CN101902824B - Local switch implementation method, mobile switch centre and communication system - Google Patents

Abstract

The invention discloses a method for realizing local switching, a mobile switching center and a communication system. In the embodiment of the present invention, when both calling parties are in the first mobile switching center and the second mobile switching center, the first mobile switching center where the first calling party is located obtains the local switching information of the second calling party sent by the second mobile switching center , and then perform local switching processing according to the local switching information of the first calling party and the local switching information of the second calling party, wherein the local switching information of the first calling party or the local switching information of the second calling party include corresponding call In the MSC POOL network, even if the calling party and the called party are located on different MSCs, the calling party or the called party can also know the BSC where the other party is calling, and can judge whether to start local switching for local exchange processing.

Description

A method for implementing local switching, a mobile switching center and a communication system

technical field

The invention relates to the technical field of communication, in particular to a method for realizing local switching, a mobile switching center and a communication system.

Background technique

The transmission network is an important part of the wireless communication network. Reducing the occupation of transmission network resources (hereinafter referred to as transmission resources) is conducive to reducing the cost of network construction and operation. Local switching is an effective solution to reduce the occupation of transmission resources.

Local switching refers to the conversation in which the calling party and the called party are located in the same Base Station Subsystem (BSS, BaseStation Subsystem), the loopback of the voice link is completed in the BSS, that is, the voice data of the user plane does not flow out of the BSS, thereby A technical solution for saving transmission resources of a specific interface. Local switching can be divided into local switching in a base station (BTS, Base Transceiver Station) and local switching in a base station controller (BSC, Base Station Controller). Wherein, the local switching in the base station refers to that the two conversation parties are located in the same base station, or in the same base station cluster (for the case of cascaded base stations), and the loopback of the voice link occurs in the corresponding base station. The local switching in the base station controller means that the two parties in the conversation are located in the same base station controller, but in different base stations (or base station clusters), and the voice link loopback occurs in the corresponding base station controller. By establishing local switching in the base station, it is possible to realize the connection between Abis (the interface between the base station and the base station controller), Ater (the interface between the base station and the base station controller), and the A port (BSS and the mobile switching center (MSC, Mobile Switch Center) ) transmission resources of the interface between ) can be saved, and the transmission resources of the A interface can be saved by establishing a local switch in the base station controller.

The prior art defines the implementation method of local switching in a non-MSC pool (POOL) network, mainly through the MSC to judge whether the base station controllers where the calling party and the called party are located in the same MSC belong to the same base station controller, and whether they have The conditions for starting local switching are used to determine whether to start local switching. If the calling party and the called party belong to the same base station controller and meet the conditions for starting local switching, the MSC sends an instruction to start local switching to the base station controller, and the base station controller executes the establishment of local switching. swap operation. After the MSC receives the local switching establishment completion message from the base station controller, it releases the A-port circuit resources used by the calling and called users. Among them, the conditions for initiating local switching refer to the fact that in the absence of supplementary services, announcements, or legal interception operations, if after local switching is activated, supplementary services, announcements, or legal interception operations occur, or In the event that the calling and called base station controllers no longer belong to the same base station controller due to handover, the local switching needs to be released. At this time, the MSC can request the base station controller to release the local switching by sending a signaling.

During the research and practice of the prior art, the inventors of the present invention found that there is no relevant solution in the prior art for realizing local switching under the MSCPOOL network.

Contents of the invention

Embodiments of the present invention provide a method for realizing local switching, a mobile switching center and a communication system, which can realize local switching under the MSC POOL network.

A method for implementing local switching, characterized by comprising:

When both calling parties are in the first mobile switching center and the second mobile switching center respectively, the first mobile switching center where the first calling party is located obtains the local switching information of the second calling party sent by the second mobile switching center;

The first mobile switching center performs local switching processing according to the local switching information of the first calling party and the local switching information of the second calling party, wherein the local switching information of the first calling party or the local switching information of the second calling party are respectively Contains information about the base station controller where the corresponding calling party is located.

A mobile switching center, characterized in that it comprises:

An acquisition unit, configured to acquire the local switching information of the second calling party sent by the second mobile switching center when both calling parties are in the first mobile switching center and the second mobile switching center respectively;

A processing unit, configured to perform local switching processing according to the local switching information of the first calling party and the local switching information of the second calling party, wherein the local switching information of the first calling party or the local switching information of the second calling party The local switching information respectively includes the information of the base station controller where the corresponding calling party is located.

A communication system, characterized by comprising a first mobile switching center and a second mobile switching center;

The first mobile switching center is configured to acquire the local switching information of the second calling party sent by the second mobile switching center when both calling parties are in the first mobile switching center and the second mobile switching center, according to the first The local switching information of the calling party and the local switching information of the second calling party are processed for local switching, wherein the local switching information of the first calling party or the local switching information of the second calling party respectively include corresponding calling party Information about the base station controller where it is located;

The second mobile switching center is configured to send local switching information of the local party to the first mobile switching center.

The embodiment of the present invention adopts the local exchange information of the other party sent by the MSC that receives the call of the other party, and then performs local exchange processing according to the local exchange information of the party and the local exchange information of the other party, so that under the MSC POOL network, even if the calling party and the called party They are respectively located on different MSCs, and the calling party or the called party can also know the BSC where the other party is calling, and can make a judgment to start local switching so as to perform local switching processing.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained based on these drawings without creative effort.

Fig. 1 is a method flowchart of the method provided by Embodiment 1 of the present invention;

Fig. 2 is a method flowchart of the method provided by Embodiment 2 of the present invention;

Fig. 3 is another method flowchart of the method provided by Embodiment 2 of the present invention;

Fig. 4 is another method flowchart of the method provided by Embodiment 2 of the present invention;

Fig. 5 is a method flow chart of the method provided by Embodiment 3 of the present invention;

Fig. 6 is another method flowchart of the method provided by Embodiment 3 of the present invention;

Fig. 7 is another method flowchart of the method provided by Embodiment 3 of the present invention;

FIG. 8 is a schematic structural diagram of a mobile switching center provided by an embodiment of the present invention;

Fig. 9 is a schematic structural diagram of a communication system provided by an embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

In the MSC POOL network, since the calling party and the called party may be located in the same base station controller but located in different MSCs, the MSCs where the calling party and the called party are located cannot know the base station controller where the other party is calling, so it is impossible to start local switching. judgment. Moreover, if a call is monitored on one of the MSCs, or the local exchange cannot be started when performing operations such as announcement or supplementary services, the other MSC cannot know. In order to realize local switching under the MSC POOL network, the embodiment of the present invention provides a method for implementing local switching, and also provides a corresponding mobile switching center and communication system. Each will be described in detail below.

