U.S. patent application number 14/102894 was filed with the patent office on 2014-07-17 for handling user plane congestion.
This patent application is currently assigned to Intel IP Corporation. The applicant listed for this patent is Intel IP Corporation. Invention is credited to Puneet K. Jain, Chang Hong Shan, Eric Siow, Muthaiah Venkatachalam.
Application Number | 20140198637 14/102894 |
Document ID | / |
Family ID | 51165025 |
Filed Date | 2014-07-17 |
United States Patent
Application |
20140198637 |
Kind Code |
A1 |
Shan; Chang Hong ; et
al. |
July 17, 2014 |
Handling User Plane Congestion
Abstract
In accordance with some embodiments, when UPCON congestion is
detected, service data flows (SDFs) may be adjusted to account for
the problem and to avoid denial of service. In accordance with some
embodiments, a priority scheme may be implemented in which certain
users or certain types of data are given priority and in some cases
maximum bit rates (MBRs) may be imposed for either particular users
or certain types of data. Once the congestion alleviates, regular
service data flows may be again permitted.
Inventors: |
Shan; Chang Hong; (Shanghai,
CN) ; Siow; Eric; (Beaverton, OR) ;
Venkatachalam; Muthaiah; (Beaverton, OR) ; Jain;
Puneet K.; (Hillsboro, OR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Intel IP Corporation |
Santa Clara |
CA |
US |
|
|
Assignee: |
Intel IP Corporation
Santa Clara
CA
|
Family ID: |
51165025 |
Appl. No.: |
14/102894 |
Filed: |
December 11, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61752386 |
Jan 14, 2013 |
|
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Current U.S.
Class: |
370/229 |
Current CPC
Class: |
H04W 52/244 20130101;
H04W 72/0413 20130101; H04L 47/12 20130101; H04L 47/20 20130101;
H04L 5/0055 20130101; H04L 5/14 20130101; H04W 52/243 20130101;
H04W 28/0247 20130101; H04W 28/0252 20130101; H04W 24/02 20130101;
H04W 72/042 20130101; H04L 1/1861 20130101; H04W 72/0446 20130101;
H04W 52/283 20130101; H04W 24/10 20130101; H04W 28/08 20130101 |
Class at
Publication: |
370/229 |
International
Class: |
H04L 12/803 20060101
H04L012/803 |
Claims
1. A method comprising: in response to detection of radio access
network user plane congestion, changing a first priority of at
least one of a particular user or data type; using a service data
flow quality of service indicator to signal said priority change;
and in response to detection of the termination of said congestion,
changing priority back to the first priority.
2. The method of claim 1 including changing a maximum bit rate in
response to said congestion.
3. The method of claim 1 including providing a service data flow
quality of service based rule for handling congestion.
4. The method of claim 3 including providing said rule as part of
PDP context or EPS bearer context.
5. The method of claim 4 including specifying a maximum uncongested
and congested bit rate for a service data flow.
6. The method of claim 1 including using an attach procedure to
signal said priority change.
7. The method of claim 1 including using dedicated bearer
activation to signal the priority change.
8. The method of claim 1 including using dedicated bearer
modification to signal the priority change.
9. The method of claim 1 including using user equipment requested
packet data network connectivity to signal the priority change.
10. One or more non-transitory computer readable media storing
instructions to implement a sequence comprising: signaling radio
access network user plane congestion using a service data flow
quality of service indicator; reducing a bit rate in response to
said service class indicator; and applying a service data flow
quality of service based rule for handling congestion.
11. The medium of claim 10, said sequence including decreasing a
maximum bit rate in response to said congestion.
12. The medium of claim 10, said sequence including providing a
service data flow quality of service based rule for handling
congestion.
13. The medium of claim 12, said sequence including providing said
rule as part of PDP context or EPS bearer context.
14. The medium of claim 13, said sequence including specifying a
maximum uncongested and congested bit rate for a service data
flow.
15. The medium of claim 10, said sequence including using an attach
procedure to signal said priority change.
16. The medium of claim 10, said sequence including using dedicated
bearer activation to signal the priority change.
17. The medium of claim 10, said sequence including using dedicated
bearer modification to signal the priority change.
18. The medium of claim 10, said sequence including using user
equipment requested packet data network connectivity to signal the
priority change.
19. An apparatus comprising: a processor to receive an indication
of user plane congestion and, in response, locate a rule for
handling the congestion; and an interface to transmit an indicator
to initiate a bit rate change in response to said congestion.
20. The apparatus of claim 19, said interface to transmit an
indicator to change a maximum bit rate in response to said
congestion.
21. The apparatus of claim 20, said interface to transmit a service
class indicator to initiate a bit rate change.
22. The apparatus of claim 19, said interface to locate a service
data flow based rule for handling congestion.
23. The apparatus of claim 19, said interface to use an attach
procedure to signal said priority change.
24. The apparatus of claim 19, said interface to use dedicated
bearer activation to initiate the change.
25. The apparatus of claim 19, said interface to use dedicated
bearer modification.
26. The apparatus of claim 19, said interface to use user equipment
requested packet data network connectivity to initiate the
change.
27. The apparatus of claim 19 including using touch screen display,
keyboard, antenna, and an application processor.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This is a non-provisional application claiming priority from
provisional application Ser. No. 61/752,386, filed Jan. 14, 2013,
hereby expressly incorporated by reference herein.
BACKGROUND
[0002] This relates generally to cellular telephone networks.
[0003] Mobile operators are experiencing significant increases in
user data traffic. For some operators, user data traffic has more
than doubled annually for several years. Although the data capacity
of networks has increased significantly, the observed increase in
user traffic outpaces the growth in capacity. This results in
increased network congestion and in a degraded user service
experience.
[0004] Radio Access Network (RAN) user plane congestion (UPCON)
occurs when the demand for RAN resources to transfer user data
exceeds the capacity to deliver the user with the expected quality
of service. UPCON can be triggered by user plane congestion due to
the full use of the cell capacity and user plane congestion due to
3GPP RAN to Evolved Packet Core (EPC) interface capacity
limitations. See 3.sup.rd Generation Partnership Project (3GPP)
Long Term Evolution (LTE) SA2, Release 12.
[0005] In the user plane congestion scenario, UPCON occurs when the
traffic volume exceeds the capacity of the cell. This may happen
because the number of devices in a cell generating user plane
traffic total the cell capacity and then an additional or existing
user equipment attempts to generate additional user plane
traffic.
[0006] User plane congestion due to RAN to EPC interface capacity
occurs when the user plane data volume of all the devices being
served exceeds the actual capacity of the RAN to EPC interface.
This potentially impacts all the involved user equipment. This
congestion may lead to excessive data rate reduction or service
denial. Even though each cell may have the necessary capacity to
support the user equipment it is serving, the capacity of the
interface has an impact on each user equipment and may, in the
worse case, actually prevent equipment from being offered any
capacity at all.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Some embodiments are described with respect to the following
figures:
[0008] FIG. 1 is a high level architectural depiction of one
embodiment;
[0009] FIG. 2 is a flow diagram for one embodiment;
[0010] FIG. 3 is a flow diagram for another embodiment;
[0011] FIG. 4 is a flow diagram for still another embodiment;
[0012] FIG. 5 is a flow diagram for yet another embodiment;
[0013] FIG. 6 is a flow chart for one embodiment;
[0014] FIG. 7 is a system depiction for one embodiment; and
[0015] FIG. 8 is a front elevation for one embodiment.
DETAILED DESCRIPTION
[0016] In accordance with some embodiments, when UPCON congestion
is detected, service data flows (SDFs) may be adjusted to account
for the problem and to avoid denial of service. In accordance with
some embodiments, a priority scheme may be implemented in which
certain users or certain types of data are given priority and in
some cases maximum bit rates (MBRs) may be imposed for either
particular users or certain types of data. Once the congestion
alleviates, regular service data flows may be again permitted.
