U.S. patent application number 13/388701 was filed with the patent office on 2012-05-24 for method and system for performing a local switching of a local call.
This patent application is currently assigned to ZTE CORPORATION. Invention is credited to Jing Li, Quanjun Tao, Zhenhua Xie.
Application Number | 20120129531 13/388701 |
Document ID | / |
Family ID | 43585880 |
Filed Date | 2012-05-24 |
United States Patent
Application |
20120129531 |
Kind Code |
A1 |
Tao; Quanjun ; et
al. |
May 24, 2012 |
METHOD AND SYSTEM FOR PERFORMING A LOCAL SWITCHING OF A LOCAL
CALL
Abstract
The present invention provides a method for implementing local
call local switch, which includes that: a source MSC receives a
handover request from a source BSS; the source MSC transfers a
local reference to a destination BSS; and the destination BSS
judges whether local switch can be triggered according to the
received local reference, and executes the local switch if a
judgment result is that the local switch can be triggered. The
present invention further provides a system for implementing local
call local switch, which includes a MSC and a BSS, wherein the MSC
includes a MSC request module and a MSC processing module, and the
BSS includes a BSS request module and a BSS processing module, so
as to support for implementing the local call local switch in a
handover scenario. The method and the system solve the problem of
unsuccessful local switch due to BSS connecting multiple MSCs.
Inventors: |
Tao; Quanjun; (Shenzhen
City, CN) ; Xie; Zhenhua; (Shenzhen City, CN)
; Li; Jing; (Shenzhen City, CN) |
Assignee: |
ZTE CORPORATION
Shenzhen City, Guangdong Province
CN
|
Family ID: |
43585880 |
Appl. No.: |
13/388701 |
Filed: |
December 25, 2009 |
PCT Filed: |
December 25, 2009 |
PCT NO: |
PCT/CN2009/076090 |
371 Date: |
February 3, 2012 |
Current U.S.
Class: |
455/436 |
Current CPC
Class: |
H04W 92/22 20130101;
H04W 28/06 20130101; H04Q 3/0016 20130101; H04W 92/045 20130101;
H04W 76/12 20180201 |
Class at
Publication: |
455/436 |
International
Class: |
H04W 36/00 20090101
H04W036/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 12, 2009 |
CN |
200910167321.X |
Claims
1. A method for implementing local call local switch, comprising: a
source Mobile Switch Center (MSC) receiving a handover required
message from a source Base Station System (BSS); the source MSC
transferring a local reference of an associated call to a
destination BSS; and the destination BSS judging whether local
switch can be triggered according to the received local reference,
and executing the local switch if a judgment result is that the
local switch can be triggered.
2. The method according to claim 1, wherein the source MSC
transfers the local reference to the destination BSS only when a
user meets a local switch condition.
3. The method according to claim 2, wherein the user meeting the
local switch condition refers that the user does not have a session
communicating with other users and a local switch user management
strategy of an operator is met.
4. The method according to claim 1, wherein the local reference
refers to a local reference allocated by a MSC at a calling side in
a process of establishing a call, the allocated local references
are different for different calls, and the source MSC obtains and
stores the local reference in the process of establishing the
call.
5. The method according to claim 1, wherein the step of the source
MSC transferring the local reference to the destination BSS
comprises: the source MSC transferring the local reference to a
destination MSC; and the destination MSC sending the local
reference to the destination BSS.
6. The method according to claim 5, wherein the step of the
destination BSS judging whether the local switch can be triggered
according to the received local reference comprises: the
destination BSS finding whether there is a same local reference in
a data area of the destination BSS or a corresponding data table
according to the local reference after receiving the local
reference sent by the destination MSC, and if there is the same
local reference, the destination BSS determining that the local
switch can be triggered.
7. The method according to claim 6, before the step of the
destination BSS judging whether the local switch can be triggered
according to the received local reference, further comprising: the
destination BSS receiving a handover completion message sent by a
user.
