CN104754767B

CN104754767B - State updating method and equipment

Info

Publication number: CN104754767B
Application number: CN201310726560.0A
Authority: CN
Inventors: 舒林; 吴晓波; 朱浩鹏
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2013-12-25
Filing date: 2013-12-25
Publication date: 2019-03-01
Anticipated expiration: 2033-12-25
Also published as: CN104754767A

Abstract

The embodiment of the present invention provides a kind of state updating method and equipment.Method includes: the circuit domain dropping CSFB service ending that moving exchanging center MSC/VLR Visitor Location Register VLR determines user equipment (UE)；Delete the first SGs association of the UE on the MSC/VLR.The embodiment of the present invention deletes the SGs association of the local UE by MSC/VLR after the CSFB service ending for determining UE, to in the MT call request of the subsequently received UE, it can directly initiate to UE to eat dishes without rice or wine to page due to local be associated with there is no the SGs of the UE, multiple time-out is avoided to retransmit, the delay time for reducing MT calling, substantially increase the probability of MT access success.

Description

State updating method and device

Technical Field

The present invention relates to communications technologies, and in particular, to a method and a device for updating a status.

Background

Based on The SGs interface function between a Mobile Switching Center (MSC)/Visitor Location Register (VLR) and a Mobility Management Entity (MME) in a Second Generation/Third Generation (2G/3G) network, a Third Generation partnership Project (3 rd Generation partnership Project, 3 GPP) proposes a Circuit domain Fallback (CSFB) technology and an SGs Short Message Service (SMS) SGs technology.

In the CSFB and SMS over SGs mechanism, a User Equipment (User Equipment, abbreviated UE) residing in an Evolved Universal Mobile telecommunications System terrestrial Radio access Network (Evolved Universal Mobile telecommunications System terrestrial Radio access Network, abbreviated E-UTRAN) and supporting CSFB and/or SMS over SGs needs to initiate a joint registration procedure to achieve simultaneous registration of an Evolved Packet Core Network (Evolved Packet Core Network, abbreviated EPC) Packet Switched (PS) domain and a 2G/3G Network CS domain, and after the joint registration is successful, the states of the registered MSC/VLR and the SGs of the UE are both active states. In a typical CSFB scenario, after the UE drops back to the 2G/3G network and completes a CS voice call, the UE continues to stay in the 2G/3G network, and at this time, if the MSC/VLR receives a downlink termination (MT) call request to the UE, since the state of SGs association of the UE on the MSC/VLR is an active state, the MSC/VLR may initiate an SGs interface paging to the MME and start an SGs paging timer; because the SGs associated state of the UE on the MME is an activated state, the MME initiates an air interface paging to the UE; but because the UE does not return to the E-UTRAN, the air interface paging is overtime until the SGs paging is overtime, the MSC/VLR retransmits overtime according to the configured retransmission times, and after the retransmission is finished, the MSC/VLR directly initiates the air interface paging of the UE from the A/Iu interface of the 2G/3G network; the UE is paged in and establishes an MT voice call. In the process, the MSC/VLR and the SGs association of the UE on the MME are kept in an activated state, for the follow-up MT call to the UE, the MSC/VLR firstly initiates SGs interface paging to the MME, the MME then initiates air interface paging to the UE, and the MSC/VLR then initiates the air interface paging to the UE from an A/Iu interface of the 2G/3G network until the timeout retransmission is completed.

Disclosure of Invention

Embodiments of the present invention provide a state updating method and device, so as to solve the problem that in the existing CSFB scenario, after a UE drops back to a 2G/3G network to complete a CS voice call, the UE continues to stay in the 2G/3G network, which causes a long delay for each MT call subsequently, and greatly increases the probability of MT call failure.

In a first aspect, an embodiment of the present invention provides a state updating method, including:

the mobile switching center MSC/VLR determines that the circuit switched fallback CSFB service of the user equipment UE is finished;

and deleting the first SGs association of the UE on the MSC/VLR.

According to the first aspect, in a first possible implementation manner of the first aspect, after the mobile switching center MSC/visitor location register VLR determines that a circuit switched fallback CSFB service of a user equipment UE is ended, the method further includes:

the MSC/VLR sends a separation request message to a Mobile Management Entity (MME), wherein the MME is associated with the first SGs association, the separation request message is used for indicating the MME to delete a second SGs association of the UE on the MME, and the MSC/VLR is associated with the second SGs association.

According to the first aspect, in a second possible implementation manner of the first aspect, after the mobile switching center MSC/visitor location register VLR determines that a circuit switched fallback CSFB service of a user equipment UE is ended, the method further includes:

the MSC/VLR sends a release request message to a Mobility Management Entity (MME), the MME associates the associated MME with the first SGs, the release request message contains a first reason value, and the first reason value is used for indicating the CSFB service of the UE to be ended by the MME.

According to the first aspect, in a third possible implementation manner of the first aspect, before the deleting the first SGs association of the UE on the MSC/VLR, the method further includes:

the MSC/VLR sends a CSFB service ending notification message to a Mobile Management Entity (MME), wherein the MME is associated with the first SGs;

the deleting the first SGs association of the UE on the MSC/VLR includes:

and deleting the first SGs association according to the feedback of the MME.

According to a third possible implementation manner of the first aspect, in a fourth possible implementation manner of the first aspect, after the MSC/VLR sends a CSFB service end notification message to a mobility management entity MME, the method further includes:

receiving a detachment indication message sent by the MME;

the deleting the first SGs association according to the feedback of the MME includes:

and deleting the first SGs association according to the separation indication message.

According to a third possible implementation manner of the first aspect, in a fifth possible implementation manner of the first aspect, after the MSC/VLR sends a CSFB service end notification message to a mobility management entity MME, the method further includes:

sending a paging request message to the MME;

receiving an indication message sent by the MME after the UE is determined not to return to a Long Term Evolution (LTE) network after the CSFB service is finished;

and deleting the first SGs association state according to the indication message.

According to a fifth possible implementation manner of the first aspect, in a sixth possible implementation manner of the first aspect, the indication message is a paging rejection message, where the paging rejection message includes a second cause value, and the second cause value is used to indicate separation from an evolved packet system EPS service international mobile subscriber identity IMSI;

deleting the first SGs association according to the indication message, including:

deleting the first SGs association according to the second cause value in the paging rejection message.

According to a fifth possible implementation manner of the first aspect, in a seventh possible implementation manner of the first aspect, the indication message is a separation indication message;

According to a fourth possible implementation manner or the seventh possible implementation manner of the first aspect, in an eighth possible implementation manner of the first aspect, the detach indication message includes a detach type, and the detach type is detach from an EPS service IMSI.

According to any one of the fifth to eighth possible implementation manners of the first aspect, in a ninth possible implementation manner of the first aspect, the method further includes: and initiating air interface paging to the UE.

According to any one of the third to ninth possible implementation manners of the first aspect, in a tenth possible implementation manner of the first aspect, the CSFB service end notification message is a release request message, where the release request message includes a first cause value, and the first cause value is used to indicate that the CSFB service of the UE is ended by the MME.

According to the first aspect or any one of the foregoing possible implementation manners of the first aspect, in an eleventh possible implementation manner of the first aspect, the deleting a first SGs association of the UE on the MSC/VLR includes:

setting a state of the first SGs association to null; or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

and if the state associated with the first SGs is an activated state, setting the state associated with the first SGs to be a deactivated state.

According to the first aspect or any one of the foregoing possible implementation manners of the first aspect, in a twelfth possible implementation manner of the first aspect, the CSFB service includes: circuit switched CS voice service; or, CS video services; or, a CS location service; alternatively, the CS supplements the service.

In a second aspect, an embodiment of the present invention provides a status updating method, including:

a mobility management entity MME receives a circuit switched fallback CSFB service end notification message sent by a mobile switching center MSC/visitor location register VLR, wherein the MSC/VLR is associated with a first SGs association of user equipment UE on the MME, and the CSFB service end notification message is sent by the MSC/VLR when the CSFB service of the UE is determined to be ended;

deleting the first SGs association.

According to the second aspect, in a first possible implementation manner of the second aspect, the CSFB service termination notification message is a detach request message, and the detach request message is used to instruct the MME to delete the first SGs association.

According to the second aspect, in a second possible implementation manner of the second aspect, the CSFB service end notification message is a release request message, where the release request message includes a first cause value, and the first cause value is used to indicate that the CSFB service of the UE ends.

According to the second aspect or the second possible implementation manner of the second aspect, in a third possible implementation manner of the second aspect, after the MME receives a circuit switched fallback CSFB service end notification message sent by a mobile switching center MSC/visitor location register VLR, the method further includes:

and sending a separation indication message to the MSC/VLR, wherein the separation indication message is used for indicating the MSC/VLR to delete the second SGs association of the UE on the MSC/VLR.

According to the second aspect or the second possible implementation manner of the second aspect, in a fourth possible implementation manner of the second aspect, before deleting the first SGs association, the method further includes:

and determining that the UE does not return to the LTE network after the CSFB service is finished.

According to a fourth possible implementation manner of the second aspect, in a fifth possible implementation manner of the second aspect, after the MME receives a circuit switched fallback CSFB service end notification message sent by a mobile switching center MSC/a visitor location register VLR, the method further includes:

if the first SGs association exists on the MME, setting an unreturned indication, wherein the unreturned indication is used for indicating that the UE does not return to an LTE network after the CSFB service is finished.

According to a fifth possible implementation manner of the second aspect, in a sixth possible implementation manner of the second aspect, the method further includes:

receiving a paging request message sent by the MSC/VLR;

if the UE is in an idle state, the MME initiates an idle paging to the UE and starts an idle paging timer;

the determining that the UE does not return to the LTE network after the CSFB service is ended includes:

and if the air interface paging is overtime and the non-regression indication exists, determining that the UE does not regress to the LTE network after the CSFB service is ended.