[0017] A service class indicator may be used for communicating the
change in priorities. A service class indicator (SCI) is defined in
3GPP TS 29.281 [120] and enables the Gateway General Packet Radio
Service (GPRS) Support Node (GGSN)/Packet Data Network Gateway
(P-GW) to provide the A/Gb mode GSM EDGE Radio Access Network
(GERAN) access with an indication in the downlink user plane packet
to assist the A/Gb mode GERAN access in providing specific radio
resource management (RRM) treatment to improve radio resource
control and the overall performance of the GERAN. While generally
the SCI is only used in GERAN networks, comparable embodiments can
be implemented in other networks.
[0018] In some embodiments, an SCI can be used to prioritize
service classes. It may be added to a header and a packet may be
prioritized based on the SCI and the header. This packet may be
transferred further downstream on the GERAN side based on that
priority. Thus in some embodiments radio resource prioritization
can be based on the SCI.
[0019] When an UPCON is detected, some flows may be given higher
priority. While this may adversely affect other flows, it may be
necessary to prevent denial of service. In addition, some users may
be given higher priority and some data types may be given higher or
lower priority. For example when an UPCON is identified, the
priority of video data may be reduced to free up bandwidth.
[0020] In one embodiment, the bit 8 of the service class indicator
allows the system to set or not set the priorities. For example
when the bit 8 is equal to 1, a standardized service class
indicator may be utilized without changing prioritization. But when
the bit 8 is set equal to zero, then the bits 1 to 7 are used to
set the priorities for various users or data types of a service
data flow.
[0021] Thus, rules may be recorded which become activated when a
given UPCON is detected. The service class indicator can act as the
identity of the SDF level quality of service (QoS) rule or may be
mapped to the identity of the SDF level quality of service rules.
Thus, the identity of the SDF level quality of service rule may be
named as an SQI or SDF quality of service identity. The SQI can be
an SCI or mapped to SCI.
[0022] The SQI may be part of the packet data protocol (PDP)
context or Evolved Packet System (EPS) Bearer Context allocated by
the P-GW/GGSN and may be transferred from the P-GW/GGSN to the
Serving gateway (S-GW), Service GPRS support node (SGSN), and
E-UTRAN Node B (eNB) in sequence during Policy and Charging Control
(PCC) rule provision procedures.
[0023] For each service data flow, the following information
elements of the SDF context may be included: SQI, traffic flow
template (TFT), Uncongested SDF QoS, SDF maximum bit rate,
congested SDF QoS or SDF maximum bit rate (SMBR). The SDF maximum
bit rate means the maximum bit rate for the service data flow. If
the value of the SMBR of the congested SDF QoS is set to zero, this
means the designated SDFs will be cut off when the RAN UPCON event
is detected. The SDF context may be part of the EPS Bearer Context
or the PDP context.
[0024] FIG. 1 shows an architectural reference model for the
non-roaming architecture for 3GPP accesses. Other architectures may
also be used including a single gateway configuration option and a
roaming architecture with roam routed traffic.
[0025] In the non-roaming architecture 10, the user equipment 12
may be coupled over an LTE connection to an Evolved Universal
Terrestrial Radio Access Network (E-UTRAN) 14. The E-UTRAN is
coupled to a serving gateway 16 in turn coupled to a packet data
network (PDN) gateway 15. The PDN gateway 15 is coupled to the
operator's Internet protocol services 20.
[0026] The PDN gateway 15 and operator's Internet protocol services
20 are connected to the Policy Charging and Rules Function (PCRF)
22. The gateway 15 may include processor 34 and interface 36,
coupled to processor 34, to transmit an indicator to initiate a bit
rate charge to the serving gateway 16. The serving gateway 16 is
coupled to a UTRAN 30 and SGSN 28 is coupled to a GERAN 32 and a
Mobility Management Entity (MME) 24. The MME 24 is, in turn,
coupled to home subscriber server (HSS) 26. See 3GPP TS 23.401
VII.60 (2013-06).
[0027] The SDF context is transferred to the E-UTRAN using the
following procedure. Specifically as shown in FIG. 2, a
conventional attach procedure as defined in clause 5.3.2.1 of TS
23.401 may be used wherein the context is transferred in steps
15-17 via access point name (APN)--Aggregate Maximum Bit Rate
(AMBR). The AMBR is a subscription parameter stored per APN in the
HSS. It limits the aggregate bit rate that can be expected to be
provided across all non-guaranteed bit rate (GBR) bearer and across
all PDN connections of the same APN. Each non-GBR bearer could
potentially use the whole APN-AMBR (e.g. when no other non-GBR
bearers carry traffic). The P-GW enforces the APN-AMBR in the
downlink. The UE and P-GW enforce the APN-AMBR on the uplink.
[0028] A UE/user needs to register with the network to receive
services that require registration. This registration is described
as Network Attachment. The always-on Internet Protocol (IP)
connectivity for UE/users of the EPS is enabled by establishing a
default EPS bearer during Network Attachment. The PCC rules applied
to the default EPS bearer may be predefined in the PDN GW and
activated in the attachment by the PDN GW itself. The attach
procedure may trigger one or multiple Dedicated Bearer
Establishment procedures to establish dedicated EPS bearer(s) for
that UE. During the attach procedure, the UE may request for an IP
address allocation.
[0029] During the initial attach procedure the Mobile Equipment
(ME) Identity is obtained from the UE. The MME operator may check
the ME Identity with an Equipment Identity Register (EIR). The MME
passes the International ME Identity (IMEISV) to the HSS and to the
PDN GW.
[0030] During the initial attach procedure, if the MME supports
single radio voice call continuity (SRVCC) and if any of the
conditions described in step 8 in FIG. 2 are satisfied, the MME
informs the HSS with the UE SRVCC capability.
[0031] In order to limit load on the network, only when performing
an E-UTRAN attach with a new Public Land Mobile Network (PLMN)
(i.e. not the registered PLMN or an equivalent PLMN of the
registered PLMN), a UE configured to perform attach with
International Mobile Subscriber Identity (IMSI) at PLMN change (see
3GPP TS 24.368 [69]) may identify itself by its IMSI instead of any
stored temporary identifier.
[0032] This procedure may also be used to establish the first PDN
connection over E-UTRAN when the UE already has active PDN
connections over a non-3GPP access network and wants to establish
simultaneous PDN connections to different APNs over multiple
accesses.
[0033] In the following, the numbers along the left column
correspond to step numbers in FIG. 2: [0034] 1. The UE initiates
the Attach procedure by the transmission, to the eNodeB, of an
attach request. [0035] If the UE has valid security parameters, the
attach request message may be integrity protected by the Non-Access
Stratum-medium access control (NAS-MAC) in order to allow
validation of the UE by the MME. A Security Key Identifier
(KSIASME), Non-access Stratum (NAS) sequence number and NAS-Medium
Access Control (MAC) are included if the UE has valid EPS security
parameters. NAS sequence number indicates the sequential number of
the NAS message. If the UE does not have a valid EPS security
association, then the attach request message is not integrity
protected. In this case the security association is established in
step 5a. The UE network capabilities indicate also the supported
NAS and security algorithms. PDN type indicates the requested IP
version (IPv4, IPv4/IPv6, IPv6). Protocol Configuration Options
(PCO) may be used to transfer parameters between the UE and the PDN
GW, and may be sent transparently through the MME and the Serving
GW. The Protocol Configuration Options may include the Address
Allocation Preference indicating that the UE prefers to obtain an
IPv4 address only after the default bearer activation by means of
Dynamic Host Configuration Protocol (DHCP)v4. A "bearer" is a basic
traffic separation element that enables differential treatment of
traffic with differential QoS requirements. It is in accordance
with clause 5.4.1 of TS 23.401. If the UE intends to send PCO which
require ciphering or send an APN, or both, the UE shall set the
Ciphered Options Transfer Flag and send PCO or Access Point Name
(APN) or both only after authentication and NAS security setup have
been completed. If the UE has UTRAN or GERAN capabilities, it may
send the network request support UE (NRSU) in the PCO to indicate
the support of the network requested bearer control in UTRAN/GERAN.
