FIG. 4, the method for triggering PDU session
establishment in the prior art is specifically described as
follows:
[0273] S31. An application server (Application server) sends a
device trigger request message to an NEF entity.
[0274] Specifically, the NEF receives the device trigger request
(device trigger request) message sent by the application server.
The device trigger request message includes an external identifier
(external identifier) or a mobile station international ISDN number
(MSISDN). The device trigger request message further includes a
requester identifier (requester identifier), a validity period
(validity period), an application port ID (application port ID),
and a trigger payload (trigger payload). The application port ID is
used to trigger an addressing function on a terminal, and the
trigger payload includes information about a target application
server on the terminal or includes information that is used by the
terminal to find the target application server.
[0275] In addition, after S31, the NEF entity may complete
authentication and authorization.
[0276] S32. The NEF entity invokes a subscriber serving network
function.
[0277] Specifically, the NEF entity may obtain a subscription
permanent identifier (subscription permanent identifier, SUPI) of
the terminal by using a get subscriber serving NF (external
identifier or MSISDN, NF type) message. The NF type represents a
network function type, for example, indicates an AMF entity or an
SMF entity.
[0278] S33. The NEF entity sends a device trigger request message
to the AMF entity.
[0279] Specifically, the device trigger request message includes a
UE permanent ID (UE permanent ID) and a non-access stratum
signaling container (NAS Container, NAS). The NAS container
includes the application port ID and the trigger payload. For
example, the device triggering request message is a device trigger
request (UE permanent ID, NAS container).
[0280] S34a. The AMF entity sends a device trigger request message
to the terminal.
[0281] Specifically, the AMF entity sends the device trigger
request message to the terminal, and in this case, the device
trigger request message may include only a NAS container. In this
case, if the terminal is not in connected mode, the AMF entity
pages the terminal.
[0282] S34b. The terminal sends a device trigger response message
to the AMF entity.
[0283] S35. The AMF entity sends a device trigger response message
to the NEF entity.
[0284] Specifically, after the terminal receives the NAS container,
because the trigger payload identifies an application server that
needs to be notified and information of which the application
server needs to be notified. For example, the trigger payload
indicates to request to establish a PDU session, and the terminal
may further determine the application server that needs to be
notified and the information of which the application server needs
to be notified. Then, the AMF entity sends the device trigger
response (device trigger response) message to the NEF entity.
[0285] S36. The NEF entity sends the device trigger response
message to the application server.
[0286] After step S36, the steps shown in FIG. 3A to FIG. 3C are
performed.
[0287] This application first provides a method and a device for
actively initiating a PDU session establishment procedure on a
network side.
[0288] FIG. 5 is a flowchart of a session establishment method
according to an embodiment of this application. As shown in FIG. 5,
this embodiment of this application provides a session
establishment method. The method is performed by an SMF entity. The
method is specifically described as follows:
[0289] 101. The SMF entity sends a PDU session establishment
request message to a terminal, where the PDU session establishment
request message is used to request to establish a PDU session.
[0290] In an optional implementation, the PDU session establishment
request message includes session establishment assistance
information of the PDU session. Alternatively, the method provided
in this embodiment further includes: sending, by the SMF entity,
session establishment assistance information of the PDU session to
the terminal.
[0291] The session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0292] In an optional implementation, the method provided in this
embodiment further includes: selecting, by the SMF entity based on
the broadcast session identifier, a UPF entity corresponding to the
broadcast session, and sending a user plane session request to the
UPF entity corresponding to the broadcast session; or selecting, by
the SMF entity based on the group identifier, a UPF entity
corresponding to the group identifier, and sending a user plane
session request to the UPF entity corresponding to the group
identifier. The user plane session request includes user plane
forwarding rule information of the PDU session.
[0293] In an optional implementation, the PDU session establishment
request message includes a session identifier of the PDU session.
The method provided in this embodiment further includes:
allocating, by the SMF entity, a session identifier to the PDU
session.
[0294] In an optional implementation, the PDU session establishment
request message includes information about a quality of service
flow (quality of service flow, QoS flow) corresponding to the PDU
session. The QoS flow is a finest granularity for data forwarding
and processing in 5G. All data mapped to a same QoS flow uses a
same forwarding and processing policy. The forwarding and
processing policy includes, for example, a schedule policy, a queue
management policy, a data shaping policy, and a radio link control
protocol (radio link control, RLC) configuration policy. Different
QoS flows such as, a QoS profile (QoS profile), a QoS rule (QoS
rule), and a service data flow template (service data flow
template, SDF template) use different QoS forwarding rules, and
different QoS flows may be identified by using QoS flow
identifiers. The QoS profile includes but is not limited to the
following QoS parameters: a 5QI, an allocation and retention
priority (allocation and retention priority, ARP), a reflective QoS
attribute (reflective QoS attribute, RQA), a guaranteed flow bit
rate-uplink and downlink (guaranteed flow bit rate-up link and down
link, GFBR-UL and DL), a maximum flow bit rate (maximum flow bit
rate, MFBR), and the like. The QoS rule is used to classify
(classification) and mark (marking) user plane data, and includes a
QoS rule identifier, a QFI (an identifier of an associated QoS
flow), a packet filter (packet filter) set, and a priority value.
The QoS rule identifier is unique in a PDU session. A dynamically
allocated QoS rule also includes UE-related QoS parameters, such as
a 5QI, a GBR, and an MBR. The SDF template is used to classify
downlink data, and is used to determine a QoS flow on which a
downlink data packet is transmitted.
[0295] In an optional implementation, the PDU session request
message includes an identifier of the terminal. Alternatively, the
method provided in this embodiment further includes: sending, by
the SMF entity, an identifier of the terminal to an AMF entity.
[0296] The identifier of the terminal may be an SUPI, a
subscription concealed identifier (subscription concealed
identifier, SUCI), a permanent equipment identifier (permanent
equipment identifier, PEI), or a protocol address of a user. The
protocol address of the user is, for example, an IPv4 address, an
IPv6 address, or a media access control (media access control, MAC)
address. Description of the identifier of the terminal in another
embodiment of this application is the same as the foregoing
description.
[0297] For example, when the SMF entity determines that a PDU
session needs to be established for the terminal, or when the SMF
entity determines that the terminal needs to be switched from a
broadcast path to a unicast path, the SMF entity sends a PDU
session establishment request message to the AMF entity. The PDU
session establishment request message is used to request to
establish a PDU session. Then, the AMF entity sends the PDU session
establishment request message to a RAN entity. Then, the RAN entity
sends the PDU session establishment request message to the
terminal. Optionally, the PDU session establishment request message
includes the information about the QoS flow corresponding to the
PDU session. Description of the information about the QoS flow is
the same as that in the foregoing, and details are not described
herein again.
[0298] Specifically, step 101 includes the following steps.
[0299] S21. When the SMF entity determines that the PDU session
needs to be established for the terminal, or when the SMF entity
determines that downlink data for the terminal needs to be switched
from the broadcast path to the unicast path, the SMF entity
determines to establish the PDU session for the terminal.
Optionally, in this case, the SMF entity may allocate a session
identifier to the PDU session.
[0300] S22a. Optionally, the SMF entity sends a subscription data
request message to a UDM entity. Specifically, if the SMF entity
has not obtained SM-related subscription information of the
terminal from a DNN entity, the SMF entity needs to send the
subscription data request message to the UDM entity to obtain the
SM-related subscription information. The subscription data request
message includes a subscription identifier and a DNN. For example,
a format of the subscription data request message is (subscriber
permanent ID, DNN), and the subscriber permanent ID is the
subscription identifier.
[0301] S22b. Optionally, the UDM entity sends the subscription
information to the SMF entity. Specifically, the UDM entity sends a
subscription data response message to the SMF entity. The
subscription data response message includes the subscription
information, and the subscription information includes, for
example, an authorized PDU type, an authorized SSC mode, and a
default QoS profile. Then, the SMF entity performs an authorization
check on the subscription information. If the SMF entity determines
that the authorization check fails, the SMF entity sends NAS
signaling to the terminal. The NAS signaling indicates that a
session establishment request of the terminal is rejected.
[0302] S23. Optionally, the SMF entity completes
authorization/authentication for PDU session establishment. A
process in which the SMF entity completes the
authorization/authentication for the PDU session establishment may
be performed before or after any step in this embodiment.
[0303] S24. The SMF entity selects the UPF entity, and the SMF
entity selects an SSC mode. Specifically, the SMF entity selects
the UPF entity in the following several manners. Manner 1: When the
SMF entity determines that a unicast session needs to be
established for the terminal, the terminal selects a UPF entity
according to a prior-art rule. Manner 2: When the SMF entity
switches the terminal from the broadcast path to the unicast path,
the SMF entity has learned of the broadcast session identifier, the
SMF entity may select, based on the broadcast session identifier,
the UPF entity corresponding to the broadcast session. It can be
learned that the broadcast session identifier is used to represent
the broadcast session in which the terminal participates. Manner 3:
When the SMF entity determines to establish a unicast session for
the terminal in the group or determines to switch the terminal in
the group from the broadcast path to the unicast path, the SMF
entity has learned of the group identifier, and the SMF entity may
select, based on the group identifier, the UPF entity corresponding
to the group identifier. It can be learned that the group
identifier is used to represent the group including the terminal.
Because the SMF entity selects, for the PDU session, the UPF entity
corresponding to the broadcast session, the SMF entity may use a
media forwarding policy the same as that used for the broadcast
session. Alternatively, because the SMF entity selects the UPF
entity corresponding to the group, the SMF entity may use a
forwarding policy the same as that of the group or a media
forwarding policy the same as that of another terminal in the
group. In addition, the SMF entity may determine, based on the
broadcast session identifier or the group identifier, an AMF entity
to which the terminal is connected. In other words, the SMF entity
may determine an AMF entity through which the terminal accesses a
network. The group identifier may be a PLMN internal group
identifier, or may be a PLMN external group identifier, for
example, a group identifier established and maintained by a
third-party application. PLMN internal group identifiers may
alternatively one-to-one correspond to PLMN external groups.
[0304] S25. Optionally, the SMF entity initiates a PDU-CAN session
establishment procedure. Specifically, if a dynamic PCC is
deployed, and a PDU-CAN session is not established, the SMF entity
initiates the PDU-CAN session establishment procedure to a PCF
entity, and then the SMF entity obtains a default PCC rule from the
PCF entity. If the SMF entity modifies an established PDU session,
the SMF entity initiates PDU-CAN session modification, and the SMF
entity sends an allocated IP address of the terminal to the PCF
entity.
[0305] S26a. The SMF entity sends the user plane session request to
the selected UPF entity. The SMF entity sends the user plane
session request to the selected UPF entity in the following several
manners. Manner 1: After the SMF entity selects the UPF entity
corresponding to the broadcast session, the SMF entity sends the
user plane session request to the UPF entity corresponding to the
broadcast session. Manner 2: After the SMF entity selects the UPF
entity corresponding to the group identifier, the SMF entity sends
the user plane session request to the UPF entity corresponding to
the group identifier. The user plane session request sent by the
SMF entity includes the user plane forwarding rule information of
the PDU session. The user plane session request is used to
establish a user plane connection of the PDU session. The user
plane session request may be referred to as an N4 session.
Therefore, this step may alternatively be referred to as: The SMF
entity initiates an N4 session establishment/modification procedure
to the selected UPF entity. The user plane forwarding rule
information of the PDU session may include one or more of the
following information: packet detection (packet detection)
information, enforcement and reporting rule (enforcement and
reporting rules) information, CN tunnel information, and the like.
The packet detection information and the execution and reporting
rule information need to be applied to the PUD session. In this
step, the SMF entity interacts with the UPF entity, to establish a
user plane connection of a session and create a unicast path.