According to the fifth or sixth possible implementation manner of the second aspect, in a seventh possible implementation manner of the second aspect, after the MME receives a circuit switched fallback CSFB service end notification message sent by a mobile switching center MSC/visitor location register VLR, the method further includes:

and starting a regression timer according to the CSFB service end notification message.

According to a seventh possible implementation manner of the second aspect, in an eighth possible implementation manner of the second aspect, the method further includes:

and if a paging request message sent by the MSC/VLR is received, or the UE is determined to return to the LTE network after the CSFB service is finished, stopping the return timer.

According to the seventh or eighth possible implementation manner of the second aspect, in a ninth possible implementation manner of the second aspect, the determining that the UE does not return to the long term evolution LTE network after the CSFB service is ended includes: and if the regression timer is overtime and the non-regression indication exists, determining that the UE does not regress to the LTE network after the CSFB service is finished.

In a tenth possible implementation manner of the second aspect, according to any one of the fifth to ninth possible implementation manners of the second aspect, after the setting of the non-regression indication, the method further includes: and if the UE returns to the LTE network after the CSFB service is finished, deleting the non-returning indication.

According to any one of the fourth to tenth possible implementation manners of the second aspect, in an eleventh possible implementation manner of the second aspect, the method further includes: and if the UE is determined not to return to the LTE network after the CSFB service is finished, sending an indication message to the MSC/VLR, wherein the indication message is used for indicating the MSC/VLR to delete the second SGs association of the UE on the MSC/VLR.

According to an eleventh possible implementation manner of the second aspect, in a twelfth possible implementation manner of the second aspect, the indication message is a paging rejection message, and the paging rejection message includes a second cause value, where the second cause value is used to indicate separation from the EPS service IMSI.

According to an eleventh possible implementation manner of the second aspect, in a thirteenth possible implementation manner of the second aspect, the indication message is a separation indication message.

According to the third or thirteenth possible implementation manner of the second aspect, in a fourteenth possible implementation manner of the second aspect, the detach indication message includes a detach type, and the detach type is detach from an EPS service IMSI.

According to the eighth or tenth possible implementation manner of the second aspect, in a fifteenth possible implementation manner of the second aspect, the determining that the UE returns to the LTE network after the CSFB service is ended includes: and if receiving the uplink message sent by the UE or receiving a context request message containing the UE identity identifier sent by a new MME, determining that the UE returns to the LTE network after the CSFB service is finished.

According to a fifteenth possible implementation manner of the second aspect, in a sixteenth possible implementation manner of the second aspect, the uplink message is a tracking domain update request message or an extended service request message or a service request message.

In a seventeenth possible implementation manner of the second aspect, according to the second aspect or any of the above possible implementation manners of the second aspect, the deleting the first SGs association includes:

setting a state of the first SGs association to null; or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

In an eighteenth possible implementation manner of the second aspect, according to the second aspect or any of the above possible implementation manners of the second aspect, the CSFB service includes: circuit switched CS voice service; or, CS video services; or, a CS location service; alternatively, the CS supplements the service.

In a third aspect, an embodiment of the present invention provides an MSC/VLR, including:

a determining module, configured to determine that a Circuit Switched Fallback (CSFB) service of a User Equipment (UE) is finished;

and the setting module is used for deleting the first SGs association of the UE on the MSC/VLR.

According to the third aspect, in a first possible implementation manner of the third aspect, the method further includes:

a first sending module, configured to send a detach request message to a mobility management entity MME after the determining module determines that a circuit switched fallback CSFB service of the user equipment UE is ended, where the MME is an MME associated with the first SGs association, the detach request message is used to instruct the MME to delete the first SGs association, and the MSC/VLR is an MSC/VLR associated with the second SGs association.

According to the third aspect, in a second possible implementation manner of the third aspect, the method further includes:

a second sending module, configured to send, after the determining module determines that a Circuit Switched Fallback (CSFB) service of a User Equipment (UE) is ended, a release request message to a Mobility Management Entity (MME), where the MME is associated with the first SGs, and the release request message includes a first cause value, and the first cause value is used to indicate, to the MME, that the CSFB service of the UE is ended.

According to the third aspect, in a third possible implementation manner of the third aspect, the method further includes:

a third sending module, configured to send a CSFB service termination notification message to a mobility management entity MME before the setting module deletes the first SGs association of the UE on the MSC/VLR, where the MME is an MME associated with the first SGs association;

the setting module is specifically configured to delete the first SGs association according to the feedback of the MME.

According to a third possible implementation manner of the third aspect, in a fourth possible implementation manner of the third aspect, the method further includes: a first receiving module, configured to receive a detach indication message sent by a mobility management entity MME after the third sending module sends a CSFB service end notification message to the MME;

the setting module is specifically configured to delete the first SGs association according to the separation indication message.

According to a third possible implementation manner of the third aspect, in a fifth possible implementation manner of the third aspect, the method further includes:

a fourth sending module, configured to send a paging request message to the MME;

a second receiving module, configured to receive an indication message sent by the MME after determining that the UE does not return to a long term evolution LTE network after the CSFB service is ended;

the setting module is specifically configured to delete the first SGs association according to the indication message.

According to a fifth possible implementation manner of the third aspect, in a sixth possible implementation manner of the third aspect, the indication message is a paging rejection message, where the paging rejection message includes a second cause value, and the second cause value is used to indicate separation from an evolved packet system EPS service international mobile subscriber identity IMSI;

the setting module is specifically configured to: deleting the first SGs association according to the second cause value in the paging rejection message.

According to a fifth possible implementation manner of the third aspect, in a seventh possible implementation manner of the third aspect, the indication message is a separation indication message; the setting module is specifically configured to: and deleting the first SGs association according to the separation indication message.

According to a fourth or seventh possible implementation manner of the third aspect, in an eighth possible implementation manner of the third aspect, the detach indication message includes a detach type, and the detach type is detach from the EPS service IMSI.

According to any one possible implementation manner of the fifth to eighth aspects of the third aspect, in a ninth possible implementation manner of the third aspect, the method further includes: and the paging module is used for initiating air interface paging of the UE.

According to any one of the third to ninth possible implementation manners of the third aspect, in a tenth possible implementation manner of the third aspect, the CSFB service end notification message is a release request message, where the release request message includes a first cause value, and the first cause value is used to indicate that the CSFB service of the UE is ended by the MME.

According to the third aspect or any one of the foregoing possible implementation manners of the third aspect, in an eleventh possible implementation manner of the third aspect, the setting module is specifically configured to:

setting a state of the first SGs association to null; or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

According to the third aspect or any one of the foregoing possible implementation manners of the third aspect, in a twelfth possible implementation manner of the third aspect, the CSFB service includes: circuit switched CS voice service; or, CS video services; or, a CS location service; alternatively, the CS supplements the service.

In a fourth aspect, an embodiment of the present invention provides an MME, including:

a first receiving module, configured to receive a Circuit Switched Fallback (CSFB) service end notification message sent by a Mobile Switching Center (MSC)/Visitor Location Register (VLR), where the MSC/VLR is an MSC/VLR associated with a first SGs association of a User Equipment (UE) on the MME, and the CSFB service end notification message is sent by the MSC/VLR when the CSFB service of the UE is determined to be ended;

a first setting module configured to delete the first SGs association.

According to a fourth aspect, in a first possible implementation manner of the fourth aspect, the CSFB service termination notification message is a detach request message, where the detach request message is used to instruct the MME to delete the first SGs association.

According to a fourth aspect, in a second possible implementation manner of the fourth aspect, the CSFB service end notification message is a release request message, where the release request message includes a first cause value, and the first cause value is used to indicate that the CSFB service of the UE ends.

According to the fourth aspect or the second possible implementation manner of the fourth aspect, in a third possible implementation manner of the fourth aspect, the method further includes: a first sending module, configured to send a separation indication message to a mobile switching center MSC/visitor location register VLR after the first receiving module receives a circuit domain fallback CSFB service end notification message sent by the MSC/VLR, where the separation indication message is used to indicate the MSC/VLR to delete a second SGs association of the UE on the MSC/VLR.

According to the fourth aspect or the second possible implementation manner of the fourth aspect, in a fourth possible implementation manner of the fourth aspect, the method further includes: a determining module, configured to determine whether the UE regresses to a long term evolution LTE network after the CSFB service is ended;

the first setting module is specifically configured to: and if the determining module determines that the UE does not return to the LTE network after the CSFB service is finished, deleting the first SGs association.

According to a fourth possible implementation manner of the fourth aspect, in a fifth possible implementation manner of the fourth aspect, the method further includes: a second setting module, configured to set, after the first receiving module receives a circuit switched fallback CSFB service end notification message sent by a mobile switching center MSC/visitor location register VLR, an unreturned indication if the first SGs association exists on the MME, where the unreturned indication is used to indicate that the UE does not return to an LTE network after the CSFB service ends.

According to a fifth possible implementation manner of the fourth aspect, in a sixth possible implementation manner of the fourth aspect, the method further includes:

a third receiving module, configured to receive a paging request message sent by the MSC/VLR;

a paging module, configured to initiate, by the MME, an air interface paging to the UE and start an air interface paging timer, if the UE is in an idle state;

the determining module is specifically configured to determine that the UE does not return to the LTE network after the CSFB service ends, if the air interface paging is overtime and the non-return indication exists.

According to a fifth or sixth possible implementation manner of the fourth aspect, in a seventh possible implementation manner of the fourth aspect, the method further includes: and the starting module is used for starting a regression timer according to the CSFB service end notification message after the first receiving module receives the CSFB service end notification message sent by the mobile switching center MSC/visitor location register VLR.