The UE sends the extended TFT Support UE (ETFTU) in the PCO to
indicate the support of the extended TFT filter format. Request
Type may be included in the ESM message container and indicates
"Handover" (HA) when the UE has already an activated PDN GW/HA due
to mobility with non-3GPP accesses. Attach Type indicates whether
it is an EPS attach or a combined EPS/IMSI attach or an Emergency
Attach. [0036] 2. The eNodeB derives the MME from the RRC
parameters carrying the old Globally Unique MME Identifier (GUMMEI)
and the indicated Selected Network. If that MME is not associated
with the eNodeB or the old GUMMEI is not available, the eNodeB
selects an MME as described in clause 4.3.8.3 of TS 23.401 on "MME
selection function". The eNodeB forwards the Attach Request message
to the new MME contained in a 51-MME control message (Initial UE
message) together with the Selected Network Closed Subscriber Group
(CSG) access mode, CSG ID, Local Gateway (L-GW) address, and
Tracking Area Identity (TAI) plus E-UTRAN Cell Mobile Identifier
(ECGI) of the cell from where it received the message to the new
MME. CSG ID is provided if the UE attaches via a CSG cell or hybrid
cell. CSG access mode is provided if the UE attaches via a hybrid
cell. If the CSG access mode is not provided but the CSG ID is
provided, the MME shall consider the cell as a CSG cell. If the
eNodeB has a collocated L-GW, it includes the L-GW address in the
Initial UE message to the MME. [0037] 3. If the UE identifies
itself with Globally Unique Temporary Identity (GUTI) and the MME
has changed since detach, the new MME determines the type of the
old node, i.e. MME or SGSN, as specified in clause 4.3.19, uses the
GUTI received from the UE to derive the old MME/SGSN address, and
sends an Identification Request (old GUTI, complete Attach Request
message) to the old MME/SGSN to request the IMSI. If the request is
sent to an old MME, the old MME first verifies the Attach Request
message by NAS MAC and then responds with Identification Response
(IMSI, MM Context). If the request is sent to an old SGSN, the old
SGSN first verifies the Attach Request message by the P-TMSI
signature and then responds with Identification Response (MM
Context). If the UE is not known in the old MME/SGSN or if the
integrity check or P-TMSI signature check for the Attach Request
message fails, the old MME/SGSN responds with an appropriate error
cause. [0038] The additional GUTI in the Attach Request message
allows the new MME to find any already existing UE context stored
in the new MME when the old GUTI indicates a GUTI mapped from a
packet TMSI (P-TMSI) and routing area identity (RAI). [0039] 4. If
the UE is unknown in both the old MME/SGSN and new MME, the new MME
sends an Identity Request to the UE to request the IMSI. The UE
responds with Identity Response (IMSI). [0040] 5a. If no UE context
for the UE exists anywhere in the network, if the Attach Request
(sent in step 1) was not integrity protected, or if the check of
the integrity failed, then authentication and NAS security setup to
activate integrity protection and NAS ciphering may be mandatory in
one embodiment. Otherwise it is optional. If NAS security algorithm
is to be changed, the NAS security setup is performed in this step.
The authentication and NAS security setup functions are defined in
clause 5.3.10 on "Security Function". [0041] After step 5a, all NAS
messages shall be protected by the NAS security functions
(integrity and ciphering) indicated by the MME unless the UE is
emergency attached and not successfully authenticated. [0042] 5b.
The International ME Identity (IMEISV) shall be retrieved from the
UE. The ME identity shall be transferred encrypted unless the UE
performs Emergency Attach and cannot be authenticated. [0043] In
order to minimise signalling delays, the retrieval of the ME
Identity may be combined with NAS security setup in step 5a. The
MME may send the ME Identity Check Request (ME Identity, IMSI) to
the EIR. The EIR shall respond with ME Identity Check Ack (Result).
Dependent upon the Result, the MME decides whether to continue with
this Attach procedure or to reject the UE. For an Emergency Attach,
the IMEI check to the EIR may be performed. If the IMEI is blocked,
operator policies determine whether the Emergency Attach procedure
continues or is stopped. [0044] 6. If the UE has set the Ciphered
Options Transfer Flag in the Attach Request message, the Ciphered
Options i.e. PCO or APN or both, shall now be retrieved from the
UE. [0045] In order to handle situations where the UE may have
subscriptions to multiple PDNs, if the Protocol Configuration
Options contains user credentials, then the UE should also send the
APN to the MME. [0046] 7. If there are active bearer contexts in
the new MME for this particular UE (i.e. the UE re-attaches to the
same MME without having properly detached before), the new MME
deletes these bearer contexts by sending Delete Session Request
(LBI) messages to the gateways involved. The gateways acknowledge
with Delete Session Response (Cause) message. If a PCRF is
deployed, the PDN GW employs an IP-CAN Session Termination
procedure to indicate that resources have been released. [0047] 8.
