WO2009049515A1

WO2009049515A1 - Method, device and system of called recovery in mobile switching center pool

Info

Publication number: WO2009049515A1
Application number: PCT/CN2008/072366
Authority: WO
Inventors: Biao Zhang; Hualin Luo
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2007-10-18
Filing date: 2008-09-16
Publication date: 2009-04-23
Also published as: CN101150781B; CN101150781A

Abstract

A method of called recovery in mobile switching center pool is disclosed. The method includes: a back-up mobile switching center of a called terminal receiving a PRN message which is transmitted by a home location register; a back-up of the called terminal obtaining a MSRN distributed by a called terminal after the MSC of receiving called terminal paging response executing analog location updating to the HLR; a backup MSC of the called terminal taking the MSRN of the called terminal in a PRN response message to transmit to the HLR. Another method of called recovery in a MSC POOL and a device and a system of called recovery in the MSC POOL are disclosed.

Description

Method, device and system for recovering a called call in a mobile switching center pool This application claims to be submitted to the China Intellectual Property Office on October 18, 2007, with the application number of 200710181536. 8 , and the invention name is "Recovered by the called mobile switching center pool. The priority of the Chinese Patent Application, the entire disclosure of which is hereby incorporated by reference.

Technical field

The present invention relates to the Mobile Switching Center Pool (MSC POOL) technology, and more particularly to a method, apparatus and system for recovering a called party in an MSC POOL.

Background technique

3GPP23. 236 proposes a completely different networking mode from the traditional networking. A radio network controller (RNC) / base station controller (BSC) can be connected to multiple MSCs (mobile switching centers), and MSCs are pooled. Mode work, that is, multiple MSCs form the MSC P00L. MSC POOL has many advantages. For example, each MSC can load-sharing, reduce C/D port signaling between the MSC and the Home Location Register (HLR), and reduce the E-interface message capacity between the MSCs.

In the process of the call initiated by the calling terminal to the called terminal, the HLR needs to obtain the MSRN of the called terminal, but the MSC that needs to provide the service for the called terminal works normally. If the MSC fails due to a failure, the MSC corresponds to When the terminal acts as the called terminal, it will cause the call to fail.

At present, the visitor location register (VLR) backup technology can be used, that is, the user data of the VLR backup terminal in the MSC that sends the paging to the called terminal, and the backup MSC initiates a call to the called terminal to ensure that the call is successful. However, the call flow when the terminal is called as the first time in the faulty MSC, because the PRN message sent by the calling terminal HLR for the first time, does not directly send the PRN message to the MSC as the backup, in the subsequent steps. The PRN response message for the PRN message is not received, so the HLR cannot obtain the MSRN of the terminal when the terminal makes the first call, so the terminal fails to make the called for the first time.

The above prior art method solves the problem that the call of the terminal under the MSC is successful when the MSC is down, but the terminal can be implemented when the terminal is called for the second time. The call is successful, that is, the location update is completed in the first call as the called party, and the updated MSC is used in the second time as the called party to enable the HLR to acquire the MSRN of the called terminal, thereby making the call successful and failing to implement the fault. When the terminal on the MSC is called as the called for the first time, the call is successful. Summary of the invention

The embodiment of the invention provides a method, a device and a system for recovering a called party in an MSC POOL, which can enable a terminal in a MSC POOL to be successfully called when the terminal is the first time. The technical solution of the embodiment of the present invention is implemented as follows:

A method for recovering a called call in a pool of a mobile switching center, the method comprising:

Receiving a roaming number message sent by the home location register;

Obtaining a roaming number assigned to the called terminal, where the roaming number is allocated by the mobile switching center that receives the paging response of the called terminal to the called terminal;

The roaming number of the called terminal is carried in the providing roaming number response message and sent to the home location register.

A mobile switching center in a mobile switching center pool, the mobile switching center includes: a processing module, configured to acquire, after the mobile switching center that receives the paging response of the called terminal, performs location update to the home location register, and allocates to the called terminal Roaming number

And a sending module, configured to send the roaming number of the called terminal in the processing module to the home location register in the providing roaming number response message.

A home location register in the mobile switching center pool, the home location register includes: a location update processing module, configured to parse the mobile switching center that receives the paging response of the called terminal in the sent location update request, and carry the indication to resend a specific extension cell that provides a roaming number message;

a message processing module, configured to remove, according to the parsing result of the specific extended cell by the location update processing module, the roaming number message sent to the backup mobile switching center of the called terminal, and send the message through the signaling transfer point Receiving, by the mobile switching center that receives the paging response of the called terminal, resending the roaming number providing message; receiving the return of the mobile switching center that receives the paging response of the called terminal A roaming number response message is provided, and the roaming number assigned to the called terminal carried in the response message for providing the roaming number is obtained.

A signaling transfer point in a pool of mobile switching centers, the signaling transfer point comprising:

a parsing module, configured to parse the mobile switching center that receives the paging response of the called terminal, in the sent location update request, carrying the indication to resend the specific extended cell that provides the roaming number message; and the message processing module, configured to receive the home location register Sending a roaming number message to the backup mobile switching center of the called terminal and storing it; and transmitting a location update request for deleting the specific extended cell to the home location according to the parsing result of the specific extended cell by the parsing module And storing the stored roaming number providing message to a mobile switching center that receives a paging response of the called terminal.

A system for called recovery in a pool of mobile switching centers, the system comprising:

The backup mobile switching center of the called terminal is configured to acquire, by the mobile switching center that receives the paging response of the called terminal, the roaming number assigned to the called terminal after performing location update to the home location register, and carry the roaming number in the providing The roaming number response message is sent to the home location register; the mobile switching center receiving the paging response of the called terminal is configured to receive a paging response of the called terminal, and allocate a roaming number to the called terminal.

A computer program product comprising computer program code, which when executed by a computer, causes the computer to perform any one of claims 1 to 5 or 6 to 10 A step of.

A computer readable storage medium storing computer program code, which when executed by a computer, causes the computer to perform any of claims 1 to 5 or 6 to 10 One step.

It can be seen that, in the method, device, and system for recovering a called party in an MSC POOL provided by the embodiment of the present invention, after the MSC receiving the paging response of the called terminal performs location update to the HLR, the backup MSC of the called terminal acquires the received called party. The MSC of the terminal paging response is the MSRN allocated by the called terminal, and the MSRN of the called terminal is carried in the PRN response message and sent to the HLR; or, the receiving terminal is received. When the MSC responding to the HLR performs location update to the HLR, it notifies the retransmission of the PRN message, that is, notifies the MSC that receives the paging response of the called terminal to resend the PRN message, so that the HLR can receive the MSC from the called terminal. On, get the MSRN that it newly assigned to the called terminal. Through the above two methods, the terminal under the faulty MSC is realized. When the called party is called for the first time, the HLR can obtain the MSRN of the called terminal, thereby realizing the successful call of the terminal when making the called for the first time.