According to a seventh possible implementation manner of the fourth aspect, in an eighth possible implementation manner of the fourth aspect, the method further includes: a stopping module, configured to stop the regressive timer if a paging request message sent by the MSC/VLR is received, or the determining module determines that the UE regresses to the LTE network after the CSFB service is ended.

According to a seventh or eighth possible implementation manner of the fourth aspect, in a ninth possible implementation manner of the fourth aspect, the determining module is specifically configured to: and if the regression timer is overtime and the non-regression indication exists, determining that the UE does not regress to the LTE network after the CSFB service is finished.

According to any one of the fifth to ninth possible implementation manners of the fourth aspect, in a tenth possible implementation manner of the fourth aspect, the method further includes: and a deleting module, configured to delete the non-regression indication if the determining module determines that the UE regresses to the LTE network after the CSFB service is ended after the non-regression indication is set by the second setting module.

According to any one of the fourth to tenth possible implementation manners of the fourth aspect, in an eleventh possible implementation manner of the fourth aspect, the method further includes: a second sending module, configured to send an indication message to the MSC/VLR if the determining module determines that the UE does not return to the LTE network after the CSFB service is ended, where the indication message is used to indicate the MSC/VLR to delete the second SGs association of the UE on the MSC/VLR.

According to an eleventh possible implementation manner of the fourth aspect, in a twelfth possible implementation manner of the fourth aspect, the indication message is a paging rejection message, and the paging rejection message includes a second cause value, where the second cause value is used to indicate separation from the EPS service IMSI.

According to an eleventh possible implementation manner of the fourth aspect, in a thirteenth possible implementation manner of the fourth aspect, the indication message is a separation indication message.

According to the third or thirteenth possible implementation manner of the fourth aspect, in a fourteenth possible implementation manner of the fourth aspect, the detach indication message includes a detach type, and the detach type is detach from the EPS IMSI.

According to an eighth possible implementation manner or a tenth possible implementation manner of the fourth aspect, in a fifteenth possible implementation manner of the fourth aspect, the determining module is specifically configured to: and if receiving the uplink message sent by the UE or receiving a context request message containing the UE identity identifier sent by a new MME, determining that the UE returns to the LTE network after the CSFB service is finished.

According to a fifteenth possible implementation manner of the fourth aspect, in a sixteenth possible implementation manner of the fourth aspect, the uplink message is a tracking domain update request message or an extended service request message or a service request message.

According to the fourth aspect or any one of the foregoing possible implementation manners of the fourth aspect, in a seventeenth possible implementation manner of the fourth aspect, the first setting module is specifically configured to:

setting a state of the first SGs association to null; or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

In an eighteenth possible implementation manner of the fourth aspect, according to the fourth aspect or any of the above possible implementation manners of the fourth aspect, the CSFB service includes: circuit switched CS voice service; or, CS video services; or, a CS location service; alternatively, the CS supplements the service.

At least one of the technical schemes has the following beneficial effects:

the embodiment of the invention deletes the local SGs association of the UE after determining that the CSFB service of the UE is finished through the MSC/VLR, so that the air interface paging of the UE can be directly started because the SGs association of the UE does not exist locally after the MT call request of the UE is received subsequently, the repeated overtime retransmission is avoided, the delay time of the MT call is reduced, and the success probability of the MT call is greatly increased.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic flowchart of a status updating method according to an embodiment of the present invention;

fig. 2 is a schematic flow chart illustrating a status updating method according to a second embodiment of the present invention;

fig. 3 is a schematic flow chart illustrating a state updating method according to a third embodiment of the present invention;

fig. 4 is a signaling diagram of a state updating method according to a fourth embodiment of the present invention;

fig. 5 is a schematic signaling diagram of a status updating method according to a fifth embodiment of the present invention;

fig. 6 is a schematic signaling diagram of a state updating method according to a sixth embodiment of the present invention;

fig. 7 is a schematic signaling diagram of a state updating method according to a seventh embodiment of the present invention;

fig. 8 is a schematic structural diagram of an MSC/VLR800 according to an eighth embodiment of the present invention;

fig. 9 is a schematic structural diagram of an MME900 according to a ninth embodiment of the present invention;

fig. 10 is a schematic structural diagram of an MSC/VLR100 according to a tenth embodiment of the present invention;

fig. 11 is a schematic structural diagram of an MME200 according to an eleventh embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the embodiment of the present invention, the user equipment ue (user equipment) may be any one of the following, and the user equipment may be static or mobile. User devices may include, but are not limited to: a Station (Station), a Mobile Station (Mobile Station), a Subscriber Unit (Subscriber Unit), a Personal Computer (Personal Computer), a Laptop (Laptop Computer), a Tablet Computer (Tablet Computer), a Netbook (Netbook), a Terminal (Terminal), a Cellular Phone (Cellular Phone), a Handheld device (handset), a cordless Phone (cordless Phone), a Personal Digital Assistant (PDA), a Data Card (Data Card), a USB plug-in device, a Mobile WiFi device (mifis Devices), a smart watch, smart glasses, a Wireless Modem (Modem), a Wireless router, a Wireless local loop (WLL, Wireless LocalLoop) Station, and the like. The user equipment may be distributed throughout the wireless network.

The LTE Network described in this specification is an Evolved UMTS terrestrial Radio Access Network (hereinafter, referred to as Evolved UMTS terrestrial Radio Access Network, abbreviated as E-UTRAN), where UMTS chinese is referred to as Universal Mobile telecommunications System (UMTS Mobile telecommunications System), and second Generation (2 nd Generation, 2G) Network is a GSM/EDGE Radio Access Network (hereinafter, referred to as GSM/EDGE Access Network, abbreviated as GERAN), where GSM chinese is referred to as Global System for Mobile communications (Global System of Mobile communications, Enhanced Data Rate GSM Evolution (EDGE) chinese is referred to as Enhanced Data Rate for GSM Evolution), and third Generation (3 rd Generation, 3G) Network is an UTRAN Network. A Public Land Mobile Network (PLMN) of the LTE network provides only PS domain services, and the 2G/3G network includes both a PLMN providing CS domain services and a PLMN providing PS domain services.

In the embodiment of the present invention, a Mobile Switching Center (MSC)/Visitor Location Register (VLR) is generally combined as the same network element, which is called as MSC/VLR or abbreviated as VLR. The MSC/VLR and the MME interact through an SGs interface, and accordingly, a message interacted between the MSC/VLR and the MME may also be referred to as an SGs message, for example, a detach request message may also be referred to as an SGs detach request message.

In the embodiment of the present invention, a circuit switched fallback CSFB service, specifically a CS service executed after a UE residing in an LTE network initiates a CSFB procedure to fall back to a 2G/3G network because the UE needs to execute a circuit switched CS service, where the CSFB service is divided into an uplink CSFB service and a downlink CSFB service, and the CSFB service includes but is not limited to: CS voice service; or, CS video services; or, a CS location service; alternatively, the CS supplements the service. For convenience of description, the embodiment of the present invention is described by taking a CS voice service as an example.

Fig. 1 is a flowchart illustrating a status updating method according to an embodiment of the present invention. As shown in fig. 1, the method includes:

101. the MSC/VLR determines that the CSFB service of the UE is finished.

After a UE successfully co-registered in an LTE network initiates a CSFB procedure to fall back to a 2G/3G network CS domain due to the need to perform a CSFB service (e.g., voice call), a required CS signaling connection is established, and then a required CS service is performed. When the CS service is finished, the MSC/VLR receives a service disconnection instruction from the UE or a service release instruction from the opposite terminal MSC/VLR, and the MSC/VLR determines that the CSFB service is finished according to the received service disconnection instruction or service release instruction.

102. And deleting the first SGs association of the UE on the MSC/VLR.

Before 101, the UE has successfully co-registered with the PS domain of EPC and the CS domain of 2G/3G network. After the combined registration is successful, an SGs association is established for the UE between the mobility management entity MME in the registered PS domain and the MSC/VLR in the 2G/3G network, for example, the MME and the MSC/VLR both locally store an SGs association for the UE, that is, the state of the SGs association is set to an active state (SGs-ASSOCIATED or active), and the active state may also be understood as a valid state (valid). For convenience of description, in this embodiment, the SGs association on the MSC/VLR is referred to as a first SGs association, and the SGs association on the MME is referred to as a second SGs association. Accordingly, 102 may include:

setting a state associated with the first SGs to Null (Null); or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

Specifically, a flag bit (flag), which may be specifically referred to as an association flag bit, may be used on the MSC/VLR to indicate a state of association of the first SGs of a UE, where different values of the association flag bit indicate different states of association of the first SGs, for example, when the association flag bit is 1, the state of association of the first SGs of the UE is an active state or a legal state, and when the association flag bit is 0, the state of association of the first SGs of the UE is an inactive state or an illegal state. Deleting the context information associated with the first SGs includes deleting an association flag on the MSC/VLR for indicating a state of the first SGs association of the UE.

Correspondingly, after deleting the first SGs association of the UE on the MSC/VLR, the MSC/VLR does not have the SGs association of the UE.

In an optional embodiment of the present invention, after 101, further comprising:

the MSC/VLR sends a separation request message to an MME, wherein the MME is associated with the first SGs association, the separation request message is used for indicating the MME to delete a second SGs association of the UE on the MME, and the MSC/VLR is associated with the second SGs association.

Generally, there is only one MME associated with the SGs association of one UE that successfully performs joint registration, and the MMEs associated with the SGs associations of different UEs that successfully perform joint registration may be the same or different.