If the MME has changed since the last detach, or if there is no
valid subscription context for the UE in the MME, or if the UE
provides an IMSI or the UE provides an old GUTI which doesn't refer
to a valid context in the MME, or for some network sharing scenario
if the PLMN-ID of the TAI supplied by the eNodeB is different from
that of the GUTI in the UE's context, the MME sends an Update
Location Request (MME Identity, IMSI, ME Identity (IMEISV), MME
Capabilities, Update Location Request-Flags (ULR-Flags),
Homogeneous Support of IMS Voice over PS Sessions, UE SRVCC
capability, equivalent PLMN list) message to the HSS. The MME
capabilities indicate the MME's support for regional access
restrictions functionality. ULR-Flags indicates
"Initial-Attach-Indicator" as this is an Attach procedure. The
inclusion of the equivalent PLMN list indicates that the MME
supports the inter-PLMN handover to a CSG cell in an equivalent
PLMN using the subscription information of the target PLMN. The
"Homogenous Support of IMS Voice over PS Sessions" indication (see
clause 4.3.5.8A) may not be included unless the MME has completed
its evaluation of the support of "IMS Voice over PS Session" as
specified in clause 4.3.5.8. [0048] 9. The HSS sends Cancel
Location (IMSI, Cancellation Type) to the old MME. The old MME
acknowledges with Cancel Location Ack (IMSI) and removes the MM and
bearer contexts. If the ULR-Flags indicates
"Initial-Attach-Indicator" and the HSS has the SGSN registration,
then the HSS sends Cancel Location (IMSI, Cancellation Type) to the
old SGSN. The Cancellation Type indicates the old MME/SGSN to
release the old Serving gateway resource. [0049] 10. If there are
active bearer contexts in the old MME/SGSN for this particular UE,
the old MME/SGSN deletes these bearer contexts by sending Delete
Session Request (LBI) messages to the gateways involved. The
gateways return Delete Session Response (Cause) message to the old
MME/SGSN. If a PCRF is deployed, the PDN GW employs an
IP-Connectivity Access Network (IP-CAN) Session Termination
procedure as defined in TS 23.203[6] to indicate that resources
have been released. [0050] 11. The HSS acknowledges the Update
Location message by sending an Update Location Ack (IMSI,
Subscription data) message to the new MME. The Subscription Data
contain one or more PDN subscription contexts. Each PDN
subscription context contains an `EPS subscribed QoS profile` and
the subscribed APN aggregate maximum bit rate (AMBR) (see clause
4.7.3). The new MME validates the UE's presence in the (new) TA. If
due to regional subscription restrictions or access restrictions
(e.g. CSG restrictions) the UE is not allowed to attach in the TA
or due to subscription checking fails for other reasons, the new
MME rejects the Attach Request with an appropriate cause. If all
checks are successful then the new MME constructs a context for the
UE. If the APN provided by the UE is not allowed by subscription,
or the Update Location is rejected by the HSS, the new MME rejects
the Attach Request from the UE with an appropriate cause. [0051]
12. For an Emergency Attach the MME applies the parameters from MME
Emergency Configuration Data for the emergency bearer establishment
performed in this step and any potentially stored IMSI related
subscription data are ignored by the MME. [0052] If the UE performs
Initial or Handover Attach via a CSG cell and there is no
subscription for that CSG or the CSG subscription is expired the
MME shall reject the Attach Request with an appropriate cause. If
the UE has this CSG ID and associated PLMN on its Allowed CSG list
the UE shall remove the CSG ID and associated PLMN from the list
when receiving this reject cause. [0053] If a subscribed PDN
address is allocated for the UE for this APN, the PDN subscription
context contains the UE's IPv4 address and/or the IPv6 prefix and
optionally the PDN GW identity. If the PDN subscription context
contains a subscribed IPv4 address and/or IPv6 prefix, the MME
indicates it in the PDN address. For Request Type indicating
"Initial request", if the UE does not provide an APN, the MME shall
use the PDN GW corresponding to the default APN for default bearer
activation. If the UE provides an APN, this APN shall be employed
for default bearer activation. For Request Type indicating
"Handover", if the UE provides an APN, the MME shall use the PDN GW
corresponding to the provided APN for default bearer activation, If
the UE does not provide an APN, and the subscription context from
HSS contains a PDN GW identity corresponding to the default APN,
the MME shall use the PDN GW corresponding to the default APN for
default bearer activation. The case where the Request Type
indicates "Handover" and the UE does not provide an APN, and the
subscription context from HSS does not contain a PDN GW identity
corresponding to the default APN constitutes an error case. If the
Request Type indicates "Initial request" and the selected PDN
subscription context contains no PDN GW identity the new MME
selects a PDN GW as described in clause 4.3.8.1 on PDN GW selection
function (3GPP accesses). If the PDN subscription context contains
a dynamically allocated PDN GW identity and the Request Type does
not indicate "Handover" the MME may select a new PDN GW as
described in clause PDN GW selection function, e.g. to allocate a
PDN GW that allows for more efficient routing. [0054] The new MME
selects a Serving GW as described in clause 4.3.8.2 on Serving GW
selection function and allocates an EPS Bearer Identity for the
Default Bearer associated with the UE. Then it sends a Create
Session Request (IMSI, MSISDN, MME TEID for control plane, PDN GW
address, PDN Address, APN, RAT type, Default EPS Bearer QoS, PDN
Type, APN-AMBR, EPS Bearer Identity, Protocol Configuration
Options, Handover Indication, ME Identity (IMEISV), User Location
Information (ECGI), UE Time Zone, User CSG Information, MS Info
Change Reporting support indication, Selection Mode, Charging
Characteristics, Trace Reference, Trace Type, Trigger Id, OMC
Identity, Maximum APN Restriction, Dual Address Bearer Flag, the
Protocol Type over S5/S8, Serving Network) message to the selected
Serving GW. User CSG Information includes CSG ID, access mode and
CSG membership indication. [0055] The RAT type is provided in this
message for the later PCC decision. The subscribed APN-AMBR for the
APN is also provided in this message. The MSISDN is included if
provided in the subscription data from the HSS. Handover Indication
is included if the Request Type indicates handover. Selection Mode
indicates whether a subscribed APN was selected, or a
non-subscribed APN sent by the UE was selected. Charging
Characteristics indicates which kind of charging the bearer context
is liable for. The MME may change the requested PDN type according
to the subscription data for this APN as described in clause
5.3.1.1. The MME shall set the Dual Address Bearer Flag when the
PDN type is set to IPv4v6 and all SGSNs which the UE may be handed
over to are Release 8 or above supporting dual addressing, which is
determined based on node pre-configuration by the operator. The
Protocol Type over S5/S8 is provided to Serving GW which protocol
should be used over S5/S8 interface. [0056] The Maximum APN
Restriction denotes the most stringent restriction as required by
any already active bearer context. If there are no already active
bearer contexts, this value is set to the least restrictive type
(see clause 15.4 of TS 23.060 [7]). If the P-GW receives the
Maximum APN Restriction, then the P-GW shall check if the Maximum
APN Restriction value does not conflict with the APN Restriction
value associated with this bearer context request. If there is no
conflict the request shall be allowed, otherwise the request shall
be rejected with sending an appropriate error cause to the UE.
[0057] If the MME requires the eNB to check whether the UE radio
capabilities are compatible with the network configuration (e.g.
whether the SRVCC or frequency support by the UE matches that of
the network) to be able to set the IMS voice over PS Session
Supported Indication (see clause 4.3.5.8), then the MME may send a
UE Radio Capability Match Request to the eNB as defined in clause
5.3.14. [0058] 13. The Serving GW creates a new entry in its EPS
Bearer table and sends a Create Session Request (IMSI, MSISDN, APN,
Serving GW Address for the user plane, Serving GW Tunnel Endpoint
Identifier (TEID) of the user plane, Serving GW TEID of the control
plane, RAT type, Default EPS Bearer QoS, PDN Type, PDN Address,
subscribed APN-AMBR, EPS Bearer Identity, Protocol Configuration
Options, Handover Indication, ME Identity, User Location
Information (ECGI), UE Time Zone, User CSG Information, MS Info
Change Reporting support indication, Selection Mode, Charging
Characteristics, Trace Reference, Trace Type, Trigger Id, Operation
and Maintenance Centre (OMC) Identity, Maximum APN Restriction,
Dual Address Bearer Flag, Serving Network) message to the PDN GW
indicated by the PDN GW address received in the previous step.
After this step, the Serving GW buffers any downlink packets it may
receive from the PDN GW without sending a Downlink Data
Notification message to the MME until it receives the Modify Bearer
Request message in step 23 below. The Mobile Subscriber Integrated
Services Digital Network Number (MSISDN) is included if received
from the MME. [0059] 14. If dynamic PCC is deployed and the
Handover Indication is not present, the PDN GW performs an IP-CAN
Session Establishment procedure as defined in TS 23.203 [6], and
thereby obtains the default PCC rules for the UE. This may lead to
the establishment of a number of dedicated bearers following the
procedures defined in clause 5.4.1 in association with the
establishment of the default bearer. [0060] The IMSI, APN, UE IP
address, User Location Information (ECGI), UE Time Zone, Serving
Network, RAT type, APN-AMBR, Default EPS Bearer QoS, ETFTU (if
ETFTU is not provided it means UE and/or the PDN GW does not
support the extended TFT filter format) are provided to the PCRF by
the PDN GW if received by the previous message. The User Location
Information and UE Time Zone are used for location based charging.
For emergency attached UEs which are unauthenticated the PDN GW
provides the IMEI as the UE Identity instead of IMSI, to the PCRF.