DRAWINGS

1 is a flowchart of a method for recovering a called party in an MSC POOL according to an embodiment of the present invention; FIG. 2 is a flowchart of an embodiment of a method for recovering a called party in an MSC POOL according to an embodiment of the present invention. ;

FIG. 3 is a flowchart of an embodiment of a method for recovering a called party in an MSC POOL according to an embodiment of the present invention;

4 is a flowchart of an embodiment of a method for recovering a called party in an MSC POOL implemented on an MSC according to an embodiment of the present invention;

5 is a flowchart of a method for recovering a called party in a second MSC POOL according to an embodiment of the present invention; FIG. 6 is a flow chart of a method for recovering a called party in a second MSC POOL according to an embodiment of the present invention;

7 is a flow chart of an embodiment of a method for recovering a called party in a second MSC POOL according to an embodiment of the present invention;

8 is a schematic structural diagram of an MSC in a first MSC POOL according to an embodiment of the present invention;

9 is a schematic structural diagram of an MSC in a second MSC POOL according to an embodiment of the present invention;

10 is a schematic structural diagram of an HLR in an MSC POOL according to an embodiment of the present invention;

FIG. 11 is a schematic structural diagram of STP in an MSC POOL according to an embodiment of the present invention.

detailed description

In MSC POOL, it is assumed that a certain MSC is identified by MSC1. When the terminal under the MSC1 is called, the call flow mainly includes the following steps:

1) The calling gateway office requests the HLR for the roaming number (MSRN) of the called terminal; 2) The HLR sends a Roaming Number (PRN) message to the Signaling Transfer Point (STP), and the STP sends the PRN message to the MSC1;

3) MSC1 allocates an MSRN to the called terminal, and carries the allocated MSRN in the PRN response message to the HLR;

4) The HLR sends the MSRN of the called terminal to the calling gateway office, and the calling gateway office routes the call initiated by the calling terminal to the MSC1 according to the MSRN.

Through the above steps 1) - 4), the call initiated by the calling terminal to the called terminal is successful, and the HLR acquires the MSRN of the called terminal, which is the key to realizing the successful call of the called terminal. However, the above procedure is based on the premise that the MSC1 is working properly. If the MSC1 is down due to a fault, the terminal corresponding to the MSC1 will be unable to follow the above procedure if the terminal is the called terminal. There is currently a solution to the above problem, in which a visitor location register (VLR) backup technique is used, that is, user data of a VLR backup terminal in an MSC that issues a page to a called terminal, and a route is also used. Priority or Signaling Link Control Part (SCCP) destination signaling point active-standby sharing technology. Among them, the routing priority or the SCCP destination signaling point master-slave sharing technology, either of which can be used to configure the standby MSC for the primary MSC where the terminal is located; and the VLR backup technology, including centralized backup and decentralized Backup, where centralized backup refers to centralized backup of user data of all terminals in the network to one MSC. The MSC is called a centralized backup MSC. Non-centralized backup means that user data of different terminals is backed up to different MSCs. Each terminal has its own backup MSC. The two backup methods can be selected. The backup terminal user data includes the basic data and location area of the terminal. The location area indicates the current location of the terminal, which is convenient for targeted. The paging of the terminal is sent in the area, which solves the problem that the whole network paging cannot be delivered in the MSC POOL.

The solution mainly includes:

1 The HLR sends a PRN message to the STP, and the STP determines that the advanced route between the MSC1 and the MSC1 is faulty, and sends the PRN message to the MSC2 in the MSC POOL that is not down, that is, the MSC2 is the backup MSC of the MSC1, and routes from the low priority. Sending the PRN message;

2 Sending a page to the called terminal on the MSC2, the access side will follow the principle of load sharing. The paging response sent by the called terminal is sent to the MSC3 in the MSC POOL;

3 MSC3 sends a location update to the HLR, informing the HLR that the called terminal location has been updated to MSC 3;

This step may include the MSC3 sending a location update request to the HLR; the HLR sends a cancel location request to the STP; the STP sends the cancel location request to the MSC2; the MSC2 clears the internally backed up terminal user data; the HLR then inserts the called terminal into the MSC3. User data; MSC3 allocates a temporary mobile subscriber identity (TMS I) that can identify itself to the called terminal; MSC3 backs up the updated subscriber data to MSC2; 1~3 is the first time when the terminal is called as the called party under the faulty MSC The call flow, after the PRN message sent by the HLR in the first step, does not receive the PRN response message for the PRN message in the subsequent step, so the HLR cannot obtain the MSRN of the terminal when the terminal makes the called for the first time. Therefore, it is a failure for the terminal to make a call for the first time.

When the called terminal is called as the called for the second time, the MSC 3 can use the steps 1) - 3) described above to enable the HLR to obtain the MSRN of the called terminal in the call, thereby realizing the successful call of the called terminal.

The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

First, a method for recovering a called party in the first MSC POOL according to an embodiment of the present invention is introduced.

FIG. 1 is a flowchart of a method for recovering a called party in an MSC POOL according to an embodiment of the present invention. Before the process shown in FIG. 1 is started, according to the common knowledge of those skilled in the art, the backup MSC of the called terminal receives the PRN message sent by the HLR through the STP, and issues a page to the called terminal; receives the called terminal paging. The responding MSC allocates TMS I to the called terminal and performs location update to the HLR.

The process shown in Figure 1 includes:

Step 101: The backup MSC of the called terminal receives the PRN message sent by the HLR.

Step 102: The backup MSC of the called terminal acquires the MSRN allocated by the MSC that receives the paging response of the called terminal to the called terminal after performing location update to the HLR.

In this step, the method for obtaining the MSRN may be that the MSC that receives the paging response of the called terminal will be The MSRN allocated by the called terminal is carried in a private message and sent to the backup MSC of the called terminal.

Step 103: The backup MSC of the called terminal carries the MSRN of the called terminal in a PRN response message and sends it to the HLR.

In the first embodiment of the present invention, the method for recovering the called call in the MSC POOL, after the MSC receiving the paging response of the called terminal performs location update to the HLR, the backup MSC of the called terminal acquires the paging response of the received called terminal. The MSRN is the MSRN allocated by the called terminal, and the MSRN of the called terminal is carried in the PRN response message and sent to the HLR to implement the terminal under the faulty MSC. When the first call is made, the HLR can obtain the The MSRN of the called terminal, so that the call of the terminal when the terminal is called for the first time is successful.

The first method provided by the embodiment of the present invention can be implemented on the MSC. The following describes the embodiments implemented on the MSC in combination with specific application scenarios.

First, the first method provided by the embodiment of the present invention can still use the VLR backup technology and the route priority technology.

In the VLR backup technology, the backup mode can be divided into centralized backup and non-centralized backup. In the centralized backup mode, the backup data of all terminals in the network is stored in the centralized backup MSC. The centralized backup MSC does not. Responsible for processing services, and according to the data configuration relationship, when the user data backup is required, other MSCs in the network store the user data that needs to be backed up to the centralized backup MSC; in the non-centralized backup mode, different terminals in the network correspond to each other. The backup MSCs of the different backup MSCs store the user data that needs to be backed up to the backup MSC corresponding to the terminal according to the identification information of the terminal.

In the route priority technology, when the STP forwards the message sent by the HLR, the route between the MSCs in the network is divided into high and low priorities, and the route between the STP and the destination MSC that directly sends the message to the current HLR is divided into High-priority routing, and the STP is divided into other MSCs other than the destination MSC that sends the message by the current HLR, and then the route to the destination MSC is divided into low-priority routes.

The following is an example of implementing the first method provided by the embodiment of the present invention on the MSC according to the VLR backup mode and the network where the called terminal is located, where the network is 2G and 3G. In the middle, the MSC and the VLR use a combined approach.

2 is a flow chart of an embodiment of a method for recovering a called party in an MSC POOL on an MSC according to an embodiment of the present invention.

It is assumed that the application scenario of this embodiment is as follows: In the VLR backup technology, centralized backup is used; the primary MSC of the called terminal is MSC A; the centralized backup MSC is MSC B; and the MSC receiving the called terminal paging response is MSC. C.

The process shown in Figure 2 includes:

Step 201: The HLR sends a PRN message to the STP, in order to acquire the MSRN from the MSC A.

Step 202: The STP sends a high priority route to the MSC A. The STP selects the low priority route to send the PRN message sent by the HLR to the MSC B that is backed up. After receiving the PRN message, the MSC B does not forward the PRN message, and the international mobile subscriber identity (IMSI) is retrieved from the PRN message. The terminal backup VLR corresponding to the IMS I is searched internally. The user data backed up by the terminal corresponding to the IMS I is sent to the terminal.

In this step, there are several possible situations in which MSC B sends a page:

a) When the called terminal is powered off, the MSC B directly returns the information of the called terminal to the HLR, and ends the process;

b) the called terminal is in the idle mode, and the location area (LA) information of the called terminal is taken out, and the paging is sent in the location area indicated by the LA, and the paging is performed by the IMSI;

c) The called terminal is in the connected state, and the LA is taken out, and the paging is sent in the location area indicated by the LA, and paging is performed by IMSI. After the MSC A fails, the calling terminal will drop the call, so the backup VLR corresponding to the called terminal, that is, the user data is not updated.

Step 203: After the called terminal receives the paging and makes a paging response, the access network (RAN) sends the paging response of the called terminal to the MSC C according to the load balancing algorithm, that is, the RAN searches for the called terminal. The call response is sent to a non-page originating office, and MSC C determines that the called terminal is not registered in this office.

In this step, the inter-domain non-access stratum node selection (ID匪S) cell in the paging response in the 3G network may carry the IMSI or the TMSI, and the paging response in the 2G network. IDNNS The IMSI is carried in the cell, but since the MSC B is a centralized backup MSC and does not process the service, the paging response will not be carried out regardless of whether the I匪NS cell in the paging response carries the IMSI or the TMSI. Send to MSC B.

Step 204: The MSC C sends a location update request to the HLR through the STP.

Step 205: After receiving the location update request, the HLR sends a cancel location request to the STP, which is used to cancel the location information of the called terminal. The STP sends the cancel location information request due to the high priority route fault of the STP to the MSC A. To the centralized backup of MSC B.

Step 206: After receiving the request for canceling the location information, the MSC B clears the user data in the VLR corresponding to the internal called terminal.

Step 207: The MSC B sends a cancel location confirmation message to the HLR through the STP.

Step 208: The HLR inserts the user data of the called terminal to the MSC C.

Step 209: The HLR sends a message of location update acceptance to the MSC C.

Step 210: The MSC C sends the TMSI allocated to the called terminal to the RAN, and the network resource identifier (NRI) in the allocated TMSI may identify the MSC C in the MSC POOL.

Step 211: The MSCC re-backups the user data corresponding to the called terminal, including the IMSI, the location area identifier (LAI), and the user status, to the MSC B, as the newly backed up user data in the MSC B after the called terminal is updated.

The above steps 204 to 211 complete the process of receiving the MSC of the called terminal's paging response and performing analog location update to the HLR.

Step 212: The MSC C allocates the MSRN to the called terminal, and sends the allocated MSRN to the MSC B through the Private Mobile Application Part (MAP) signaling.

In this step, the private message sent by the MSRN is implemented by using the private MAP signaling, which is a new signaling defined according to the semantics of the existing protocol. For the protocol semantics well known to those skilled in the art, no further details are provided herein. The private MAP signaling structure is as follows, where the MSRN-line is the carried MSRN allocated for the called terminal.

MSRNREDIRECT OPERATION :: = { ARGUMENT SEQUENCE {

{

MSRN [0] IMPLICIT OCTET STRING ( SIZE ( 4) ) , IMSI [2] IMPLICIT OCTET STRING ( SIZE ( 8) ) ,

MS I SDN [0] IMPLICIT OCTET STRING ( SIZE ( 4) ) OPTIONAL,

:: = loca lVa lue : 248

Step 213: The MSC B carries the MSRN in the PRN response message and returns it to the HLR.

In an embodiment of the method for recovering a called party in the first type of MSC POOL in the embodiment of the present invention, after the MSC that receives the paging response of the called terminal performs location update to the HLR, the centralized backup mode is used. The centralized backup MSC obtains the MSRN allocated by the MSC that receives the paging response of the called terminal, and the MSRN of the called terminal is carried in the PRN response message and sent to the HLR to implement the terminal under the faulty MSC. When the called party is called for the first time, the HLR can obtain the MSRN of the called terminal, thereby realizing the successful call of the terminal when the terminal is called for the first time.

FIG. 3 is a flowchart of an embodiment of a method for recovering a called party in an MSC POOL according to an embodiment of the present invention.

The application scenario of this embodiment is as follows: In the VLR backup technology, the non-centralized backup is used; the primary MSC of the called terminal is MSC A; the backup MSC of the called terminal is MSC B; and the called terminal receives the paging response. The MSC is the MSC C; the I匪NS cell in the paging response of the called terminal contains the TMSI allocated before the MSC A failure, and the non-access layer network node selection function (NAS) cell contains the IMSI.

The process shown in Figure 3 includes:

Steps 301 to 302 are the same as steps 201 to 202.

Step 303: The called terminal receives the paging and makes a paging response. The ID 匪S cell in the paging response includes the TMSI allocated to the called terminal before the MSC A failure, and the TMSI includes the NRI for MSC A is identified in the MSC POOL; the non-access stratum network node selection function in the paging response carries the IMS I in the NAS cell. The RAN finds the MSC A according to the NRI carried by the TMS I in the paging response, finds that the MSC A fails, and then sends the paging response to the MSC C in the MSC POOL according to the load balancing algorithm.

Step 304 to step 311 are the same as steps 204 to 211.

Step 312: The MSC C determines the backup MSC of the called terminal as the MSC B according to the NRI carried by the TMS I in the paging response, and allocates the MSRN to the called terminal, and allocates the MSRN according to the configuration relationship between the primary MSC and the standby MSC. It is sent to MSC B through private MAP signaling.

In this step, the structure of the private MAP signaling can be the same as that shown in step 212.

In the foregoing process shown in FIG. 3, if the RAN sends the paging response to the MSC B according to the load balancing algorithm, that is, it is sent to the backup MSC of the called terminal, the subsequent process of step 303 may be performed. In another way, the MSC B can directly update the location of the HLR, and allocate the MSRN to the called terminal, and then return the PRN response message carrying the MSRN to the HLR.

In an embodiment of the method for recovering a called party in the first type of MSC POOL in the embodiment of the present invention, the TMS I allocated by the faulty MSC carried in the paging response of the called terminal is used in the non-centralized backup mode. After the MSC that receives the paging response of the called terminal sends a location update to the HLR, the backup MSC of the called terminal obtains the MSRN allocated by the MSC that receives the paging response of the called terminal, and allocates the called MSRN. The MSRN of the terminal is carried in the PRN response message and sent to the HLR to implement the terminal under the faulty MSC. When the called party is called for the first time, the HLR can obtain the MSRN of the called terminal, thereby realizing the first time of the terminal. The call at the time of the call is successful.

FIG. 4 is a flowchart of an embodiment of a method for recovering a called party in an MSC POOL according to an embodiment of the present invention.

It is assumed that the application scenario of this embodiment is: the user data in the VLR is used for non-centralized backup; the primary MSC of the called terminal is MSC A; the backup MSC corresponding to the called terminal is MSC B; receiving the called terminal paging response The MSC is MSC C; when the called terminal is called, the MSC A fails to be down; the ID 匪S cell in the paging response of the called terminal carries the IMS I, and the NAS cell carries the IMS I .

The process shown in Figure 4 includes:

Steps 401 to 402 are the same as steps 201 to 202. Step 403: The called terminal receives the paging and makes a paging response. In the paging response, the ID 匪S cell includes the IMS I, and the NAS cell carries the IMS I. The RAN searches for the correspondence between the IMS I and the MSC according to the IMS I included in the IDNNS cell. The specific implementation can search for the correspondence between the IMS I and the Globa CN-ID or the signaling point, and find the backup MSC of the called terminal. For MSC B, the paging response is sent to MSC B.

Step 404: Considering the load balancing of the MSC POOL, the MSC B redirects the paging response to the MSC C according to the load of other MSCs in the MSC POOL. In this step, if the paging response of all terminals on the faulty MSC A is processed on the MSC B, the MSC B will be overloaded, so that a part of the paging response message may be redirected to other MSCs for processing. The called terminal paging response in this embodiment is redirected to the MSC C for processing.

Steps 405 to 414 are the same as steps 204 to 21 3 . When the private MAP signaling carrying the MSRN is sent to the MSC B in the step 41 3, the structure of the private MAP signaling may be the same as that shown in step 212.

In this embodiment, step 405 may not be performed, and the paging response message is directly processed by the MSC B, that is, the operations completed by the MSC C in steps 405 to 414 are completed by the MSC B, but the MSC B does not perform the use of the private message. The step of sending the MSRN, because if the MSC B directly processes the paging response message, the MSRN of the called terminal itself is allocated by the MSC B, and the MSC B transmits it in the PRN response message after the MSRN is allocated. Give it to the HLR.

In the embodiment of the first embodiment of the present invention, the method for recovering the called MSC POOL is implemented on the MSC, and the IMS I allocated by the faulty MSC carried in the paging response of the called terminal is used in the non-centralized backup mode. After the MSC that receives the paging response of the called terminal sends a location update to the HLR, the backup MSC of the called terminal acquires the MSRN that is the paging terminal that receives the paging response of the called terminal, and allocates the MSRN to the called terminal, and the called terminal The MSRN is carried in the PRN response message and sent to the HLR to implement the terminal under the faulty MSC. When the called party is called for the first time, the HLR can obtain the MSRN of the called terminal, thereby realizing that the terminal is called for the first time. The call was successful.

Next, a method for called recovery in the second MSC POOL according to the embodiment of the present invention is introduced. FIG. 5 is a flowchart of a method for recovering a called party in a second MSC POOL according to an embodiment of the present invention. Before the process shown in FIG. 5 starts, according to common knowledge of those skilled in the art, the backup MSC of the called terminal receives the HLR through the STP. The transmitted PRN message is sent to the called terminal; the MSC receiving the called terminal's paging response allocates the TMSI to the called terminal.

The process shown in Figure 5 includes:

Step 501: The MSC that receives the paging response of the called terminal, when performing location update to the HLR through the STP, notifies the resending of the PRN message.

Step 502: The MSC that receives the paging response of the called terminal receives the retransmitted PRN message. Step 503: The MSC that receives the paging response of the called terminal sends the MSRN that is allocated to the called terminal to the HLR in the PRN response message.

In the second embodiment of the present invention, the method for recovering the called party in the second MSC POOL, when the MSC receiving the paging response of the called terminal sends a location update to the HLR, notifies the resending of the PRN message, that is, notifies the MSC that receives the paging response from the called terminal. Resending the PRN message, so that the HLR can obtain the newly allocated MSRN for the called terminal from the MSC that receives the paging response of the called terminal, and implement the terminal under the faulty MSC. When the first call is made, the HLR The MSRN of the called terminal can be obtained, so that the call success when the terminal is called for the first time is realized.

The method for recovering the called party in the second MSC POOL according to the embodiment of the present invention may be implemented on the HLR or the STP. In the following two implementation manners respectively, two embodiments of the second method of the embodiment of the present invention are given. In these embodiments, the MSC and the VLR are in a combined manner.

FIG. 6 is a flow chart of an embodiment of a method for recovering a called party in a second MSC POOL according to an embodiment of the present invention. It is assumed that the application scenario of this embodiment is: the primary MSC of the called terminal is MSC A; the standby MSC is MSC B; and the MSC receiving the paging response of the called terminal is MSC C; the method is implemented on the HLR.

The process shown in Figure 6 includes:

Step 601: The HLR sends a PRN message to the STP, and the purpose is to obtain the MSRN that the MSC A allocates for the called terminal.

Step 602: The high priority routing fault of the STP to the MSC A, and the PRN sent by the HLR is eliminated. The information is sent to the MSC B for centralized backup, and the lower priority route is taken. After receiving the PRN message, MSC B does not forward the PRN message.

Step 603: The MSC B extracts the IMS I from the PRN message, searches for the terminal backup VLR corresponding to the IMS I, and searches for the terminal backup user data corresponding to the IMSI, and sends the paging.

b) The called terminal is in the idle mode, the LA is taken out, the paging is sent in the LA indication location area, and the paging is performed by the IMSI;

c) The called terminal is in the connected state, the LA is taken out, the paging is sent in the LA indication location area, and the paging is performed by the IMS I. After the MSC A fails, the calling terminal will drop the call, so the backup VLR data corresponding to the called terminal is not updated.

For the above cases b) and c), MSC B ends the paging process after paging, and returns a reason value "user unreachable" to the HLR.

Step 604: After the called terminal receives the paging and makes a paging response, the RAN sends the paging response of the called terminal to the MSC C according to the load balancing algorithm, that is, the RAN sends the paging response of the called terminal to one. The non-paging originating office, MSC C determines that the called terminal is not registered in this office.

Step 605: The MSC C sends a location update request to the HLR through the STP. The location update request carries a specific extension cell, and is used to tell the HLR to obtain the MSRN of the called terminal from the MSC C, that is, to inform the HLR to resend the PRN message to the MSC C.

In this step, the structure of the specific extension cell can be as follows, wherein the part after the extens ionConta iner is the content of the notification resending PRN message.

updateLocat ion OPERATION

ARGUMENT

updateLocat ionArg SEQUENCE {

Ims i OCTET STRING ( SIZE ( 3 . . 8 ) ) ,

msc-Number [1] IMPLICIT OCTET STRING ( SIZE ( 1 . . 20 ) ) ( SIZE ( 1 . . 9 ) ) , Vlr- Number OCTET STRING ( SIZE ( 1 . . 20 ) ) ( SIZE ( 1 . . 9 ) ) , lms i [10] IMPLICIT OCTET STRING ( SIZE ( 4 ) ) OPTIONAL, extens ionConta iner SEQUENCE {

Pr ivateExtens ionLi s t [0] IMPLICIT SEQUENCE ( SIZE ( 1 . . 10 ) ) OF SEQUENCE {

Ext ld MAP-EXTENSION . &extens ionld ( { II Ox (2a 86 08 08 08 08 08 05) extType MAP-EXTENSION . &Extens ionType ( {

PRN-REQ;

· · · } { aext ld } ) OPTIONAL} OPTIONAL,

Pes- Extens ions [1] IMPLICIT SEQUENCE {

. . . } OPTIONAL,

. . . OPTIONAL, Step 606: After receiving the location update request, the HLR determines that the location update request has a specific extended cell.

Step 607: The HLR sends a request for canceling the original location information of the called terminal to the STP. The STP sends the cancel location information request to the MSC B for centralized backup due to the high priority routing fault of the STP to the MSC A.

Step 608: After receiving the request for canceling the location information, the MSC B clears the user data in the VLR corresponding to the internal called terminal.

Step 609: The MSC B sends a cancel location confirmation message to the HLR through the STP.

Step 610: The HLR inserts the user data of the called terminal to the MSC C.

Step 611: The HLR sends a message of location update acceptance to the MSC C.

Step 612: The MSC C sends the TMSI allocated to the called terminal to the access side, and the NRI in the allocated TMSI can uniquely identify the MSC C in the MSC POOL.

Step 613: The MSC C sends the user data of the called terminal to the MSC B, including the IMSI, the LAI, and the user status, etc., for backing up the user data in the MSC B. Step 614: The HLR sends a PRN message to the STP, and the purpose is to take the MSRN corresponding to the called terminal to the MSC C, and the STP sends the PRN message to the MSC C through the high priority route.

Step 615: The MSC C allocates the MSRN to the called terminal, and carries the allocated MSRN in the PRN response message and sends it to the HLR.

In an embodiment of the second MSC POOL in the embodiment of the present invention, the called party resumes the implementation on the HLR, and the MSC that receives the paging response of the called terminal notifies the HLR to resend the PRN message, and the HLR re-re- Sending a PRN message to the MSC that receives the paging response of the called terminal, and the MSC receiving the paging response of the called terminal returns a PRN response message carrying the called terminal MSRN to the HLR, thereby realizing the terminal under the faulty MSC, in the first time When the called party is called, the HLR can obtain the MSRN of the called terminal, thereby realizing the successful call of the terminal when the terminal is called for the first time.

FIG. 7 is a flow chart of an embodiment of a method for recovering a called party in a second MSC POOL according to an embodiment of the present invention.

It is assumed that the application scenario of this embodiment is: the primary MSC of the called terminal is MSC A; the MSC that is centrally backed up is MSC B; and the MSC that receives the paging response of the called terminal is MSC C; the method is implemented on STP.

The process shown in Figure 7 includes:

Step 701: The HLR sends a PRN message to the STP, and the purpose is to obtain the MSRN allocated by the MSC A to the called terminal. The STP determines the high priority route fault to the MSC A, and stores the PRN message.

Steps 702 to 705 are the same as steps 602 to 605.

Step 706: After receiving the location update request sent by the MSC C, the STP determines that the location update request carries the specific extended cell. After the STP deletes the cell from the location update request, the STP sends the location update request to the HLR, and then sends the location update request to the HLR. The stored PRN message is sent to MSC C.

Step 707: The MSC C allocates the MSRN to the called terminal, and sends the MSRN to the HLR in the PRN response message.

In an embodiment of the second MSC POOL in the embodiment of the present invention, the called party resumes the STP, and the STP stores the PRN message sent by the HLR to the backup MSC of the called terminal, and receives the called terminal. The paging response MSC notifies the retransmission of the PRN message, so the STP will store the PRN. The message is sent to the MSC that receives the paging response of the called terminal, and the MSC that receives the paging response of the called terminal returns a PRN response message carrying the called terminal MSRN to the HLR, and implements the terminal under the faulty MSC, in the first time. When the called party is located, the HLR can obtain the MSRN of the called terminal, thereby realizing the successful call of the terminal when the terminal is called for the first time.

Next, an apparatus for recovering a called party in an MSC POOL according to an embodiment of the present invention is provided, including: two types of MSCs, an HLR, and an STP.

FIG. 8 is a schematic structural diagram of an MSC in an MSC POOL according to an embodiment of the present invention. The MSC includes: a processing module, configured to acquire, after the MSC that receives a paging response of the called terminal updates the location to the HLR, allocate the MSC to the called terminal. MSRN.

The sending module is configured to send the MSRN of the called terminal in the processing module to the HLR in a PRN response message.

The MSC in the first type of MSC POOL provided by the embodiment of the present invention acquires the MSRN allocated by the called terminal to the called terminal, and carries the MSRN of the called terminal in the PRN response message. To the HLR, the terminal under the faulty MSC is realized. When the called party is called for the first time, the HLR can obtain the MSRN of the called terminal, thereby realizing the successful call of the terminal when the terminal is called for the first time, saving the faulty MSC. When the terminal is called, the time required to achieve the call is successful.

In the first MSC provided by the embodiment of the present invention, the MSC may be the MSC that receives the paging response of the called terminal. In this case, the processing module may include: a receiving module, an allocating module, and an obtaining module.

The receiving module is configured to receive a paging response of the called terminal.

An allocation module, configured to allocate an MSRN to the called terminal.

An obtaining module, configured to acquire an MSRN allocated by the allocation module to the called terminal.

In the first MSC provided by the embodiment of the present invention, the MSC may not be the MSC that receives the paging response of the called terminal. In this case, the processing module includes: a receiving module, a redirection module, and an obtaining module.

a receiving module, configured to receive a paging response of the called terminal, and receive the paging of the received terminal The private message sent by the MSC, the MSC carrying the paging response of the called terminal is the MSRN allocated by the called terminal.

And a redirection module, configured to redirect, by the load balancing algorithm, the called terminal paging response received by the receiving module to another MSC in the MSC POOL, where the other MSC acts as an MSC that receives the called terminal paging response.

And an obtaining module, configured to obtain, by the private message received by the receiving module, the MSRN that is configured by the MSC that receives the paging response of the called terminal as the called terminal.

FIG. 9 is a schematic structural diagram of an MSC in a second MSC POOL according to an embodiment of the present invention. The MSC includes: a processing module, configured to receive a paging response of a called terminal; and notify a resend PRN message when performing location update to the HLR by using the STP; Assign the MSRN to the called terminal.

The transceiver module is configured to receive the retransmitted PRN message, and send the MSRN allocated by the processing module to the called terminal to be sent to the HLR in the PRN response message.

In the second embodiment of the present invention, when the MSC in the second MSC POOL performs location update to the HLR through the STP, it notifies that the PRN message is resent, that is, the MSC that receives the paging response from the called terminal resends the PRN message, so that the HLR can receive the PRN. Obtaining the newly allocated MSRN for the called terminal on the MSC of the called terminal paging response, and realizing the terminal under the faulty MSC, the HLR can obtain the MSRN of the called terminal when the called party is called for the first time, thereby realizing When the terminal makes a call for the first time, the call is successful, which saves the time required for the call to succeed when the terminal under the MSC is called.

The processing module of the MSC in the second MSC POOL of the embodiment of the present invention includes: a cell extension module and a processing execution module.

The cell expansion module is configured to provide the process execution module with a specific extension cell indicating to resend the PRN message.

The processing execution module is configured to receive a paging response of the called terminal, and perform a location update to the HLR by using the STP, and carry the specific extended cell provided by the cell extension module in the location update request, and notify the resending the PRN message. ; Assign the MSRN to the called terminal.

FIG. 10 is a schematic structural diagram of an HLR in an MSC POOL according to an embodiment of the present invention, where the HLR includes: The location update processing module is configured to parse, in the sent location update request, the MSC that receives the paging response of the called terminal, and carries a specific extended cell that indicates that the PRN message is resent.

a message processing module, configured to: according to the parsing result of the specific extended cell by the location update processing module, remove a PRN message sent to the backup MSC of the called terminal, and search for the called terminal by using the STP And responding to the MSC, resending the PRN message; receiving the PRN response message returned by the MSC that receives the paging response of the called terminal, and acquiring the MSRN allocated to the called terminal carried in the PRN response message.

In the embodiment of the present invention, the HLR in the MSC POOL parses the specific extended cell carried by the MSC in the location update, and removes the PRN message sent to the backup MSC of the called terminal by parsing the specific extended cell, and receives the PRN message. The MSC that responds to the called terminal's paging response re-transmits the PRN, so that the MSRN is obtained on the MSC after the location of the called terminal is updated, and the terminal under the faulty MSC is realized. When the called party is called for the first time, the HLR can obtain the The MSRN of the called terminal realizes the successful call of the terminal when the terminal is called for the first time, and saves the time required for the call to succeed when the terminal is called as the called terminal.

FIG. 11 is a schematic structural diagram of an STP in an MSC POOL according to an embodiment of the present invention. The STP includes: a parsing module, configured to parse an MSC that receives a paging response of a called terminal in a sent location update request, and carries an indication to resend a PRN message. Specific extension cell.

a message processing module, configured to receive a PRN message sent by the HLR to the backup MSC of the called terminal, and store the location update request of the specific extended cell according to the parsing result of the specific extended cell by the parsing module Sending to the HLR; transmitting the stored PRN message to the MSC receiving the paging response of the called terminal.

In the embodiment of the present invention, the STP in the MSC POOL stores the PRN message sent by the HLR to the backup MSC of the called terminal, and parses the location update request carried in the location update request when receiving the location update request sent by the MSC receiving the paging response of the called terminal. The specific extended cell is informed that the PRN message needs to be resent, and the stored PRN message is sent to the MSC that receives the paging response of the called terminal, so that the MSRN is obtained on the MSC after the location of the called terminal is updated, and the faulty MSC is implemented. Terminal, called for the first time The HLR can obtain the MSRN of the called terminal, thereby realizing the successful call of the terminal when the terminal is called for the first time, and saving the time required for the call to succeed when the terminal is called as the called terminal.

Finally, two systems for recovery of the called party in the MSC POOL according to the embodiment of the present invention are introduced.

The system for recovering a called party in the first MSC POOL according to the embodiment of the present invention includes:

The backup MSC of the called terminal is configured to obtain the MSRN allocated by the MSC that receives the paging response of the called terminal after the location update to the HLR, and the MSRN is carried in the PRN response message to the HLR.

The MSC receiving the paging response of the called terminal is configured to receive a paging response of the called terminal, and allocate an MSRN to the called terminal.

In the first embodiment of the present invention, the system in which the called MSC POOL recovers, the backup MSC of the called terminal acquires the MSRN that receives the paging response of the called terminal as the MSRN allocated by the called terminal, and the MSRN of the called terminal, The bearer is sent to the HLR in the PRN response message, and the terminal under the faulty MSC is realized. When the called party is called for the first time, the HLR can obtain the MSRN of the called terminal, thereby realizing the call when the terminal makes the called for the first time. Success, saves the time required for the call to succeed when the terminal under the MSC is called.

The first MSC provided by the embodiment of the present invention can be used as the implementation manner of the backup MSC of the called terminal. In the above system, the backup MSC of the called terminal may be the same as or different from the MSC receiving the paging response of the called terminal.

A system for recovering a called party in the second MSC POOL according to the embodiment of the present invention includes:

The MSC that receives the paging response of the called terminal is configured to notify the retransmission of the PRN message when performing location update to the HLR through the STP; receive the retransmitted PRN message, and carry the MSRN allocated to the called terminal in the PRN response message, HLR sends.

The STP is configured to connect, when the location is updated, the interaction between the MSC that receives the paging response of the called terminal and the HLR.

The HLR is configured to receive the PRN response message that is sent by the MSC that receives the paging response of the called terminal and that is the MSRN that is allocated to the called terminal. In the second embodiment of the present invention, when the MSC that receives the paging response of the called terminal performs location update to the HLR, it notifies the retransmission of the PRN message, that is, the notification to the receiving terminal that the paging response is received. The MSC resends the PRN message, so that the HLR can acquire the newly allocated MSRN for the called terminal from the MSC that receives the paging response of the called terminal, and implement the terminal under the faulty MSC. When the first call is made, the HLR The MSRN of the called terminal can be obtained, thereby realizing the successful call of the terminal when the terminal is called for the first time, and saving the time required for the call to succeed when the terminal under the faulty MSC is called.

The retransmitted PRN message received by the MSC receiving the paging response of the called terminal may be sent by the HLR; or may be sent by the STP, and the retransmitted PRN message is stored by the STP. The PRN message sent by the HLR to the backup MSC of the called terminal.

The second MSC provided by the implementation of the present invention may be used as the implementation manner of the MSC that receives the paging response of the called terminal. The STP provided by the embodiment of the present invention may be used as the implementation manner of the STP in the foregoing system. The HLR can be implemented as an implementation of the HLR in the above system.

Through the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be implemented by means of software plus necessary general hardware, and of course, by hardware, but in many cases, the former is a better implementation. . Based on such understanding, the technical solution of the present invention, which is essential or contributes to the prior art, may be embodied in the form of a software product stored in a readable storage medium, such as a floppy disk of a computer. A hard disk or optical disk or the like includes instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform the methods described in various embodiments of the present invention.

In conclusion, the above is only an embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A method for recovering a called party in a mobile switching center pool, the method comprising: receiving a roaming number message sent by a home location register;

2. The method according to claim 1, wherein the backup mobile switching center of the called terminal is a centralized backup mobile switching center; and the acquiring the roaming number assigned to the called terminal is: receiving the receiving The called terminal sends a private message sent by the mobile switching center in response to the paging, and the private message carries the roaming number assigned by the mobile switching center that receives the paging response of the called terminal to the called terminal.

The method according to claim 1, wherein the inter-domain non-access stratum node selection cell in the paging response includes a temporary mobile user allocated by the active mobile switching center corresponding to the called terminal. Identifier;

The obtaining the roaming number assigned to the called terminal is:

Receiving, by the mobile switching center that receives the paging response, the private message sent after the backup mobile switching center of the called terminal is found according to the temporary mobile subscriber identity code included in the paging response, where the private message carries The mobile switching center receiving the paging response is a roaming number assigned by the called terminal.

The method according to claim 1, wherein the inter-domain non-access stratum node selection cell in the paging response includes an international mobile subscriber identity of the called terminal;

Before the acquiring the roaming number assigned to the called terminal, the method further includes:

The access network searches for the correspondence between the international mobile subscriber identity and the mobile switching center according to the international mobile subscriber identity in the paging response, and determines the backup mobile switching center of the called terminal, which will be called The paging response of the terminal is sent to the backup mobile switching center of the called terminal, and the backup mobile switching center of the called terminal acts as a mobile switching center that receives the paging response of the called terminal;

The acquiring the roaming number assigned to the called terminal is: the backup mobile switching center of the called terminal, and acquiring the roaming number that is allocated by the called terminal.

The access network searches for the correspondence between the international mobile subscriber identity and the mobile switching center according to the international mobile subscriber identity in the paging response, determines the backup mobile switching center of the called terminal, and sends the called terminal paging response to the called terminal. a backup mobile switching center of the called terminal;

The backup mobile switching center of the called terminal redirects the paging response message to other mobile switching centers in the pool of the mobile switching center according to the load balancing algorithm, and the other mobile switching centers serve as paging responses for receiving the called terminal. Mobile switching center;

The roaming number assigned to the called terminal is: the backup mobile switching center of the called terminal, receiving the private message sent by the mobile switching center that receives the paging response of the called terminal, and the private message carries the receiving The roaming number assigned to the called terminal by the mobile switching center of the called terminal paging response.

A method for recovering a called party in a mobile switching center pool, the method comprising: receiving a paging response of a called terminal, and performing location update to a home location register by using a signaling transfer point, Notifying the home location register to resend the roaming number message;

Receiving a roaming number message retransmitted by the home location register;

The roaming number assigned to the called terminal;

The roaming number is carried in the providing roaming number response message and sent to the home location register.

7. The method of claim 6, wherein the home location register resends the roaming number message to provide:

Carrying an indication in the location update request sent to the home location register through the signaling transfer point Send a specific extension cell that provides a roaming number message.

8. The method according to claim 7, wherein the specific extension cell is: in the extended container field of the location update request message, filling in the content indicating to resend the message providing the roaming number, forming the specific extension Cell.

9. The method according to claim 7, wherein the method further comprises: after receiving the location update request, parsing the home location register, before receiving the roaming number message retransmitted by the home location register Specific extension cell;

The mobile switching center receiving the paging response of the called terminal receives the retransmitted provided roaming number message, and the home location register is retransmitted through the signaling transfer point.