Further, after the MSC/VLR sends the detach request message to the mobility management entity MME, the method further includes: and receiving a separation acceptance message sent by the MME.

In yet another optional embodiment of the present invention, after 101, further comprising:

the MSC/VLR sends a release request message to an MME, the MME associates the associated MME with the first SGs, the release request message comprises a first reason value, and the first reason value is used for indicating the MME that the CSFB service of the UE is ended.

Correspondingly, after receiving the release request message, the MME may delete the second SGs association of the UE on the MME, so that even if the MSC/VLR initiates an SGs interface paging to the MME, the MME directly rejects the SGs interface paging of the MSC/VLR because the second SGs association of the UE does not exist locally, thereby prompting the MSC/VLR to directly initiate an air interface paging of the UE.

Generally, after receiving the release request message, the MME does not need to reply a message to the MSC/VLR. It should be noted that, in this embodiment, the time sequence between the MSC/VLR sending the release request message to the MME and 102 may be arbitrary.

The embodiment of the invention deletes the local SGs association of the UE after determining that the CSFB service of the UE is finished through the MSC/VLR, so that when the MT call request of the UE is subsequently received, the air interface paging of the UE can be directly initiated because the SGs association of the UE does not exist locally, the repeated overtime retransmission of an MME (mobility management entity) initiating the SGs association is avoided, the delay time of the MT call is reduced, and the success probability of the MT call is greatly increased.

Fig. 2 is a flowchart illustrating a status updating method according to a second embodiment of the present invention. As shown in fig. 2, the method includes:

201. the MSC/VLR determines that the CSFB service of the UE is finished.

The specific implementation of 201 refers to 101 in the first embodiment.

202. And the MSC/VLR sends a CSFB service ending notification message to an MME, wherein the MME is the MME associated with the first SGs of the UE on the MSC/VLR.

Optionally, the CSFB service end notification message is a release request message, where the release request message includes a first cause value, and the first cause value is used to indicate that the CSFB service of the UE is ended by the MME. Generally, there is only one MME associated with the SGs association of one UE successfully performing the joint registration on the MSC/VLR, and the MMEs associated with the SGs associations of different UEs successfully performing the joint registration may be the same or different.

203. And deleting the first SGs association according to the feedback of the MME.

Typically, before 201, the UE successfully registers in the PS domain of EPC and the CS domain of 2G/3G network jointly. After the combined registration is successful, an SGs association is established for the UE between the mobility management entity MME in the registered PS domain and the MSC/VLR in the 2G/3G network, for example, the MME and the MSC/VLR both locally store an SGs association for the UE, that is, the state of the SGs association is set to an active state (SGs-ASSOCIATED or active), and the active state may also be understood as a valid state (valid). For convenience of description, in this embodiment, the SGs association on the MSC/VLR is referred to as a first SGs association, and the SGs association on the MME is referred to as a second SGs association. Accordingly, 203 may include:

setting a state associated with the first SGs to Null (Null); or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

Specifically, an association flag may be used on the MSC/VLR to indicate that a first SGs association of a UE is associated, and different values of the association flag indicate different states of the first SGs association, for example, when the association flag is 1, the state of the first SGs association of the UE is an active state, and when the association flag is 0, the state of the first SGs association of the UE is inactive or illegal. Correspondingly, deleting the context information associated with the first SGs includes deleting an association flag on the MSC/VLR for indicating the state of the first SGs association of the UE.

In particular, the feedback of the MME may take various forms.

In an optional embodiment of the present invention, the feedback is a separation indication message, that is, after 202, the method further includes:

receiving a detachment indication message sent by the MME;

accordingly, 203, comprises:

In yet another optional embodiment of the present invention, the feedback is an indication message sent by the MME after determining that the UE does not return to a long term evolution LTE network after the CSFB service ends. Accordingly, after 202, further comprising:

sending a paging request message to the MME;

203, comprising:

and deleting the first SGs association according to the indication message.

Generally, when receiving the MT call request of the UE, the MSC/VLR first sends a paging request message to the MME and starts an SGs paging timer if the state associated with the first SGs of the UE on the MSC/VLR is an active state.

Further, this embodiment further includes:

and initiating air interface paging to the UE.

Usually, in a 2G network, the MSC/VLR initiates an air interface paging to the UE through an a interface; in the 3G network, MSC/VLR initiates the air interface paging to the UE through Iu interface.

Optionally, the indication message is a paging rejection message, where the paging rejection message includes a second cause value, and the second cause value is used to indicate separation from an Evolved Packet System (EPS) service International Mobile Subscriber Identity (IMSI) for International Mobile Subscriber Identity (IMSI) discovery;

Usually, the MSC/VLR also starts the SGs paging timer when sending the paging request message to the MME, and further, the MSC/VLR also stops the previously started SGs paging timer when receiving the paging reject message containing the second cause value.

Optionally, the indication message is a separation indication message; deleting the first SGs association according to the indication message, including:

Further, in each of the above optional embodiments, the detach indication message includes a detach type, where the detach type is detached from the EPS service IMSI.

Further, in each of the above optional embodiments, the method further includes:

after receiving the detach indication message, the MSC/VLR sends a detach confirm message to the MME.

In the embodiment of the invention, after determining that the CSFB service of the UE is finished, the MSC/VLR sends the CSFB service finishing notification message to the MME associated with the SGs of the UE, and deletes the local SGs association of the UE after receiving the feedback of the MME, so that when an MT call request of the UE is subsequently received, empty paging of the UE can be directly initiated due to the local absence of the SGs association of the UE, multiple overtime retransmissions of the MME which initiates the SGs association are avoided, the delay time of MT call is reduced, and the success probability of MT call is greatly increased.

Fig. 3 is a flowchart illustrating a state updating method according to a third embodiment of the present invention. As shown in fig. 3, the method includes:

301. an MME receives a CSFB service ending notification message sent by an MSC/VLR, wherein the MSC/VLR is the MSC/VLR associated with the first SGs of UE on the MME, and the CSFB service ending notification message is sent by the MSC/VLR when the CSFB service of the UE is determined to be ended.

Usually, the MSC/VLR interacts with the MME through the SGs interface. Generally, there is only one MSC/VLR associated with the SGs association of one UE successfully co-registered on the MME, and the MSC/VLRs associated with the SGs associations of different UEs successfully co-registered may be the same or different.

When a UE successfully co-registered in an LTE network needs to perform a CSFB Service (e.g., a voice call), a Request message, e.g., an Extended Service Request (Extended Service Request) message, is sent to the registered MME. The MME is aware that the UE initiated the CSFB service. After the CSFB service is finished in the CS domain of the 2G/3G network, the MSC/VLR sends a CSFB service finishing notification message to the MME so that the MME knows that the CSFB service is finished.

Wherein the CSFB service may include, but is not limited to: CS voice service; or, CS video services; or, a CS location service; alternatively, the CS supplements the service.

302. Deleting the first SGs association.

Before 301, the UE has successfully co-registered with the PS domain of the EPC and the CS domain of the 2G/3G network. After the combined registration is successful, an SGs association is established for the UE between the mobility management entity MME in the registered PS domain and the MSC/VLR in the 2G/3G network, for example, both the MME and the MSC/VLR locally store an SGs association for the UE, that is, the SGs association state is set to an active state (SGs-ASSOCIATED or active), and the active state may also be understood as a valid state (valid). For convenience of description, in this embodiment, the SGs association on the MME is referred to as a first SGs association, and the SGs association on the MSC/VLR is referred to as a second SGs association. Accordingly, 302 may include:

setting a state associated with the first SGs to Null (Null); or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

Specifically, an association flag bit may be used on the MME to indicate a state of a first SGs association of a UE, where different values of the association flag bit indicate different states of the first SGs association, for example, when the association flag bit is 1, the state of the first SGs association of the UE is an active state, and when the association flag bit is 0, the state of the first SGs association of the UE is inactive or illegal. Accordingly, deleting the first SGs association of the UE on the MME includes deleting an association flag bit used for indicating a state of the first SGs association of the UE on the MME.

Correspondingly, after deleting the first SGs association of the UE on the MME, the SGs association of the UE does not exist on the MME.

In an optional embodiment of the present invention, the CSFB service termination notification message is a detach request message, and the detach request message is used to instruct the MME to delete the first SGs association.

Further, after 301, the method further includes:

and sending a separation acceptance message to the MSC/VLR.

In yet another optional embodiment of the present invention, the CSFB service end notification message is a release request message, where the release request message includes a first cause value, and the first cause value is used to indicate that the CSFB service of the UE ends.

In yet another optional embodiment of the present invention, the CSFB service end notification message is a release request message, where the release request message includes a first cause value, and the first cause value is used to indicate that the CSFB service of the UE ends. And, after 301, further comprising:

Further, after the separation indication message is sent, a separation confirmation message returned by the MSC/VLR may also be received.

Specifically, the MME initiates an explicit SGs EPS detach procedure to the MSC/VLR, that is, the detach indication message includes a detach type for indicating detach from the EPS service IMSI, and further, the MME may count the number of times of CSFB call termination according to a CSFB service termination notification sent by the MSC/VLR.

In yet another optional embodiment of the present invention, the CSFB service end notification message is a release request message, where the release request message includes a first cause value, and the first cause value is used to indicate that the CSFB service of the UE ends. And, before 302, further comprising:

and determining that the UE does not return to a Long Term Evolution (LTE) network after the CSFB service is finished.