8. The method according to claim 1, after the step of the
destination BSS executing the local switch, further comprising: the
destination BSS transferring an execution result to the source MSC
and a destination MSC.
9. The method according to claim 8, wherein the execution result
includes a handover completion message, and the handover completion
message includes a local switch success indication.
10. The method according to claim 8, after the step of the
destination BSS executing the local switch, further comprising:
after receiving the execution result, if the local switch succeeds,
the source MSC releasing a circuit with the source BSS; and after
receiving the execution result, if the local switch succeeds, the
source MSC releasing a circuit with the destination BSS.
11. A system for implementing local call local switch, comprising a
Mobile Switch Center (MSC) and a Base Station System (BSS), wherein
the MSC comprises a MSC request module and a MSC processing module,
and the BSS comprises a BSS request module and a BSS processing
module, wherein the MSC request module is configured to: receive a
handover required message sent by a source BSS; select a
destination MSC according to the handover required message; and
transfer a local reference of an associated call to the destination
MSC; the MSC processing module is configured to: transfer a local
reference of an associated call transferred by a source MSC to a
destination BSS; and judge whether a correspondent user of a
handover user meets a local switch condition; the BSS request
module is configured to: send a handover required message to the
source MSC; the BSS processing module is configured to: receive the
local reference of the associated call transferred by the source
MSC; and judge whether local switch can be triggered, and execute
the local switch if a judgment result is that the local switch can
be triggered, and loop users at both sides to a local voice bearer
connection of the BSS.
12. The system according to claim 11, wherein the MSC request
module transfers the local reference only when the handover user
meets the local switch condition, wherein, the user meeting the
local switch condition refers that the user does not have a session
communicating with other users and a local switch user management
strategy of an operator is met.
13. The system according to claim 12, wherein the local reference
refers a local reference allocated by a source MSC in a process of
establishing a call, and the allocated local references are
different for different calls, the MSC request module is further
configured to: obtain and store the local reference in the process
of establishing the call.
14. The system according to claim 13, wherein the BSS processing
module is further configured to: find whether there is a same local
reference in a data area of this BSS or a corresponding data table
according to the local reference, and if there is the same local
reference, determine that the local switch can be triggered.
15. The system according to claim 11, wherein the BSS processing
module is further configured to: receive a handover completion
message sent by a user.
16. The system according to claim 11, wherein the BSS processing
module is further configured to: transfer an execution result to
the source MSC and the destination MSC after completing the local
switch; wherein, the execution result includes a handover
completion message including a local switch success indication.
17. The system according to claim 16, wherein the MSC request
module is further configured to: release a circuit with the source
BSS after receiving the execution result; the MSC processing module
is configured to: release a circuit with the destination BSS after
receiving the execution result.
Description
TECHNICAL FIELD
[0001] The invention relates to the communication field, and more
specifically, to a method and a system for performing Local Call
Local Switch (LCLS) in a circuit switched domain.
BACKGROUND OF THE RELATED ART
[0002] The circuit switch technology adopted by the mobile network
such as Global System for Mobile communications (GSM) and Universal
Mobile Telecommunications System (UMTS) and so on, called as the
Circuit Switched (CS) domain, can provide the basic voice services
and the supplementary services based on voice services for
users.
[0003] Some places in the world such as Africa, South America and
South Asia and so on, lack the fast and reliable transmission
resources or have the high transmission cost, which brings
difficulties in the network and service deployment for operators.
However, most of calls in the mobile network are local calls in
those places according to data statistics, and these calls are
generated in the same Base Station System (BSS). For the local
call, if the local switch technology (the voice data are looped in
BSS) is adopted, the transmission resources of the A interface
between BBS and the Mobile Switch Center (MSC) in the core
network.