If the PCRF decides that the PDN connection may use the extended
TFT filter format, it may return the ETFTN indicator to the PDN GW
for inclusion in the protocol Configuration Options returned to the
UE. [0061] The PCRF may modify the APN-AMBR and the QoS parameters
(QCI and ARP) associated with the default bearer in the response to
the PDN GW as defined in TS 23.203 [6]. [0062] If dynamic PCC is
deployed and the Handover Indication is present, the PDN GW
executes a Policy and Charging Enforcement Function (PCEF)
Initiated IP-CAN Session Modification procedure with the PCRF as
specified in TS 23.203 [6] to report the new IP-CAN type. Depending
on the active PCC rules, the establishment of dedicated bearers for
the UE may be required. The establishment of those bearers shall
take place in combination with the default bearer activation. This
procedure can continue without waiting for a PCRF response. If
changes to the active PCC rules are required, the PCRF may provide
them after the handover procedure is finished. [0063] In both cases
(Handover Indication is present or not), if dynamic PCC is not
deployed, the PDN GW may apply local QoS policy. This may lead to
the establishment of a number of dedicated bearers for the UE
following the procedures defined in clause 5.4.1 in combination
with the establishment of the default bearer. [0064] If the CSG
information reporting triggers are received from the PCRF, the PDN
GW should set the CSG Information Reporting Action IE accordingly.
[0065] 15. The P-GW creates a new entry in its EPS bearer context
table and generates a Charging Id for the Default Bearer. The new
entry allows the P-GW to route user plane PDUs between the S-GW and
the packet data network, and to start charging. The way the P-GW
handles charging characteristics that it may have received is
defined in TS 32.251 [44]. [0066] The PDN GW returns a Create
Session Response (PDN GW Address for the user plane, PDN GW TEID of
the user plane, PDN GW TEID of the control plane, PDN Type, PDN
Address, EPS Bearer Identity, EPS Bearer QoS, Protocol
Configuration Options, Charging Id, Prohibit Payload Compression,
APN Restriction, Cause, MS Info Change Reporting Action (Start) (if
the PDN GW decides to receive UE's location information during the
session), CSG Information Reporting Action (Start) (if the PDN GW
decides to receive UE's User CSG information during the session),
APN-aggregate maximum bit rate (AMBR) message to the Serving GW.
The aggregate maximum bit rate (AMBR) is adjusted based on
congestion. The PDN GW takes into account the received PDN type,
the Dual Address Bearer Flag and the policies of operator when the
PDN GW selects the PDN type to be used as follows. If the received
PDN type is IPv4v6 and both IPv4 and IPv6 addressing is possible in
the PDN but the Dual Address Bearer Flag is not set, or only single
IP version addressing for this APN is possible in the PDN, the PDN
GW selects a single IP version (either IPv4 or IPv6). If the
received PDN type is IPv4 or IPv6, the PDN GW uses the received PDN
type if it is supported in the PDN, otherwise an appropriate error
cause will be returned. The PDN GW allocates a PDN Address
according to the selected PDN type. If the PDN GW has selected a
PDN type different from the received PDN Type, the PDN GW indicates
together with the PDN type IE a reason cause to the UE why the PDN
type has been modified, as described in clause 5.3.1.1. PDN Address
may contain an IPv4 address for IPv4 and/or an IPv6 prefix and an
Interface Identifier. If the PDN has been configured by the
operator so that the PDN addresses for the requested APN may be
allocated by usage of DHCPv4 only, or if the PDN GW allows the UE
to use DHCPv4 for address allocation according to the Address
Allocation Preference received from the UE, the PDN Address may be
set to 0.0.0.0, indicating that the IPv4 PDN address shall be
negotiated by the UE with DHCPv4 after completion of the Default
Bearer Activation procedure. For external PDN addressing for IPv6,
the PDN GW obtains the IPv6 prefix from the external PDN using
either RADIUS or Diameter client function. In the PDN Address field
of the Create Session Response, the PDN GW includes the Interface
Identifier and IPv6 prefix. The PDN GW sends Router Advertisement
to the UE after default bearer establishment with the IPv6 prefix
information for all cases. [0067] If the PDN address is contained
in the Create Session Request, the PDN GW shall allocate the IPv4
address and/or IPv6 prefix contained in the PDN address to the UE.
The IP address allocation details are described in clause 5.3.1 on
"IP Address Allocation". The PDN GW derives the Bearer Control Mode
(BCM) based on the NRSU and operator policy. The PDN GW derives
whether the extended TFT filter format is to be used based on the
ETFTU, ETFTN received from the PCRF and operator policy. Protocol
Configuration Options contains the BCM, ETFTN as well as optional
PDN parameters that the P-GW may transfer to the UE. These optional
PDN parameters may be requested by the UE, or may be sent
unsolicited by the P-GW. Protocol Configuration Options are sent
transparently through the MME. [0068] 16. The Serving GW returns a
Create Session Response (PDN Type, PDN Address, Serving GW address
for User Plane, Serving GW TEID for 51-U User Plane, Serving GW
TEID for control plane, EPS Bearer Identity, EPS Bearer QoS, PDN GW
addresses and TEIDs (GTP-based S5/S8) or GRE keys (PMIP-based
S5/S8) at the PDN GW(s) for uplink traffic, Protocol Configuration
Options, Prohibit Payload Compression, APN Restriction, Cause, MS
Info Change Reporting Action (Start), CSG Information Reporting
Action (Start), APN-AMBR) message to the new MME. [0069] 17. If an
APN Restriction is received, then the MME may store this value for
the Bearer Context and the MME shall check this received value with
the stored value for the Maximum APN Restriction to ensure there
are no conflicts between values. If the Bearer Context is accepted,
the MME may determine a (new) value for the Maximum APN
Restriction. If there is no previously stored value for Maximum APN
Restriction, then the Maximum APN Restriction may be set to the
value of the received APN Restriction. [0070] If the MS Info Change
Reporting Action (Start) and/or the CSG Information Reporting
Action (Start) are received for this bearer context, then the MME
shall store this for the bearer context and the MME shall report to
that P-GW via the S-GW whenever a UE's location and/or User CSG
information change occurs that meets the P-GW request, as described
in clause 15.1.1a of TS 23.060 [7]. [0071] The MME determines the
UE AMBR to be used by the eNodeB based on the subscribed UE-AMBR
and the APN-AMBR for the default APN, see clause 4.7.3. [0072] The
new MME sends an Attach Accept (APN, GUTI, PDN Type, PDN Address,
TAI List, EPS Bearer Identity, Session Management Request, Protocol
Configuration Options, NAS sequence number, NAS-MAC, IMS Voice over
PS session supported Indication, Emergency Service Support
indicator, LCS Support Indication) message to the eNodeB. GUTI is
included if the new MME allocates a new GUTI. This message is
contained in an S1_MME control message Initial Context Setup
Request. This S1 control message also includes the AS security
context information for the UE, the Handover Restriction List, the
EPS Bearer QoS, the UE-AMBR, EPS Bearer Identity, as well as the
TEID at the Serving GW used for user plane and the address of the
Serving GW for user plane. In addition, if the PDN connection is
established for Local IP Access, the 51 control message includes a
Correlation ID for enabling the direct user plane path between the
HeNB and the L-GW. [0073] In the Attach Accept message, the MME
does not include the IPv6 prefix within the PDN Address. The MME
includes the EPS Bearer QoS parameter QCI and APN-AMBR into the
Session Management Request. Furthermore, if the UE has UTRAN or
GERAN capabilities and the network supports mobility to UTRAN or
GERAN, the MME uses the EPS bearer QoS information to derive the
corresponding PDP context parameters QoS Negotiated (R99 QoS
profile), Radio Priority, Packet Flow Id and TI and includes them
in the Session Management Request. If the UE indicated in the UE
Network Capability it does not support BSS packet flow procedures,
then the MME shall not include the Packet Flow Id. Handover
Restriction List is described in clause 4.3.5.7 "Mobility
Restrictions". The MME sets the IMS Voice over PS session supported
Indication as described in clause 4.3.5.8. LCS Support Indication
indicates whether the network supports the EPC-MO-LR and/or
CS-MO-LR as described in TS 23.271 [57]. [0074] If the UE initiates
the Attach procedure at a hybrid cell, the MME shall check whether
the CSG ID is contained in the CSG subscription and is not expired.