Optionally, after 301, further comprising:

Wherein the first SGs association exists on the MME, that is, a state of the SGs association of the UE on the MME is an active state. The expression of the non-regression indication may be a bit (bit), for example, "1" indicates that the UE does not regress to the LTE network after the CSFB service is ended, and "0" indicates that the UE regresses to the LTE network after the CSFB service is ended; the non-regression indication may also be represented by a status bit, for example, "True" indicates that the UE does not return to the LTE network after the CSFB service is ended, and "False" indicates that the UE returns to the LTE network after the CSFB service is ended. The setting of the non-return indication may be to set the bit to a state indicating that the UE does not return to the LTE network after the CSFB service is ended, or to indicate that the UE does not return to the LTE network after the CSFB service is ended by using the presence of the bit, and accordingly, if the bit is deleted, the UE is considered to return to the LTE network after the CSFB service is ended. Those skilled in the art can implement the unreturned indication by means of a value of a cell, or whether a specific cell exists, and the like, which is not limited in the embodiment of the present invention.

Accordingly, after the setting of the non-regression indication, the method further comprises:

and if the UE returns to the LTE network after the CSFB service is finished, deleting the non-return indication.

Specifically, the deleting of the non-regression indication is to set the non-regression indication to a state indicating that the UE has regressed to the LTE network after the CSFB service is finished, for example, a corresponding bit is set to "0" or "False", or the bit is deleted, which is not limited herein.

Further, this embodiment further includes:

receiving a paging request message sent by the MSC/VLR;

if the UE is in an idle state, the MME initiates an air interface paging to the UE, and starts an air interface paging timer (e.g., T3413 timer);

correspondingly, the determining that the UE does not return to the long term evolution LTE network after the CSFB service is ended includes:

Wherein, the existence of the non-regression indication may also be understood as that the non-regression indication is not deleted.

Typically, the MSC/VLR will send a paging request message to the MME upon receiving the MT call request of the UE.

Further, after 301, the method further includes:

Specifically, the regression timer is stopped when a specific event occurs. Correspondingly, this embodiment further includes:

Further, in a scenario where a regression timer is started, the determining that the UE does not regress to the long term evolution LTE network after the CSFB service is ended includes:

and if the regression timer is overtime and the non-regression indication exists, determining that the UE does not regress to the LTE network after the CSFB service is finished.

In the above embodiment, further, the method further includes:

and if the UE is determined not to return to the LTE network after the CSFB service is finished, sending an indication message to the MSC/VLR, wherein the indication message is used for indicating the MSC/VLR to delete the second SGs association of the UE on the MSC/VLR.

Optionally, the indication message is a paging rejection message, where the paging rejection message includes a second cause value, and the second cause value is used to indicate separation from the EPS service IMSI.

Optionally, the indication message is a separation indication message; after the sending the indication message to the MSC/VLR, the method further comprises: and receiving a separation confirmation message sent by the MSC/VLR. Specifically, the MME initiates an explicit sgeps detach procedure to the MSC/VLR, that is, the detach indication message includes a detach type for indicating detach from the EPS service IMSI.

In the above embodiment, there may be a plurality of ways to determine whether the UE returns to the LTE network after the CSFB service is ended. For example, the determining that the UE returns to the LTE network after the CSFB service is ended includes:

and if receiving the uplink message sent by the UE or receiving a context request message containing the UE identity identifier sent by a new MME, determining that the UE returns to the LTE network after the CSFB service is finished.

The condition of receiving the uplink message is mainly suitable for the UE to return to a service area of a previously registered MME; the case of receiving the context request message sent by the new MME is mainly applicable to the UE returning to the service area of other MME, i.e. the service area of MME that is not registered before. After the UE falls back to the 2G/3G network, if location update is performed in the 2G/3G network or a PS service is suspended, the UE needs to send an uplink message to the MME when returning to the LTE network, and typically, a location update procedure needs to be initiated to re-register to the LTE network and recover the suspended PS service. If the UE returns to the MME registered before, the uplink message is directly sent to the registered MME, and the registered MME learns that the UE returns to the LTE network according to the uplink message; if returning to other MME (called new MME), the uplink message is sent to the new MME, then the new MME finds the MME registered before the UE according to the identity information reported by the UE, and sends a context request message containing the identity of the UE to the MME registered before, and the registered MME knows that the UE returns to the LTE network according to the context request message. It should be noted that the uplink message may be a Tracking Area update (Tracking Area Updating) Request message, an Extended Service Request (Extended Service Request) message, or a Service Request (Service Request) message.

In the embodiment of the invention, the MME deletes the SGs association of the local UE after receiving the CSFB service end notification message of the UE sent by the MSC/VLR, so that even if the MSC/VLR initiates the SGs interface paging to the MME, the MME can directly refuse the SGs interface paging of the MSC/VLR because the SGs association of the UE does not exist locally, the MSC/VLR directly initiates the air interface paging of the UE, thereby avoiding multiple times of overtime retransmission initiated to the MME, reducing the delay time of MT calling and greatly increasing the success probability of MT calling.

Fig. 4 is a signaling flowchart of a status updating method according to a fourth embodiment of the present invention. As shown in fig. 4, the method includes:

401. and the UE with successful joint registration initiates a CSFB procedure at the E-UTRAN.

Before 401, the UE needs to initiate a joint attach procedure or a joint location update procedure, and successfully perform joint registration with the CS domain of the 2G/3G network in the PS domain of the EPC network. The CSFB procedure includes UE-initiated mo (mobile ordered) CSFB procedure and network-initiated MT CSFB procedure.

After the UE is successfully jointly registered, an SGs association is established for the UE between a mobility management entity MME in the registered PS domain and an MSC/VLR in the 2G/3G network, for example, the MME and the MSC/VLR both locally store an SGs association for the UE, that is, the state of the SGs association is set to an active state (SGs-ASSOCIATED or active), and the active state may also be understood as a valid state (valid). Generally, there is only one MME and one MSC/VLR associated with the SGs association of one UE that succeeds in joint registration, and the MME and the MSC/VLR associated with the SGs association of different UEs that succeed in joint registration may be the same or different. For convenience of description, in this embodiment, the SGs association on the MSC/VLR is referred to as a first SGs association, and the SGs association on the MME is referred to as a second SGs association.

402. The MSC/VLR determines that the CSFB service is finished.

In 401, after initiating a CSFB procedure to fall back to a CS domain of a 2G/3G network, the UE needs to establish a required CS signaling connection and then perform a required CS service. When the CS service is finished, the MSC/VLR receives a service disconnection instruction from the UE or a service release instruction from the opposite terminal MSC/VLR, and the MSC/VLR determines that the CSFB service is finished according to the received service disconnection instruction or service release instruction.

Further, the MSC/VLR may count the number of times the CSFB service of the UE ends.

403a, MSC/VLR deletes the first SGs association of the UE.

Optionally, the deleting the first SGs association of the UE may include:

setting a state of the first SGs association to null; or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

403b, MSC/VLR sends a detach request message to MME.

Optionally, after sending the detach request message, the MME starts a detach timer for monitoring whether the detach procedure is successfully executed.

If the separation receiving message replied by the MME is not received when the timer is overtime, the separation request message is retransmitted, and the separation timer is restarted.

404a, the MME replies a separation acceptance message to the MSC/VLR.

The MSC/VLR stops 403b the detach timer started after receiving the detach accept message.

404b, the MME deletes the second SGs association of the UE.

Optionally, the deleting the second SGs association of the UE may include:

setting a state of the second SGs association to null; or,

deleting context information associated with the second SGs; or,

setting a state of the second SGs association to invalid; or,

setting the state associated with the second SGs to be illegal; or,

and if the state associated with the second SGs is an activated state, setting the state associated with the second SGs to be a deactivated state.

Specifically, a flag bit (flag), which may be specifically referred to as an association flag bit, may be used on the MME to indicate a state of the second SGs association of the UE, where different values of the association flag bit indicate different states of the second SGs association, for example, when the association flag bit is 1, the state of the second SGs association of the UE is an active state or a legal state, and when the association flag bit is 0, the state of the second SGs association of the UE is an inactive state or an illegal state. Deleting the context information associated with the second SGs comprises deleting an association flag bit used for indicating the state of the second SGs association of the UE on the MME.

Correspondingly, after deleting the second SGs association of the UE, the MME does not have the SGs association of the UE.

After the MME deletes the second SGs association of the UE, if a paging request of the UE sent by the MSC/VLR is received, the MME directly rejects the paging request, and a reason value is contained in a paging rejection message and used for indicating separation from the EPS service IMSI.

After the MME deletes the second SGs association of the UE, if a location update request sent by the UE returning to the LTE network after the CSFB service is completed is received, the MME initiates a location update request to the MSC/VLR, thereby implementing re-registration of the UE to the CS domain.

It should be noted that there is no time sequence restriction between the above 404a and 404b, that is, the MME may execute 404a first and then 404 b; or, 404b is executed first and then 404a is executed; alternatively, 404a and 404b are performed simultaneously.

Further, the MME may count the number of times of CSFB service termination of the UE according to the detach request message sent by the MSC/VLR.

The separation request message and the separation acceptance message are new messages. Optionally, the detach request message in 403b may also be replaced with an existing release request message, but a new cause value needs to be added to the existing release request message to indicate that the CSFB service of the UE is ended by the MME. If the MSC/VLR in 403a sends the existing release request message, the MME does not need to reply any message to the MSC/VLR, i.e. does not need to execute 404 a.

The embodiment of the invention deletes the local SGs association of the UE after determining that the CSFB service of the UE is finished through the MSC/VLR, so that when an MT call request of the UE is subsequently received, the MSC/VLR directly initiates the air interface paging of the UE according to the fact that the SGs association of the UE does not exist locally, multiple overtime retransmission of an MME initiating the SGs association is avoided, the delay time of the MT call is reduced, and the success probability of the MT call is greatly increased; further, the embodiment of the present invention sends the separation indication message to the MME associated with the SGs association of the UE through the MSC/VLR, so that the MME synchronously deletes the SGs association of the UE, thereby ensuring that the UE re-registers to the CS domain if the UE reverts to the LTE network after the CSFB service is finished, and ensuring the successful implementation of the subsequent MT CS service.