[0004] FIG. 1 is a schematic diagram of the traditional voice call,
in which the User Equipment (UE) accesses BSS and MSC through the
circuit switched domain. When UE1 calls UE2, UE1 sends a call
establishment request to the its accessed MSC through BSS; MSC
finds the called UE2 according to the location information of the
UE2 access, and notifies BSS of establishing the radio bearers
connecting UE1 and UE2, and the bearers of UE1 and UE2 are
respectively established between BSS and MSC; the bearers at the
both sides of MSC are looped to ensure the voice communication
between UE1 and UE2.
[0005] FIG. 2 is a schematic diagram of the voice call adopting the
local call local switch technology. Compared with FIG. 1, when
receiving the call establishment request of UE1, MSC judges whether
UE1 and UE2 belong to one BSS according to a cell, and if UE1 and
UE2 belong to the same one BSS, MSC notifies BSS of performing the
local switch; the bearer loops of UE1 and UE2 are performed at the
BSS side, which will save the bearer resource, i.e., bearer
resource of the A interface between BSS and MSC.
[0006] FIG. 3 is a signaling flowchart adopting the local call
local switch technology in FIG. 2, comprising the following steps
of:
[0007] 301, UE1 and UE2 initiate calling in the same BSS, and
establish interconnection through the MSC in the core network, and
MSC allocates circuit numbers or a call identifiers between BSS and
MSC for calling UE1 and called UE2;
[0008] 302, the called UE2 replies in the ringing state, and sends
a called reply message to MSC through BSS;
[0009] 303, MSC sends the called reply message to the calling UE1,
and notifies UE1 of the call connecting;
[0010] 304, MSC judges whether this call is a local call belonging
to one BSS or not according to the current location information of
the calling UE1 and the called UE2;
[0011] 305, if it is the local call belonging to one BSS, MSC sends
the local switch command message including the circuit numbers or
the call identifiers between BSS and MSC allocated for calling UE1
and called UE2 in step 301 to BSS to notify BSS to perform the
local switch;
[0012] 306, BSS receives the local switch command message,
associates with two ongoing communication sessions according to the
circuit numbers or the call identifiers of the calling and the
called in the local switch command message, and loop their voice
data bearers to implement to switch the voice bearers within
BSS;
[0013] 307, BSS sends the local switch success message to MSC after
the local switch succeeding;
[0014] 308, MSC notifies BSS of releasing the voice bearer
connection between BSS and MSC after receiving the local switch
success message, and releases the bearer connection of the A
interface.
[0015] With respect to the analysis in above steps, if the calling
UE1 accesses MSC1 through BSS and the called UE2 accesses MSC2
through BSS in a scenario of BBS connecting multiple MSCs as shown
in FIG. 4, although the calling and the called initiates calling in
the same BSS, the calling and the called respectively access the
different MSCs, thereby leading to whichever of MSC1 accessed by
the calling UE1 and MSC2 accessed by the called UE2 being unable to
judge whether this call is the local call according to location
information of the calling and the called, and finally leading to a
problem that the local call cannot perform the local switch.
SUMMARY OF THE INVENTION
[0016] The object of the present invention is to provide a method
and a system for implementing local call local switch, to solve the
problem of unsuccessful local switch caused by the BSS connecting
multiple MSCs.
[0017] The present invention is to provide a method for
implementing local call local switch, which comprises:
[0018] a source MSC receiving a handover required message from a
source BSS;
[0019] the source MSC transferring a local reference of an
associated call to a destination BSS; and
[0020] the destination BSS judging whether local switch can be
triggered according to the received local reference, and executing
the local switch if a judgment result is that the local switch can
be triggered.
[0021] Furthermore, in the above method,
[0022] the source MSC transfers the local reference to the
destination BSS only when a user meets a local switch
condition.
[0023] Furthermore, in the above method, the user meeting the local
switch condition refers that the user does not have a session
communicating with other users and a local switch user management
strategy of an operator is met.
[0024] Furthermore, in the above method, the local reference refers
to a local reference allocated by a MSC at a calling side in a
process of establishing a call, the allocated local references are
different for different calls, and the source MSC obtains and
stores the local reference in the process of establishing the
call.