Embodiment one,

This embodiment will be described from the perspective of a mobile switching center, ie MSC. It should be noted that the "own party" and "other party" mentioned in the embodiment of the present invention are for calling. For example, from the calling point of view, the calling party is "the party" and the called party is " From the perspective of the called party, the called party is the "own party" and the calling party is the "other party". In the embodiment of the present invention, the mobile switching center of the party is called the first mobile switching center, and the mobile switching center of the other party is called the second mobile switching center. Therefore, the first and second mobile switching centers can be the calling party's mobile switching center. The center can also be the mobile switching center of the called party. When the first mobile switching center is the mobile switching center of the calling party, the second mobile switching center is the mobile switching center of the called party. When the first mobile switching center is the mobile switching center of the called party When the mobile switching center of the calling party is used, the second mobile switching center is the mobile switching center of the calling party. The scheme is as follows:

A method for realizing local switching, comprising: when both calling parties are in the first mobile switching center and the second mobile switching center, the first mobile switching center obtains the local switching information of the second mobile switching center, and according to the local switching The information and the local switching information of the second mobile switching center are processed by local switching. Since the MSCs of the calling party and the called party can exchange local exchange information, both parties can fully understand each other's local exchange information, so it can be performed according to the complete local exchange information (including the local exchange information of the calling party and the called party). Handling of local exchanges. As shown in Figure 1, the specific process can be as follows:

101. The first mobile switching center acquires the local switching information of the other party sent by the second mobile switching center;

For example, the local switching information of the other party sent by the other party's MSC can be obtained through the mobile application part (MAP, Mobile Application Part) signaling or relay signaling, wherein the local switching information can include base station controller signaling point information, and can also include The local switching capability information of the other party, of course, also includes other information needed to establish or release the local switching, such as the Call-ID of the call or the bearer information of the A interface. Wherein, the base station controller signaling point information refers to one party's call leg (the so-called call leg refers to one party's call. For example, a call is composed of a calling party and a called party, and each party is called a calling leg.) The base station controller information of the first mobile switching center or the second mobile switching center can be the information of the base station controller signaling point where the calling party is located in the local office. According to the information of the base station controller signaling point, it can be determined Whether the BSCs are the same BSC or not, it is determined whether local switching needs to be performed according to the judgment result. The local switching capability information refers to whether the call is monitored, or whether it is performing operations such as playing a sound or supplementing services. According to the local switching capability information of the other party, it can be further judged whether the other party can perform local switching. Call-ID is used to identify the call information of the calling party and the called party. After the mobile switching center that performs local switching obtains the Call-ID of the other party, it provides the Call-ID of the party and the other party to the base station controller, so that the base station controls The router establishes a local exchange based on the Call-ID. The bearer information of the A port is used when the mobile switching center performing local switching releases the local switching.

If both the calling party and the called party provide local exchange information through MAP signaling (that is, bear the weight of local exchange information through MAP signaling), the address of the MSC called by the other party can be obtained, and then according to the obtained MSC of the other party address for MAP signaling, and use the International Mobile Subscriber Identity (IMSI, International Mobile Subscriber Identity) information to associate calls, so that in the subsequent execution process, the MSC can exchange information according to its local exchange information and the other party’s The local switching information performs local switching processing on the associated call. That is to say, before obtaining the local exchange information sent by the MSC called by the other party through MAP signaling, the address of the MSC called by the own party and the IMSI information of the called MSC can also be sent to the MSC called by the other party, and then the MSC called by the other party The MSC just can send the other party's local switching information to the MSC that the own party calls according to the address of the MSC that the own party calls, wherein, the IMSI information that the own party calls is carried in the local switching information of the other party, like this, the MSC that the own party calls receives After the local switching information of the other party, the call can be associated according to the IMSI information of the local call carried in the received local switching information of the other party, and then associated according to the local switching information of the local party and the local switching information of the other party Subsequent calls are processed by local switching.

102. The first mobile switching center performs local switching processing according to the local switching information of its own party and the local switching information of the second mobile switching center as the other party, including the processing of establishing local switching or the processing of canceling local switching, etc.;

For example, if it is determined according to the signaling point information of the base station controller called by the own party and the signaling point information of the base station controller called by the other party, it is determined that the calls of both parties belong to the same base station controller, notify the base station controller to start local switching, and notify the mobile gateway to release the local switching. In addition, if the local switching information also includes the local switching capability, the first mobile switching center can continue to judge, that is, determine whether both parties have When the local switching capability is enabled, the base station controller is notified to start local switching when the judgment result is yes, and the mobile gateway is notified to release the local A port resources; if the local switching information does not include the local switching capability, in order to ensure the local switching Correct implementation, before the second mobile switching center provides local switching information to the first mobile switching center, it can first judge whether it has local switching capability, and if so, it provides local switching information to the first mobile switching center, and the first mobile switching center Before acquiring the local switching information of the second mobile switching center or processing the local switching, the switching center can judge whether it has the local switching capability, and if so, perform corresponding operations. Of course, it is also possible to directly judge whether to perform local switching according to the signaling point information of the calling party and the called party, without considering the information of the local switching capability.

Wherein, after informing the mobile gateway to release the A port resources of the party, it can also send a local exchange establishment response message to the other party's MSC, so that the MSC called by the other party can notify the mobile gateway to release the other party's A port resources according to the local exchange establishment response message . That is to say, both the calling party and the called party can be allowed to judge and start the local switching respectively, or only one of them can be allowed to judge and start the local switching, and then notify the other party.

After the local switching is established, if it is necessary to cancel the local switching, for example, when it needs to be legally intercepted, or perform announcements or supplementary service operations, it can apply to the mobile gateway according to the local switching information of the local switching party and the local switching capability information of the other party. If the application for the resources of the A port of the party is successful, the local switching release request is sent to the MSC of the other party, so that the MSC called by the other party applies to the mobile gateway for the resources of the A port of the other party according to the local switching release request. After the MSC called by the other party returns an acknowledgment message indicating that it has successfully applied for the resource of the A port of the other party, it notifies the base station controller to release the local switching. It should be noted that after the other party's MSC successfully applies for the A port resource, it may also notify the base station controller to cancel the local switching, and then return a confirmation message indicating that the other party's A port resource has been successfully applied to the local MSC.

Or, after the local exchange is established, if it is necessary to cancel the local exchange, it is also possible to send a local exchange release request to the other party's MSC directly without applying for the A port resource of the own party, so that the MSC called by the other party can respond to the local exchange release request. Apply to the mobile gateway for the A port resource of the other party, and apply for the A port resource of the other party after receiving the confirmation message returned by the MSC called by the other party indicating that the A port resource of the other party has been successfully applied. If the application for the A port resource fails, then The local switching is not canceled, otherwise, if the application for A port resources is successful, the base station controller is notified to cancel the local switching.

As can be seen from the above, the present embodiment adopts the local exchange information of the other party sent by the MSC that receives the call of the other party, and then performs local exchange processing according to the local exchange information of the party and the local exchange information of the other party, so that under the MSC POOL networking, even if The calling party and the called party are respectively located on different MSCs, and the MSC where the calling party or the called party is located can also know the base station controller where the other party is calling, and can make a judgment to start local switching so as to perform local switching processing. The calling MSC sends the local switching information of the other party, so if the call is monitored on one of the MSCs, or the local switching cannot be started when performing operations such as announcements or supplementary services, the other MSC can also know, which is beneficial to local switching realization.

It should be noted that, in the above-mentioned embodiment, one party obtains the other party's information for judgment and then executes the local exchange, but in actual implementation, both the calling party and the called party can obtain the other party's information for judgment, and both process the local exchange, for example as follows plan:

The first mobile switching center obtains the local switching information of the second mobile switching center, and the first mobile switching center performs local switching processing with the local switching information of the second mobile switching center according to its own local switching information;

The second mobile switching center obtains the local switching information of the first mobile switching center, and the second mobile switching center performs local switching processing with the local switching information of the first mobile switching center according to its own local switching information.

Embodiment two,

According to the method described in the first embodiment, this embodiment will take the implementation of local switching by exchanging local switching information between MSCs by using MAP signaling as an example for detailed description. The scheme is as follows:

1. The calling and called MSCs carry and transmit local switching information through MAP signaling.

One MSC uses MAP signaling to send its own local switching information to the other MSC. After the MSC of the other party receives the local switching information of the other party, it saves the received local switching information of the other party's MSC, and returns the local switching information of the other party to the other party by using the MAP signaling. Among them, if the local switching information of one MSC changes during the call process, it is necessary to send the changed local switching information to the other MSC to ensure that both the calling and called MSCs can fully understand the other party's local switching information in a timely manner. information, so that the calling and called MSCs can perform local switching processing according to the complete local switching information, that is, the local switching information in the two MSCs.