Fig. 5 is a signaling flowchart of a status updating method according to a fifth embodiment of the present invention. As shown in fig. 5, the method includes:

501. and the UE with successful joint registration initiates a CSFB procedure at the E-UTRAN.

502. The MSC/VLR determines that the CSFB service is finished.

The specific implementation of 501-502 is described in 401-402, and will not be described herein.

503. If the first SGs association of the UE exists, the MSC/VLR sends a CSFB service ending notification message to the MME.

For convenience of description, in this embodiment, the SGs association on the MSC/VLR is referred to as a first SGs association, and the SGs association on the MME is referred to as a second SGs association.

503 refer to the related contents of 202 in the second embodiment of the present invention.

504a, the MME deletes the second SGs association of the UE.

504b, MME sends separation indication message to MSC/VLR.

Generally, when the MME learns that the CSFB service is finished, if the second SGs association of the UE exists locally, the MME initiates an explicit SGs EPS detach procedure, that is, sends a detach indication message to the MSC/VLR. Further, the MME may count the number of times of CSFB service termination of the UE according to the CSFB service termination notification message sent by the MSC/VLR. The specific implementation of 504a, 504b refers to the related content 302 in the third embodiment of the present invention.

505a, MSC/VLR replies the separation confirmation message to MME.

505b, the MSC/VLR deletes the first SGs association of the UE.

505a and 505b refer to the related contents of 203 in the second embodiment of the present invention.

It should be noted that the CSFB service termination notification message may be a newly added message, or may reuse an existing release request message, and if the existing release request message is reused, a new cause value needs to be added to the release request message.

The embodiment of the invention sends a CSFB service ending notification message to an MME which is hung by an SGs association of UE after the CSFB service of the UE is determined to end through MSC/VLR, the MME deletes the SGs association of the local UE after receiving the CSFB service ending notification message and sends a separation indication message to the MSC/VLR, and the MSC/VLR deletes the SGs association of the local UE after receiving the separation indication message of the MME, so that the MSC/VLR directly sends an empty paging to the UE according to the SGs association which does not exist in the local when the MSC/VLR receives an MT call request of the UE in the subsequent process, even if the MSC/VLR sends the SGs interface paging to the MME, the MSC/VLR directly rejects the SGs interface paging of the MSC/VLR according to the SGs association which does not exist in the local, avoids the MSC/VLR from sending to the MME which is associated with the SGs for multiple times of overtime retransmission, and reduces the delay time of the, the probability of MT call success is greatly increased.

Fig. 6 is a signaling flowchart of a status updating method according to a sixth embodiment of the present invention. As shown in fig. 6, the method includes:

601. and the UE with successful joint registration initiates a CSFB procedure at the E-UTRAN.

602. The MSC/VLR determines that the CSFB service is finished.

603. If the first SGs association of the UE exists, the MSC/VLR sends a CSFB service ending notification message to the MME.

The specific implementation of 601-603 refers to 501-503 in the fifth embodiment of the present invention, and details are not repeated here.

604. And if the second SGs association of the UE exists, the MME sets a non-regression indication.

Accordingly, if the MME determines that the UE regresses to E-UTRAN, the non-regressive indication is cleared. 604 refer to 302 of the third embodiment of the present invention.

Further, the MME may count the number of times of CSFB service termination of the UE according to the CSFB service termination notification message.

605. When a new MT call arrives, the MSC/VLR sends a paging request message to the MME.

At the same time, MSC/VLR starts SGs paging timer.

606. If the UE is in idle state, the MME performs 607.

607. The MME sends a paging request to the UE and starts an air paging timer (e.g., T3413 timer).

608. And after the CSFB service is finished, if the UE returns to the E-UTRAN, replying a paging response.

The paging response includes, but is not limited to, a Tracking Area update Request (Tracking Area update Request) message, an Extended Service Request (Extended Service Request) message, or a general Service Request (Service Request) message.

609. If the MME receives the paging response of the UE, the air interface paging timer is stopped and the non-regression indication is cleared.

610. If the air interface paging timer is overtime and the non-regression indication exists, deleting the second SGs association of the UE, clearing the non-regression indication, and sending a paging rejection message to the MSC/VLR.

The paging rejection message contains a cause value separated from the EPS service IMSI.

605-610 refer to the related contents of 302 in the third embodiment of the present invention.

611a, the MSC/VLR deletes the second SGs association for the UE.

611b, MSC/VLR initiates paging from the A/Iu interface to the UE.

At the same time, the MSC/VLR stops the SGs paging timer started in 605. 611a, 611b refer to the related contents of 203 in the second embodiment of the present invention.

It should be noted that: the CSFB service termination notification message may be a newly added message, or may reuse an existing release request message, and if the existing release request message is reused, a new cause value needs to be added to the release request message. Specifically, the MME can judge whether the UE regresses the E-UTRAN or not by receiving the information that the UE regresses the E-UTRAN, wherein the information that the UE regresses the E-UTRAN can comprise (1) uplink information sent after the UE regresses to the original MME, namely the MME registered before initiating the CSFB process, such as Tracking Area Update (TAU) request information or extended service request information or service request information and the like; (2) and after the UE returns to the new MME, the new MME sends a context request message.

In the embodiment of the invention, after determining that the CSFB service of the UE is finished, the MSC/VLR sends a CSFB service finishing notification message to an MME associated with the SGs association of the UE, the MME sets an unreregressive indication for identifying that the UE does not regress to an LTE network according to the existing SGs association of the UE, the MME initiates a paging request to the UE when receiving the paging request message sent by the MSC/VLR, if the paging is overtime and the unreregressive indication exists, the MME deletes the SGs association of the local UE and clears the unreregressive indication, and sends a paging rejection message to the MSC/VLR, the MSC/VLR deletes the SGs association of the local UE after receiving the paging rejection message of the MME, so that when the MSC/VLR subsequently receives the MT call request of the UE, the MSC/VLR directly sends an empty paging to the UE according to the SGs association of the local UE, even if the MSC/VLR initiates the SGs interface paging to the, the MME can also directly reject the SGs interface paging of the MSC/VLR according to the local absence of the SGs association of the UE, so that the phenomenon that the MSC/VLR initiates repeated overtime retransmission to the MME associated with the SGs is avoided, the delay time of MT calling is reduced, the success probability of MT calling is greatly increased, and the MME can judge whether the UE returns to the LTE network according to the non-return indication.

Fig. 7 is a signaling flowchart of a status updating method according to a seventh embodiment of the present invention. As shown in fig. 7, the method includes:

701. and the UE with successful joint registration initiates a CSFB procedure at the E-UTRAN.

702. The MSC/VLR determines that the CSFB service is finished.

703. If the first SGs association of the UE exists, the MSC/VLR sends a CSFB service ending notification message to the MME.

For specific implementation of 701-703, reference is made to 501-503 in the fifth embodiment of the present invention, and details are not described here.

704. And if the second SGs association of the UE exists, the MME sets a non-regression indication and starts a regression timer.

The regression timer is used to detect whether the MME receives the paging request message after learning that the CSFB service is finished. Typically, if the MME determines that the UE returns to E-UTRAN, the non-return indication is cleared and the return timer is stopped. Further, the MME may count the number of times of CSFB service termination of the UE according to the CSFB service termination notification message. 704 refer to 302 of the third embodiment of the present invention.

705. When there is a new MT call, MSC/VLR sends a paging request message to MME.

At the same time, MSC/VLR starts SGs paging timer.

706. The MME stops the regression timer, and if the UE is in an idle state, the MME performs 707.

707. The MME sends a paging request to the UE and starts an air paging timer (e.g., T3413 timer).

708. And after the CSFB service is finished, if the UE returns to the E-UTRAN, replying a paging response.

709. If the MME receives the paging response of the UE, the air interface paging timer is stopped and the non-regression indication is cleared.

710. If the air interface paging timer is overtime or the regression timer is overtime and the non-regression indication exists, the MME sends a separation indication message to the MSC/VLR and deletes the second SGs association of the UE.

That is, when the T3413 timer times out or the regressive timer times out, and there is the non-regressive indication, the MME initiates an explicit SGs EPS detach procedure.

706-710 refer to the related contents 302 in the third embodiment of the present invention.

711a, MSC/VLR replies the detachment acceptance message to MME.

711b, the MSC/VLR deletes the first SGs association for the UE and initiates paging to the UE from the A/Iu interface.

Meanwhile, if the SGs paging timer started in 705 is still running, the MSC/VLR stops the SGs paging timer. 711a and 711b refer to the related contents of 203 in the second embodiment of the present invention.

In the embodiment of the invention, after determining that the CSFB service of the UE is finished, the MSC/VLR sends a CSFB service finish notification message to an MME associated with the SGs association of the UE, the MME sets an unreregressive indication and a regressive timer for identifying that the UE does not regress an LTE network according to the SGs association of the UE locally, the MME stops the regressive timer and sends a paging request to the UE when receiving the paging request message sent by the MSC/VLR, if the paging is carried out or the regressive timer is overtime and has the unreregressive indication, the MME deletes the SGs association of the local UE and clears the unreregressive indication, the MME sends a paging rejection message to the MSC/VLR, the MSC/VLR deletes the SGs association of the local UE after receiving the paging rejection message of the MME, so that the MSC/VLR directly sends a paging empty port to the UE according to the SGs association of the UE locally absent when subsequently receiving the MT call request of the UE, even if the MSC/VLR initiates the SGs interface paging to the MME, the MME can directly refuse the SGs interface paging of the MSC/VLR according to the fact that the SGs association of the UE does not exist locally, multiple times of overtime retransmission of the MME initiated by the MSC/VLR to the SGs association are avoided, the delay time of the MT call is reduced, the success probability of the MT call is greatly increased, and the MME can judge whether the UE returns to the LTE network according to the non-return indication.