[0025] Furthermore, in the above method, the step of the source MSC
transferring the local reference to the destination BSS
comprises:
[0026] the source MSC transferring the local reference to a
destination MSC; and
[0027] the destination MSC sending the local reference to the
destination BSS.
[0028] Furthermore, in the above method, the step of the
destination BSS judging whether the local switch can be triggered
according to the received local reference comprises:
[0029] the destination BSS finding whether there is a same local
reference in a data area of the destination BSS or a corresponding
data table according to the local reference after receiving the
local reference sent by the destination MSC, and if there is the
same local reference, the destination BSS determining that the
local switch can be triggered.
[0030] Furthermore, in the above method, before the step of the
destination BSS judging whether the local switch can be triggered
according to the received local reference, the method further
comprises:
[0031] the destination BSS receiving a handover completion message
sent by a user.
[0032] Furthermore, in the above method, after the step of the
destination BSS executing the local switch, the method further
comprises:
[0033] the destination BSS transferring an execution result to the
source MSC and a destination MSC.
[0034] Furthermore, in the above method, the execution result
includes a handover completion message, and the handover completion
message includes a local switch success indication.
[0035] Furthermore, in the above method, after the step of the
destination BSS executing the local switch, the method further
comprises:
[0036] after receiving the execution result, if the local switch
succeeds, the source MSC releasing a circuit with the source BSS;
and
[0037] after receiving the execution result, if the local switch
succeeds, the source MSC releasing a circuit with the destination
BSS.
[0038] The present invention further provides a system for
implementing local call local switch, and the system comprises a
Mobile Switch Center (MSC) and a Base Station System (BSS), wherein
the MSC comprises a MSC request module and a MSC processing module,
and the BSS comprises a BSS request module and a BSS processing
module, wherein
[0039] the MSC request module is configured to: [0040] receive a
handover required message sent by a source BSS; [0041] select a
destination MSC according to the handover required message; and
[0042] transfer a local reference of an associated call to the
destination MSC;
[0043] the MSC processing module is configured to: [0044] transfer
a local reference of an associated call transferred by a source MSC
to a destination BSS; and [0045] judge whether a correspondent user
of a handover user meets a local switch condition;
[0046] the BSS request module is configured to: [0047] send a
handover required message to the source MSC;
[0048] the BSS processing module is configured to: [0049] receive
the local reference of the associated call transferred by the
source MSC; and [0050] judge whether local switch can be triggered,
and execute the local switch if a judgment result is that the local
switch can be triggered, and loop users at both sides to a local
voice bearer connection of the BSS.
[0051] Furthermore, in the above system, the MSC request module
transfers the local reference only when the handover user meets the
local switch condition, wherein
[0052] the user meeting the local switch condition refers that the
user does not have a session communicating with other users and a
local switch user management strategy of an operator is met.
[0053] Furthermore, in the above system, the local reference refers
a local reference allocated by a source MSC in a process of
establishing a call, and the allocated local references are
different for different calls,
[0054] the MSC request module is further configured to: obtain and
store the local reference in the process of establishing the
call.
[0055] Furthermore, in the above system, the BSS processing module
is further configured to:
[0056] find whether there is a same local reference in a data area
of this BSS or a corresponding data table according to the local
reference, and
[0057] if there is the same local reference, determine that the
local switch can be triggered.
[0058] Furthermore, in the above system, the BSS processing module
is further configured to: receive a handover completion message
sent by a user.
[0059] Furthermore, in the above system, the BSS processing module
is further configured to: transfer an execution result to the
source MSC and the destination MSC after completing the local
switch; wherein,
[0060] the execution result includes a handover completion message
including a local switch success indication.
[0061] Furthermore, in the above system,
[0062] the MSC request module is further configured to: release a
circuit with the source BSS after receiving the execution
result;
[0063] the MSC processing module is configured to: release a
circuit with the destination BSS after receiving the execution
result.