2. The calling and called MSCs address each other for MAP signaling through the address of the other party's MSC. Wherein, the method for the calling and called MSCs to obtain the address of the other party's MSC respectively (that is, the calling MSC obtains the MSC address of the called MSC, and the called MSC obtains the address of the calling MSC) can be as follows:

During the call establishment process, the calling and called MSCs pass routing information request (SRI, SENDROUTING INFORMATION Request), roaming number request (PRN, PROVIDEROAMING NUMBER Request), roaming number response (PRN ack, PROVIDEROAMING NUMBER Response), routing information response ( SRI ack, SEND ROUTINGINFORMATION Response) to deliver the calling and called IMSI information and the address of the calling and called MSC.

For example, when a calling party initiates a call, the calling MSC sends a routing information request to the HLR to obtain the called routing information. The routing information request carries the address of the calling MSC and the calling IMSI; the HLR sends a roaming number request to the called MSC to obtain The called roaming number, the roaming number request carries the address of the calling MSC and the information of the calling IMSI, and the called MSC saves the address of the calling MSC and the information of the calling IMSI. When the called MSC returns the roaming number response to the HLR, it carries the address of the called MSC and the called IMSI information. -A saves the address of the called MSC and the information of the called IMSI.

3. The calling and called MSCs use IMSI to associate calls. That is, after the calling and called MSCs receive the local switching information from the other party's MSC, they use the IMSI of the call within the MSC to associate with the corresponding call. Therefore, the calling and called MSCs also need to obtain the IMSI information of the other party separately, which can be realized by carrying the IMSI information of the calling leg of the other party in the MAP signaling sent to the other party. See description in 2.

The above-mentioned MAP signaling that can be used to transmit local exchange information can be implemented by modifying the existing MAP signaling, such as extending the existing MAP signaling SRI and PRN, etc.; it can also be implemented by adding MAP signaling is implemented. In this embodiment, new MAP signaling will be used as an example for description. Assume that the newly added MAP signaling is named [MAP LCLS serevice], and the signaling can carry the following information (choose according to different scenarios):

(1) The IMSI of the other party.

(2) Information about the signaling point of the base station controller where the intra-office call is located.

(3) The local switching indication may be used to bear the local switching capability information. For example, the following indication types can be included:

Local Switch (LCLS, Local Call Local Switch) establishment request; LCLS establishment permission; LCLS establishment rejection; LCLS release request; LCLS release permission; LCLS release rejection; LCLS prohibition indication; LCLS permission indication;

(4) The call identification (Call-ID) corresponding to the intra-office call; the Call-ID is used between the MSC and the base station controller to identify a call leg.

(5) The A port in the local office carries information; when the base station controller cancels the local switching, it needs to use the A ports of the two calling legs to carry information.

The scheme will be described in detail through several specific scenarios below. For convenience of description, it is assumed that the calling terminal is MS-A, the calling MSC is MSC-A, the called terminal is MS-B, and the called MSC is MSC-B.

(1) Scenario 1: Call establishment process

During the call establishment process, the calling and called MSCs, that is, MSC-A and MSC-B, transmit the IMSI of the calling and called users and the address information of the calling and called MSCs through SRI, PRN, PRN ack, and SRI ack. As shown in Figure 2, the specific process can be as follows:

A201, MS-A sends a service request (CM Service Req) to MSC-A;

A202, MSC-A performs authentication and encryption processing on MS-A, for example, Authenticate&Chiper messages are exchanged between MSC-A and MS-A;

A203, MS-A sends a setup (SETUP) message to MSC-A, and MSC-A returns a call proceeding message (Call Proceeding) to MS-A;

A204, MSC-A sends an establishment request (ADD_REQ) to the mobile gateway, and the mobile gateway returns an establishment response (ADD_REPLY) to MSC-A;

A205, MSC-A sends assignment request (ASS_REQ) to base station controller, base station controller sends assignment command (ASS_CMD) to MS-A, MS-A returns assignment complete (ASS_COMP) to base station controller, base station controller Return an Assignment Response (ASS_RSP) to MSC-A;

A206, MSC-A sends a routing information request to the HLR to request routing information of MS-B, wherein the routing information request carries the address of MSC-A and the IMSI of MS-A;

A207, HLR sends a roaming number request to MSC-B to obtain the called roaming number, and the roaming number request carries the address of MSC-A and the IMSI information of MS-A;

A208, MSC-B saves the address of MSC-A and the IMSI information of MS-A, and when MSC-B returns a roaming number response to the HLR, the roaming number response carries the address of MSC-B and the IMSI information of MS-B;

A209, the HLR returns a routing information response to MSC-A, the routing information response carries the address of MSC-B and the IMSI information of MS-B, and MSC-A stores the address of MSC-B and the IMSI information of MS-B;

A210, MSC-A sends an establishment request to the mobile gateway again, and the mobile gateway returns an establishment response to MSC-A;

A211, through the interaction and addressing in step A206 to step A208, MSC-A and MSC-B perform call association according to the IMSI information of the other party saved respectively, and MSC-A sends an initial address message (IAM) to MSC-B, MSC -B sends a paging (Page) to the base station controller, the base station controller sends a page to MS-B, MS-B can return a paging response to the base station controller, and the base station controller receives the paging response (Page rsp) After that, a paging response can be sent to MSC-B;

A212, MSC-B performs authentication and encryption processing on MS-B, for example, Authenticate&Chiper messages are exchanged between MSC-B and MS-B; at the same time, MSC-B sends an establishment request to the mobile gateway, and the mobile gateway can return the establishment Respond to MSC-B; MSC-B sends a setup message to MS-B, and MS-B returns Call Confirmed to MSC-B;

A213, MSC-B sends the establishment request to the mobile gateway again, and the mobile gateway can return the establishment response to MSC-B;

A214, MSC-B sends an assignment request to the base station controller, the base station controller sends an assignment command to MS-B, MS-B returns assignment complete to the base station controller, and the base station controller returns an assignment response to MSC-B;

A215, MS-B can send a ringing message (ALERT) to MSC-B, MSC-B sends an address completion message (ACM) to MSC-A, MSC-A sends an ringing message to MS-A, thereafter, MS-B Send a connection message (CONNECT) to MSC-B, MSC-B can return a connection confirmation (CONNECT_ACK) to MS-B, MSC-B sends an answer message (ANM) to MSC-A, and MSC-A sends a connection message to MS-A , MS-A can return a connection confirmation message to MSC-A; so far, the call establishment between MS-A and MS-B is completed.

A216, MSC-B sends the local switching information request (LCLS infoReq) to MSC-A according to the address of MSC-A, and the MAP signaling used to transmit the local switching information carries the base station controller signaling point where MS-B is located information and the local switching capability information of MSC-B, and may also carry the Call-ID of MS-B;

A217, MSC-A determines whether the local switching start condition is met, and if so, starts the local switching, that is, executes step A218;

For example, according to the signaling point information of the base station controller where MS-A is located and the signaling point information of the base station controller where MS-B is located, it is determined whether the calls of both parties belong to the same base station controller;

If they are the same base station controller, then according to the local switching capability information of MSC-A and the local switching capability information of MSC-B, it is determined that both parties have the ability to start local switching (for example, the calling and called codecs are the same, and the called BSC supports Local switching, when the called user is not monitored, etc.), notify the base station controller where MS-A is located to start local switching (step A218), and notify the mobile gateway to release the A port resources of MS-A (step A219); If it does not have the ability to start local switching, it indicates that local switching is not allowed in the local switching information confirmation message (LCLS info Cnf) returned to MSC-B. After MSC-B receives the local switching information confirmation message, if the local switching Local switching is not initiated if the information acknowledgment message indicates that local switching is not allowed.