Fig. 8 is a schematic structural diagram of an MSC/VLR800 according to an eighth embodiment of the present invention. As shown in fig. 8, the MSC/VLR800 includes:

a determining module 81, configured to determine that a CSFB service of the UE ends;

a setting module 82, configured to delete the first SGs association of the UE on the MSC/VLR.

In an alternative embodiment of the present invention, the MSC/VLR800 further comprises:

a first sending module, configured to send, after the determining module determines that the CSFB service of the UE is finished, a detach request message to an MME, where the MME is an MME associated with the first SGs association, and the detach request message is used to instruct the MME to delete the second SGs association of the UE on the MME.

In yet another alternative embodiment of the present invention, the MSC/VLR800 further comprises:

a second sending module, configured to send a release request message to an MME after the determining module determines that the CSFB service of the UE ends, where the MME is an MME associated with the first SGs, and the release request message includes a first cause value, and the first cause value is used to indicate that the CSFB service of the UE ends by the MME.

a third sending module, configured to send a CSFB service termination notification message to an MME before the setting module deletes the first SGs association, where the MME is an MME associated with the first SGs association;

correspondingly, the setting module is specifically configured to delete the first SGs association according to the feedback of the MME.

Optionally, the MSC/VLR800 further comprises:

a first receiving module, configured to receive a detach indication message sent by an MME after the third sending module sends a CSFB service end notification message to the MME;

Optionally, the MSC/VLR800 further comprises:

Further, the indication message is a paging rejection message, the paging rejection message includes a second cause value, and the second cause value is used for indicating separation from the EPS IMSI;

Optionally, the indication message is a separation indication message; the setting module is specifically configured to: and deleting the first SGs association according to the separation indication message.

Optionally, the detach indication message includes a detach type, where the detach type is detached from the EPS service IMSI.

Optionally, the MSC/VLR800 further comprises:

a fifth sending module, configured to send a detach confirmation message to the MME after the first receiving module or the second receiving module receives the detach indication message.

Further, the MSC/VLR800 also includes:

and the paging module is used for initiating air interface paging of the UE.

Further, the CSFB service end notification message is a release request message, where the release request message includes a first cause value, and the first cause value is used to indicate that the CSFB service of the UE is ended by the MME.

Further, the setting module is specifically configured to:

setting a state of the first SGs association to null; or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

Optionally, the CSFB service includes: circuit switched CS voice service; or, CS video services; or, a CS location service; alternatively, the CS supplements the service.

Further, the MSC/VLR800 also includes:

and the counting module is used for counting the times of the CSFB service end of the UE after the determining module determines that the CSFB service of the UE is ended.

The MSC/VLR of this embodiment may be configured to implement the technical solution of the first or second embodiment of the method, and the implementation principle and technical effect are similar, which are not described herein again.

The embodiment of the invention deletes the local SGs association of the UE after determining that the CSFB service of the UE is finished through the MSC/VLR, thereby directly initiating the air interface paging of the UE when the MT call request of the UE is subsequently received because the SGs association of the UE does not exist locally, avoiding the repeated overtime retransmission of the MME initiating the SGs association, reducing the delay time of the MT call and greatly increasing the success probability of the MT call.

Fig. 9 is a schematic structural diagram of an MME900 according to a ninth embodiment of the present invention. As shown in fig. 9, the MME900 includes:

a first receiving module 91, configured to receive a CSFB service termination notification message sent by an MSC/VLR, where the MSC/VLR is an MSC/VLR associated with a first SGs association of a UE on an MME900, and the CSFB service termination notification message is sent by the MSC/VLR when it is determined that the CSFB service of the UE is terminated;

a first setting module 92 configured to delete the first SGs association.

In an optional embodiment of the present invention, the CSFB service end notification message is a detach request message.

In yet another optional embodiment of the present invention, the CSFB service end notification message is a release request message, where the release request message includes a first cause value, and the first cause value is used to indicate that the CSFB service of the UE is ended.

Optionally, the MME900 further includes:

a first sending module, configured to send a separation indication message to the MSC/VLR after the first receiving module receives a CSFB service termination notification message sent by the MSC/VLR, where the separation indication message is used to indicate the MSC/VLR to delete a second SGs association of the UE on the MSC/VLR;

and the second receiving module is used for receiving the separation confirmation message returned by the MSC/VLR.

Further, the MME900 further includes:

a determining module, configured to determine whether the UE regresses to a long term evolution LTE network after the CSFB service is ended;

Further, the MME900 further includes:

a second setting module, configured to set, after the first receiving module receives a CSFB service end notification message sent by an MSC/VLR, an unreturned indication if the first SGs association exists on the MME, where the unreturned indication is used to indicate that the UE does not return to an LTE network after the CSFB service is ended.

Further, the MME900 further includes:

Optionally, the MME900 further includes:

a starting module, configured to start a regression timer according to the CSFB service end notification message after the first receiving module receives the CSFB service end notification message sent by the MSC/VLR.

Further, the MME900 further includes:

and a stopping module, configured to stop the regressive timer if a paging request message sent by the MSC/VLR is received, or the UE is determined to regress to the LTE network after the CSFB service is ended.

Further, the determining module is specifically configured to: and if the regression timer is overtime and the non-regression indication exists, determining that the UE does not regress to the LTE network after the CSFB service is finished.

Further, the MME900 further includes:

and a deleting module, configured to delete the non-regression indication if it is determined that the UE regresses to the LTE network after the CSFB service is ended after the non-regression indication is set by the second setting module.

Further, the MME900 further includes:

a second sending module, configured to send an indication message to the MSC/VLR if the determining module determines that the UE does not return to the LTE network after the CSFB service is ended, where the indication message is used to indicate the MSC/VLR to delete the second SGs association of the UE on the MSC/VLR.

Optionally, the indication message is a separation indication message; the MME900 further includes:

and a fourth receiving module, configured to receive the detach acknowledgement message sent by the MSC/VLR after the second sending module sends the indication message to the MSC/VLR.

Further, the detach indication message includes a detach type, which is detached from the EPS IMSI.

Further, the determining module is specifically configured to: and if receiving the uplink message sent by the UE or receiving a context request message containing the UE identity identifier sent by a new MME, determining that the UE returns to the LTE network after the CSFB service is finished.

Wherein, the uplink message is a tracking domain update request message or an extended service request message or a service request message.

Further, the first setting module is specifically configured to:

setting a state of the first SGs association to null; or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

Optionally, the CSFB service includes:

circuit switched CS voice service; or, CS video services; or, a CS location service; alternatively, the CS supplements the service.

Optionally, the MME900 further includes:

and the counting module is used for counting the times of the CSFB service ending of the UE after the first receiving module receives a circuit switched fallback CSFB service ending notification message sent by a Mobile Switching Center (MSC)/Visitor Location Register (VLR).

The MME of this embodiment may be configured to execute the technical solution of the third embodiment of the method, and the implementation principle and the technical effect are similar, which are not described herein again.

In the embodiment of the invention, the MME deletes the local SGs association of the UE after receiving the CSFB service end notification message of the UE sent by the MSC/VLR, so that even if the MSC/VLR initiates the SGs interface paging to the MME, the MME can directly refuse the SGs interface paging of the MSC/VLR because the SGs association of the UE does not exist locally, the MSC/VLR directly initiates the air interface paging of the UE, thereby avoiding multiple overtime retransmission initiated to the MME, reducing the delay time of MT calling and greatly increasing the success probability of MT calling.

Fig. 10 is a schematic structural diagram of an MSC/VLR100 according to a tenth embodiment of the present invention. As shown in fig. 10, the MSC/VLR100 includes:

a processor (processor)11, a communication Interface (communication Interface)12, a memory (memory)13, and a communication bus 14. Wherein:

the processor 11, the communication interface 12, and the memory 13 communicate with each other via a communication bus 14.

A communication interface 12 for communication with an external device such as an MME.

The processor 11 is configured to execute the program 132, and may specifically execute the relevant steps in the first embodiment or the second embodiment.

In particular, the program 132 may include program code comprising computer operating instructions.

The processor 11 may be a central processing unit CPU or an application specific Integrated circuit asic or one or more Integrated circuits configured to implement embodiments of the present invention.

And a memory 13 for storing the program 132. The memory 13 may comprise a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory. In an alternative embodiment, the procedure 132 may specifically be configured to enable the MSC/VLR100 to perform the following steps:

determining that the CSFB service of the UE is ended;

and deleting the first SGs association of the UE on the MSC/VLR.

For specific implementation of each step in the program 132, reference may be made to corresponding steps and corresponding descriptions in units in the foregoing first embodiment or second embodiment, which are not described herein again. It can be clearly understood by those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described devices and modules may refer to the corresponding process descriptions in the foregoing first embodiment or second embodiment, and are not described again here.

Fig. 11 is a schematic structural diagram of an MME200 according to an eleventh embodiment of the present invention. As shown in fig. 11, the MME200 includes:

a processor (processor)21, a communication Interface (Communications Interface)22, a memory (memory)23, and a communication bus 24. Wherein:

the processor 21, the communication interface 22, and the memory 23 communicate with each other via a communication bus 24.

A communication interface 22 for communication with external devices such as MSC/VLR.

The processor 21 is configured to execute the program 232, and may specifically perform the relevant steps in the third embodiment.

In particular, the program 232 may include program code that includes computer operating instructions.