[0306] In an example, the UPF entity may set a user plane data
transmission path of a multicast service based on the user plane
forwarding rule information, for example, set a correspondence
between a session identifier, a user plane multicast address of the
multicast service, and an access network node. If the UPF entity
further receives a downlink receiver address of the access network
node and/or a tunnel identifier from a multicast session management
network element, the UPF entity may further set a correspondence
between the broadcast path and the downlink receiver address of the
access network node. Alternatively, the UPF entity may set a
correspondence between the broadcast path and the tunnel
identifier, or set a correspondence between the broadcast path, the
downlink receive address of the access network node, and the tunnel
identifier. The broadcast path may use a broadcast path identifier,
and may correspond to a temporary group identity (temporary group
identity, TMGI) in an LTE system, or correspond to a combination of
a TMGI and an MBMS flow ID (MBMS flow ID).
[0307] In another example, the UPF entity may map a received data
packet to a broadcast data flow based on the user plane forwarding
rule information, and then the UPF entity sends the data packet
according to a QoS forwarding policy of the broadcast data
flow.
[0308] S26b. The UPF entity sends an N4 session
establishment/modification response message to the SMF entity,
where the N4 session establishment/modification response message
may include the CN tunnel information.
[0309] S27. The SMF entity sends the PDU session establishment
request message to the AMF entity. Optionally, the PDU session
establishment request message carries the session identifier
allocated by the SMF entity to the PDU session. Specifically, the
SMF entity sends the PDU session establishment request message to
the AMF entity in the following several manners. Manner 1: The SMF
entity sends the PDU session establishment request message to the
AMF entity. Manner 2: The SMF entity allocates the session
identifier to the PDU session, and then the SMF entity sends the
PDU session establishment request message to the AMF entity. The
PDU session establishment request message carries the session
identifier allocated by the SMF entity to the PDU session. Manner
3: The SMF entity allocates the session identifier to the PDU
session, and then the SMF entity sends an SMF request message to
the AMF entity. The SMF request message includes the PDU session
establishment request message and the session identifier allocated
by the SMF entity to the PDU session.
[0310] Optionally, the SMF entity may send the session
establishment assistance information of the PDU session to the AMF
entity. The SMF entity sends the session establishment assistance
information of the PDU session to the AMF entity in the following
several manners. Manner 1: The SMF entity sends the PDU session
establishment request message including the session establishment
assistance information of the PDU session to the AMF entity. Manner
2: The SMF entity sends an SMF request message including the
session establishment assistance information of the PDU session and
the PDU session establishment request message to the AMF entity.
The session establishment assistance information of the PDU session
includes the broadcast session identifier and/or the group
identifier.
[0311] For example, the SMF entity sends an SM request message to
the AMF entity. The message is an N11 message, the SM request
message is represented by using an SM request, and a format of the
SM request is an SM request (PDU session establishment request, UE
ID), session establishment assistance information ([broadcast
session ID (or group identifier)]), [PDU session ID]). The PDU
session establishment request is the PDU session establishment
request message, the PDU session establishment request is NAS
signaling, and the PDU session establishment request is used to
request the terminal to establish a PDU session. The UE ID is a
subscription identifier of the terminal. The broadcast session ID
is an identifier of the broadcast session established for the
terminal, and the group identifier is the identifier of the group
including the terminal. The PDU session ID is the session
identifier allocated by the SMF entity to the to-be-established PDU
session. The session establishment assistance information may
assist the AMF entity in determining a RAN entity through which the
terminal accesses a network, and the session establishment
assistance information is used by the AMF entity to send a paging
message.
[0312] Optionally, after the AMF entity receives the session
establishment assistance information, of the PDU session, that is
sent by the SMF entity, because the session establishment
assistance information of the PDU session includes one or more of
the broadcast session identifier and the group identifier, the AMF
entity select a RAN entity based on the session establishment
assistance information of the PDU session. For example, the AMF
entity selects a RAN entity corresponding to the broadcast session
identifier, or the AMF entity selects a RAN entity corresponding to
the group identifier.
[0313] Optionally, because the PDU session request message includes
the identifier of the terminal, or the SMF entity sends the
identifier of the terminal to the AMF entity, the AMF entity may
select, based on the identifier of the terminal, a RAN entity
corresponding to the identifier of the terminal, namely, a RAN
entity through which the terminal accesses the network.
[0314] S28. The AMF entity sends the PDU session establishment
request message to the selected RAN entity. Optionally, the PDU
session establishment request message carries the session
identifier allocated by the SMF entity to the PDU session, or the
AMF entity sends, to the RAN entity, the session identifier
allocated by the SMF entity to the PDU session. Optionally, the PDU
session establishment request message carries the session
establishment assistance information of the PDU session, or the AMF
entity sends the session establishment assistance information of
the PDU session to the RAN entity. For example, the AMF entity
sends an N2 PDU session request message to the RAN entity. The N2
PDU session request message includes N2 SM information and a NAS
message. The N2 SM information includes the session identifier and
the session establishment assistance information of the PDU
session, and the NAS message includes the session identifier and
the session establishment assistance information of the PDU
session, and the PDU session establishment request message. The N2
PDU session request message may be represented by using an N2 PDU
session request: N2 PDU session request (N2 SM information ([PDU
session ID], session establishment assistance information
([broadcast session ID (or group identifier)])), NAS message ([PDU
session ID], session establishment assistance information
([broadcast session ID (or group identifier)]), PDU session
establishment request)). The N2 SM information is the N2 SM
information, and the NAS message is the NAS message.
[0315] S29. The RAN entity sends the PDU session establishment
request message to the terminal. Optionally, the PDU session
establishment request message carries the session identifier
allocated by the SMF entity to the PDU session, or the AMF entity
sends, to the RAN entity, the session identifier allocated by the
SMF entity to the PDU session. Optionally, the PDU session
establishment request message carries the session establishment
assistance information of the PDU session, or the AMF entity sends
the session establishment assistance information of the PDU session
to the RAN entity.
[0316] For example, after the RAN entity receives the N2 PDU
session request message sent by the AMF entity, the RAN entity adds
the NAS message in the N2 PDU session request message into an RRC
message, and sends the RRC message to the terminal. For another
example, the RAN entity sends a PDU session establishment request
(session establishment assistance information ([broadcast session
ID]), [PDU session ID]) to the terminal.
[0317] 102. The SMF entity receives a PDU session establishment
response message from the terminal.
[0318] In an optional implementation, the PDU session establishment
response message includes a session identifier of the PDU session.
Alternatively, the method provided in this embodiment further
includes: receiving, by the SMF entity, a session identifier of the
PDU session from the terminal.
[0319] For example, after the terminal receives the PDU session
establishment request message, the terminal generates the PDU
session establishment response message, and the terminal sends the
PDU session establishment response message to the RAN entity. Then,
the RAN entity sends the PDU session establishment response message
to the AMF entity. Then, the AMF entity sends the PDU session
establishment response message to the SMF entity.
[0320] Specifically, step 102 includes the following steps.
[0321] S210a. After step S29, the terminal sends the PDU session
establishment response message to the RAN entity. Optionally, the
terminal also sends the session identifier of the PDU session to
the RAN entity. Specifically, the terminal sends the session
identifier of the PDU session to the RAN entity in the following
several manners. Manner 1: The terminal sends the PDU session
establishment response message to the RAN entity, and the PDU
session establishment response message carries the session
identifier of the PDU session. Manner 2: The terminal sends the PDU
session establishment response message and the session identifier
of the PDU session to the RAN entity.
[0322] In addition, the terminal sends the session identifier of
the PDU session to the RAN entity in the following several cases:
In a first case, the terminal does not receive a session
identifier, of the PDU session, that is sent by the SMF entity, and
the terminal allocates a session identifier of the PDU session.
Then the terminal sends, to the RAN entity, the PDU session
establishment response message including the session identifier, of
the PDU session, that is allocated by the terminal; or the terminal
directly sends, to the RAN entity, the session identifier, of the
PDU session, that is allocated by the terminal. In a second case,
the terminal receives the session identifier, of the PDU session,
that is sent by the SMF entity, the session identifier, of the PDU
session, that is sent by the SMF entity is a session identifier
allocated by the SMF entity, and the terminal refuses to use the
session identifier, of the PDU session, that is allocated by the
SMF entity. Then, the terminal reallocates a session identifier of
the PDU session, and the terminal sends, to the RAN entity, the PDU
session establishment response message including the session
identifier, of the PDU session, that is allocated by the terminal,
or the terminal directly sends, to the RAN entity, the session
identifier, of the PDU session, that is allocated by the terminal.
In a third case, the terminal receives the session identifier, of
the PDU session, that is sent by the SMF entity, the session
identifier, of the PDU session, that is sent by the SMF entity is a
session identifier allocated by the SMF entity, and the terminal
determines to use the session identifier, of the PDU session, that
is allocated by the SMF entity. Then, the terminal sends, to the
RAN entity, the PDU session establishment response message
including the received session identifier of the PDU session, or
the terminal directly sends the received session identifier of the
PDU session to the RAN entity.
[0323] S210b. The RAN entity sends the PDU session establishment
response message to the AMF entity, where the PDU session
establishment response message may be an N2 PDU session
establishment response message. Optionally, the PDU session
establishment response message includes the session identifier of
the PDU session, or the RAN entity sends the session identifier of
the PDU session to the AMF entity.
[0324] Then, if the AMF entity determines that the received session
identifier of the PDU session is the session identifier allocated
by the terminal, the AMF entity replaces a previously stored
session identifier allocated by the SMF entity with the received
session identifier of the PDU session, or the AMF entity directly
stores the session identifier of the PDU session.
[0325] S211. The AMF entity sends the PDU session establishment
response message to the SMF entity. Optionally, the PDU session
establishment response message includes the session identifier of
the PDU session, or the AMF entity sends the session identifier of
the PDU session to the SMF entity. For example, the AMF entity
sends an SM request with N2 information message to the SMF entity.
The SM request with N2 information message includes the PDU session
establishment response message and the session identifier of the
PDU session. Then, if the SMF entity determines that the received
session identifier of the PDU session is the session identifier
allocated by the terminal, the SMF entity replaces a previously
stored session identifier allocated by the current SMF entity with
the received session identifier of the PDU session, or the SMF
entity directly stores the session identifier of the PDU session.
For example, the SMF entity replaces a previously stored session
identifier PDU session ID allocated by the current SMF entity with
the received session identifier PDU session ID' of the PDU
session.
[0326] S212a. The SMF entity initiates an N4 session establishment
procedure. Specifically, if an N4 session (N4 session) is not
established, the SMF entity initiates the N4 session establishment
procedure. If an N4 session has been established, the SMF entity
initiates an N4 session modification procedure, to update AN tunnel
information and CN tunnel information.
[0327] S212b. The SMF entity sends an SM response message to the
AMF entity. Optionally, the SM response message includes a cause
value cause.
[0328] S213. Optionally, the SMF entity sends an IPv6 router
advertisement message to the UPF entity. Optionally, the IPv6
router advertisement message carries an IPv6 address prefix
allocated by the SMF entity.
[0329] After the SMF entity sends the IPv6 router advertisement
message to the UPF entity, the UPF entity may send the IPv6 router
advertisement message to the terminal.
[0330] By now, the PDU session establishment procedure is
completed, and then the UPF entity can send downlink data to the
terminal through the unicast path by using the newly established
PDU session.
[0331] According to the method provided in the foregoing
embodiment, the SMF entity sends the PDU session establishment
request message to the terminal, where the PDU session
establishment request message is used to request to establish the
PDU session. The SMF entity receives the PDU session establishment
response message from the terminal. Optionally, the PDU session
establishment response message includes the session identifier of
the PDU session, or the SMF entity receives the session identifier
of the PDU session from the terminal. Optionally, the SMF entity
allocates the session identifier to the PDU session, and the PDU
session establishment request message includes the session
identifier of the PDU session. Therefore, a method for actively
initiating the PDU session establishment procedure on a network
side is provided. When the terminal needs to be switched from a
broadcast path to the unicast path, the PDU session may be
established for the terminal on the network side, to establish the
unicast path. In addition, because it can be ensured that a same
UPF entity is selected for the broadcast session on the broadcast
path and for the unicast session on the unicast path on the network
side, it can be ensured that user plane data is consistent and
synchronized on the broadcast path and the unicast path when the
user plane data is switched from the broadcast path to the unicast
path. Negotiation performed when user plane downlink data is
switched from the broadcast path to the unicast path is avoided, so
that a delay of switching from the broadcast path to the unicast
path can be reduced, to ensure fast and continuous switching of
data, and ensure fast switching that meets service continuity
requirements of a broadcast mode and a unicast mode. In addition,
the network side triggers the terminal to establish the PDU
session, and this can reduce signaling interaction in a process in
which the terminal establishes the PDU session with the network
side, and further reduce a delay.