[0064] Compared with the related art, the invention provides a
method and a system for performing local call local switch, thereby
solving the problem of unsuccessful local switch due to BSS
connecting multiple MSCs in the handover scenario.
BRIEF DESCRIPTION OF DRAWINGS
[0065] FIG. 1 is a schematic diagram of the traditional voice
call;
[0066] FIG. 2 is a schematic diagram of the voice call adopting the
local call local switch technology;
[0067] FIG. 3 is a signaling flowchart adopted the local call local
switch technology in FIG. 2;
[0068] FIG. 4 is a schematic diagram of the scenario in which BSS
connects multiple MSCs;
[0069] FIG. 5 is a flowchart of the embodiment for implementing the
local switch in the scenario that the calling user and the called
user are located under different BSSs and the different MSCs
according to the present invention;
[0070] FIG. 6 is a schematic diagram of the system for implementing
local call local switch according to the present invention.
PREFERRED EMBODIMENTS OF THE PRESENT INVENTION
[0071] Below the present invention will be further illustrated in
detail in combination with drawings and embodiments.
[0072] FIG. 5 is a flowchart of the embodiment for implementing the
local switch in the scenario that the calling user and the called
user are located under different BSSs and the different MSCs
according to the present invention; the calling UE1 and the called
UE2 respectively belong to the different BSSs and the different
MSCs in the present embodiment, wherein UE1 accesses MSC1 through
BSS1, and UE2 accesses MSC2 through BSS2. In a call process of UE1
and UE2, UE1 hands over to BSS2, and BSS2 triggers the local switch
according to the local reference. As shown in FIG. 5, wherein BSS1
is the source BSS, BSS2 is the destination BSS, MSC1 is the source
MSC, and MSC2 is the destination MSC. The present embodiment
comprises the following steps of:
[0073] 501, UE1 and UE2 are calling, BSS1 decides to hand over the
UE1 session to BSS2 according to radio measurement reports, and
BSS1 sends the handover required message to MSC1, and if BSS1 has
stored the local reference generated in a the process of
establishing the call, the handover required message can include
the local reference;
[0074] 502, MSC1 receives the handover required message sent by
BSS1, judges whether the current user UE1 meets the local switch
condition, that is, judges whether UE1 currently has a session
communicating session with other users, whether a local switch user
management strategy of the operator is met, and whether the
monitoring point, i.e., the monitoring service of MSC, is
configured, and if UE1 simultaneously meets the conditions that
there is not the session communicating with other users currently,
the local switch user management strategy of the operator is met,
and the monitoring point, namely the monitoring service of MSC is
configured, or, if UE1 at least meets the conditions that there is
not the session communicating with other users currently and the
local switch user management strategy of the operator is met, then
the local switch condition is met;
[0075] if the local switch condition is met, MSC1 selects the
destination MSC2 according to the address of the destination cell
of the handover in the handover required, and sends the handover
request message including the local reference to MSC2;
[0076] 503, MSC2 sends the handover request message to BSS2 to
notify BSS2 to allocate the ground circuit and the air interface
resources after receiving the handover request message, and the
local reference from MSC1 is forwarded in the handover request
message;
[0077] 504, BSS2 stores the local reference, allocates the air
interface and the ground circuit resources, allocates the handover
numbers, and returns the handover reply message to MSC2 after
completing the allocation;
[0078] 505, MSC2 returns the handover reply message including the
handover numbers allocated by MSC2 to MSC1;
[0079] 506, MSC1 establishes the interoffice circuit bearer with
MSC2 according to the handover number;
[0080] 507, MSC1 sends the handover command to UE1 through BSS1 to
notify UE1 to hand over to BSS2;
[0081] 508, UE1 sends a handover completion message to BSS2 after
completing the handover;
[0082] 509, BSS2 judges whether the local switch can be triggered
for users UE1 and UE2 according to the local reference, wherein the
judging method as follows:
[0083] BSS2 perceives that there are two same local references, and
finds whether there is a same local reference in a data area of
BSS2 or a corresponding data table according to the local reference
(i.e., the local reference from MSC1 is forwarded by MSC2 through
the handover request message) stored in step 504, and if there is
the same local reference, then it is determined that the local
switch can be triggered.