The MME shall send an indication whether the UE is a CSG member to
the RAN along with the 51-MME control message. Based on this
information the RAN may perform differentiated treatment for CSG
and non-CSG members. [0075] If the MME or PDN GW has changed the
PDN Type, an appropriate reason cause shall be returned to the UE
as described in clause 5.3.1.1. [0076] 18. The eNodeB sends the RRC
Connection Reconfiguration message including the EPS Radio Bearer
Identity to the UE, and the Attach Accept message will be sent
along to the UE. The UE shall store the QoS Negotiated, Radio
Priority, Packet Flow Id and TI, which it received in the Session
Management Request, for use when accessing via GERAN or UTRAN. The
APN is provided to the UE to notify it of the APN for which the
activated default bearer is associated. For further details, see TS
36.331[37]. The UE may provide EPS Bearer QoS parameters to the
application handling the traffic flow(s). The application usage of
the EPS Bearer QoS is implementation dependent. The UE shall not
reject the RRC Connection Reconfiguration on the basis of the EPS
Bearer QoS parameters contained in the Session Management Request.
[0077] If the attach procedure is initiated by manual CSG selection
and occurs via a CSG cell, the UE upon receiving the Attach accept
shall check if the CSG ID and associated PLMN of the cell where the
UE has sent the Attach Request message is contained in its Allowed
CSG list. If the CSG ID and associated PLMN is not in the UE's
Allowed CSG list, the UE shall add the CSG ID and associated PLMN
to its Allowed CSG list. Manual CSG selection is not supported when
an emergency service has been initiated. [0078] 19. The UE sends
the RRC Connection Reconfiguration Complete message to the eNodeB.
For further details, see TS 36.331 [37]. [0079] 20. The eNodeB
sends the Initial Context Response message to the new MME. This
Initial Context Response message includes the TEID of the eNodeB
and the address of the eNodeB used for downlink traffic on the S1_U
reference point. [0080] The MME shall be prepared to receive this
message either before or after the Attach Complete message (sent in
step 22). [0081] If the Correlation ID was included in the Initial
Context Setup Request message, the eNodeB shall use the included
information to establish direct user plane path with the L-GW and
forward uplink data for Local IP Access accordingly. [0082] 21. The
UE sends a Direct Transfer message to the eNodeB, which includes
the Attach Complete (EPS Bearer Identity, NAS sequence number,
NAS-MAC) message. [0083] 22. The eNodeB forwards the Attach
Complete message to the new MME in an Uplink NAS Transport message.
[0084] After the Attach Accept message and once the UE has obtained
a PDN Address, the UE can then send uplink packets towards the
eNodeB which will then be tunneled to the Serving GW and PDN GW. If
the UE requested for a dual address PDN type (IPv4v6) to a given
APN and was granted a single address PDN type (IPv4 or IPv6) by the
network with a reason cause indicating that only single IP version
per PDN connection is allowed sent together with the PDN type, the
UE should request for the activation of a parallel PDN connection
to the same APN with a single address PDN type (IPv4 or IPv6) other
than the one already activated. If the UE receives no reason cause
in step 18 in response to an IPv4v6 PDN type and it receives an
IPv6 Interface Identifier apart from the IPv4 address or 0.0.0.0 in
the PDN Address field, it considers that the request for a dual
address PDN was successful. It can wait for the Router
Advertisement from the network with the IPv6 prefix information or
it may send Router Solicitation if necessary.
[0085] 23. Upon reception of both, the Initial Context Response
message in step 20 and the Attach Complete message in step 22, the
new MME sends a Modify Bearer Request (EPS Bearer Identity, eNodeB
address, eNodeB TEID, Handover Indication) message to the Serving
GW. [0086] 23a. If the Handover Indication is included in step 23,
the Serving GW sends a Modify Bearer Request (Handover Indication)
message to the PDN GW to prompt the PDN GW to tunnel packets from
non 3GPP IP access to 3GPP access system and immediately start
routing packets to the Serving GW for the default and any dedicated
EPS bearers established. [0087] 23b. The PDN GW acknowledges by
sending Modify Bearer Response to the Serving GW. [0088] 24. The
Serving GW acknowledges by sending Modify Bearer Response (EPS
Bearer Identity) message to the new MME. The Serving GW can then
send its buffered downlink packets. [0089] 25. After the MME
receives Modify Bearer Response (EPS Bearer Identity) message, if
Request Type does not indicate handover and an EPS bearer was
established and the subscription data indicates that the user is
allowed to perform handover to non-3GPP accesses, and if the MME
selected a PDN GW that is different from the PDN GW identity which
was indicated by the HSS in the PDN subscription context, the MME
shall send a Notify Request including the APN and PDN GW identity
to the HSS for mobility with non-3GPP accesses. The message shall
include information that identifies the PLMN in which the PDN GW is
located. [0090] If the ME identity of the UE has changed and step 8
has not been performed, the MME sends a Notify Request (ME
Identity) message to inform the HSS of the updated ME identity.
[0091] 26. The HSS stores the APN and PDN GW identity pair and
sends a Notify Response to the MME.
[0092] FIG. 2 is a user plane congestion due to 3GPP RAN to EPC
interface capacity limitation.
[0093] As another alternative, the Steps 15-17 may be replaced by
the dedicated bearer activation sequence shown in FIG. 3. The SDF
contexts are delivered to the eNB via Steps 1, 2, 3 and 4. SDF
represent the IP packets related to a user service, like web
browsing or email. SDF are bound to specific bearers based on
policies defined in the network operator.
[0094] The numbers along the left column correspond to the step
numbers in FIG. 3: [0095] 1. If dynamic PCC is deployed, the PCRF
sends a PCC decision provision (QoS policy) message to the PDN GW.
This corresponds to the initial steps of the PCRF-Initiated IP-CAN
Session Modification procedure or to the PCRF response in the PCEF
initiated IP-CAN Session Modification procedure as defined in TS
23.203 [6], up to the point that the PDN GW requests IP-CAN Bearer
Signalling. The PCC decision provision message may indicate that
User Location Information and/or UE Time Zone Information is to be
provided to the PCRF as defined in TS 23.203[6]. If dynamic PCC is
not deployed, the PDN GW may apply local QoS policy. [0096] 2. The
PDN GW uses this QoS policy to assign the EPS Bearer QoS, i.e., it
assigns the values to the bearer level QoS parameters QCI, ARP, GBR
and MBR; see clause 4.7.3. The PGW generates a Charging Id for the
dedicated bearer. The PDN GW sends a Create Bearer Request message
(IMSI, Precoding Type Indicator (PTI), EPS Bearer QoS, TFT, S5/S8
TEID, Charging Id, LBI, Protocol Configuration Options) to the
Serving GW, the Linked EPS Bearer Identity (LBI) is the EPS Bearer
Identity of the default bearer. The Procedure Transaction Id (PTI)
parameter is only used when the procedure was initiated by a UE
Requested Bearer Resource Modification Procedure--see clause 5.4.5.
Protocol Configuration Options may be used to transfer application
level parameters between the UE and the PDN GW (see TS 23.228[52]),
and are sent transparently through the MME and the Serving GW.
[0097] 3. The Serving GW sends the Create Bearer Request (IMSI,
PTI, EPS Bearer QoS, TFT, S1-TEID, PDN GW TEID (GTP-based S5/S8),
LBI, Protocol Configuration Options) message to the MME. If the UE
is in ECM-IDLE state the MME will trigger the Network Triggered
Service Request from step 3 (which is specified in clause 5.3.4.3).