The processor 21 may be a central processing unit CPU or an application specific Integrated circuit asic or one or more Integrated circuits configured to implement embodiments of the present invention.

And a memory 23 for storing a program 232. The memory 23 may comprise a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory. In an alternative embodiment, the procedure 232 may specifically be configured to enable the MME200 to perform the following steps:

receiving a CSFB service end notification message sent by an MSC/VLR, wherein the MSC/VLR is an MSC/VLR associated with a first SGs association of UE on the MME, and the CSFB service end notification message is sent by the MSC/VLR when the CSFB service of the UE is determined to be ended;

deleting the first SGs association.

For specific implementation of each step in the program 232, reference may be made to corresponding steps and corresponding descriptions in units in the third embodiment, which are not described herein again. It can be clearly understood by those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described devices and modules may refer to the corresponding process descriptions in the foregoing third embodiment, and are not described again here.

Those of ordinary skill in the art will understand that: all or a portion of the steps of implementing the above-described method embodiments may be performed by hardware associated with program instructions. The program may be stored in a computer-readable storage medium. When executed, the program performs steps comprising the method embodiments described above; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for updating a state, comprising:

the MSC/VLR sends a CSFB service ending notification message to a mobile management entity MME, wherein the MME is an MME associated with a first SGs association of the UE on the MSC/VLR;

the MSC/VLR sends a paging request message to the MME;

the MSC/VLR receives an indication message sent by the MME after the MME determines that the UE does not return to a Long Term Evolution (LTE) network after the CSFB service is finished;

and the MSC/VLR deletes the first SGs association state according to the indication message.

2. The method according to claim 1, wherein the indication message is a paging reject message, and the paging reject message contains a second cause value indicating separation from an evolved packet system EPS service international mobile subscriber identity IMSI;

3. The method of claim 1, wherein the indication message is a detach indication message;

4. The method of claim 3, wherein the detach indication message contains a detach type, and wherein the detach type is detached from an EPS service IMSI.

5. The method of any one of claims 1 to 3, further comprising:

and initiating air interface paging to the UE.

6. The method according to any of claims 1-3, wherein the CSFB service end notification message is a release request message, and wherein the release request message includes a first cause value, and wherein the first cause value is used to indicate that the CSFB service of the UE is ended by the MME.

7. The method according to any of claims 1-3, wherein the deleting the first SGs association of the UE at the MSC/VLR comprises:

setting a state of the first SGs association to null; or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

8. The method according to any of claims 1-3, wherein the CSFB service comprises:

9. A method for updating a state, comprising:

a mobility management entity MME receives a circuit switched fallback CSFB service end notification message sent by a mobile switching center MSC/visitor location register VLR, wherein the MSC/VLR is an MSC/VLR associated with a first SGs association of user equipment UE on the MME, and the CSFB service end notification message is sent by the MSC/VLR when the CSFB service of the UE is determined to be ended;

determining that the UE does not return to a Long Term Evolution (LTE) network after the CSFB service is finished;

deleting the first SGs association;

and after determining that the UE does not return to a Long Term Evolution (LTE) network after the CSFB service is finished, sending an indication message to the MSC/VLR, wherein the indication message is used for indicating the MSC/VLR to delete the second SGs association of the UE on the MSC/VLR.

10. The method of claim 9, wherein the CSFB service end notification message is a detach request message, and wherein the detach request message is used to instruct the MME to delete the first SGs association.

11. The method of claim 9, wherein the CSFB service end notification message is a release request message, and wherein the release request message comprises a first cause value, and wherein the first cause value is used to indicate that the CSFB service of the UE is ended.

12. The method according to claim 9, wherein after the MME receives a circuit switched fallback CSFB service end notification message sent by a mobile switching center MSC/visitor location register VLR, the method further comprises:

13. The method of claim 12, further comprising:

receiving a paging request message sent by the MSC/VLR;

14. The method according to claim 12 or 13, wherein after the MME receives a circuit switched domain fallback CSFB service end notification message sent by a mobile switching center MSC/visitor location register VLR, the method further comprises:

15. The method of claim 14, further comprising:

16. The method of claim 14, wherein the determining that the UE does not return to a long term evolution, LTE, network after the CSFB service is over comprises:

17. The method of claim 12 or 13 or 15 or 16, further comprising, after said setting a no-regression indication:

and if the UE returns to the LTE network after the CSFB service is finished, deleting the non-returning indication.

18. The method of claim 9, wherein the indication message is a paging reject message, and wherein the paging reject message contains a second cause value indicating separation from an Evolved Packet System (EPS) service International Mobile Subscriber Identity (IMSI).

19. The method of claim 9, wherein the indication message is a detach indication message.

20. The method of claim 19, wherein the detach indication message comprises a detach type, and wherein the detach type is detached from an EPS service IMSI.

21. The method of claim 15, wherein the determining that the UE reverts to an LTE network after the CSFB service ends comprises:

22. The method of claim 21, wherein the uplink message is a tracking domain update request message or an extended service request message or a service request message.

23. The method according to any of claims 9-12, wherein said deleting the first SGs association comprises:

setting a state of the first SGs association to null; or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

24. The method according to any of claims 9-12, wherein the CSFB service comprises:

25. A mobile switching center MSC/visitor location register VLR, comprising:

a first sending module, configured to send a CSFB service termination notification message to a mobility management entity MME, where the MME is an MMEE associated with a first SGs association of the UE on the MSC/VLR;

a second sending module, configured to send a paging request message to the MME;

a first receiving module, configured to receive an indication message sent by the MME after determining that the UE does not return to a long term evolution LTE network after the CSFB service is ended;

and the setting module is used for deleting the association of the first SGs according to the indication message.

26. The MSC/VLR according to claim 25, wherein the indication message is a paging reject message containing a second cause value indicating separation from an evolved packet system EPS service international mobile subscriber identity IMSI;

27. The MSC/VLR according to claim 25, wherein said indication message is a detach indication message; the setting module is specifically configured to: and deleting the first SGs association according to the separation indication message.

28. The MSC/VLR of claim 27 wherein the detach indication message contains a detach type, which is detached from an EPS service IMSI.

29. The MSC/VLR of any of claims 25-27, further comprising:

and the paging module is used for initiating air interface paging of the UE.

30. The MSC/VLR of any of claims 25-27, wherein the CSFB service end notification message is a release request message, the release request message comprising a first cause value, and the first cause value is used to indicate that the CSFB service of the UE is ended by the MME.

31. The MSC/VLR of any one of claims 25-27, wherein the setting module is specifically configured to:

setting a state of the first SGs association to null; or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

32. The MSC/VLR of any of claims 25-27, wherein the CSFB service comprises:

33. A Mobility Management Entity (MME), comprising:

a first setting module, configured to delete the first SGs association if the determining module determines that the UE does not return to the LTE network after the CSFB service is ended;

further comprising:

a first sending module, configured to send an indication message to the MSC/VLR if the determining module determines that the UE does not return to the LTE network after the CSFB service is ended, where the indication message is used to indicate the MSC/VLR to delete the second SGs association of the UE on the MSC/VLR.

34. The MME of claim 33, wherein the CSFB service end notification message is a detach request message, wherein the detach request message is used to instruct the MME to delete the first SGs association.

35. The MME of claim 33, wherein the CSFB service end notification message is a release request message comprising a first cause value indicating that the CSFB service of the UE is ended.

36. The MME of claim 33, further comprising:

a second setting module, configured to set, after the first receiving module receives a circuit switched fallback CSFB service end notification message sent by a mobile switching center MSC/visitor location register VLR, an unreturned indication if the first SGs association exists on the MME, where the unreturned indication is used to indicate that the UE does not return to an LTE network after the CSFB service ends.

37. The MME of claim 36, further comprising:

a second receiving module, configured to receive a paging request message sent by the MSC/VLR;

38. The MME of claim 36 or 37, further comprising:

and the starting module is used for starting a regression timer according to the CSFB service end notification message after the first receiving module receives the CSFB service end notification message sent by the mobile switching center MSC/visitor location register VLR.

39. The MME of claim 38, further comprising:

a stopping module, configured to stop the regressive timer if a paging request message sent by the MSC/VLR is received, or the determining module determines that the UE regresses to the LTE network after the CSFB service is ended.

40. The MME of claim 38, wherein the determining module is specifically configured to: and if the regression timer is overtime and the non-regression indication exists, determining that the UE does not regress to the LTE network after the CSFB service is finished.

41. The MME of any of claims 36, 37, 39, and 40, further comprising:

and a deleting module, configured to delete the non-regression indication if the determining module determines that the UE regresses to the LTE network after the CSFB service is ended after the non-regression indication is set by the second setting module.

42. The MME of claim 33, wherein the indication message is a paging reject message, wherein the paging reject message comprises a second cause value indicating separation from EPS traffic IMSI.

43. The MME of claim 33, wherein the indication message is a detach indication message.

44. The MME of claim 43, wherein the detach indication message comprises a detach type, and wherein the detach type is detached from an EPS IMSI.

45. The MME of claim 39, wherein the determining module is specifically configured to: and if receiving the uplink message sent by the UE or receiving a context request message containing the UE identity identifier sent by a new MME, determining that the UE returns to the LTE network after the CSFB service is finished.

46. The MME of claim 45, wherein the uplink message is a tracking domain update request message or an extended service request message or a service request message.

47. The MME of any one of claims 33 to 35, wherein the first setting module is specifically configured to:

setting a state of the first SGs association to null; or,

deleting context information associated with the first SGs; or,

setting a state of the first SGs association to invalid; or,

setting the state associated with the first SGs as illegal; or,

48. The MME of any one of claims 33 to 35, wherein the CSFB service comprises: