CN1258935C - Disaster Tolerance Method for Mobile Softswitch Network - Google Patents

Abstract

The invention discloses a disaster recovery method for a mobile softswitch network. The redundant mechanism is used to back up the MSC Server network elements in the PLMN network system, so that the position and function of the network elements in the network are no longer unique, so as to improve the security of the network elements. Stability, and the purpose of further improving the stability of the entire network. When a major failure occurs on the MSC Server and it is difficult to recover for a while, the standby MSC Server will take over all users and process user services without interruption to achieve disaster recovery.

Description

Disaster Tolerance Method for Mobile Softswitch Network

technical field

The invention relates to mobile communication, in particular to a mobile softswitch network.

Background technique

The development of mobile communication technology enables mobile users to realize various services such as call service, short message service, and prepaid service through the operation of different network elements in the core network.

In the PLMN (Public Land Mobile Network, public land mobile network) network, the mobile user is in a certain location area, and the location area is under the jurisdiction of a certain RNC (Radio Network Controller, radio access network controller), and the RNC is controlled by a certain A MSC Server (Mobile Switching Center Server, mobile switching center server) jurisdiction. When a mobile user needs to perform a certain service, it needs to first access the core network through the access network, and then the MSC Server network element in the core network controls the call and other service signaling processes to complete the service expected by the user.

In the current network implementation, each network element is independent and unique. The users it manages and the functions it implements cannot be replaced by other network elements in the network. It will cause a large number of users to be unable to access the network for a long time.

Contents of the invention

The purpose of the present invention is to solve the problem that in the current network implementation, each network element is independent and unique, and the users and functions it manages cannot be replaced by other network elements in the network. Once a serious failure occurs in a certain network element, It cannot be restored in a short time, causing a large number of users to be unable to access the network for a long time.

For realizing the above-mentioned purpose of the invention, the present invention proposes the disaster tolerance method of mobile softswitch network, it is characterized in that, comprises the following steps:

1. Each RNC is connected to two or more (not including two) MSC Servers through MGW (Media Gate Way, Media Gateway);

2. Determine the corresponding relationship between the active MSC Server and other standby MSC Servers, including the following four schemes:

(1) MSC Server 1+1 active/standby scheme: MSC Servers connected to RNC include two, one is active and the other is standby, and the standby corresponds to the active one.

(2) MSC Server N+1 active/standby scheme: each RNC is connected to each corresponding active MSC Server, and the standby Servers of all active MSC Servers are the same MSC Server connected to all RNCs.

(3) The load sharing scheme of MSC Server: the MSC Server that links to each other with RNC comprises two, and one is active, and another one is standby, and for standby MSC Server, it is the active MSC Server of other RNC again.

(4) RNC selects the MSC Server scheme: the MSC Server connected to the RNC includes two or more than two (not including two), wherein only one is the main MSC Server, and the others are standby. For the standby MSC Server, it is also the active MSC Server of other RNCs.

3. Mutual switching between the active MSC Server and the standby MSC Server:

(1) For the MSC Server 1+1 active/standby scheme, when the active MSC Server works normally, the standby MSC Server does not work. When the active MSC Server goes down, the standby MSC Server becomes the active MSC Server to take over the RNC users, and after the original active MSC Server returns to normal, it becomes the standby MSC Server.

(2) For the MSC Server N+1 active/standby scheme, when the active MSC Server works normally, the standby MSC Server does not work. When the active MSC Server goes down, the users of the original RNC are taken over by the standby MSC Server, and when the active MSC Server returns to normal, all users switch back to the active MSC Server.

(3) For the load sharing scheme of MSC Server, when the active MSC Server connected to the RNC works normally, all users accessing through the RNC are handled by the active MSC Server. When the active MSC Server is abnormal, the MGW is handled by the standby MSC The Server takes over the control, and all users accessing through the RNC are handled by the standby MSC Server. When the active MSC Server returns to normal, the user switches back to the active MSC Server. The active MSC Server and the standby MSC Server are independent network elements, and they are mutually active and standby. The standby MSC Server is also the active MSC Server of other RNCs and works normally in the network.

(4) For the RNC to select the MSC Server scheme, when the active MSC Server connected to the RNC works normally, all users accessing through the RNC are processed by the active MSC Server. Select one of the Servers or select multiple standby MSC Servers for load sharing to handle the users connected to the RNC. When the active MSC Server returns to normal, the user switches back to the active MSC Server.

By adopting the disaster recovery method of the mobile softswitch network described in the present invention, when an abnormality occurs in an MSC Server, other MSC Servers (standby MSC Servers of the faulty MSC Server) can take over all users and can successfully process all services of such users. When the original faulty MSC Server resumes normal operation, the user's business can also be smoothly switched back to the original MSC Server. As a result, when MSC Server has a major failure and is difficult to recover for a while, it can normally process the business of the users it manages to achieve the purpose of disaster recovery.

Description of drawings

Fig. 1 is a flowchart of a disaster recovery method for a mobile softswitch network according to the present invention.

Fig. 2 is a structural diagram of the MSC Server 1+1 active/standby system of the present invention.

Fig. 3 is the structural diagram of MSC Server N+1 main backup system of the present invention.

Fig. 4 is a structural diagram of the MSC Server load sharing system of the present invention.

Fig. 5 is that RNC of the present invention selects MSC Server scheme system structural diagram.

Detailed ways

Fig. 1 is a flowchart of a disaster recovery method for a mobile softswitch network according to the present invention. Each RNC is connected to two or more (not including two) MSC Servers through the MGW;

Determine the corresponding relationship between the active MSC Server and other standby MSC Servers, including four schemes: MSC Server 1+1 active standby scheme, the MSC Server connected to the RNC includes two, one is active, the other is standby, and the standby and Master one-to-one correspondence; MSC ServerN+1 master-backup scheme, there are two MSC Servers connected to the RNC, only one of which is the master MSC Server, and one is the backup, and the backup Servers of all the master MSC Servers are the same MSC Server; the load sharing scheme of MSC Server, the MSC Server connected to the RNC includes two, one is active and the other is standby, and for the standby MSC Server, it is the active MSC Server of other RNCs; RNC chooses the MSC Server scheme: with The MSC Servers connected by the RNC include two or more than two (not including two), of which only one is the active MSC Server, and the others are standby. For the standby MSC Server, it is also the active MSC Server of other RNCs.

Mutual switching between the active MSC Server and the standby MSC Server: For the MSCServer 1+1 active-standby scheme, when the active MSC Server works normally, the standby MSC Server does not work. When the active MSC Server goes down, the standby MSC Server becomes the active MSC Server to take over the users of the RNC. After the original active MSC Server returns to normal, it becomes the standby MSC Server; for MSC Server N+1 active/standby scheme, the active MSC Server When working normally, the standby MSC Server does not work. When the active MSC Server goes down, the users of the original RNC will be taken over by the standby MSC Server. When the active MSC Server returns to normal, all users will switch back to the active MSC Server; When the MSC Server works normally, all users accessing through the RNC are handled by the active MSC Server. When the active MSC Server is abnormal, the MGW is taken over by the standby MSC Server, and all users accessing through the RNC are handled by the standby MSC Server. Processing, when the active MSC Server returns to normal, the user switches back to the active MSC Server. The active MSC Server and the standby MSC Server are independent network elements, and they are mutually active and standby. The standby MSC Server is also the active MSC Server of other RNCs, and works normally in the network; When the active MSC Server is working normally, all the users accessing through the RNC will be processed by the active MSC Server. When the active MSC Server is abnormal, the RNC will select one of the standby MSC Servers or select multiple standby MSC Servers for load sharing. Users accessed by the RNC. When the active MSC Server returns to normal, the user switches back to the active MSC Server.

Fig. 2 is a structural diagram of the MSC Server 1+1 active/standby system of the present invention. When the MSC Server is powered on and started, it first changes the status to standby, and then changes the status to active after receiving the registration message from the MGW. When the active MSC Server has abnormal conditions such as downtime, the MGW controlled by it re-registers with the standby MSC Server. After receiving the registration message from the MGW, the MSC Server modifies the status of the MSC Server to be active, and sends a Reset (reset) message to notify the RNC to release the MSC Server. resource.

In this scheme, the location update and access process are not affected, which is consistent with the normal process. Special processing is required for the called user. After HLR (Home Location Register, Home Location Register) receives the query routing request, it requests the roaming number from MSC Server. When the message selects a route on the STP (Signal Transfer Point) directly connected to the MSC server, if the link of the active server fails, a backup route is selected and sent to the backup MSC Server. After receiving the roaming number request message, the MSC Server performs a Restore (recovery) process to the HLR to obtain the user's data and provide the roaming number.

When the original active MSC Server returns to normal, power on again to start, change the status to standby, change to standby MSC Server, and stop working.

After the original master is changed to the new standby, the location update and outgoing calls will not be affected. For the called user whose VLR number in the HLR is still the original active VLR number, the method of updating the HLR can be used to restore the called ability. After HLR receives the inquiry routing request of GMSC (Gateway MSC, mobile switching center gateway), it requests roaming number to original active MSC Server. After the original main server receives the message, it checks and finds that it is in the standby state, then returns a maperror (mobile application part error) message to the HLR, and fails to provide the roaming number. Then send a location update request to the HLR, and the message carries the number of the new active VLR. After the HLR receives the message, it will update the VLR (Visitor Location Register, mobile location register) number in the HLR to be the new main VLR number, and send a Cancel Location (location deletion) message to the original main VLR at the same time, and insert a user data message. Regardless of whether the HLR update is successful, the VLR number in the HLR has been changed to the new primary VLR number. After the process of updating the HLR, the original master VLR actively invokes the database to delete the stored user information.

Fig. 3 is the structural diagram of MSC Server N+1 main backup system of the present invention. When the active MSC Server has abnormal conditions such as downtime, the MGW controlled by it re-registers with the standby MSC Server. After receiving the registration message from the MGW, the MSC Server modifies the status of the standby RNC and LAI to be active, and sends a Reset message to notify the RNC to release resource.

When the user accesses from the RNC, the SG (singnal gateway, signaling gateway) forwards it to the MSC Server for processing. After the MSC Server receives the message, it first checks whether the RNC is under the jurisdiction of the MSC Server in the active state RNC list, and if it is found, the user is allowed to access from the RNC. Then check whether the LAI is recognized in the active state LAI list. If found, it is considered that the user is allowed to access.

If the subscriber identity carried in the signaling is TMSI (Temporary Mobile Subscriber Identity, temporary subscriber identity), and the state of the MSC Server is the standby state, if the subscriber can be found according to the TMSI, in order to avoid that the subscriber may be a different subscriber with the same TMSI, The following three methods can be adopted: 1. It is necessary to obtain an IMSI (International Mobile Subscriber Identity) from the MS;

2. Authentication must be performed. If the authentication fails, it is necessary to obtain the IMSI from the MS and re-authenticate.

3. Determine whether to ask for IMSI from the MS by controlling the TMSI allocation method (for example, the active MSC Server allocates 0xxxxxxxxxxxxxxx, and the standby MSC Server allocates 1xxxxxxxxxxxxxxx; in this way, you can know whether it is allocated by yourself through the TMSI ID. If so, follow the The normal flow is processed, otherwise, the user identification process is initiated, and the MS asks for an IMSI). When there is no subscriber data in the standby MSC Server, how to obtain subscriber data can have the following two schemes: one, carry out the location update process of HLR, update the VLR number in the HLR to be standby VLR number, thereby obtain subscriber data. Two, if VLR finds that the state of MSC Server is standby state, then do not start the location update process, start the Restore process, obtain subscriber data, the VLR number in the HLR remains unchanged.

After the HLR receives the query routing request, it requests the roaming number from the MSC Server (VLR). When the message selects a route on the STP directly connected to the MSC server, if the link of the active server fails, a backup route is selected and sent to the backup MSC Server.

After receiving the roaming number request message, the MSC Server performs a Restore process to the HLR to obtain the user's data and provide the roaming number. MSC Server paging user, only send paging message to the RNC whose RNC state is active.

After the main MSC server returns to normal, the MGW disconnects from the standby MSC Server and re-registers with the main MSC Server. After receiving the disconnection message from the MGW, the standby MSC Server modifies the status of the standby RNC and LAI to standby. After the active MSC Server returns to normal, it sends a Reset message to the RNC to notify the RNC to release resources. The user switches back to the active MSC Server.

For the processing of location update or outgoing call, it is consistent with the standby MSC Server. In order to avoid different users with the same TMSI, mandatory authentication is also required.

For the called user, if the location is updated or the caller chooses not to update the HLR and starts the Restore process, the service will automatically switch back to the active MSC Server, and the called process will not be affected. If you choose to update the HLR, for the called user whose VLR number in the HLR is already the standby VLR number, consider using the method of updating the HLR to restore the called ability. When the HLR receives the routing request from the GMSC, it requests the roaming number from the standby MSC Server. After the standby MSCServer receives the message, after finding the user information, check whether the LAI state of the user is a standby state, if so, return a map error message to the HLR, and provide a roaming number failure. Then send a location update request to the HLR, and the message carries the active VLR number. After the HLR receives the message, it will update the VLR number in the HLR as the active VLR number, and at the same time send a Cancel Location message to the backup VLR and insert a user data message. Regardless of whether the HLR update is successful, the VLR number in the HLR has been changed to the active VLR number. After the process of updating the HLR is completed, the standby VLR actively invokes the database to delete the stored user information.

Fig. 4 is a structural diagram of the MSC Server load sharing system of the present invention. When the active MSC Server has abnormal conditions such as downtime, the MGW controlled by it re-registers with the standby MSC Server. After receiving the registration message from the MGW, the MSC Server modifies the status of the standby RNC and LAI (Location Area Identity) to standby Change to active use, and send a Reset message to notify the RNC to release resources.

When the user accesses from the RNC, the SG is forwarded to the MSC Server for processing. After the MSC Server receives the message, it calls the database, checks whether the RNC is under the jurisdiction of the MSC Server in the active state RNC list and the standby-to-active state RNC list, and if found, allows the user to access from the RNC and then from the active state. The state LAI list and the standby-to-active state LAI list are searched. If found, it is considered that the user is allowed to access.

If the user ID carried in the signaling is TMSI, and the MSC Server is in the standby state, if the user can be found according to the TMSI, in order to avoid the situation that the user may be a different user with the same TMSI, the processing can refer to the processing of N+1 backup .

When there is no user data in the standby MSC Server, how to obtain user data can refer to the processing of N+1 backup.

After the HLR receives the query routing request, it requests the roaming number from the MSC Server. When the message is selected on the STP directly connected to the MSC Server, if the link of the active Server is unreachable, the backup route will be selected and sent to the backup MSC Server.

After receiving the roaming number request message, the MSC Server performs a Restore process to the HLR to obtain the user's data. And provide roaming numbers.

MSC Server paging users, only send paging messages to the RNC whose RNC status is master and backup to master.

After the main MSC server returns to normal, the MGW disconnects from the standby MSC Server and re-registers with the main MSC Server. After receiving the disconnection message from the MGW, the standby MSC Server modifies the status of the standby RNC and LAI to standby. After the active MSC Server returns to normal, it sends a Reset message to the RNC to notify the RNC to release resources. The user switches back to the active MSC Server.

The processing of location update or outgoing calls is consistent with that of the standby MSC Server. For the processing of the called party, refer to the processing of N+1 backup.

Fig. 5 is that RNC of the present invention selects MSC Server scheme system structural diagram. The RNC can select the MSC Server mode in the following three ways. Method 1: Select a standby MSC Server to handle all RNC users according to priority; Method 2: Select different MSC Servers to handle different RNC users according to the LAI to which users belong; Method 3: Select different MSC Servers according to the principle of patrolling Handle different users of the RNC. When the active MSC Server of the RNC goes down, the link between the RNC and the active MSC Server is completely interrupted, and the signaling point is unreachable.

If the RNC selects the MSC Server mode as method one, then the RNC selects a MSC Server with the highest priority that works normally (the signaling point is reachable) from the list of standby MSC Servers, and its state is changed from standby to active state. RNC sends a Reset message to the newly taken-over MSC Server, and after receiving the message, the MSC Server changes the status of RNC and LAI from standby to active. When a user accesses from the RNC, select the MSC Server whose status is standby to master to handle all users.

If the RNC selects the MSC Server mode as method two, then the RNC selects the MSC Servers that work normally from the list of standby MSC Servers, distributes the LAI under the jurisdiction of the RNC to these Servers, records the correspondence between the LAI and the Servers, and sends a Reset message to notify these MSC Server changes the status of RNC and LAI from standby to active. When the user accesses, select the MSC Server according to the corresponding relationship table between LAI and Server.

If the RNC selects the MSC Server mode as method three, it sends a Reset message to notify all standby MSC Servers to change the state of RNC and LAI from standby to active. When a user accesses from the RNC, a specific MSC Server is selected to process the user according to the patrolling principle.

The implementation of location update or access process is the same as that of MSC Server load sharing scheme. Select to update the information in the HLR.

After the HLR receives the query routing request, it requests the roaming number from the MSC Server (VLR). When the message selects a route on the STP directly connected to the MSC server, if the link of the active server fails, a backup route is selected and sent to the backup MSC Server.

After receiving the roaming number request message, the MSC Server performs a Restore process to the HLR to obtain the user's data. And provide roaming number.

MSC Server paging users, only send paging messages to the RNC whose RNC status is master and backup to master.

After the RNC receives the paging message, it needs to record the paged user and the MSC Server identification that sends the paging, so that when receiving a paging response or location update or an outgoing call request, it selects the MSC Server that sends the paging to process.

After the active MSC Server returns to normal, it sends a Reset message to notify the RNC, and the MSC Server resumes normal work. After the RNC receives the Reset message, it changes the state of the MSC Server from the standby to the active state to standby. Subsequent users accessing through the RNC are still normally processed by its primary MSC Server.

The processing of location update or outgoing calls is consistent with that of the standby MSC Server.

For the called subscriber whose VLR number in the HLR is already the standby VLR number, since the standby MSC Server cannot obtain whether the active MSC Server is back to normal, the state of the RNC and LAI from the standby to the active one cannot be modified, so it is considered that such users are still temporarily It is handled by the standby MSC Server until such users modify the VLR number in the HLR after performing location update through the RNC. Standby MSC Server sends the paging message, after RNC receives it, if it is from the standby MSC Server, it will record the user being paged and the MSC Server ID that sent the paging, so that when it receives a paging response or location update or calls out When requesting, select the MSC Server that sends the paging to process.

When this type of user performs normal location update through the RNC, the VLR number in the HLR will be modified as the primary VLR number, and the HLR will send a Cancel Location message to the backup MSC Server, and the backup MSC Server will delete the user data at this time. The users in the VLR can be formed into a linked list according to the LAI, mainly the LAI whose state is changed from standby to active. After the standby MSC Server deletes the user whose LAI status is standby to master, check the list, and if the linked list is empty, then modify the status of the LAI to standby. When the states of all LAIs under the RNC are changed from the standby state to the active state to the standby state, the state of the RNC is changed to the standby state.

Claims (14)

1. A disaster recovery method for a mobile softswitch network, comprising the following steps: (1) Each radio access network controller is connected to two or more mobile switching center servers through a media gateway; (2) Determine the corresponding relationship between the active mobile switching center server and other standby mobile switching center servers; (3) Mutual switching between the active mobile switching center server and the standby mobile switching center server. 2, the disaster recovery method of mobile softswitch network as claimed in claim 1 is characterized in that, described in the step (2), the corresponding relationship between the active mobile switching center server and other standby mobile switching center servers is, and wireless The mobile switching center server connected to the access network controller includes two servers, one active and the other standby, and the standby mobile switching center server corresponds to the active mobile switching center server one by one. 3, the disaster recovery method of mobile softswitch network as claimed in claim 1 is characterized in that, described in the step (2), the corresponding relationship between the active mobile switching center server and other standby mobile switching center servers is that each The radio access network controllers are respectively connected to a corresponding active mobile switching center server, and the standby mobile switching center servers of all active mobile switching center servers are the same mobile switching center connected to all radio access network controllers server. 4. The disaster recovery method of mobile softswitch network as claimed in claim 1, characterized in that, the corresponding relationship between the active mobile switching center server and other backup mobile switching center servers described in step (2) is, and wireless The mobile switching center server connected to the access network controller includes two, one is the active mobile switching center server, and the other is the standby mobile switching center server, and the standby mobile switching center server is another wireless access network controller The primary mobile switching center server. 5. The disaster recovery method of mobile softswitch network as claimed in claim 1, characterized in that, the corresponding relationship between the active mobile switching center server and other backup mobile switching center servers described in step (2) is, and wireless The mobile switching center server connected to the access network controller includes more than two, but does not include two, and only one of them is the active mobile switching center server, and the others are standby. For other standby mobile switching center servers, they are other wireless The active mobile switching center server of the access network controller. 6. The disaster recovery method of mobile softswitch network as claimed in claim 1, characterized in that, the method for switching between the main mobile switching center server and the standby mobile switching center server described in step (3) is that the main mobile switching center server When the mobile switching center server works normally, the backup mobile switching center server does not work; when the main mobile switching center server goes down, the backup mobile switching center server becomes the main mobile switching center server to take over the user of the radio access network controller; After the original active mobile switching center server returns to normal, it is transformed into a standby mobile switching center server. 7. The disaster recovery method of mobile softswitch network as claimed in claim 1, characterized in that, the method for switching between the main mobile switching center server and the backup mobile switching center server described in step (3) is that the main mobile switching center server When the main mobile switching center server works normally, the backup mobile switching center server does not work; when the main mobile switching center server goes down, the users of the original radio access network controller are taken over by the backup mobile switching center server; when the main mobile switching center server After returning to normal, switch back to the active mobile switching center server. 8. The disaster recovery method of mobile softswitch network as claimed in claim 1, characterized in that, the method for switching between the active mobile switching center server and the backup mobile switching center server described in step (3) is that when When the active mobile switching center server connected to the wireless access network controller is working normally, all users accessing through the wireless access network controller are processed by the active mobile switching center server; when the active mobile switching center server is abnormal , the media gateway is taken over and controlled by the standby mobile switching center server, and all users accessing through the radio access network controller are handled by the standby mobile switching center server; when the active mobile switching center server returns to normal, the user switches back to the active mobile switching center central server. 9. The disaster recovery method of mobile softswitch network as claimed in claim 1, characterized in that, the method for switching between the active mobile switching center server and the backup mobile switching center server described in step (3) is that when When the active mobile switching center server connected to the wireless access network controller is working normally, all users accessing through the wireless access network controller are processed by the active mobile switching center server; when the active mobile switching center server is abnormal , the radio access network controller selects one of the standby mobile switching center servers or selects multiple standby mobile switching center servers for load sharing to handle the users accessed by the radio access network controller; when the active mobile switching center server returns to normal , the user switches back to the active mobile switching center server. 10. The disaster recovery method of the mobile softswitch network according to claim 7 or 8, characterized in that, during the takeover process of the standby mobile switching center server, when there is no user data in the standby mobile switching center server, the user data is obtained The method is to perform the location update process of the HLR, and update the MLR number in the HLR to be the spare MLR number, thereby obtaining user data. 11. The disaster recovery method of the mobile softswitch network as claimed in claim 7 or 8, characterized in that, during the takeover process of the standby mobile switching center server, when there is no user data in the standby mobile switching center server, the user data is obtained The method is that if the mobile location register finds that the state of the mobile switching center server is standby, the location update process is not started, but the recovery process is started to obtain user data, and the mobile location register number in the home location register remains unchanged. 12. The method for disaster recovery of a mobile softswitch network according to claim 9, wherein the radio access network controller selects one of the backup mobile switching center servers or load sharing selects a plurality of backup mobile switching center servers The method is to select a backup mobile switching center server according to priority to handle all users of the radio access network controller, that is, the radio access network controller selects a normal mobile switching center server with the highest priority from the list of backup mobile switching center servers The switching center server changes its state from standby to active state; the radio access network controller sends a reset message to the newly taken over mobile switching center server, and after receiving the message, the mobile switching center server switches the radio access network controller, The status of the location area identification is changed from standby to active; when a user accesses from the radio access network controller, the mobile switching center server whose status is standby to active is selected to process all users. 13. The method for disaster recovery of a mobile softswitch network according to claim 9, wherein the radio access network controller selects one of the backup mobile switching center servers or load sharing selects a plurality of backup mobile switching center servers The method is to select different mobile switching center servers to handle different users of the radio access network controller according to the location area identifier to which the user belongs, that is, the radio access network controller selects the normal mobile switching center server from the backup mobile switching center server list The central server assigns the location area identifiers under the jurisdiction of the wireless access network controller to these mobile switching center servers, records the corresponding relationship between the location area identifiers and the mobile switching center servers, and sends a reset message to notify these mobile switching center servers The state of the network access controller and the location area identifier is changed from standby to active; when the user accesses, the mobile switching center server is selected according to the corresponding relationship table between the location area identifier and the mobile switching center server. 14. The method for disaster recovery of a mobile softswitch network according to claim 9, wherein the radio access network controller selects one of the backup mobile switching center servers or load sharing selects a plurality of backup mobile switching center servers The best method is to select different mobile switching center servers to handle different users of radio access network controllers according to the principle of round-robin, that is, to send a reset message to notify all standby mobile switching center servers to reset radio access network controllers, location area The identification status is changed from standby to active; when a user accesses from the radio access network controller, a specific mobile switching center server is selected to process the user according to the principle of round-robin.

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