If MSC-A does not have the limitation of starting local switching, but MS-A and MS-B do not belong to the same base station controller, it will directly return the local switching information confirmation message to MSC-B, carrying the base station controller information of MS-A. Order point information and corresponding Call-ID.

In this embodiment, it is assumed that both MS-A and MS-B belong to the same base station controller, specifically may belong to the same base station controller, and both MSC-A and MSC-B have the ability to start local switching, so MSC -A starts local switching after receiving the local switching information request sent by MSC-B, that is, executes step A218;

A218, MSC-A sends a local switching command (LOCAL SWITCH COMMAND) to the base station controller to start local switching, the base station controller returns a local switching completion message (LOCALSWITCH COMP) to MSC-A, and MSC-A returns a local switching information confirmation message to MSC-B, the local switching information confirmation message carries MS-A's base station controller signaling point information and the corresponding Call-ID, and indicates that the local switching has been started;

It should be noted that if the base station controller fails to start the local switching, when MSC-A returns the local switching information confirmation message to MSC-B, the signaling point information of the base station controller where MS-A is located is carried in the local switching information confirmation message , and indicates that local switching is not started.

A219, MSC-A sends a deletion request (SUB_REQ) to the mobile gateway to release the A port resources of MS-A; the mobile gateway can return a deletion response (SUB_REPLY) to MSC-A;

A220, MSC-B receives after MSC-A returns the local exchange information confirmation message, if the local exchange information confirmation message indicates that the local exchange has started, then send a delete request to the mobile gateway to release the A port resource of MS-B; The gateway can return a deletion response to MSC-B; if the local switching information confirmation message indicates that the local switching is not started, no action will be taken.

So far, the establishment of the local exchange is completed. It should be noted that there is no need to maintain a MAP connection between the calling and called MSCs, that is, between MSC-A and MSC-B; in addition, after the local switching is started, the relay resources between MSC-A and MSC-B will not be released , because if it is released, the established local exchange cannot be released later.

Of course, MSC-A can also initiate the local exchange information request first, and the implementation method is similar to that firstly initiated by MSC-B described above, that is, after MSC-B receives the local exchange information request sent by MSC-A, MSC- B determines whether the calls of both parties belong to the same base station controller according to the signaling point information of the base station controller where MS-A is located and the signaling point information of the base station controller where MS-B is located; When the local switching capability information of the party and the local switching capability information of the other party determine that both parties have the ability to start local switching (for example, the codec of the calling party and the called party are the same, the called BSC supports local switching, and the called user is not monitored, etc.), notify the MS - The base station controller where B is located starts local switching, and notifies the mobile gateway to release the A port resources of MS-B. In addition, MSC-B can also return a local switching information confirmation message to MSC-A, and the local switching information confirmation message carries MS-B's base station controller signaling point information and corresponding Call-ID, and indicates that local switching has been started; if it is determined that the local office does not have the ability to start local switching, then in the local switching information confirmation message returned to MSC-A Indicates that local switching is not allowed. After MSC-A receives the local switching information acknowledgment message, if the local switching information acknowledgment message indicates that local switching is not allowed, local switching will not be started. If MSC-B does not have the limitation of starting local switching, but MS-A and MS-B do not belong to the same base station controller, it will directly return the local switching information confirmation message to MSC-A, carrying the base station controller information of MS-B. Order point information and corresponding Call-ID.

In addition, it should be noted that, in addition to letting one MSC judge and start the local switching as described above, the calling and called MSCs can also judge and start the local switching respectively. For example, after step A216, MSC-A can return a local exchange information confirmation message to MSC-B. Then, MSC-A and MSC-B judge whether their own local exchange start conditions are met, and if yes, MSC-A and MSC -B respectively start local switching, that is, on the one hand, MSC-A notifies the base station controller where MS-A is located to start local switching, and notifies the mobile gateway to release the A port resources of MS-A; on the other hand, MSC-B also notifies MS- The base station controller where B is located starts the local switching, and notifies the mobile gateway to release the resources of the port A of MS-B.

During the call, MSC-A and MSC-B can update the local switching capability information of the call through the local switching information request and local switching information confirmation messages, that is, when the local switching capability information of the call changes, MSC-A It needs to interact dynamically with MSC-B. For example, when a call is initiated, local switching is not started because MS-A and MS-B are not in the same base station controller, but there are no other local switching restrictions. During the call, if the user of MS-A is monitored or If the supplementary service is used, MSC-A needs to notify MSC-B that the call no longer has the local switching capability; if the follow-up monitoring is released or the supplementary service ends, MSC-A needs to notify MSC-B that the call has the local switching capability again. When a call does not have the local switching capability, even if the calling and called users belong to the same base station controller, the local switching will not be started.

(2) Scenario 2: After the local exchange is established, the MSC requests to release the local exchange

When MSC-A needs to cancel the local exchange for operations such as supplementary services, MSC-A applies to the mobile gateway for A port resources according to the local exchange information of the two parties. If the application for A port resources is successful, it sends a local exchange information request to MSC-B. Notify MSC-B and request to cancel the local switching; MSC-B applies to the mobile gateway for port A resources after receiving the local switching information request, and returns the local switching information confirmation message to MSC-A if the resource of port A can be applied for. And carry the corresponding A port resources in the local switching information confirmation message. After MSC-A receives the local switching information confirmation message from MSC-B, it instructs the base station controller to cancel the local switching. After the local switching is cancelled, MSC-A passes through The local switching information request informs MSC-B that the local switching has been released. It should be noted that if MSC-A fails to request the base station controller to release the local switching, MSC-A should also notify MSC-B through a local switching information request, so that MSC-A and MSC-B release the A port resources that have been applied for.

Of course, in addition to the MSC of one party described above, for example, MSC-A requires the base station controller to release the local exchange, the MSCs of both parties, that is, MSC-A and MSC-B, can also request the base station controller to release the local exchange. exchange. For example, it could be as follows:

When MSC-A needs to cancel the local exchange for operations such as supplementary services, MSC-A applies to the mobile gateway for A port resources according to the local exchange information of the two parties. If the application for A port resources is successful, it sends a local exchange information request to MSC-B. Notify MSC-B and request to cancel the local switching; MSC-B applies to the mobile gateway for A port resources after receiving the local switching information request, and returns a local switching information confirmation message to MSC-A, and the local switching information confirmation message contains It does not need to carry the A port resource information, and at the same time instructs the base station controller to cancel the local switching, and returns a local switching confirmation message to inform MSC-A that the local switching has been cancelled. After receiving the local switching confirmation message, MSC-A instructs the base station controller to cancel the local switching .

Of course, MSC-A can also directly request MSC-B to release the local switching. After receiving the request, MSC-B applies to the mobile gateway for port A resources. If MSC-B successfully applies for port A resources, it returns a local switching confirmation message. Inform MSC-A that after MSC-A receives the local exchange confirmation message, MSC-A applies to the mobile gateway for port A resources. If MSC-A fails to apply for port A resources, the local exchange will not be canceled; if MSC-A applies If it succeeds, it will instruct the base station controller to cancel the local switching; if MSC-B fails to apply for A port resources, it will return a rejection message to MSC-A, and MSC-A will not cancel the local switching after receiving the rejection message. Among them, MSC-A will do different processing for different reasons for starting and releasing local switching. For example, if it is to perform supplementary services, MSC-A will refuse the supplementary services; if it is to perform legal interception, it can release the call Or not to monitor.

(3) Scenario 3: Local switching is established during the switching process

No local switching is established during the call, but after the handover, the base station controllers of the calling party and the called party belong to the same base station controller, and both parties have the ability to start the local switching, then the local switching needs to be established at this time. That is to say, when a user is handed over to the base station controller where another user is located, and the local switching establishment conditions are met, the local switching needs to be established.

In the following, an example will be given to illustrate the establishment method of the local exchange if a handover between base station controllers occurs on one party in the inter-office call flow. The handover between base station controllers includes two types, one is handover between base station controllers within an office, and the other is handover between base station controllers in an office. Assume that the base station controller before the handover is the source base station controller, the base station controller after the handover is the target base station controller, the source base station controller is BSC1, and the target base station controller is BSC2;

First, describe the scenario where the caller is handed over between the base station controllers in the office in the inter-office call process, as shown in Figure 3, and the specific process is as follows:

B201, BSC1 sends a handover request message (Handover Required) to MSC-A, MSC-A sends a setup request to the mobile gateway, and the mobile gateway can return a setup response to MSC-A;

B202, MSC-A sends a handover request (Handover Request) to BSC2, which carries a local switching indication (LS ind) in the handover request, such as instructing BSC2 to start local switching or release local switching, etc.;

For example, MSC-A can judge whether MSC-B has the ability to initiate local switching according to the relevant information exchanged between MSC-A and MSC-B during the call establishment phase and call process, such as the local switching capability information of MSC-B. If it is available, when MSC-A sends a handover request to BSC2, it can instruct BSC2 to start local switching in the handover request, and carry the Call-ID of the call after switching; In , there is no indication to start local switching;

BSC2 can return a handover request acknowledgment message (Handover Request ack) to MSC-A, and the handover request acknowledgment message carries local switching acknowledgment information (LS ack);

B203, MSC-A sends a handover command (Handover Command) to BSC1;

B204, BSC2 sends a discovery handover message (Handover Detect) to MSC-A, and sends handover completion (Handover Complete) to MSC-A;

B205, MSC-A sends a clear command (Clear Command) to BSC1, and BSC1 returns a clear complete message (Clear Complete) to MSC-A;

B206. MSC-A sends a local switching information request to MSC-B to start local switching. The local switching information request carries the signaling point information of the base station controller where the calling party is located, the corresponding Call-ID, and the local switching has been started. Instruction; MSC-B can return a local switching information confirmation message to MSC-A. After that, if the conditions for starting local switching are met, MSC-A will notify the base station controller where MS-A is located to start local switching, and notify the mobile gateway to release the MS -A port resources of A; at this time, MSC-B also notifies the base station controller where MS-B is located to start local switching, and notifies the mobile gateway to release the port A resources of MS-B. For details about how to release local switching, refer to the relevant description in Scenario 1, which will not be repeated here.

The following describes a scenario in which a user has an inter-office base station controller handover in an inter-office call flow, that is, the source base station controller and the target base station controller belong to different MSCs. Here, it is assumed that the calling user undergoes inter-office base station controller switching, the source MSC is MSC-A, the source BSC is BSC1, the target MSC is MSC-A', the target BSC is BSC2, the called MSC is MSC-B, and the called MSC is MSC-B. The called BSC is BSC2, as shown in Figure 4, and the specific process is as follows:

C201. After MSC-A receives the handover request, if MSC-A judges that local switching can be started, for example, MSC-A determines that both parties have the ability to start local switching according to the local switching capability information of its own party and the local switching capability information of the other party. Then, the handover request sent to MSC-A' carries an indication of starting local switching, so that after the handover is completed, MSC-A' notifies the mobile gateway to release its own A port resources and informs the base station according to the indication of starting local switching The controller starts the local switching, and MSC-A' returns a handover response indicating that the local switching is successfully started to MSC-A; wherein, the handover request sent to MSC-A' may be a MAP Prepare Handover Req;

C202, MSC-A' sends a handover request to BSC2, the handover request carries a local switching instruction, such as instructing BSC2 to start local switching or cancel local switching, etc., and Call-ID BSC2 carrying the switched call can return a switching request confirmation message For MSC-A', the handover request confirmation message carries local switching confirmation information;

C203, MSC-A' sends a handover request confirmation message to MSC-A, and the handover request confirmation message carries local switching confirmation information; wherein, the handover request confirmation message can also be a MAP Prepare Handover Resp;

C204. After the handover is completed, MSCA' notifies the mobile gateway to release the corresponding A port bearer, and MSC-A and/or MSC-B notifies the base station controller to start local switching. The process between MSC-A and MSC-B is the same as that of the user The process when the base station controller handover occurs in the office, for example, MSC-A sends a local switching information request to MSC-B, MSC-B returns a local switching information confirmation message to MSC-A, and MSC-B notifies the mobile gateway to release A Port resources, etc., for details, refer to the previous embodiments, and will not be repeated here.

Of course, in addition to the MSC-A described above judging whether local switching can be started, it can also be judged by MSC-A', as follows:

After the inter-office handover is completed, regardless of whether the local switching is started, MSC-A must send local switching information to MSC-A', such as notifying MSC-A' of the local switching capability of the call and the control of the base station where MSC-B is located. Signaling point information and Call-ID of the device, so that the target mobile switching center performs local switching processing according to the local switching information of its own party and the local switching information of the other party. In addition, in the subsequent call process, if the local switching capability information of the call or the signaling point information of the base station controller where the MSC-B is located changes, the MSCA must also notify the MSCA'.

The following describes the check and start-up process of the local exchange when the intra-office handover occurs after the inter-office handover is completed. That is, if after the inter-office handover, the caller and the called party are not on the same base station controller and do not start local switching, the subsequent intra-office inter-base station controller handover occurs in MSC-A'. , then local switching can be started at this time.

After MSC-A' receives the handover request, it first sends a local switching information request to inquire whether MSC-A can start local switching. The local switching information request carries the handover target BSC information. MSC-A' returns an indication that local switching is allowed to start, and MSC-A' continues to perform subsequent handover and start local switching operations. For details, refer to the previous embodiment. After the handover is completed, MSC-A' will notify MSC-A that it has started local exchange. MSC-A needs to deliver the local switching information of MSC-A' to MSC-B.

Of course, MSC-A' can also judge whether local switching can be started by itself, that is, MSC-A' can judge whether local switching can be started after receiving the handover request, and if it can be started, start local switching during the handover process, and the handover is completed Afterwards, MSC-A' notifies MSC-A that the local switching has been started, and MSC-A needs to transmit the local switching information of MSC-A' to MSC-B.

It should be noted that, in the MSC POOL network, after the calling party is switched across base station controllers, even if local switching is not activated, the MSC where the call is located must notify the other MSC of the new base station controller information.

(4) Scenario 4: Release local switching during switching

Firstly, in the inter-office call flow, when the user has an intra-office base station controller handover, the flow of local switching release is described. as follows:

MSC-A receives the handover request, and when it judges that local switching needs to be released according to the received handover request, it sends a local switching release request to MSC-B, such as sending a local switching information request to MSC-B. After receiving the handover request, MSC-B can The local switching release request judges whether the local switching can be released. If it cannot be released, it returns a rejection message to MSC-A. After receiving the rejection message, MSC-A refuses the handover; if it can be released, it applies to the mobile gateway. A port resources, and return to MSC-A a confirmation message indicating successful application for A port resources, such as returning a local switching information confirmation message to MSC-A, wherein the local switching information confirmation message carries MSC-B to apply to the mobile gateway After receiving the confirmation message, MSC-A applies for A port resources from the mobile gateway, notifies the base station controller to release the local switching, and performs subsequent handover processing. The handover command sent to the source BSC carries the release of the local After the switching instruction and the A port resource information applied by MSC-B are completed, MSC-B is notified that the local switching has been released.

Of course, MSC-A can also send a local switching information request to MSC-B after applying for port A resources from MGW, that is, MSC-A applies for port A resources to the mobile gateway, and only sends local switching information if the application for port A resources is successful. Information request to MSC-B.

In addition, in addition to the above description that only one MSC, such as MSC-A, instructs the base station controller to release the local switching, MSCs of both parties, such as MSC-A and MSC-B, can also instruct the BSC to release the local switching. as follows:

MSC-A receives the handover request, and when it judges that local switching needs to be released according to the received handover request, it sends a local switching release request to MSC-B, such as sending a local switching information request to MSC-B. The local switching information request judges whether it is allowed to cancel the local switching. If it cannot be canceled, it will return a rejection message to MSC-A. After receiving the rejection message, MSC-A will refuse the handover; if it can be canceled, it will apply to the mobile gateway A port resources, and return the local switching to release permission instruction to MSC-A (without carrying the applied A port resource information), MSC-A performs subsequent handover processing according to the local switching release permission instruction, including applying for A port resources to the mobile gateway, And notify the base station controller to cancel the local switching. After the handover is completed, MSC-A sends a notification to MSC-B about the cancellation of the local switching, and MSC-B cancels the local switching according to the notification about the cancellation of the local switching, and returns an acknowledgment message.

Of course, MSC-A can also send a local switching information request to MSC-B after applying for port A resources from MGW, that is, MSC-A applies for port A resources to the mobile gateway, and only sends local switching information if the application for port A resources is successful. Information request to MSC-B.

If the user has inter-office base station controller handover and needs to release the local exchange, the interaction between MSC-A and MSC-B is the same as the intra-office handover, which will not be described here. It should be noted that at this time, MSC-A Before switching, the permission of MSC-A and MSC-B must be obtained.

As can be seen from the above, the present embodiment uses MAP signaling to carry out the interaction of local exchange information between MSCs, so that the MSC can perform local exchange processing according to complete local exchange information (the local exchange information of the local party and the other party), so that In the MSC POOL network, even if the calling party and the called party are located on different MSCs, the MSCs where the calling party and the called party are located can also know the base station controller where the other party is calling, and can make a judgment to start the local exchange for local exchange processing. , and, since the local switching information between MSCs can be transmitted through MAP signaling, if a call is monitored on one of the MSCs, or the local switching cannot be started when performing operations such as announcements or supplementary services, the other MSC will also It can be known that it is beneficial to the realization of local switching. Furthermore, the use of MAP signaling to transmit local exchange information between MSCs does not require too many changes to the MSCs, which is beneficial to implementation.

Embodiment three,

According to the method described in Embodiment 1, this embodiment will take the example of exchanging local switching information between MSCs by using relay signaling to realize local switching in detail. The scheme is as follows:

1. The calling and called MSCs exchange information locally through relay signaling.

One MSC uses relay signaling to send its local switching information to the other MSC, including the signaling point information of the base station controller where the calling leg of the local party is located and/or local switching capability information. After the MSC of the other party receives the local switching information of the other party, it saves the received local switching information of the other party's MSC, and returns the local switching information of the other party to the other party by using relay signaling. Among them, if the local switching information of one MSC changes during the call process, it is necessary to send the changed local switching information to the other MSC to ensure that both the calling and called MSCs can fully understand the other party's local switching information in a timely manner. information, so that the calling and called MSCs can perform local switching processing according to the complete local switching information, that is, the local switching information in the two MSCs.

2. The above-mentioned relay signaling that can be used to transmit locally switched information can use the relay signaling type as: Bearer Independent Call Control Protocol (BICC, Bearer Independent Call Control Protocol), or Session Initiation Protocol (SIP , Session Initiation Protocol), or integrated services digital network user part (ISUP, Integrated Services Digital Network User Part) and other relay signaling, and can also be realized by extending the existing relay signaling, such as:

The information request (INR, Information Request) and information (INF, Information) of the existing BICC message can be extended, and the INR and INF of the existing ISUP message can also be extended;

Wherein, SIP signaling can use SIP-I signaling, in addition, can use INFO (information, Information) to carry the INR of the ISUP message of extension, use 200 OK (a kind of response message) to carry the INF of the ISUP message of extension, In this way, local switching information can be transferred between the calling and called MSCs.

The extended INR and INF can carry the following information:

(1) Information about the signaling point of the base station controller where the calling party is located in the local office.

(2) The local switching indication, which can be used to carry the local switching capability information of the caller in the local office of the first mobile switching center or the second mobile switching center. For example, the following indication types can be included:

LCLS Establishment Request; LCLS Establishment Allow; LCLS Establishment Reject; LCLS Release Request; LCLS Release Allow; LCLS Release Reject; LCLS Prohibition Indication;

(3) The Call-ID corresponding to the intra-office call. The Call-ID is used between the MSC and the base station controller to identify a call leg.

(4) Port A in the office bears information. When the base station controller releases the local switching, it needs to use the A ports of the two call legs to carry information. In addition, in addition to the above-mentioned exchange of information between the calling and called MSCs by extending the relay signaling, it is also possible to implement the exchange of information between the calling and called MSCs by adding a new relay signaling. Interaction for local exchange of information. For example, add LCLS Request and LCLS information of BICC messages (it should be noted that the signaling names here are only examples, and it should be understood that they can also be other signaling names); or add ISUP messages LCLSRequest, LCLS information, etc. Among them, SIP signaling can use SIP-I signaling. In addition, INFO can be used to carry the LCLS Request of the newly added ISUP message, and 200 OK can be used to carry the LCLS information of the newly added ISUP message. MSCs to transfer local exchange information.

For the convenience of description, in the embodiment of the present invention, the extended SIP signaling will be taken as an example for description.

The scheme will be described in detail through several specific scenarios below. For convenience of description, it is assumed that the calling terminal is MS-A, the calling MSC is MSC-A, the called terminal is MS-B, and the called MSC is MSC-B.

(1) Scenario 1: Call establishment process

During the call establishment process, the calling and called MSCs, that is, MSC-A and MSC-B, transmit the local interaction information of both parties through extended SIP signaling, among which, INFO can be used to carry the INR of the extended ISUP message, and 200 OK can be used to INF carrying extended ISUP messages. As shown in Figure 5, the specific process can be as follows:

A301, MS-A sends a service request (CM Service Req) to MSC-A;

A302, MSC-A performs authentication and encryption processing on MS-A, for example, the interaction of Authenticate&Chiper messages between MSC-A and MS-A;

A303, MS-A sends a setup (SETUP) message to MSC-A, and MSC-A returns a call proceeding message (Call Proceeding) to MS-A;

A304, MSC-A sends an establishment request (ADD_REQ) to the mobile gateway, and the mobile gateway returns an establishment response (ADD_REPLY) to MSC-A;

A305. MSC-A sends an assignment request (ASS_REQ) to the base station controller, and the base station controller sends an assignment command (ASS_CMD) to MS-A, and MS-A returns assignment completion (ASS_COMP) to the base station controller, and the base station controller Return an Assignment Response (ASS_RSP) to MSC-A;

A306, MSC-A sends a routing information request to the HLR, requesting the routing information of MS-B;

A307, HLR sends a roaming number request to MSC-B to obtain the called roaming number;

A308, MSC-B returns a roaming number response to the HLR;

A309, HLR returns routing information response to MSC-A;

A310, MSC-A sends an establishment request to the mobile gateway again, and the mobile gateway returns an establishment response to MSC-A;

A311, MSC-A sends an initial address message (IAM) to MSC-B, MSC-B sends a page (Page) to the base station controller, the base station controller sends a page to MS-B, and MS-B can return a page response To the base station controller, after the base station controller receives the paging response (Page rsp), it can send the paging response to MSC-B;

A312, MSC-B performs authentication and encryption processing on MS-B, for example, Authenticate&Chiper messages are exchanged between MSC-B and MS-B; at the same time, MSC-B sends an establishment request to the mobile gateway, and the mobile gateway can return the establishment Respond to MSC-B; MSC-B sends a setup message to MS-B, and MS-B returns Call Confirmed to MSC-B;

A313, MSC-B sends the establishment request to the mobile gateway again, and the mobile gateway can return the establishment response to MSC-B;

A3 14. MSC-B sends an assignment request to the base station controller, the base station controller sends an assignment command to MS-B, MS-B returns assignment complete to the base station controller, and the base station controller returns an assignment response to MSC-B ;

A315, MS-B can send an alarm message (ALERT) to MSC-B, MSC-B sends an address complete message (ACM) to MSC-A, MSC-A sends an alarm message to MS-A, after that, MS-B Send a connection message (CONNECT) to MSC-B, MSC-B can return a connection confirmation (CONNECT_ACK) to MS-B, MSC-B sends an answer message (ANM) to MSC-A, and MSC-A sends a connection message to MS-A , MS-A can return a connection confirmation message to MSC-A; so far, the call establishment between MS-A and MS-B is completed.

A3 16. MSC-B sends an INFO[INR] message to MSC-A. The INFO[INR] message carries the signaling point information of the base station controller where MS-B is located and the local switching capability information of MSC-B. It can also carry Call-ID of MS-B;

A317, MSC-A judges whether the local switching activation condition is met, and if yes, then starts the local switching, that is, executes step A318;

For example, according to the signaling point information of the base station controller where MS-A is located and the signaling point information of the base station controller where MS-B is located, it is determined whether the calls of both parties belong to the same base station controller;

If they are the same base station controller, then according to the local switching capability information of MSC-A and the local switching capability information of MSC-B, it is determined that both parties have the ability to start local switching (for example, the calling and called codecs are the same, and the called BSC supports Local switching, when the called user is not monitored, etc.), notify the base station controller where MS-A is located to start local switching (step A318), and notify the mobile gateway to release the A port resources of MS-A (step A319); If it does not have the ability to start local switching, it indicates that local switching is not allowed in the 200 OK[INF] message returned to MSC-B. After MSC-B receives the 200 OK[INF] message, if the 200 OK[INF] message Indicates that local swapping is not allowed, local swapping will not be started.

If MSC-A does not have the limitation of starting local switching, but MS-A and MS-B do not belong to the same base station controller, it will directly return a 200 OK[INF] message to MSC-B, carrying the base station controller of MS-A Signaling point information and corresponding Call-ID.

In this embodiment, it is assumed that both MS-A and MS-B belong to the same base station controller, specifically may belong to the same base station controller, and both MSC-A and MSC-B have the ability to start local switching, so MSC -A starts local switching after receiving the 200 OK[INF] message sent by MSC-B, that is, executes step A318;

A318, MSC-A sends a local switching command (LOCAL SWITCH COMMAND) to the base station controller to start local switching, the base station controller returns a local switching completion message (LOCALSWITCH COMP) to MSC-A, and MSC-A returns a 200 OK[INF] message For MSC-B, the 200OK[INF] message carries MS-A's base station controller signaling point information and the corresponding Call-ID, and indicates that local switching has been started;

It should be noted that if the base station controller fails to start local switching, when MSC-A returns a 200 OK[INF] message to MSC-B, the 200 OK[INF] message carries the signaling of the base station controller where MS-A is located. Points to info and indicates that local switching is not enabled.

A319, MSC-A sends a deletion request (SUB_REQ) to the mobile gateway to release the A port resource of MS-A; the mobile gateway can return a deletion response (SUB_REPLY) to MSC-A;

A320, MSC-B receives the 200 OK[INF] message returned by MSC-A, if the 200 OK[INF] message indicates that the local switching has been started, it sends a delete request to the mobile gateway to release the A port resources of MS-B ; The mobile gateway may return a delete response to MSC-B; if the 200 OK[INF] message indicates that local switching has not been started, then no action will be taken.

So far, the establishment of the local exchange is completed. It should be noted that there is no need to maintain a MAP connection between the calling and called MSCs, that is, between MSC-A and MSC-B; in addition, after the local switching is started, the relay resources between MSC-A and MSC-B will not be released , because if it is released, the established local exchange cannot be released later.

Of course, the INFO[INR] message can also be first initiated by MSC-A, and the implementation method is similar to that firstly initiated by MSC-B described above, that is, after MSC-B receives the INFO[INR] message sent by MSC-A, MSC-B determines whether the calls of both parties belong to the same base station controller according to the signaling point information of the base station controller where MS-A is located and the signaling point information of the base station controller where MS-B is located; According to the local switching capability information of the local party and the local switching capability information of the other party, it is determined that both parties have the capability to initiate local switching (for example, the codec of the calling party and the called party is the same, the called BSC supports local switching, and the called party is not monitored, etc.), Notify the base station controller where MS-B is located to start local switching, and notify the mobile gateway to release the A port resource of MS-B. In addition, MSC-B can also return a 200 OK[INF] message to MSC-A. The 200 OK[INF] The message carries the MS-B base station controller signaling point information and the corresponding Call-ID, and indicates that the local exchange has been started; if it is determined that the local office does not have the ability to start the local exchange, it returns to MSC-A with 200 OK[ INF] message indicates that local exchange is not allowed. After MSC-A receives the 200 OK[INF] message, if the 200 OK[INF] message indicates that local exchange is not allowed, then local exchange will not be started. If MSC-B does not have the limitation of starting local switching, but MS-A and MS-B do not belong to the same base station controller, it will directly return a 200 OK[INF] message to MSC-A, carrying the base station controller of MS-B Signaling point information and corresponding Call-ID.

In addition, it should be noted that, in addition to letting one MSC judge and start the local switching as described above, the calling and called MSCs can also judge and start the local switching respectively. For example, after step A316, MSC-A can return a 200 OK[INF] message to MSC-B, then, MSC-A and MSC-B judge whether the local switching start conditions of themselves are possessed respectively, and if possessed, MSC-A Start local switching with MSC-B respectively, that is, on the one hand, MSC-A notifies the base station controller where MS-A is located to start local switching, and notifies the mobile gateway to release the A port resources of MS-A; on the other hand, MSC-B also notifies The base station controller where MS-B is located starts the local switching, and notifies the mobile gateway to release the A port resource of MS-B.

During the call, MSC-A and MSC-B can update the local switching capability information of the call through the INFO[INR] message and 200OK[INF] message, that is, when the local switching capability information of the call changes, MSC- A and MSC-B should interact dynamically. For example, when a call is initiated, local switching is not started because MS-A and MS-B are not in the same base station controller, but there are no other local switching restrictions. During the call, if the user of MS-A is monitored or If the supplementary service is used, MSC-A needs to notify MSC-B that the call no longer has the local switching capability; if the follow-up monitoring is released or the supplementary service ends, MSC-A needs to notify MSC-B that the call has the local switching capability again. When a call does not have the local switching capability, even if the calling and called users belong to the same base station controller, the local switching will not be started.

(2) Scenario 2: After the local exchange is established, the MSC requests to release the local exchange

When MSC-A needs to cancel the local exchange for operations such as supplementary services, if MSC-A applies for A port resources from the mobile gateway according to the local exchange information of the two parties, if the application for A port resources is successful, it will send INFO[INR] to MSC-B message, notify MSC-B and request to cancel the local exchange; MSC-B receives the INFO[INR] message, applies to the mobile gateway for port A resources, and returns 200 OK[ to MSC-A if it can apply for port A resources INF] message, and carry the corresponding A port resources in the 200 OK[INF] message, after MSC-A receives the 200 OK[INF] message from MSC-B, it instructs the base station controller to release the local switching, after the local switching is released , MSC-A informs MSC-B that the local exchange has been released through the INFO[INR] message. It should be noted that if MSC-A requests the base station controller to release the local switching failure, MSC-A should also notify MSC-B through the INFO[INR] message, so that MSC-A and MSC-B can release the A port resources that have been applied for. .