[0332] FIG. 6 is a flowchart of another session establishment
method according to an embodiment of this application. As shown in
FIG. 6, this embodiment of this application provides another
session establishment method. The method is performed by a
terminal. The method is specifically described as follows:
[0333] 201. The terminal receives a PDU session establishment
request message from an SMF entity, where the PDU session
establishment request message is used to request to establish a PDU
session.
[0334] In an optional implementation, the PDU session establishment
request message includes session establishment assistance
information of the PDU session, and the method provided in this
embodiment further includes: obtaining, by the terminal based on
the session establishment assistance information of the PDU
session, information about a QoS flow corresponding to the PDU
session. Alternatively, the method provided in this embodiment
further includes: receiving, by terminal, session establishment
assistance information of the PDU session from the SMF entity, and
obtaining, based on the session establishment assistance
information of the PDU session, information about a QoS flow
corresponding to the PDU session. Description of the QoS flow is
the same as that in the foregoing embodiment, and details are not
described herein again.
[0335] The session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0336] In an optional implementation, the PDU session establishment
request message includes a session identifier of the PDU
session.
[0337] 202. The terminal sends a PDU session establishment response
message to the SMF entity based on the PDU session establishment
request message.
[0338] In an optional implementation, the PDU session establishment
response message includes a session identifier of the PDU session.
Alternatively, the method provided in this embodiment further
includes: sending, by the terminal, a session identifier of the PDU
session to the SMF entity.
[0339] In an optional implementation, the method provided in this
embodiment may further include step 203:
[0340] 203. The terminal allocates a session identifier to the PDU
session based on the PDU session establishment request message.
[0341] For steps in this embodiment, refer to descriptions of the
steps in FIG. 5. Details are not described again.
[0342] According to the method provided in the foregoing
embodiment, the terminal receives the PDU session establishment
request message from the SMF entity, where the PDU session
establishment request message is used to request to establish the
PDU session. The terminal sends the PDU session establishment
response message to the SMF entity. Optionally, the PDU session
establishment response message includes the session identifier of
the PDU session, or the SMF entity receives the session identifier
of the PDU session from the terminal. Optionally, the SMF entity
allocates the session identifier to the PDU session, and the PDU
session establishment request message includes the session
identifier of the PDU session. Therefore, a method for actively
initiating the PDU session establishment procedure on a network
side is provided. When the terminal needs to be switched from a
broadcast path to a unicast path, the PDU session may be
established for the terminal on the network side, to establish the
unicast path. In addition, because it can be ensured that a same
UPF entity is selected by a broadcast session for the broadcast
path and is selected by a unicast session for the unicast path on
the network side, it can be ensured that user plane data is
consistent and synchronized on the broadcast path and the unicast
path when the user plane data is switched from the broadcast path
to the unicast path. Negotiation performed when user plane downlink
data is switched from the broadcast path to the unicast path is
avoided, so that a delay of switching from the broadcast path to
the unicast path can be reduced, to ensure fast and continuous
switching of data, and ensure fast switching that meets service
continuity requirements of a broadcast mode and a unicast mode. In
addition, the network side triggers the terminal to establish the
PDU session, and this can reduce signaling interaction in a process
in which the terminal establishes the PDU session with the network
side, and further reduce a delay.
[0343] FIG. 7 is a flowchart of still another session establishment
method according to an embodiment of this application. As shown in
FIG. 7, this embodiment of this application provides still another
session establishment method. The method is performed by an AMF
entity. The method is specifically described as follows:
[0344] 301. The AMF entity receives a PDU session request message
from an SMF entity, where the PDU session establishment request
message is used to request to establish a PDU session.
[0345] In an optional implementation, the PDU session establishment
request message includes session establishment assistance
information of the PDU session. Alternatively, the method provided
in this embodiment further includes: receiving, by the AMF entity,
session establishment assistance information of the PDU session
from the SMF entity.
[0346] The session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which a terminal participates, and
the group identifier is used to represent a group including the
terminal.
[0347] In an optional implementation, the PDU session request
message includes an identifier of the terminal. Alternatively, the
method provided in this embodiment further includes: receiving, by
the AMF entity, an identifier of the terminal from the SMF
entity.
[0348] 302. The AMF entity sends the PDU session request message to
the terminal.
[0349] In an optional implementation, step 302 includes the
following two implementations:
[0350] In a first implementation of step 302, the AMF entity
selects a radio access network function RAN entity based on the
session establishment assistance information of the PDU session,
and the AMF entity sends the PDU session request message to the
terminal through the RAN entity.
[0351] In a second implementation of step 302, the AMF entity
selects a RAN entity based on the identifier of the terminal, and
the AMF entity sends the PDU session request message to the
terminal through the RAN entity.
[0352] In an example, optionally, after the AMF entity receives the
session establishment assistance information, of the PDU session,
that is sent by the SMF entity, because the session establishment
assistance information of the PDU session includes one or more of
the broadcast session identifier and the group identifier, the AMF
entity select a RAN entity based on the session establishment
assistance information of the PDU session. For example, the AMF
entity selects a RAN entity corresponding to the broadcast session
identifier, or the AMF entity selects a RAN entity corresponding to
the group identifier.
[0353] Optionally, because the PDU session request message includes
the identifier of the terminal, or the SMF entity sends the
identifier of the terminal to the AMF entity, the AMF entity may
select, based on the identifier of the terminal, a RAN entity
corresponding to the identifier of the terminal, namely, a RAN
entity through which the terminal accesses a network.
[0354] 303. The AMF entity receives a PDU session establishment
response message from the terminal.
[0355] 304. The AMF entity sends the PDU session establishment
response message to the SMF entity.
[0356] For steps in this embodiment, refer to descriptions of the
steps in FIG. 5. Details are not described again.
[0357] According to the method provided in the foregoing
embodiment, the AMF entity receives the PDU session request message
from the SMF entity, where the PDU session establishment request
message is used to request to establish the PDU session. The AMF
entity sends the PDU session request message to the terminal. The
AMF entity receives the PDU session establishment response message
from the terminal, and sends the PDU session establishment response
message to the SMF entity. Optionally, the PDU session
establishment response message includes a session identifier of the
PDU session, or the SMF entity receives a session identifier of the
PDU session from the terminal. Optionally, the SMF entity allocates
a session identifier to the PDU session, and the PDU session
establishment request message includes the session identifier of
the PDU session. Therefore, a method for actively initiating the
PDU session establishment procedure on a network side is provided.
When the terminal needs to be switched from a broadcast path to a
unicast path, the PDU session may be established for the terminal
on the network side, to establish the unicast path. In addition,
because it can be ensured that a same UPF entity is selected by the
broadcast session for the broadcast path and is selected by a
unicast session for the unicast path on the network side, it can be
ensured that user plane data is consistent and synchronized on the
broadcast path and the unicast path when the user plane data is
switched from the broadcast path to the unicast path. Negotiation
performed when user plane downlink data is switched from the
broadcast path to the unicast path is avoided, so that a delay of
switching from the broadcast path to the unicast path can be
reduced, to ensure fast and continuous switching of data, and
ensure fast switching that meets service continuity requirements of
a broadcast mode and a unicast mode. In addition, the network side
triggers the terminal to establish the PDU session, and this can
reduce signaling interaction in a process in which the terminal
establishes the PDU session with the network side, and further
reduce a delay.
[0358] FIG. 8A and FIG. 8B are a signaling diagram of yet another
session establishment method according to an embodiment of this
application. As shown in FIG. 8A and FIG. 8B, this embodiment of
this application provides yet another session establishment method.
The method is specifically described as follows:
[0359] S71. An SMF entity determines to establish a PDU session for
a terminal, and the SMF entity allocates a session identifier PDU
session ID to the PDU session.
[0360] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0361] S72a. Optionally, the SMF entity sends a subscription data
request message to a UDM entity.
[0362] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0363] S72b. Optionally, the UDM entity sends subscription
information to the SMF entity.
[0364] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0365] S73. The SMF entity completes authorization/authentication
for PDU session establishment.
[0366] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0367] S74. The SMF entity selects a UPF entity.
[0368] In an optional implementation, the SMF entity selects, based
on a broadcast session identifier, a user plane function UPF entity
corresponding to a broadcast session, or the SMF entity selects,
based on a group identifier, a UPF entity corresponding to the
group identifier.
[0369] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0370] S75. Optionally, the SMF entity initiates a PDU-CAN session
establishment procedure.
[0371] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0372] S76a. Optionally, the SMF entity sends a user plane session
request to the selected UPF entity, where the user plane session
request includes user plane forwarding rule information of the PDU
session.
[0373] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0374] S76b. Optionally, the UPF entity sends CN tunnel information
to the SMF entity.
[0375] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0376] S77. The SMF entity sends a PDU session establishment
request message to an AMF entity.
[0377] In this step, the PDU session establishment request message
includes the session identifier PDU session ID of the PDU session,
or the SMF entity sends the PDU session establishment request
message and the session identifier PDU session ID of the PDU
session to the AMF entity.
[0378] In an optional implementation, the PDU session establishment
request message includes session establishment assistance
information of the PDU session. Alternatively, the method provided
in this embodiment further includes: sending, by the SMF entity,
session establishment assistance information of the PDU session to
the terminal.
[0379] The session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0380] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0381] S78. The AMF entity sends the PDU session establishment
request message to a RAN entity.
[0382] In this step, the PDU session establishment request message
includes the session identifier PDU session ID of the PDU session,
or the AMF entity sends the PDU session establishment request
message and the session identifier PDU session ID of the PDU
session to the RAN entity.
[0383] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0384] S79. The RAN entity sends the PDU session establishment
request message to the terminal.
[0385] In this step, the PDU session establishment request message
includes the session identifier PDU session ID of the PDU session,
or the RAN entity sends the PDU session establishment request
message and the session identifier PDU session ID of the PDU
session to the terminal.
[0386] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0387] S710a. The terminal sends a PDU session establishment
response message to the RAN entity.
[0388] In this step, the PDU session establishment response message
includes the session identifier PDU session ID of the PDU session,
or the terminal sends the PDU session establishment response
message and the session identifier PDU session ID of the PDU
session to the RAN entity. In this case, the session identifier PDU
session ID of the PDU session is the session identifier allocated
by the SMF entity. In other words, the terminal determines to use
the session identifier allocated by the SMF entity.
[0389] S710b. The RAN entity sends the PDU session establishment
response message to the AMF entity.
[0390] In this step, the PDU session establishment response message
includes the session identifier PDU session ID of the PDU session,
or the RAN entity sends the PDU session establishment response
message and the session identifier PDU session ID of the PDU
session to the AMF entity. In this case, the session identifier PDU
session ID of the PDU session is the session identifier allocated
by the SMF entity.
[0391] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0392] S711. The AMF entity sends the PDU session establishment
response message to the SMF entity.
[0393] In this step, the PDU session establishment response message
includes the session identifier PDU session ID of the PDU session,
or the AMF entity sends the PDU session establishment response
message and the session identifier PDU session ID of the PDU
session to the SMF entity. In this case, the session identifier PDU
session ID of the PDU session is the session identifier allocated
by the SMF entity.
[0394] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0395] S712a. The SMF entity initiates an N4 session establishment
procedure.
[0396] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0397] S712b. The SMF entity sends an SM response message to the
AMF entity.
[0398] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0399] S713. Optionally, the SMF entity sends an IPv6 router
advertisement message to the UPF entity.
[0400] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0401] By now, the PDU session establishment procedure is
completed, and then the UPF entity can send downlink data to the
terminal by using the newly established PDU session. In this
embodiment, the SMF entity allocates the session identifier of the
PDU session. After the terminal receives the session identifier, of
the PDU session, that is allocated by the SMF entity, the terminal
uses the session identifier, of the PDU session, that is allocated
by the SMF entity.