In that case the following steps 4-7 may be combined into Network
Triggered Service Request procedure or be performed standalone.
[0098] 4. The MME selects an EPS Bearer Identity, which has not yet
been assigned to the UE. The MME then builds a Session Management
Request including the PTI, TFT, EPS Bearer QoS parameters, Protocol
Configuration Options, the EPS Bearer Identity and the Linked EPS
Bearer Identity (LBI). If the UE has UTRAN or GERAN capabilities
and the network supports mobility to UTRAN or GERAN, the MME uses
the EPS bearer QoS parameters to derive the corresponding PDP
context parameters QoS Negotiated (R99 QoS profile), Radio
Priority, Packet Flow Id and TI and includes them in the Session
Management Request. If the UE indicated in the UE Network
Capability it does not support BSS packet flow procedures, then the
MME shall not include the Packet Flow Id. The MME then signals the
Bearer Setup Request (EPS Bearer Identity, EPS Bearer QoS, Session
Management Request, S1-TEID) message to the eNodeB. [0099] 5. The
eNodeB maps the EPS Bearer QoS to the Radio Bearer QoS. It then
signals a RRC Connection Reconfiguration (Radio Bearer QoS, Session
Management Request, EPS RB Identity) message to the UE. The UE
shall store the QoS Negotiated, Radio Priority, Packet Flow Id and
TI, which it received in the Session Management Request, for use
when accessing via GERAN or UTRAN. The UE NAS stores the EPS Bearer
Identity and links the dedicated bearer to the default bearer
indicated by the Linked EPS Bearer Identity (LBI). The UE uses the
uplink packet filter (UL TFT) to determine the mapping of traffic
flows to the radio bearer. The UE may provide the EPS Bearer QoS
parameters to the application handling the traffic flow. The
application usage of the EPS Bearer QoS is implementation
dependent. The UE may not reject the RRC Connection Reconfiguration
on the basis of the EPS Bearer QoS parameters contained in the
Session Management Request in one embodiment. [0100] 6. The UE
acknowledges the radio bearer activation to the eNodeB with a RRC
Connection Reconfiguration Complete message. [0101] 7. The eNodeB
acknowledges the bearer activation to the MME with a Bearer Setup
Response (EPS Bearer Identity, S1-TEID) message. The eNodeB
indicates whether the requested EPS Bearer QoS could be allocated
or not. [0102] The MME shall be prepared to receive this message
either before or after the Session Management Response message
(sent in step 9). [0103] 8. The UE NAS layer builds a Session
Management Response including EPS Bearer Identity. The UE then
sends a Direct Transfer (Session Management Response) message to
the eNodeB. [0104] 9. The eNodeB sends an Uplink NAS Transport
(Session Management Response) message to the MME. [0105] 10. Upon
reception of the Bearer Setup Response message in step 7 and the
Session Management Response message in step 9, the MME acknowledges
the bearer activation to the Serving GW by sending a Create Bearer
Response (EPS Bearer Identity, S1-TEID, User Location Information
(ECGI)) message. [0106] 11. The Serving GW acknowledges the bearer
activation to the PDN GW by sending a Create Bearer Response (EPS
Bearer Identity, S5/S8-TEID, User Location Information (ECGI))
message. [0107] 12. If the dedicated bearer activation procedure
was triggered by a PCC Decision Provision message from the PCRF,
the PDN GW indicates to the PCRF whether the requested PCC decision
(QoS policy) could be enforced or not, allowing the completion of
the PCRF-Initiated IP-CAN Session Modification procedure or the
PCEF initiated IP-CAN Session Modification procedure as defined in
TS 23.203 [6], after the completion of IP-CAN bearer signalling. If
requested by the PCRF the PDN GW indicates User Location
Information and/or UE Time Zone Information to the PCRF as defined
in TS 23.203 [6].
[0108] Next as shown in FIG. 4, a dedicated bearer modification may
be used in place of Steps 15-17. Then SDF context are delivered to
the eNB via Steps 1, 2, 3 and 4. A more complete definition and
description is contained in Clause 5.4.2.1 of TS 23.401.
[0109] Finally, user equipment requested PDN connectivity may be
used to transfer the context via the depicted Steps 4, 5, 6 and 7
to eNB. Steps are defined in Clause 5.10.2 of TS 23.401.
[0110] Referring to FIG. 5, in accordance with another embodiment,
the AMBR can be transferred by user equipment requested PDN
connectivity as shown in FIG. 5. The SDF contexts are delivered to
the eNB via Steps 4, 5, 6 and 7. The steps are defined in Clause
5.10.2 of TS 23.401.
[0111] For the UTRAN/GERAN case, SDF context can be delivered to
the RNC/BSS from GGSN via S-GW and SGSN during PDP context
activation procedure as defined in Clause 9.2 of TS 23.060 and the
PDP context modification procedure as defined in Clause 9.2.3 of TS
23.060.
[0112] There are many possible techniques for detecting congestion.
Generally congestion detection is RAN node implemented. According
to one technique the radio downlink packets may be monitored. If
more packets are going into a given buffer and buffering is going
on faster than what is going out, then congestion can be
detected.
[0113] Referring to FIG. 6, in accordance with one embodiment, a
sequence 40 for handling congestion may be implemented in software,
firmware and/or hardware. In software and firmware embodiments it
may be implemented by computer executed instructions stored in one
or more non-transitory computer readable media such as magnetic,
optical or semiconductor storages.
[0114] The sequence 40 may begin by detecting congestion as
indicated at diamond 42. If congestion is detected, the appropriate
rule for handling the congestion may be located as indicated in
block 44. For example, the AMBR may be reduced to accommodate the
congestion. The AMBR could be reduced for a particular user or a
particular class of service such as video.
[0115] Then the QCI is modified as indicated in block 46 to
communicate the change as indicated in block 46. Next, the AMBR is
adjusted as indicated in block 48.
[0116] Thereafter a check at diamond 50 determines whether the
congestion still exists. If so, the AMBR may be adjusted back to
where it was before the congestion was detected as indicated in
block 52.
[0117] Referring now to FIG. 7, a block diagram of an information
handling system in accordance with one or more embodiments will be
discussed. Information handling system 800 of FIG. 7 may tangibly
embody one or more of any of the network elements or devices as
shown in and described with respect to FIGS. 1 to 6, with greater
or fewer components depending on the hardware specifications of the
particular device or network element. Although information handling
system 800 represents one example of several types of computing
platforms, information handling system 800 may include more or
fewer elements and/or different arrangements of elements than shown
in FIG. 7, and the scope of the claimed subject matter is not
limited in these respects.
[0118] In one or more embodiments, information handling system 800
may include an applications processor 810 and a baseband processor
812. Applications processor 810 may be utilized as a general
purpose processor to run applications and the various subsystems
for information handling system 800. Applications processor 810 may
include a single core or alternatively may include multiple
processing cores wherein one or more of the cores may comprise a
digital signal processor or digital signal processing core.
Furthermore, applications processor 810 may include a graphics
processor or coprocessor disposed on the same chip, or
alternatively a graphics processor coupled to applications
processor 810 may comprise a separate, discrete graphics chip.
Applications processor 810 may include on board memory such as
cache memory, and further may be coupled to external memory devices
such as synchronous dynamic random access memory (SDRAM) 814 for
storing and/or executing applications during operation, and NAND
flash 816 for storing applications and/or data even when
information handling system 800 is powered off. In general, any of
the memory devices of information handling system 800 may comprise
an article of manufacture having instructions stored thereon that
cause a processor of the information handling system 800 to execute
the instructions to implement any method or process wholly or in
part as described herein. Baseband processor 812 may control the
broadband radio functions for information handling system 800.