[0084] If users UE1 and UE2 can trigger the local switch, BSS2
executes the local switch, and UE1 and UE2 are looped to the voice
bearer connection of BSS,
[0085] BSS2 sends the handover completion message including the
local switch success indication to MSC2 after successfully
executing the local switch;
[0086] 510, MSC2 sends the handover completion message including
the local switch success indication sent by BSS2 to MSC1;
[0087] 511, BSS2 sends the local switch completion message to MSC2
at the same time;
[0088] 512, MSC1 records the local switch success indication after
receiving the handover completion message to notify BSS1 to clear
the air interface resources and release the ground circuit
connecting with BSS1; and
[0089] 513, MSC2 releases the ground circuit with BSS2.
[0090] In other embodiments, the step 511 is an optional step.
[0091] FIG. 6 is a schematic diagram of the system for implementing
local call local switch according to the present invention. The
system comprises MSC and BSS, wherein MSC has a communication
connection with BSS. The MSC comprises an MSC request module and an
MSC processing module, and the BSS comprises a BSS request module
and a BSS processing module, wherein
[0092] the MSC request module is configured to: receive a handover
required message sent by a source BSS; select a destination MSC
according to the handover required message; and transfer local
references of associated calls to the destination MSC;
[0093] the MSC processing module is configured to: transfer the
local references of associated calls transferred by the source MSC
to the destination BSS; and judge whether a correspondent user of
the handover user meets a local switch condition;
[0094] the BSS request module is configured to: send the handover
required message to the source MSC;
[0095] the BSS processing module is configured to: receive the
local references of associated calls transferred by the source MSC;
and judge whether the local switch can be triggered, execute the
local switch if the judgment result is that the local switch can be
triggered, and loop users at both sides to the voice bearer
connection of this BSS;
[0096] thereby supporting for implementing the local call local
switch in a handover scenario.
[0097] Further, the MSC request module transfers the local
reference only when the handover user meets the local switch
condition, wherein the user meeting the local switch condition
refers that the user does not have a session communicating session
with other users at present and the local switch user management
strategy of the operator is met.
[0098] Further, the local reference refers that the local reference
allocated by the source MSC in a process of establishing a call,
and the allocated local references are different for different
calls,
[0099] and the MSC request module is further configured to: obtain
and store the local reference in the process of establishing the
call.
[0100] Further, the BSS processing module is further configured to:
find whether there are the same local references in a data area of
this BSS or a corresponding data table according to the local
references; if there is the same local reference, it is determined
that the local switch can be triggered.
[0101] Further, the BSS processing module is further configured to:
receive a handover completion message sent by the user.
[0102] Further, the BSS processing module is further configured to:
transfer an execution result to the source MSC and the destination
MSC after completing the local switch; wherein,
[0103] the execution result includes the handover completion
message including the local switch success indication.
[0104] Further, the MSC request module is further configured to:
release the circuit with the source BSS after receiving the
execution result;
[0105] the MSC processing module is further configured to: release
the circuit with the destination BSS after the receiving the
execution result.
[0106] Of course, the present invention can also have a variety of
other embodiments, and a person skilled in the art can make various
corresponding changes and transformations according to the present
invention without departing from the spirit and essence of the
present invention, however, these corresponding changes and
transformations should fall into the protection scope of appended
claims in the present invention.
INDUSTRIAL APPLICABILITY
[0107] The invention provides a method and a system for
implementing local call local switch, which solves the problem of
unsuccessful local switch caused by a BSS connecting multiple
MSCs
* * * * *