The method according to claim 7, wherein the location update request sent to the home location register by the signaling transfer point comprises:

The signaling transfer point parses the specific extended cell in the location update request, and sends a location update request after deleting the specific extended cell to the home location register;

The mobile switching center that receives the paging response of the called terminal receives the re-sent roaming number providing message: receiving the providing roaming number message sent by the signaling transfer point, where the providing roaming number message is a signaling transfer point The stored home location register provides a roaming number message to the backup mobile switching center of the called terminal.

11. A mobile switching center in a pool of mobile switching centers, characterized in that the mobile switching center comprises:

a processing module, configured to acquire a roaming number assigned to the called terminal after the mobile switching center receiving the paging response of the called terminal performs location update to the home location register;

And a sending module, configured to send the roaming number of the called terminal in the processing module to the home location register by providing a roaming number response message.

12. The mobile switching center according to claim 11, wherein the mobile switching center is a mobile switching center that receives a paging response of the called terminal;

The processing module includes: a receiving module, an allocating module, and an obtaining module; The receiving module is configured to receive a paging response of the called terminal;

The allocating module is configured to allocate a roaming number to the called terminal;

The obtaining module is configured to obtain a roaming number that is allocated by the allocating module to the called terminal.

The MSC according to claim 11, wherein the processing module comprises: a receiving module, a redirection module, and an obtaining module;

The receiving module is configured to receive a paging response of the called terminal, and receive the private message sent by the mobile switching center that receives the paging response of the called terminal, where the private message carries the paging response of receiving the called terminal The roaming number assigned by the mobile switching center to the called terminal;

The redirection module is configured to redirect, according to a load balancing algorithm, a called terminal paging response received by the receiving module to another mobile switching center in a pool of a mobile switching center, where the other mobile switching centers are received as a mobile switching center called a terminal paging response;

The acquiring module is configured to obtain, from the private message received by the receiving module, a roaming number allocated by the mobile switching center that receives the paging response of the called terminal to the called terminal.

14. A mobile switching center in a pool of mobile switching centers, characterized in that the mobile switching center comprises:

a processing module, configured to receive a paging response of the called terminal; notify a resend to provide a roaming number message when the location is updated by the signaling transfer point to the home location register; assign a roaming number to the called terminal; and receive and receive a module for receiving Resending the provided roaming number message; the roaming number assigned by the processing module to the called terminal is carried in the providing roaming number response message to the home location register.

The mobile switching center according to claim 14, wherein the processing module comprises: a cell expansion module and a processing execution module;

The cell expansion module is configured to provide the process execution module with a specific extension cell that is instructed to resend the roaming number message;

The processing execution module is configured to receive a paging response of the called terminal; when performing location update to the home location register by using the signaling transfer point, carrying the specific extended cell provided by the cell expansion module in the location update request , the notification resends the provisioning roaming number message; assigns the roaming number to the called terminal.

16. A home location register in a pool of mobile switching centers, wherein the home location register comprises:

a location update processing module, configured to parse the mobile switching center that receives the paging response of the called terminal, in the sent location update request, carrying the indication to resend the specific extended cell that provides the roaming number message; and the message processing module is configured to Determining, by the location update processing module, the result of the parsing of the specific extended cell, disassembling the roaming number message sent to the backup mobile switching center of the called terminal, and paging the receiving called terminal through the signaling transfer point Responsive mobile switching center, resending the providing roaming number message; receiving the providing roaming number response message returned by the mobile switching center receiving the paging response of the called terminal, and obtaining the called terminal in the response message provided by the providing roaming number The assigned roaming number.

A signaling switching point in a mobile switching center pool, wherein the signaling switching point comprises: a parsing module, configured to parse a location of a mobile switching center that receives a paging response of a called terminal at a sending location In the request, the carried indication resends the specific extended cell that provides the roaming number message;

a message processing module, configured to receive a roaming number message sent by the home location register to the backup mobile switching center of the called terminal, and store the message; according to the parsing result of the specific extension cell by the parsing module, the specific extension is deleted The location update request of the cell is sent to the home location register; the stored provided roaming number message is sent to the mobile switching center that receives the paging response of the called terminal.

18. A system for recovering a called call in a pool of a mobile switching center, the system comprising: a backup mobile switching center of the called terminal, configured to acquire a mobile switching center that receives a paging response of the called terminal in a home location After the location update of the register, the roaming number assigned to the called terminal is carried in the providing roaming number response message to the home location register;

The mobile switching center receiving the paging response of the called terminal is configured to receive a paging response of the called terminal, and allocate a roaming number to the called terminal.

The system according to claim 18, wherein the backup mobile switching center of the called terminal and the mobile switching center that receives the paging response of the called terminal are the same mobile switching center, including: a receiving module , an allocation module and an acquisition module; The receiving module is configured to receive a paging response of the called terminal;

The system according to claim 18, wherein the backup mobile switching center of the called terminal and the mobile switching center that receives the paging response of the called terminal are different mobile switching centers; The backup mobile switching center of the terminal includes: a receiving module, a redirection module, and an obtaining module; the receiving module is configured to receive a paging response of the called terminal; and receive the private sent by the mobile switching center that receives the paging response of the called terminal a message, the private message carrying the roaming number assigned by the mobile switching center receiving the paging response of the called terminal to the called terminal;

A system for recovering a called call in a pool of a mobile switching center, the system comprising: a mobile switching center receiving a paging response of a called terminal, configured to perform location update to a home location register by using a signaling transfer point Receiving a re-send roaming number message; receiving a re-send roaming number message, carrying the roaming number assigned to the called terminal in the providing roaming number response message, and transmitting to the home location register;

a signaling transfer point, configured to, when the location is updated, connect the mobile switching center that receives the paging response of the called terminal to the home location register;

And a home location register, configured to receive the provided roaming number response message that is returned by the mobile switching center that receives the paging response of the called terminal, and that is the roaming number assigned to the called terminal, and obtain the roaming number assigned to the called terminal.

The system according to claim 21, wherein the resent providing roaming number message received by the mobile switching center receiving the paging response of the called terminal is sent by the home location The sender sent.

The system according to claim 21, wherein the resent providing roaming number message received by the mobile switching center receiving the paging response of the called terminal is sent by the signaling transfer point. And the resending providing roaming number message, providing a roaming number message sent by the home location register stored by the signaling transfer point to the backup mobile switching center of the called terminal.

24. A computer program product, comprising: computer program code, when said computer program code is executed by a computer, said computer program code causing said computer to perform claim 1 Steps in any of 5 or 6 to 10.

25. A computer readable storage medium, characterized in that the computer stores computer program code, and when the computer program code is executed by a computer, the computer program code can cause the computer to execute claim 1 Steps in any of 5 or 6 to 10.