[0402] FIG. 9A and FIG. 9B are a signaling diagram of still yet
another session establishment method according to an embodiment of
this application. As shown in FIG. 9A and FIG. 9B, this embodiment
of this application provides still yet another session
establishment method. The method is specifically described as
follows:
[0403] S81. An SMF entity determines to establish a PDU session for
a terminal, and the SMF entity allocates a session identifier PDU
session ID to the PDU session.
[0404] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0405] S82a. Optionally, the SMF entity sends a subscription data
request message to a UDM entity.
[0406] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0407] S82b. Optionally, the UDM entity sends subscription
information to the SMF entity.
[0408] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0409] S83. The SMF entity completes authorization/authentication
for PDU session establishment.
[0410] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0411] S84. The SMF entity selects a UPF entity.
[0412] In an optional implementation, the SMF entity selects, based
on a broadcast session identifier, a user plane function UPF entity
corresponding to a broadcast session, or the SMF entity selects,
based on a group identifier, a UPF entity corresponding to the
group identifier.
[0413] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0414] S85. Optionally, the SMF entity initiates a PDU-CAN session
establishment procedure.
[0415] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0416] S86a. Optionally, the SMF entity sends a user plane session
request to the selected UPF entity, where the user plane session
request includes user plane forwarding rule information of the PDU
session.
[0417] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0418] S86b. Optionally, the UPF entity sends CN tunnel information
to the SMF entity.
[0419] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0420] S87. The SMF entity sends a PDU session establishment
request message to an AMF entity.
[0421] In this step, the PDU session establishment request message
includes the session identifier PDU session ID of the PDU session,
or the SMF entity sends the PDU session establishment request
message and the session identifier PDU session ID of the PDU
session to the AMF entity.
[0422] In an optional implementation, the PDU session establishment
request message includes session establishment assistance
information of the PDU session. Alternatively, the method provided
in this embodiment further includes: sending, by the SMF entity,
session establishment assistance information of the PDU session to
the terminal.
[0423] The session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0424] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0425] S88. The AMF entity sends the PDU session establishment
request message to a RAN entity.
[0426] In this step, the PDU session establishment request message
includes the session identifier PDU session ID of the PDU session,
or the AMF entity sends the PDU session establishment request
message and the session identifier PDU session ID of the PDU
session to the RAN entity.
[0427] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0428] S89. The RAN entity sends the PDU session establishment
request message to the terminal.
[0429] In this step, the PDU session establishment request message
includes the session identifier PDU session ID of the PDU session,
or the RAN entity sends the PDU session establishment request
message and the session identifier PDU session ID of the PDU
session to the terminal.
[0430] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0431] S810a. The terminal allocates a session identifier to the
PDU session.
[0432] In this step, the terminal receives the session identifier
PDU session ID allocated by the SMF entity to the PDU session, but
the terminal refuses to use the session identifier PDU session ID
allocated by the SMF entity to the PDU session. Then, the terminal
allocates the session identifier PDU session ID' to the PDU
session.
[0433] S810b. The terminal sends a PDU session establishment
response message to the RAN entity.
[0434] In this step, the PDU session establishment response message
includes the session identifier PDU session ID' allocated by the
terminal to the PDU session, or the terminal sends, to the RAN
entity, the session identifier PDU session ID' allocated by the
terminal to the PDU session.
[0435] S810c. The RAN entity sends the PDU session establishment
response message to the AMF entity.
[0436] In this step, the PDU session establishment response message
includes the PDU session ID', or the RAN entity sends the PDU
session establishment response message and the PDU session ID' to
the AMF entity.
[0437] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0438] S811. The AMF entity sends the PDU session establishment
response message to the SMF entity.
[0439] In this step, the PDU session establishment response message
includes the PDU session ID', or the AMF entity sends the PDU
session establishment response message and the PDU session ID' to
the SMF entity.
[0440] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0441] S812a. The SMF entity initiates an N4 session establishment
procedure.
[0442] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0443] S812b. The SMF entity sends an SM response message to the
AMF entity.
[0444] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0445] S813. Optionally, the SMF entity sends an IPv6 router
advertisement message to the UPF entity.
[0446] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0447] By now, the PDU session establishment procedure is
completed, and then the UPF entity can send downlink data to the
terminal by using the newly established PDU session. In this
embodiment, the SMF entity allocates the session identifier of the
PDU session. After the terminal receives the session identifier, of
the PDU session, that is allocated by the SMF entity, the terminal
determines not to use the session identifier, of the PDU session,
that is allocated by the SMF entity, but allocates the session
identifier of the PDU session.
[0448] FIG. 10A and FIG. 10B are a signaling diagram of a further
session establishment method according to an embodiment of this
application. As shown in FIG. 10A and FIG. 10B, this embodiment of
this application provides a further session establishment method.
The method is specifically described as follows:
[0449] S91. An SMF entity determines to establish a PDU session for
a terminal.
[0450] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0451] S92a. Optionally, the SMF entity sends a subscription data
request message to a UDM entity.
[0452] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0453] S92b. Optionally, the UDM entity sends subscription
information to the SMF entity.
[0454] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0455] S93. The SMF entity completes authorization/authentication
for PDU session establishment.
[0456] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0457] S94. The SMF entity selects a UPF entity.
[0458] In an optional implementation, the SMF entity selects, based
on a broadcast session identifier, a user plane function UPF entity
corresponding to a broadcast session, or the SMF entity selects,
based on a group identifier, a UPF entity corresponding to the
group identifier.
[0459] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0460] S95. Optionally, the SMF entity initiates a PDU-CAN session
establishment procedure.
[0461] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0462] S96a. Optionally, the SMF entity sends a user plane session
request to the selected UPF entity, where the user plane session
request includes user plane forwarding rule information of the PDU
session.
[0463] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0464] S96b. Optionally, the UPF entity sends CN tunnel information
to the SMF entity.
[0465] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0466] S97. The SMF entity sends a PDU session establishment
request message to an AMF entity.
[0467] In an optional implementation, the PDU session establishment
request message includes session establishment assistance
information of the PDU session. Alternatively, the method provided
in this embodiment further includes: sending, by the SMF entity,
session establishment assistance information of the PDU session to
the terminal.
[0468] The session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0469] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0470] S98. The AMF entity sends the PDU session establishment
request message to a RAN entity.
[0471] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0472] S99. The RAN entity sends the PDU session establishment
request message to the terminal.
[0473] In an example, for this step, refer to step 101 in FIG. 5.
Details are not described again.
[0474] S910a. The terminal allocates a session identifier to the
PDU session.
[0475] In this step, the terminal does not receive a session
identifier PDU session ID allocated by the SMF entity to the PDU
session, and then the terminal allocates the session identifier PDU
session ID' to the PDU session.
[0476] S910b. The terminal sends a PDU session establishment
response message to the RAN entity.
[0477] In this step, the PDU session establishment response message
includes the session identifier PDU session ID' allocated by the
terminal to the PDU session, or the terminal sends, to the RAN
entity, the session identifier PDU session ID' allocated by the
terminal to the PDU session.
[0478] S910c. The RAN entity sends the PDU session establishment
response message to the AMF entity.
[0479] In this step, the PDU session establishment response message
includes the PDU session ID', or the RAN entity sends the PDU
session establishment response message and the PDU session ID' to
the AMF entity.
[0480] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0481] S911. The AMF entity sends the PDU session establishment
response message to the SMF entity.
[0482] In this step, the PDU session establishment response message
includes the PDU session ID', or the AMF entity sends the PDU
session establishment response message and the PDU session ID' to
the SMF entity.
[0483] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0484] S912a. The SMF entity initiates an N4 session establishment
procedure.
[0485] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0486] S912b. The SMF entity sends an SM response message to the
AMF entity.
[0487] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0488] S913. Optionally, the SMF entity sends an IPv6 router
advertisement message to the UPF entity.
[0489] In an example, for this step, refer to step 102 in FIG. 5.
Details are not described again.
[0490] By now, the PDU session establishment procedure is
completed, and then the UPF entity can send downlink data to the
terminal by using the newly established PDU session. In this
embodiment, the SMF entity does not allocate the session identifier
of the PDU session. After the terminal determines that the terminal
does not receive the session identifier, of the PDU session, that
is sent by the SMF entity, the terminal allocates the session
identifier of the PDU session.
[0491] This application further provides a method and a device for
triggering a PDU session establishment procedure by reporting a
broadcast quality report message by a terminal.
[0492] The prior art further provides a method for triggering PDU
session establishment. The method is described as follows: A
terminal sends a broadcast quality report message to an SMF entity
through an AMF entity, and then the SMF entity sends a broadcast
quality report receive response message to the terminal through the
AMF entity. Then, the steps shown in FIG. 3A to FIG. 3C are
performed.
[0493] FIG. 11 is a flowchart of a still further session
establishment method according to an embodiment of this
application. As shown in FIG. 11, this embodiment of this
application provides a still further session establishment method.
The method is performed by an SMF entity. The method is
specifically described as follows:
[0494] 401. The SMF entity receives a broadcast quality report
message from a terminal, where the broadcast quality report message
is used to request to establish a PDU session.
[0495] In an optional implementation, the broadcast quality report
message includes one or more of the following information: an
identifier of the broadcast quality report message, a PDU session
establishment request message, indication information, and a
session identifier. The indication information is used to request
to establish the PDU session, the session identifier is used to
identify the PDU session, and the PDU session establishment request
message is used to request to establish the PDU session.
[0496] Optionally, the identifier of the broadcast quality report
message is used to indicate a type of the broadcast quality report
message.
[0497] For example, when the terminal does not establish a PDU
session, or when a current PDU session of the terminal is not
allowed for sharing, or when the terminal needs to be switched from
a broadcast path to a unicast path, steps in this embodiment may be
performed.
[0498] First, when the terminal determines that the terminal fails
to receive broadcast data, the terminal sends the broadcast quality
report message to an AMF entity. The broadcast quality report
message is used to request to establish the PDU session.
Optionally, the broadcast quality report message carries broadcast
received quality information. For example, when the terminal
determines that received quality of a broadcast channel signal of
the terminal is less than a preset quality value, the terminal
sends the broadcast quality report message to the SMF entity. The
broadcast received quality information is used to indicate that the
terminal cannot receive data on a broadcast path, or the broadcast
received quality information is used to indicate that the terminal
fails to receive data on a broadcast path, or the broadcast
received quality information is used to indicate that the terminal
listens (listening) to or no longer listens (not listening) to data
on a broadcast path. The broadcast received quality information may
be "good" or "bad", or may be "listening" or "not listening". For
another example, the broadcast received quality information may
alternatively be a specific measurement value of received quality
of a broadcast channel. The identifier of the broadcast quality
report message in the broadcast quality report message represents a
request for establishing the PDU session, or the PDU session
establishment request message in the broadcast quality report
message represents a request for establishing the PDU session, or
the indication information in the broadcast quality report message
represents a request for establishing the PDU session, or the
session identifier of the PDU session in the broadcast quality
report message represents a request for establishing the PDU
session. Alternatively, a combination of at least two of the
identifier of the broadcast quality report message, the PDU session
establishment request message, the indication information, and the
session identifier in the broadcast quality report message
represents a request for establishing the PDU session. The
indication information in the broadcast quality report message may
be implicit indication information, or may be explicit indication
information. For example, a flag or a parameter in the broadcast
quality report message represents the request for establishing the
PDU session.
[0499] Optionally, the identifier of the broadcast quality report
message may be used to indicate a type of the broadcast quality
report message. For example, a plurality of bits are used as the
identifier of the broadcast quality report message during message
encoding. For example, "000" may be used as the identifier of the
broadcast quality report message, and "000" may be used to indicate
that a type of the message is a broadcast quality report
message.
[0500] Then, the AMF entity sends the broadcast quality report
message to the SMF entity.
[0501] 402. The SMF entity performs a PDU session establishment
procedure based on the broadcast quality report message.
[0502] In an optional implementation, step 402 specifically
includes: performing, by the SMF entity, the PDU session
establishment procedure when the SMF entity determines, based on
the broadcast received quality information in the broadcast quality
report message, that the terminal fails to receive data.