Baseband processor 812 may store code for controlling such
broadband radio functions in a NOR flash 818. Baseband processor
812 controls a wireless wide area network (WWAN) transceiver 820
which is used for modulating and/or demodulating broadband network
signals, for example for communicating via a Wi-Fi, LTE or WiMAX
network or the like as discussed herein. The WWAN transceiver 820
couples to one or more power amps 822 respectively coupled to one
or more antennas 824 for sending and receiving radio-frequency
signals via the WWAN broadband network. The baseband processor 812
also may control a wireless local area network (WLAN) transceiver
826 coupled to one or more suitable antennas 828 and which may be
capable of communicating via a Wi-Fi, Bluetooth, and/or an
amplitude modulation (AM) or frequency modulation (FM) radio
standard including an IEEE 802.11a/b/g/n standard or the like. It
should be noted that these are merely example implementations for
applications processor 810 and baseband processor 812, and the
scope of the claimed subject matter is not limited in these
respects. For example, any one or more of SDRAM 814, NAND flash 816
and/or NOR flash 818 may comprise other types of memory technology
such as magnetic memory, chalcogenide memory, phase change memory,
or ovonic memory, and the scope of the claimed subject matter is
not limited in this respect.
[0119] In one or more embodiments, applications processor 810 may
drive a display 830 for displaying various information or data, and
may further receive touch input from a user via a touch screen 832
for example via a finger or a stylus. An ambient light sensor 834
may be utilized to detect an amount of ambient light in which
information handling system 800 is operating, for example to
control a brightness or contrast value for display 830 as a
function of the intensity of ambient light detected by ambient
light sensor 834. One or more cameras 836 may be utilized to
capture images that are processed by applications processor 810
and/or at least temporarily stored in NAND flash 816. Furthermore,
applications processor may couple to a gyroscope 838, accelerometer
840, magnetometer 842, audio coder/decoder (CODEC) 844, and/or
global positioning system (GPS) controller 846 coupled to an
appropriate GPS antenna 848, for detection of various environmental
properties including location, movement, and/or orientation of
information handling system 800. Alternatively, controller 846 may
comprise a Global Navigation Satellite System (GNSS) controller.
Audio CODEC 844 may be coupled to one or more audio ports 850 to
provide microphone input and speaker outputs either via internal
devices and/or via external devices coupled to information handling
system via the audio ports 850, for example via a headphone and
microphone jack. In addition, applications processor 810 may couple
to one or more input/output (I/O) transceivers 852 to couple to one
or more I/O ports 854 such as a universal serial bus (USB) port, a
high-definition multimedia interface (HDMI) port, a serial port,
and so on. Furthermore, one or more of the I/O transceivers 852 may
couple to one or more memory slots 856 for optional removable
memory such as secure digital (SD) card or a subscriber identity
module (SIM) card, although the scope of the claimed subject matter
is not limited in these respects.
[0120] Referring now to FIG. 8, an isometric view of an information
handling system 900 of FIG. 7 that optionally may include a touch
screen in accordance with one or more embodiments will be
discussed. FIG. 8 shows an example implementation of information
handling system 800 of FIG. 7 tangibly embodied as a cellular
telephone, smartphone, or tablet type device or the like. The
information handling system 900 may comprise a housing 910 having a
display 830 which may include a touch screen 832 for receiving
tactile input control and commands via a finger or fingers 916 of a
user and/or a via stylus 918 to control one or more applications
processors 810. The housing 910 may house one or more components of
information handling system 800, for example one or more
applications processors 810, one or more of SDRAM 814, NAND flash
816, NOR flash 818, baseband processor 812, and/or WWAN transceiver
820. The information handling system 800 further may optionally
include a physical actuator area 920 which may comprise a keyboard
or buttons for controlling information handling system via one or
more buttons or switches. The information handling system 900 may
also include a memory port or slot 856 for receiving non-volatile
memory such as flash memory, for example in the form of a secure
digital (SD) card or a subscriber identity module (SIM) card.
Optionally, the information handling system 800 may further include
one or more speakers and/or microphones 924 and a connection port
854 for connecting the information handling system 900 to another
electronic device, dock, display, battery charger, and so on. In
addition, information handling system 800 may include a headphone
or speaker jack 928 and one or more cameras 836 on one or more
sides of the housing 910. It should be noted that the information
handling system 800 of FIG. 8 may include more or fewer elements
than shown, in various arrangements, and the scope of the claimed
subject matter is not limited in this respect.
[0121] The following clauses and/or examples pertain to further
embodiments:
[0122] One example of an embodiment may be a method including in
response to detection of radio access network user plane
congestion, changing a first priority of at least one of a
particular user or data type, using a service data flow quality of
service indicator to signal said priority change, and in response
to detection of the termination of said congestion, changing
priority back to the first priority. The method may include
changing a maximum bit rate in response to said congestion. The
method may also include providing a service data flow quality of
service based rule for handling congestion. The method may also
include providing said rule as part of PDP context or EPS bearer
context. The method may also include specifying a maximum
uncongested and congested bit rate for a service data flow. The
method may also include using an attach procedure to signal said
priority change. The method may also include using dedicated bearer
activation to signal the priority change. The method may also
include using dedicated bearer modification to signal the priority
change. The method may also include using user equipment requested
packet data network connectivity to signal the priority change.
[0123] In another example, one or more non-transitory computer
readable media may store instructions to implement a sequence to
signal radio access network user plane congestion using a service
data flow quality of service indicator, reduce a bit rate in
response to said service class indicator, and apply a service data
flow quality of service based rule for handling congestion. The
medium may also include decreasing a maximum bit rate in response
to said congestion. The medium may also include providing a service
data flow quality of service based rule for handling congestion.
The medium may also include providing said rule as part of PDP
context or EPS bearer context. The medium may also include
specifying a maximum uncongested and congested bit rate for a
service data flow. The medium may also include using an attach
procedure to signal said priority change. The medium may also
include using dedicated bearer activation to signal the priority
change. The medium may also include using dedicated bearer
modification to signal the priority change. The medium may also
include using user equipment requested packet data network
connectivity to signal the priority change.
[0124] Another example may be an apparatus that includes a
processor to receive an indication of user plane congestion and, in
response, locate a rule for handling the congestion, and an
interface to transmit an indicator to initiate a bit rate change in
response to said congestion. The apparatus may also transmit an
indicator to change a maximum bit rate in response to said
congestion. The apparatus may also transmit a service class
indicator to initiate a bit rate change. The apparatus may also
locate a service data flow based rule for handling congestion. The
apparatus may also use an attach procedure to signal said priority
change. The apparatus may also use dedicated bearer activation to
initiate the change. The apparatus may also use dedicated bearer
modification. The apparatus may also use user equipment requested
packet data network connectivity to initiate the change. The
apparatus may also use touch screen display, keyboard, antenna, and
an application processor.
[0125] References throughout this specification to "one embodiment"
or "an embodiment" mean that a particular feature, structure, or
characteristic described in connection with the embodiment is
included in at least one implementation encompassed within the
present disclosure. Thus, appearances of the phrase "one
embodiment" or "in an embodiment" are not necessarily referring to
the same embodiment. Furthermore, the particular features,
structures, or characteristics may be instituted in other suitable
forms other than the particular embodiment illustrated and all such
forms may be encompassed within the claims of the present
application.
[0126] While a limited number of embodiments have been described,
those skilled in the art will appreciate numerous modifications and
variations therefrom. It is intended that the appended claims cover
all such modifications and variations as fall within the true
spirit and scope of this disclosure.
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