[0503] In an optional implementation, if the broadcast quality
report message includes the PDU session establishment request
message, the method provided in this embodiment further includes:
sending, by the SMF entity, a PDU session establishment response
message to the terminal.
[0504] In an optional implementation, the PDU session establishment
response message includes information about a QoS flow
corresponding to the PDU session. Alternatively, the method
provided in this embodiment further includes: sending, by the SMF
entity to the terminal based on the broadcast quality report
message, information about a QoS flow corresponding to the PDU
session. The information about the QoS flow is the same as that
described in the foregoing embodiment, and details are not
described again.
[0505] For example, after the SMF entity receives the broadcast
quality report message, the SMF entity may obtain the broadcast
received quality information in the broadcast quality report
message. Then, the SMF entity determines, based on the broadcast
received quality information in the broadcast quality report
message, whether the terminal can receive data. For example, the
SMF entity determines whether the broadcast received quality
information indicates that the terminal fails to receive data, or
the SMF entity determines whether the broadcast received quality
information indicates that signal received quality of the terminal
is less than a preset quality value. When the SMF entity
determines, based on the broadcast received quality information in
the broadcast quality report message, that the terminal fails to
receive the data, for example, when the SMF entity determines that
the broadcast received quality information indicates that the
terminal fails to receive data, or when the SMF entity determines
that the broadcast received quality information indicates that
signal received quality of the terminal is less than the preset
quality value, the SMF entity may perform the PDU session
establishment procedure.
[0506] Optionally, the PDU session establishment procedure
performed by the SMF entity may include the following steps: The
SMF entity sends a subscription data request message to a UDM
entity. The UDM entity sends subscription information to the SMF
entity. The SMF entity completes authorization/authentication for
PDU session establishment. The SMF entity selects a PCF entity
according to a rule. The SMF entity obtains a PCC rule. The SMF
entity selects a UPF entity. The SMF entity initiates a PDU-CAN
session establishment procedure. The SMF entity initiates an N4
session establishment/modification procedure to the UPF entity. The
UPF entity sends CN tunnel information to the SMF entity. The SMF
entity sends an SM response message to the AMF entity. The AMF
entity sends an N2 PDU session request message to a RAN entity. The
RAN entity sends an RRC connection reconfiguration message to the
terminal. The RAN entity sends an N2 PDU session establishment
response message to the AMF entity. The AMF entity sends an SM
request message to the SMF entity. The SMF entity initiates an N4
session establishment procedure. The SMF entity sends an SM
response message to the AMF entity. The SMF entity sends an IPv6
router advertisement message to the UPF entity. The SMF entity
releases a user plane resource. By now, the PDU session
establishment procedure is completed. For the foregoing steps,
refer to the steps in FIG. 3A to FIG. 3C.
[0507] Optionally, the SMF entity may send, to the terminal, the
information about the QoS flow corresponding to the PDU session.
The SMF entity may send, to the terminal, the information about the
QoS flow corresponding to the PDU session in the following manners:
Manner 1: If the broadcast quality report message received by the
SMF entity includes the PDU session establishment request message,
the SMF entity may send a PDU session establishment response
message to the AMF entity, and the PDU session establishment
response message carries the information about the QoS flow
corresponding to the PDU session. Then, the AMF entity may send, to
the terminal, the PDU session establishment response message that
carries the information about the QoS flow corresponding to the PDU
session. Manner 2: After the SMF entity receives the broadcast
quality report message, the SMF entity directly sends, to the AMF
entity, the information about the QoS flow corresponding to the PDU
session, and then the AMF entity may send, to the terminal, the
information about the QoS flow corresponding to the PDU
session.
[0508] The QoS flow is a finest granularity for data forwarding and
processing in 5G. All data mapped to a same QoS flow uses a same
forwarding and processing policy. The forwarding and processing
policy includes, for example, a schedule policy, a queue management
policy, a data shaping policy, and an RLC configuration policy.
Different QoS flows use different QoS forwarding rules, and
different QoS flows may be identified by using QoS flow
identifiers.
[0509] According to the method provided in the foregoing
embodiment, the SMF entity receives the broadcast quality report
message from the terminal, and the broadcast quality report message
is used to request to establish the PDU session. The SMF entity
performs the PDU session establishment procedure based on the
broadcast quality report message. The broadcast quality report
message reported by the terminal is used to request to establish
the PDU session, and then the SMF entity may directly perform the
PDU session establishment procedure. In this way, a process in
which the terminal reports the broadcast quality report message to
the SMF entity, the SMF entity sends a PDU session establishment
request message to the terminal, and then the terminal performs a
PDU session establishment procedure is not required, or a process
in which an application server sends a device trigger message to
the terminal, and then the terminal actively initiates a PDU
session establishment procedure is not required. These complex
signaling interaction procedures are not required. Therefore,
signaling interaction between the terminal and a network side can
be reduced, a delay of switching from the broadcast path to the
unicast path can be reduced, and the PDU session can be quickly
established.
[0510] FIG. 12 is a flowchart of a yet further session
establishment method according to an embodiment of this
application. As shown in FIG. 12, this embodiment of this
application provides a yet further session establishment method.
The method is performed by a terminal. The method is specifically
described as follows:
[0511] 501. The terminal sends a broadcast quality report message
to an SMF entity, where the broadcast quality report message is
used to request to establish a PDU session.
[0512] In an optional implementation, step 501 specifically
includes: sending the broadcast quality report message to the SMF
entity when the terminal fails to receive data.
[0513] Optionally, the broadcast quality report message includes
broadcast received quality information.
[0514] In an optional implementation, the broadcast quality report
message includes one or more of the following information: an
identifier of the broadcast quality report message, a PDU session
establishment request message, indication information, and a PDU
session identifier. The indication information is used to request
to establish the PDU session, the session identifier is used to
identify the PDU session, and the PDU session establishment request
message is used to request to establish the PDU session.
[0515] In an optional implementation, the method provided in this
embodiment further includes step 502: The terminal receives, from
the SMF entity, information about a QoS flow corresponding to the
PDU session. Alternatively, the broadcast quality report message
includes the PDU session establishment request message, and the
method provided in this embodiment further includes step 503: The
terminal receives a PDU session establishment response message from
the SMF entity.
[0516] Optionally, the PDU session establishment response message
includes the information about the QoS flow corresponding to the
PDU session.
[0517] According to the method provided in the foregoing
embodiment, the terminal sends the broadcast quality report message
to the SMF entity, and the broadcast quality report message is used
to request to establish the PDU session. The SMF entity performs a
PDU session establishment procedure based on the broadcast quality
report message. The broadcast quality report message reported by
the terminal is used to request to establish the PDU session, and
then the SMF entity may directly perform the PDU session
establishment procedure. In this way, a process in which the
terminal reports the broadcast quality report message to the SMF
entity, the SMF entity sends a PDU session establishment request
message to the terminal, and then the terminal performs a PDU
session establishment procedure is not required, or a process in
which an application server sends a device trigger message to the
terminal, and then the terminal actively initiates a PDU session
establishment procedure is not required. These complex signaling
interaction procedures are not required. Therefore, signaling
interaction between the terminal and a network side can be reduced,
a delay of switching from the broadcast path to the unicast path
can be reduced, and the PDU session can be quickly established.
[0518] FIG. 13 is a signaling diagram of a still yet further
session establishment method according to an embodiment of this
application. As shown in FIG. 13, this embodiment of this
application provides a still yet further session establishment
method. The method is specifically described as follows:
[0519] S131. A terminal sends a broadcast quality report message to
an AMF entity, where the broadcast quality report message is used
to request to establish a PDU session.
[0520] In an optional implementation, the broadcast quality report
message includes one or more of the following information: an
identifier of the broadcast quality report message, a PDU session
establishment request message, indication information, and a PDU
session identifier. The indication information is used to request
to establish the PDU session, the session identifier is used to
identify the PDU session, and the PDU session establishment request
message is used to request to establish the PDU session.
[0521] Optionally, the broadcast quality report message includes
broadcast received quality information.
[0522] In an example, for this step, refer to step 401 in FIG. 11.
Details are not described again.
[0523] S132. The AMF entity sends the broadcast quality report
message to an SMF entity.
[0524] In an example, for this step, refer to step 401 in FIG. 11.
Details are not described again.
[0525] S133. The SMF entity performs a PDU session establishment
procedure based on the broadcast quality report message.
[0526] In an example, for this step, refer to step 402 in FIG. 11.
Details are not described again.
[0527] S134. If the broadcast quality report message includes the
PDU session establishment request message, the SMF entity sends a
PDU session establishment response message to the AMF entity, where
the PDU session establishment response message includes information
about a QoS flow corresponding to the PDU session.
[0528] In an example, for this step, refer to step 402 in FIG. 11.
Details are not described again.
[0529] S135. The AMF entity sends the PDU session establishment
response message to the terminal, where the PDU session
establishment response message includes the information about the
QoS flow corresponding to the PDU session.
[0530] In an example, for this step, refer to step 402 in FIG. 11.
Details are not described again.
[0531] FIG. 14 is a signaling diagram of even yet another session
establishment method according to an embodiment of this
application. As shown in FIG. 14, this embodiment of this
application provides even yet another session establishment method.
The method is specifically described as follows:
[0532] S141. A terminal sends a broadcast quality report message to
an AMF entity, where the broadcast quality report message is used
to request to establish a PDU session.
[0533] In an optional implementation, the broadcast quality report
message includes one or more of the following information: an
identifier of the broadcast quality report message, a PDU session
establishment request message, indication information, and a PDU
session identifier. The indication information is used to request
to establish the PDU session, the session identifier is used to
identify the PDU session, and the PDU session establishment request
message is used to request to establish the PDU session.
[0534] Optionally, the broadcast quality report message includes
broadcast received quality information.
[0535] In an example, for this step, refer to step 401 in FIG. 11.
Details are not described again.
[0536] S142. The AMF entity sends the broadcast quality report
message to an SMF entity.
[0537] In an example, for this step, refer to step 401 in FIG. 11.
Details are not described again.
[0538] S143. The SMF entity performs a PDU session establishment
procedure based on the broadcast quality report message.
[0539] In an example, for this step, refer to step 402 in FIG. 11.
Details are not described again.
[0540] S144. The broadcast quality report message includes the PDU
session establishment request message, and the SMF entity sends, to
the AMF entity, a PDU session establishment response message and
information about a QoS flow corresponding to the PDU session.
[0541] In an example, for this step, refer to step 402 in FIG. 11.
Details are not described again.
[0542] S145. The AMF entity sends, to the terminal, the PDU session
establishment response message and the information about the QoS
flow corresponding to the PDU session.
[0543] In an example, for this step, refer to step 402 in FIG. 11.
Details are not described again.
[0544] FIG. 15 is a schematic structural diagram of a session
establishment device according to an embodiment of this
application. As shown in FIG. 15, an embodiment of this application
provides a session establishment device. The session establishment
device may be an SMF entity, or the session establishment device
may be one or more chips, or the session establishment device may
be a system on chip, or the session establishment device may be
another apparatus that can perform an action of the device. The
session establishment device may be configured to perform an action
or a step of the SMF entity in the embodiment shown in FIG. 5. The
session establishment device may be further configured to perform
an action or a step of the SMF entity in the embodiments shown in
FIG. 8A to FIG. 10B. The session establishment device may include a
first sending module 151 and a first receiving module 152.
[0545] The first sending module 151 is configured to send a PDU
session establishment request message to a terminal, where the PDU
session establishment request message is used to request to
establish a PDU session. In this case, the first sending module 151
is configured to support the SMF entity in performing step 101 in
FIG. 5.
[0546] The first receiving module 152 is configured to receive a
PDU session establishment response message from the terminal. In
this case, the first receiving module 152 is configured to support
the SMF entity in performing step 102 in FIG. 5.
[0547] In an optional implementation, the PDU session establishment
response message includes a session identifier of the PDU session.
Alternatively, the device provided in this embodiment further
includes: a second receiving module, configured to receive a
session identifier of the PDU session from the terminal.
[0548] In an optional implementation, the PDU session establishment
request message includes session establishment assistance
information of the PDU session. Alternatively, the device provided
in this embodiment further includes: a second sending module,
configured to send session establishment assistance information of
the PDU session to the terminal. The session establishment
assistance information of the PDU session includes one or more of a
broadcast session identifier and a group identifier, the broadcast
session identifier is used to represent a broadcast session in
which the terminal participates, and the group identifier is used
to represent a group including the terminal.
[0549] In an optional implementation, the PDU session establishment
request message includes the session identifier of the PDU session.
The device provided in this embodiment further includes: an
allocation module, configured to allocate the session identifier to
the PDU session.
[0550] In addition, for principles of the modules in this
embodiment, refer to the descriptions in FIG. 8A to FIG. 10B.
[0551] FIG. 16 is a schematic structural diagram of another session
establishment device according to an embodiment of this
application. As shown in FIG. 16, an embodiment of this application
provides another session establishment device. The session
establishment device may be an SMF entity, or the session
establishment device may be one or more chips, or the session
establishment device may be a system on chip, or the session
establishment device may be another apparatus that can perform an
action of the device. The session establishment device may be
configured to perform an action or a step of the SMF entity in the
embodiment shown in FIG. 5. The session establishment device may be
further configured to perform an action or a step of the SMF entity
in the embodiments shown in FIG. 8A to FIG. 10B. Based on the
session establishment device shown in FIG. 15, the session
establishment device provided in this embodiment may include:
[0552] a first selection module 161, configured to: select, based
on the broadcast session identifier, a user plane function UPF
entity corresponding to the broadcast session, and send a user
plane session request to the UPF entity corresponding to the
broadcast session; or
[0553] a second selection module 162, configured to: select, based
on the group identifier, a UPF entity corresponding to the group
identifier, and send a user plane session request to the UPF entity
corresponding to the group identifier.
[0554] The user plane session request includes user plane
forwarding rule information of the PDU session.
[0555] The first selection module 161 or the second selection
module 162 is configured to support the SMF entity in performing
step S74 in FIG. 8A and FIG. 8B, or performing step S84 in FIG. 9A
and FIG. 9B, or performing step S94 in FIG. 10A and FIG. 10B.
[0556] The first selection module 161 or the second selection
module 162 may perform a corresponding step prior to or next to
either of the first sending module 151 and the first receiving
module 152. Further, the first selection module 161 or the second
selection module 162 may be connected to either of the first
sending module 151 and the first receiving module 152 in another
connection manner, and a connection manner is not limited to the
connection manner shown in FIG. 16.
[0557] According to the SMF entity provided in the foregoing
embodiment, the SMF entity sends the PDU session establishment
request message to the terminal, where the PDU session
establishment request message is used to request to establish the
PDU session. The SMF entity receives the PDU session establishment
response message from the terminal. Optionally, the PDU session
establishment response message includes the session identifier of
the PDU session, or the SMF entity receives the session identifier
of the PDU session from the terminal. Optionally, the SMF entity
allocates the session identifier to the PDU session, and the PDU
session establishment request message includes the session
identifier of the PDU session. Therefore, a method for actively
initiating the PDU session establishment procedure on a network
side is provided. When the terminal needs to be switched from a
broadcast path to a unicast path, the PDU session may be
established for the terminal on the network side, to establish the
unicast path. In addition, because it can be ensured that a same
UPF entity is selected by a broadcast session for the broadcast
path and is selected by a unicast session for the unicast path on
the network side, it can be ensured that user plane data is
consistent and synchronized on the broadcast path and the unicast
path when the user plane data is switched from the broadcast path
to the unicast path. Negotiation performed when user plane downlink
data is switched from the broadcast path to the unicast path is
avoided, so that a delay of switching from the broadcast session to
the unicast session can be reduced, to ensure fast and continuous
switching of data, and ensure fast switching that meets service
continuity requirements of a broadcast mode and a unicast mode. In
addition, the network side triggers the terminal to establish the
PDU session, and this can reduce signaling interaction in a process
in which the terminal establishes the PDU session with the network
side, and further reduce a delay.
[0558] FIG. 17 is a schematic structural diagram of still another
session establishment device according to an embodiment of this
application. As shown in FIG. 17, an embodiment of this application
provides still another session establishment device. The session
establishment device may be a terminal, or the session
establishment device may be one or more chips, or the session
establishment device may be a system on chip, or the session
establishment device may be another apparatus that can perform an
action of the device. The session establishment device may be
configured to perform an action or a step of the terminal in the
embodiment shown in FIG. 6. The session establishment device may be
further configured to perform an action or a step of the terminal
in the embodiments shown in FIG. 8A to FIG. 10B. The session
establishment device may include a receiving module 171 and a first
sending module 172.
[0559] The receiving module 171 is configured to receive a PDU
session establishment request message from an SMF entity, where the
PDU session establishment request message is used to request to
establish a PDU session. In this case, the receiving module 171 is
configured to support the terminal in performing step 201 in FIG.
6.
[0560] The first sending module 172 is configured to send a PDU
session establishment response message to the SMF entity based on
the PDU session establishment request message. In this case, the
first sending module 172 is configured to support the terminal in
performing step 202 in FIG. 6.
[0561] In an optional implementation, the PDU session establishment
response message includes a session identifier of the PDU session.
Alternatively, the device provided in this embodiment further
includes: a second sending module, configured to send a session
identifier of the PDU session to the SMF entity.
[0562] In an optional implementation, the PDU session establishment
request message includes the session identifier of the PDU
session.
[0563] In an optional implementation, the device provided in this
embodiment further includes an allocation module, configured to
allocate the session identifier to the PDU session based on the PDU
session establishment request message. In this case, the allocation
module is configured to support the terminal in performing step 203
in FIG. 6.
[0564] In addition, for principles of the modules in this
embodiment, refer to the descriptions in FIG. 8A to FIG. 10B.
[0565] FIG. 18 is a schematic structural diagram of yet another
session establishment device according to an embodiment of this
application. As shown in FIG. 18, an embodiment of this application
provides yet another session establishment device. The session
establishment device may be a terminal, or the session
establishment device may be one or more chips, or the session
establishment device may be a system on chip, or the session
establishment device may be another apparatus that can perform an
action of the device. The session establishment device may be
configured to perform an action or a step of the terminal in the
embodiment shown in FIG. 6. The session establishment device may be
further configured to perform an action or a step of the terminal
in the embodiments shown in FIG. 8A to FIG. 10B. Based on the
session establishment device shown in FIG. 17, in the session
establishment device provided in this embodiment,
[0566] the PDU session establishment request message includes
session establishment assistance information of the PDU session,
and the device provided in this embodiment further includes: a
first obtaining module 181, configured to obtain, based on the
session establishment assistance information of the PDU session,
information about a QoS flow corresponding to the PDU session. In
this case, the first obtaining module 181 needs to perform a
corresponding step next to the receiving module 171.
[0567] Alternatively, the device provided in this embodiment
further includes: a second obtaining module 182, configured to
receive session establishment assistance information of the PDU
session from the SMF entity, and obtain, based on the session
establishment assistance information of the PDU session,
information about a QoS flow corresponding to the PDU session. The
second obtaining module 182 may perform a corresponding step prior
to or next to either of the receiving module 171 and the first
sending module 172.
[0568] The session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0569] In addition, for principles of the modules in this
embodiment, refer to the descriptions in FIG. 6 and FIG. 8A to FIG.
10B.
[0570] According to the terminal provided in the foregoing
embodiments, the terminal receives the PDU session establishment
request message from the SMF entity, and the PDU session
establishment request message is used to request to establish the
PDU session. The terminal sends the PDU session establishment
response message to the SMF entity. Optionally, the PDU session
establishment response message includes the session identifier of
the PDU session, or the SMF entity receives the session identifier
of the PDU session from the terminal. Optionally, the SMF entity
allocates the session identifier to the PDU session, and the PDU
session establishment request message includes the session
identifier of the PDU session. Therefore, a method for actively
initiating the PDU session establishment procedure on a network
side is provided. When the terminal needs to be switched from a
broadcast path to the unicast path, the PDU session may be
established for the terminal on the network side, to establish the
unicast path. In addition, because it can be ensured that a same
UPF entity is selected by the broadcast session for the broadcast
path and is selected by the unicast session for the unicast path on
the network side, it can be ensured that user plane data is
consistent and synchronized on the broadcast path and the unicast
path when the user plane data is switched from the broadcast path
to the unicast path. Negotiation performed when user plane downlink
data is switched from the broadcast path to the unicast path is
avoided, so that a delay of switching from the broadcast path to
the unicast path can be reduced, to ensure fast and continuous
switching of data, and ensure fast switching that meets service
continuity requirements of a broadcast mode and a unicast mode. In
addition, the network side triggers the terminal to establish the
PDU session, and this can reduce signaling interaction in a process
in which the terminal establishes the PDU session with the network
side, and further reduce a delay.
[0571] FIG. 19 is a schematic structural diagram of still yet
another session establishment device according to an embodiment of
this application. As shown in FIG. 19, an embodiment of this
application provides still yet another session establishment
device. The session establishment device may be an AMF entity, or
the session establishment device may be one or more chips, or the
session establishment device may be a system on chip, or the
session establishment device may be another apparatus that can
perform an action of the device. The session establishment device
may be configured to perform an action or a step of the AMF entity
in the embodiment shown in FIG. 7. The session establishment device
may be further configured to perform an action or a step of the AMF
entity in the embodiments shown in FIG. 8A to FIG. 10B. The session
establishment device may include a first receiving module 191, a
first sending module 192, a second receiving module 193, and a
second sending module 194.
[0572] The first receiving module 191 is configured to receive a
PDU session request message from an SMF entity, where the PDU
session establishment request message is used to request to
establish a PDU session. In this case, the first receiving module
191 is configured to support the AMF entity in performing step 301
in FIG. 7.
[0573] The first sending module 192 is configured to send the PDU
session request message to a terminal. In this case, the first
sending module 192 is configured to support the AMF entity in
performing step 302 in FIG. 7.
[0574] The second receiving module 193 is configured to receive a
PDU session establishment response message from the terminal. In
this case, the second receiving module 193 is configured to support
the AMF entity in performing step 303 in FIG. 7.
[0575] The second sending module 194 is configured to send the PDU
session establishment response message to the SMF entity. In this
case, the second sending module 194 is configured to support the
AMF entity in performing step 304 in FIG. 7.
[0576] In addition, for principles of the modules in this
embodiment, refer to the descriptions in FIG. 8A to FIG. 10B.
[0577] FIG. 20 is a schematic structural diagram of a further
session establishment device according to an embodiment of this
application. As shown in FIG. 20, an embodiment of this application
provides a further session establishment device. The session
establishment device may be an AMF entity, or the session
establishment device may be one or more chips, or the session
establishment device may be a system on chip, or the session
establishment device may be another apparatus that can perform an
action of the device. The session establishment device may be
configured to perform an action or a step of the AMF entity in the
embodiment shown in FIG. 7. The session establishment device may be
further configured to perform an action or a step of the AMF entity
in the embodiments shown in FIG. 8A to FIG. 10B. Based on the
session establishment device shown in FIG. 19, in the session
establishment device provided in this embodiment,
[0578] the PDU session establishment request message includes
session establishment assistance information of the PDU session, or
the device further includes a third receiving module, configured to
receive session establishment assistance information of the PDU
session from the SMF entity.
[0579] The session establishment assistance information of the PDU
session includes one or more of a broadcast session identifier and
a group identifier, the broadcast session identifier is used to
represent a broadcast session in which the terminal participates,
and the group identifier is used to represent a group including the
terminal.
[0580] The first sending module 192 includes:
[0581] a first selection submodule 1921, configured to select a
radio access network function RAN entity based on the session
establishment assistance information of the PDU session; and
[0582] a first sending submodule 1922, configured to send the PDU
session request message to the terminal through the RAN entity.
[0583] In this case, the first sending module 192 is configured to
support the AMF entity in performing the first implementation of
step 302 in FIG. 7.
[0584] FIG. 21 is a schematic structural diagram of a still further
session establishment device according to an embodiment of this
application. As shown in FIG. 21, an embodiment of this application
provides a still further session establishment device. The session
establishment device may be an AMF entity, or the session
establishment device may be one or more chips, or the session
establishment device may be a system on chip, or the session
establishment device may be another apparatus that can perform an
action of the device. The session establishment device may be
configured to perform an action or a step of the AMF entity in the
embodiment shown in FIG. 7. The session establishment device may be
further configured to perform an action or a step of the AMF entity
in the embodiments shown in FIG. 8A to FIG. 10B. Based on the
session establishment device shown in FIG. 19, in the session
establishment device provided in this embodiment,
[0585] the PDU session request message includes an identifier of
the terminal, or the device further includes a fourth receiving
module, configured to receive an identifier of the terminal from
the SMF entity.
[0586] The first sending module 192 includes:
[0587] a second selection submodule 1923, configured to select a
RAN entity based on the identifier of the terminal; and
[0588] a second sending submodule 1924, configured to send the PDU
session request message to the terminal through the RAN entity.
[0589] In this case, the first sending module 192 is configured to
support the AMF entity in performing the second implementation of
step 302 in FIG. 7.
[0590] According to the AMF entity provided in the foregoing
embodiments, the AMF entity receives the PDU session request
message from the SMF entity, where the PDU session establishment
request message is used to request to establish the PDU session.
The AMF entity sends the PDU session request message to the
terminal. The AMF entity receives the PDU session establishment
response message from the terminal, and sends the PDU session
establishment response message to the SMF entity. Optionally, the
PDU session establishment response message includes a session
identifier of the PDU session, or the SMF entity receives a session
identifier of the PDU session from the terminal. Optionally, the
SMF entity allocates a session identifier to the PDU session, and
the PDU session establishment request message includes the session
identifier of the PDU session. Therefore, a method for actively
initiating the PDU session establishment procedure on a network
side is provided. When the terminal needs to be switched from a
broadcast path to the unicast path, the PDU session may be
established for the terminal on the network side, to establish the
unicast path. In addition, because it can be ensured that a same
UPF entity is selected by the broadcast session for the broadcast
path and is selected by the unicast session for the unicast path on
the network side, it can be ensured that user plane data is
consistent and synchronized on the broadcast path and the unicast
path when the user plane data is switched from the broadcast path
to the unicast path. Negotiation performed when user plane downlink
data is switched from the broadcast path to the unicast path is
avoided, so that a delay of switching from the broadcast path to
the unicast path can be reduced, to ensure fast and continuous
switching of data, and ensure fast switching that meets service
continuity requirements of a broadcast mode and a unicast mode. In
addition, the network side triggers the terminal to establish the
PDU session, and this can reduce signaling interaction in a process
in which the terminal establishes the PDU session with the network
side, and further reduce a delay.
[0591] FIG. 22 is a schematic structural diagram of a yet further
session establishment device according to an embodiment of this
application. As shown in FIG. 22, an embodiment of this application
provides a yet further session establishment device. The session
establishment device may be an SMF entity, or the session
establishment device may be one or more chips, or the session
establishment device may be a system on chip, or the session
establishment device may be another apparatus that can perform an
action of the device. The session establishment device may be
configured to perform an action or a step of the SMF entity in the
embodiment shown in FIG. 11. The session establishment device may
be further configured to perform an action or a step of the SMF
entity in the embodiments shown in FIG. 13 and FIG. 14. The session
establishment device may include a receiving module 221 and an
execution module 222.
[0592] The receiving module 221 is configured to receive a
broadcast quality report message from a terminal, where the
broadcast quality report message is used to request to establish a
PDU session. In this case, the receiving module 221 is configured
to support the SMF entity in performing step 401 in FIG. 11.
[0593] The execution module 222 is configured to perform a PDU
session establishment procedure based on the broadcast quality
report message. In this case, the execution module 222 is
configured to support the SMF entity in performing step 402 in FIG.
11.
[0594] In an optional implementation, the broadcast quality report
message includes one or more of the following information: an
identifier of the broadcast quality report message, a PDU session
establishment request message, indication information, and a
session identifier. The indication information is used to request
to establish the PDU session, the session identifier is used to
identify the PDU session, and the PDU session establishment request
message is used to request to establish the PDU session.
[0595] Optionally, the broadcast quality report message includes
broadcast received quality information.
[0596] In an optional implementation, the execution module 222 is
specifically configured to: perform the PDU session establishment
procedure when it is determined, based on the broadcast received
quality information in the broadcast quality report message, that
the terminal fails to receive data.
[0597] In addition, for principles of the modules in this
embodiment, refer to the descriptions in FIG. 13 and FIG. 14.
[0598] FIG. 23 is a schematic structural diagram of a still yet
further session establishment device according to an embodiment of
this application. As shown in FIG. 23, an embodiment of this
application provides a still yet further session establishment
device. The session establishment device may be an SMF entity, or
the session establishment device may be one or more chips, or the
session establishment device may be a system on chip, or the
session establishment device may be another apparatus that can
perform an action of the device. The session establishment device
may be configured to perform an action or a step of the SMF entity
in the embodiment shown in FIG. 11. The session establishment
device may be further configured to perform an action or a step of
the SMF entity in the embodiments shown in FIG. 13 and FIG. 14.
Based on the session establishment device shown in FIG. 22, in the
session establishment device provided in this embodiment,
[0599] the broadcast quality report message includes the PDU
session establishment request message, and the device further
includes a first sending module 231, configured to send a PDU
session establishment response message to the terminal. The first
sending module 231 may perform a corresponding step next to the
receiving module 221.
[0600] In an optional implementation, the PDU session establishment
response message includes information about a QoS flow
corresponding to the PDU session. Alternatively, the device
provided in this embodiment further includes: a second sending
module, configured to: send, to the terminal based on the broadcast
quality report message, information about a QoS flow corresponding
to the PDU session.
[0601] In addition, for principles of the modules in this
embodiment, refer to the descriptions in FIG. 13 and FIG. 14.
[0602] According to the SMF entity provided in the foregoing
embodiments, the SMF entity receives the broadcast quality report
message from the terminal, and the broadcast quality report message
is used to request to establish the PDU session. The SMF entity
performs the PDU session establishment procedure based on the
broadcast quality report message. The broadcast quality report
message reported by the terminal is used to request to establish
the PDU session, and then the SMF entity may directly perform the
PDU session establishment procedure. In this way, a process in
which the terminal reports the broadcast quality report message to
the SMF entity, the SMF entity sends a PDU session establishment
request message to the terminal, and then the terminal performs the
PDU session establishment procedure is not required, or a process
in which an application server triggers a device trigger message to
the terminal, and then the terminal actively initiates the PDU
session establishment procedure is not required. These complex
signaling interaction procedures are not required. Therefore,
signaling interaction between the terminal and a network side can
be reduced, a delay of switching from the broadcast path to the
unicast path can be reduced, and the PDU session can be quickly
established.
[0603] FIG. 24 is a schematic structural diagram of even yet
another session establishment device according to an embodiment of
this application. As shown in FIG. 24, an embodiment of this
application provides even yet another session establishment device.
The session establishment device may be a terminal, or the session
establishment device may be one or more chips, or the session
establishment device may be a system on chip, or the session
establishment device may be another apparatus that can perform an
action of the device. The session establishment device may be
configured to perform an action or a step of the terminal in the
embodiment shown in FIG. 12. The session establishment device may
be further configured to perform an action or a step of the
terminal in the embodiments shown in FIG. 13 and FIG. 14. The
session establishment device may include:
[0604] a sending module 241, configured to send a broadcast quality
report message to an SMF entity, where the broadcast quality report
message is used to request to establish a PDU session. In this
case, the sending module 241 is configured to support the terminal
in performing step 501 in FIG. 12.
[0605] In an optional implementation, the sending module 241 is
specifically configured to send the broadcast quality report
message to the SMF entity when it is determined that data fails to
be received.
[0606] In an optional implementation, the broadcast quality report
message includes one or more of the following information: an
identifier of the broadcast quality report message, a PDU session
establishment request message, indication information, and a PDU
session identifier. The indication information is used to request
to establish the PDU session, the session identifier is used to
identify the PDU session, and the PDU session establishment request
message is used to request to establish the PDU session.
[0607] Optionally, the broadcast quality report message includes
broadcast received quality information.
[0608] In addition, for principles of the modules in this
embodiment, refer to the descriptions in FIG. 13 and FIG. 14.
[0609] FIG. 25 is a schematic structural diagram of even yet
another session establishment device according to an embodiment of
this application. As shown in FIG. 25, an embodiment of this
application provides even yet another session establishment device.
The session establishment device may be a terminal, or the session
establishment device may be one or more chips, or the session
establishment device may be a system on chip, or the session
establishment device may be another apparatus that can perform an
action of the device. The session establishment device may be
configured to perform an action or a step of the terminal in the
embodiment shown in FIG. 12. The session establishment device may
be further configured to perform an action or a step of the
terminal in the embodiments shown in FIG. 13 and FIG. 14. Based on
the session establishment device shown in FIG. 24, the session
establishment device provided in this embodiment further
includes:
[0610] a first receiving module 251, configured to receive, from
the SMF entity, information about a QoS flow corresponding to the
PDU session. The first receiving module 251 may perform a
corresponding step next to the sending module 241. The first
receiving module 251 is configured to support the terminal in
performing step 502 in the embodiment provided in FIG. 12.
[0611] FIG. 26 is a schematic structural diagram of even yet
another session establishment device according to an embodiment of
this application. As shown in FIG. 26, an embodiment of this
application provides even yet another session establishment device.
The session establishment device may be a terminal, or the session
establishment device may be one or more chips, or the session
establishment device may be a system on chip, or the session
establishment device may be another apparatus that can perform an
action of the device. The session establishment device may be
configured to perform an action or a step of the terminal in the
embodiment shown in FIG. 12. The session establishment device may
be further configured to perform an action or a step of the
terminal in the embodiments shown in FIG. 13 and FIG. 14. Based on
the session establishment device provided in FIG. 24, in the
session establishment device provided in this embodiment, the
broadcast quality report message includes the PDU session
establishment request message.
[0612] The device provided in this embodiment further includes a
second receiving module 261, configured to receive a PDU session
establishment response message from the SMF entity. Optionally, the
PDU session establishment response message includes information
about a QoS flow corresponding to the PDU session. The second
receiving module 261 may perform a corresponding step next to the
sending module 241. The second receiving module 261 is configured
to support the terminal in performing step 503 in the embodiment
provided in FIG. 12.
[0613] According to the terminal provided in the foregoing
embodiments, the terminal sends the broadcast quality report
message to the SMF entity, and the broadcast quality report message
is used to request to establish the PDU session. The SMF entity
performs a PDU session establishment procedure based on the
broadcast quality report message. The broadcast quality report
message reported by the terminal is used to request to establish
the PDU session, and then the SMF entity may directly perform the
PDU session establishment procedure. In this way, a process in
which the terminal reports the broadcast quality report message to
the SMF entity, the SMF entity sends a PDU session establishment
request message to the terminal, and then the terminal performs the
PDU session establishment procedure is not required, or a process
in which an application server triggers a device trigger message to
the terminal, and then the terminal actively initiates the PDU
session establishment procedure is not required. These complex
signaling interaction procedures are not required. Therefore,
signaling interaction between the terminal and a network side can
be reduced, a delay of switching from the broadcast path to the
unicast path can be reduced, and the PDU session can be quickly
established.
[0614] FIG. 27 is a schematic structural diagram of an SMF entity
according to an embodiment of this application. As shown in FIG.
27, an embodiment of this application provides an SMF entity. The
SMF entity may be configured to perform an action or a step of the
SMF entity in the embodiment shown in FIG. 5, or may be configured
to perform an action or a step of the SMF entity in the embodiments
shown in FIG. 8A to FIG. 10B, or may be configured to perform an
action or a step of the modules in the device in the embodiments
shown in FIG. 15 and FIG. 16, and specifically includes a processor
2701, a memory 2702, and a communications interface 2703.
[0615] The memory 2702 is configured to store a computer
program.
[0616] The processor 2701 is configured to execute the computer
program stored in the memory 2702, to implement an action of the
SMF entity in the embodiment shown in FIG. 5, an action of the SMF
entity in the embodiments shown in FIG. 8A to FIG. 10B, or an
action of the modules of the device in the embodiments shown in
FIG. 15 and FIG. 16. Details are not described again.
[0617] Optionally, the SMF entity may further include a bus 2704.
For example, the processor 2701, the memory 2702, and the
communications interface 2703 may be connected to each other by
using the bus 2704. The bus 2704 may be a peripheral component
interconnect (peripheral component interconnect, PCI) bus, an
extended industry standard architecture (extended industry standard
architecture, EISA) bus, or the like. The bus 2704 may be
classified into an address bus, a data bus, a control bus, and the
like. For ease of representation, only one thick line is used to
represent the bus in FIG. 27, but this does not mean that there is
only one bus or only one type of bus.
[0618] In the embodiments of this application, reference may be
made to each other for the foregoing embodiments. Same or similar
steps and nouns are not described one by one again.
[0619] Alternatively, some or all of the foregoing modules may be
implemented in a form of an integrated circuit that is embedded in
a chip of the SMF entity. In addition, the modules may be
separately implemented, or may be integrated together. The
foregoing modules may be configured as one or more integrated
circuits for implementing the foregoing methods, for example, one
or more application-specific integrated circuits (Application
Specific Integrated Circuit, ASIC), one or more microprocessors
(digital signal processor, DSP), or one or more field programmable
gate arrays (Field Programmable Gate Array, FPGA).
[0620] FIG. 28 is a schematic structural diagram of a terminal
device according to an embodiment of this application. As shown in
FIG. 28, an embodiment of this application provides a terminal
device. The terminal device may be configured to perform an action
or a step of the terminal device in the embodiment shown in FIG. 6,
or may be configured to perform an action or a step of the terminal
device in the embodiments shown in FIG. 8A to FIG. 10B, or may be
configured to perform an action or a step of the modules in the
device in the embodiments shown in FIG. 17 and FIG. 18, and
specifically includes a processor 2801, a memory 2802, a receiver
2803, and a transmitter 2804. The receiver 2803 and the transmitter
2804 may be connected to an antenna. In a downlink direction, the
receiver 2803 receives, through the antenna, information sent by a
network device, and the transmitter 2804 sends the information to
the processor 2801 for processing. In an uplink direction, the
processor 2801 processes information from the terminal, and
transmits the information to the network device through the
transmitter 2804.
[0621] The memory 2802 is configured to store a computer
program.
[0622] The processor 2801 is configured to execute the computer
program stored in the memory 2802, to implement an action of the
terminal in the embodiment shown in FIG. 6, an action of the
terminal in the embodiments shown in FIG. 8A to FIG. 10B, or an
action of the modules of the device in the embodiments shown in
FIG. 17 and FIG. 18. Details are not described again.
[0623] Optionally, the terminal device may further include a bus
2805. The processor 2801, the memory 2802, the receiver 2803, and
the transmitter 2804 may be connected to each other through the bus
2805. The bus 2805 may be a PCI bus, an EISA bus, or the like. The
bus 2805 may be classified into an address bus, a data bus, a
control bus, and the like. For ease of representation, only one
thick line is used to represent the bus 2805 in FIG. 28, but this
does not mean that there is only one bus or only one type of
bus.
[0624] In the embodiments of this application, reference may be
made to each other for the foregoing embodiments. Same or similar
steps and nouns are not described one by one again.
[0625] Alternatively, some or all of the foregoing modules may be
implemented in a form of an integrated circuit that is embedded in
a chip of the terminal device. In addition, the modules may be
separately implemented, or may be integrated together. To be
specific, the foregoing modules may be one or more integrated
circuits, for example, one or more ASICs, one or more DSPs, or one
or more FPGAs, configured to implement the foregoing methods.
[0626] FIG. 29 is a schematic structural diagram of an AMF entity
according to an embodiment of this application. As shown in FIG.
29, an embodiment of this application provides an AMF entity. The
AMF entity may be configured to perform an action or a step of the
AMF entity in the embodiment shown in FIG. 7, or may be configured
to perform an action or a step of the AMF entity in the embodiments
shown in FIG. 8A to FIG. 10B, or may be configured to perform an
action or a step of the modules in the device in the embodiments
shown in FIG. 19 to FIG. 21, and specifically includes a processor
2901, a memory 2902, and a communications interface 2903.
[0627] The memory 2902 is configured to store a computer
program.
[0628] The processor 2901 is configured to execute the computer
program stored in the memory 2902, to implement an action of the
AMF entity in the embodiment shown in FIG. 7, an action of the AMF
entity in the embodiments shown in FIG. 8A to FIG. 10B, or an
action of the modules of the device in the embodiments shown in
FIG. 19 to FIG. 21. Details are not described again.
[0629] Optionally, the AMF entity may further include a bus 2904.
The processor 2901, the memory 2902, and the communications
interface 2903 may be connected to each other through the bus 2904.
The bus 2904 may be a PCI bus, an EISA bus, or the like. The bus
2904 may be classified into an address bus, a data bus, a control
bus, and the like. For ease of representation, only one thick line
is used to represent the bus in FIG. 29, but this does not mean
that there is only one bus or only one type of bus.
[0630] In the embodiments of this application, reference may be
made to each other for the foregoing embodiments. Same or similar
steps and nouns are not described one by one again.
[0631] Alternatively, some or all of the foregoing modules may be
implemented in a form of an integrated circuit that is embedded in
a chip of the AMF entity. In addition, the modules may be
separately implemented, or may be integrated together. To be
specific, the foregoing modules may be one or more integrated
circuits, for example, one or more ASICs, one or more DSPs, or one
or more FPGAs, configured to implement the foregoing methods.
[0632] FIG. 30 is a schematic structural diagram of another SMF
entity according to an embodiment of this application. As shown in
FIG. 30, an embodiment of this application provides another SMF
entity. The SMF entity may be configured to perform an action or a
step of the SMF entity in the embodiment shown in FIG. 11, or may
be configured to perform an action or a step of the SMF entity in
the embodiments shown in FIG. 13 and FIG. 14, or may be configured
to perform an action or a step of the modules in the device in the
embodiments shown in FIG. 22 and FIG. 23, and specifically includes
a processor 3001, a memory 3002, and a communications interface
3003.
[0633] The memory 3002 is configured to store a computer
program.
[0634] The processor 3001 is configured to execute the computer
program stored in the memory 3002, to implement an action of the
SMF entity in the embodiment shown in FIG. 11, an action of the SMF
entity in the embodiments shown in FIG. 13 and FIG. 14, or an
action of the modules of the device in the embodiments shown in
FIG. 22 and FIG. 23. Details are not described again.
[0635] Optionally, the SMF entity may further include a bus 3004.
The processor 3001, the memory 3002, and the communications
interface 3003 may be connected to each other through the bus 3004.
The bus 3004 may be a PCI bus, an EISA bus, or the like. The bus
3004 may be classified into an address bus, a data bus, a control
bus, and the like. For ease of representation, only one thick line
is used to represent the bus in FIG. 30, but this does not mean
that there is only one bus or only one type of bus.
[0636] In the embodiments of this application, reference may be
made to each other for the foregoing embodiments. Same or similar
steps and nouns are not described one by one again.
[0637] Alternatively, some or all of the foregoing modules may be
implemented in a form of an integrated circuit that is embedded in
a chip of the SMF entity. In addition, the modules may be
separately implemented, or may be integrated together. To be
specific, the foregoing modules may be one or more integrated
circuits, for example, one or more ASICs, one or more DSPs, or one
or more FPGAs, configured to implement the foregoing methods.
[0638] FIG. 31 is a schematic structural diagram of another
terminal device according to an embodiment of this application. As
shown in FIG. 31, an embodiment of this application provides
another terminal device. The terminal device may be configured to
perform an action or a step of the terminal device in the
embodiment shown in FIG. 12, or may be configured to perform an
action or a step of the terminal device in the embodiments shown in
FIG. 13 and FIG. 14, or may be configured to perform an action or a
step of the modules in the device in the embodiments shown in FIG.
24 to FIG. 26, and specifically includes a processor 3101, a memory
3102, a receiver 3103, and a transmitter 3104. The receiver 3103
and the transmitter 3104 may be connected to an antenna. In a
downlink direction, the receiver 3103 receives, through the
antenna, information sent by a network device, and the transmitter
3104 sends the information to the processor 3101 for processing. In
an uplink direction, the processor 3101 processes information from
the terminal, and transmits the information to the network device
through the transmitter 3104.
[0639] The memory 3102 is configured to store a computer
program.
[0640] The processor 3101 is configured to execute the computer
program stored in the memory 3102, to implement an action of the
terminal in the embodiment shown in FIG. 12, an action of the
terminal in the embodiments shown in FIG. 13 and FIG. 14, or an
action of the modules of the device in the embodiments shown in
FIG. 24 to FIG. 26. Details are not described again.
[0641] Optionally, the terminal device may further include a bus
3105. The processor 3101, the memory 3102, the receiver 3103, and
the transmitter 3104 may be connected to each other through the bus
3105. The bus 3105 may be a PCI bus, an EISA bus, or the like. The
bus 3105 may be classified into an address bus, a data bus, a
control bus, and the like. For ease of representation, only one
thick line is used to represent the bus 3105 in FIG. 31, but this
does not mean that there is only one bus or only one type of
bus.
[0642] In the embodiments of this application, reference may be
made to each other for the foregoing embodiments. Same or similar
steps and nouns are not described one by one again.
[0643] Alternatively, some or all of the foregoing modules may be
implemented in a form of an integrated circuit that is embedded in
a chip of the terminal device. In addition, the modules may be
separately implemented, or may be integrated together. To be
specific, the foregoing modules may be one or more integrated
circuits, for example, one or more ASICs, one or more DSPs, or one
or more FPGAs, configured to implement the foregoing methods.
[0644] An embodiment of this application provides a communications
system. The communications system includes the session
establishment device provided in FIG. 15 and FIG. 16, the session
establishment device provided in FIG. 17 and FIG. 18, and the
session establishment device provided in FIG. 19 to FIG. 21.
[0645] An embodiment of this application provides another
communications system. The communications system includes the
session establishment device provided in FIG. 22 to FIG. 23 and the
session establishment device provided in FIG. 24 to FIG. 26.
[0646] All or some of the foregoing embodiments may be implemented
by using software, hardware, firmware, or any combination thereof.
When software is used to implement the embodiments, the embodiments
may be implemented completely or partially in a form of a computer
program product. The computer program product includes one or more
computer instructions. When the computer program instructions are
loaded and executed on the computer, the procedure or functions
according to the embodiments of this application are all or
partially generated. The computer may be a general-purpose
computer, a dedicated computer, a computer network, or other
programmable apparatuses. The computer instructions may be stored
in a computer readable storage medium or may be transmitted from a
computer readable storage medium to another computer readable
storage medium. For example, the computer instructions may be
transmitted from a website, computer, server, or data center to
another website, computer, server, or data center in a wired (for
example, a coaxial cable, an optical fiber, or a digital subscriber
line (digital subscriber line, DSL)) or wireless (for example,
infrared, radio, and microwave, or the like) manner. The computer
storage medium may be any usable medium accessible by a computer,
or a data storage device, such as a server or a data center,
integrating one or more usable media. The usable medium may be a
magnetic medium (for example, a floppy disk, a hard disk, or a
magnetic tape), an optical medium (for example, DVD), a
semiconductor medium (for example, a solid-state drive (solid state
disk, SSD)), or the like.
[0647] A person skilled in the art should be aware that in the
foregoing one or more examples, functions described in the
embodiments of this application may be implemented by hardware,
software, firmware, or any combination thereof. When the present
invention is implemented by software, the foregoing functions may
be stored in a computer readable medium or transmitted as one or
more instructions or code in the computer readable medium. The
computer readable medium includes a computer storage medium and a
communications medium, and the communications medium includes any
medium that enables a computer program to be transmitted from one
place to another. The storage medium may be any available medium
accessible to a general-purpose or dedicated computer.
* * * * *