Of course, in addition to the MSC of one party described above, for example, MSC-A requires the base station controller to release the local exchange, the MSCs of both parties, that is, MSC-A and MSC-B, can also request the base station controller to release the local exchange. exchange. For example, it could be as follows:

When MSC-A needs to cancel the local exchange for operations such as supplementary services, if MSC-A applies for A port resources from the mobile gateway according to the local exchange information of the two parties, if the application for A port resources is successful, it will send INFO[INR] to MSC-B message, notify MSC-B and request to release the local switching; after receiving the INFO[INR] message, MSC-B applies to the mobile gateway for A port resources, and returns a 200 OK[INF] message to MSC-A, the 200 OK The [INF] message does not need to carry the A port resource information, and at the same time instructs the base station controller to release the local switching, and returns a 200 OK[INF] message to inform MSC-A that the local switching has been released, and MSC-A receives the 200 OK[INF] message After that, instruct the base station controller to release the local switching.

Of course, MSC-A can also directly request MSC-B to release the local switching. After receiving the request, MSC-B applies to the mobile gateway for port A resources. If MSC-B successfully applies for port A resources, it returns a local switching confirmation message. Inform MSC-A that after MSC-A receives the local exchange confirmation message, MSC-A applies to the mobile gateway for port A resources. If MSC-A fails to apply for port A resources, the local exchange will not be canceled; if MSC-A applies If it succeeds, it will instruct the base station controller to cancel the local switching; if MSC-B fails to apply for A port resources, it will return a rejection to MSC-A. After MSC-A receives the rejection message, it will not release the local switching. Among them, MSC-A will do different processing for different reasons for starting and releasing local switching. For example, if it is to perform supplementary services, MSC-A will refuse the supplementary services; if it is to perform legal interception, it can release the call Or not to monitor.

(3) Scenario 3: Local switching is established during the switching process

No local switching is established during the call, but after the handover, the base station controllers of the calling party and the called party belong to the same base station controller, and both parties have the ability to start the local switching, then the local switching needs to be established at this time. That is to say, when a user is handed over to the base station controller where another user is located, and the local switching establishment conditions are met, the local switching needs to be established.

In the following, an example will be given to illustrate the establishment method of the local exchange if a handover between base station controllers occurs on one party in the inter-office call flow. The handover between base station controllers includes two types, one is handover between base station controllers within an office, and the other is handover between base station controllers in an office. Assume that the base station controller before the handover is the source base station controller, the base station controller after the handover is the target base station controller, the source base station controller is BSC1, and the target base station controller is BSC2;

First, describe the scenario where the caller is handed over between the base station controllers in the office during the inter-office call process, as shown in Figure 6, and the specific process is as follows:

B301, BSC1 sends a handover request message (Handover Required) to MSC-A, MSC-A sends a setup request to the mobile gateway, and the mobile gateway can return a setup response to MSC-A;

B302, MSC-A sends a handover request (Handover Request) to BSC2, which carries a local switching indication (LS ind), such as instructing BSC2 to start local switching or release local switching, etc.;

For example, MSC-A can judge whether MSC-B has the ability to initiate local switching according to the relevant information exchanged between MSC-A and MSC-B during the call establishment phase and call process, such as the local switching capability information of MSC-B. If it is available, when MSC-A sends a handover request to BSC2, it can instruct BSC2 to start local switching in the handover request, and carry the Call-ID of the call after switching; In , there is no indication to start local switching;

BSC2 can return a handover request acknowledgment message (Handover Request ack) to MSC-A, and the handover request acknowledgment message carries local switching acknowledgment information (LS ack);

B303, MSC-A sends a handover command (Handover Command) to BSC1;

B304, BSC2 sends a discovery handover message (Handover Detect) to MSC-A, and sends a handover completion (Handover Complete) to MSC-A;

B305, MSC-A sends a clear command (Clear Command) to BSC1, and BSC1 returns a clear complete message (Clear Complete) to MSC-A;

B306. MSC-A sends an INFO[INR] message to MSC-B to start local switching. The INFO[INR] message carries the signaling point information of the base station controller where the calling party is located, the corresponding Call-ID, and the local switching status. Start instruction; MSC-B can return a 200 OK[INF] message to MSC-A. After that, if the conditions for starting local switching are met, MSC-A will notify the base station controller where MS-A is located to start local switching, and notify the mobile The gateway releases the port A resources of MS-A; at this time, MSC-B also notifies the base station controller where MS-B is located to start local switching, and notifies the mobile gateway to release port A resources of MS-B. For details on how to establish a local exchange, refer to the relevant description in Scenario 1, which will not be repeated here.

The following describes a scenario in which a user has an inter-office base station controller handover in an inter-office call flow, that is, the source base station controller and the target base station controller belong to different MSCs. Here, it is assumed that the calling user undergoes inter-office base station controller switching, the source MSC is MSC-A, the source BSC is BSC1, the target MSC is MSC-A', the target BSC is BSC2, the called MSC is MSC-B, and the called MSC is MSC-B. The called BSC is BSC2, as shown in Figure 7, and the specific process is as follows:

C301. After MSC-A receives the handover request, if MSC-A judges that local switching can be started, for example, MSC-A determines that both parties have the ability to start local switching according to the local switching capability information of its own party and the local switching capability information of the other party. Then, the handover request sent to MSC-A' carries an indication of starting local switching, so that after the handover is completed, MSC-A' notifies the mobile gateway to release its own A port resources and informs the base station according to the indication of starting local switching The controller starts the local switching, and MSC-A' returns a handover response indicating that the local switching is successfully started to MSC-A; wherein, the handover request sent to MSC-A' may be a MAP Prepare Handover Req;

C302, MSC-A' sends a handover request to BSC2, the handover request carries a local switching instruction, such as instructing BSC2 to start local switching or cancel local switching, etc., and Call-ID BSC2 carrying the switched call can return a switching request confirmation message For MSC-A', the handover request confirmation message carries local switching confirmation information;

C303, MSC-A' sends a handover request confirmation message to MSC-A, and the handover request confirmation message carries local switching confirmation information; wherein, the handover request confirmation message can also be a MAP Prepare Handover Resp;

C304. After the handover is completed, MSCA' notifies the mobile gateway to release the corresponding A port bearer, and MSC-A and/or MSC-B notifies the base station controller to start local switching, and the process between MSC-A and MSC-B is the same as that of the user The process when the base station controller handover occurs in the office, for example, MSC-A sends an INFO[INR] message to MSC-B, MSC-B returns a 200 OK[INF] message to MSC-A, and MSC-B notifies the mobile gateway For the release of port A resources, etc., refer to the previous embodiments for specific details, and details will not be repeated here.

Of course, in addition to the MSC-A described above judging whether local switching can be started, it can also be judged by MSC-A', as follows:

After the inter-office handover is completed, regardless of whether the local switching is started, MSC-A must send local switching information to MSC-A', such as notifying MSC-A' of the local switching capability of the call and the control of the base station where MSC-B is located. Signaling point information and Call-ID of the device, so that the target mobile switching center performs local switching processing according to the local switching information of its own party and the local switching information of the other party. In addition, in the subsequent call process, if the local switching capability information of the call or the signaling point information of the base station controller where the MSC-B is located changes, the MSCA must also notify the MSCA'.

The following describes the check and start-up process of the local exchange when the intra-office handover occurs after the inter-office handover is completed. That is, if after the inter-office handover, the caller and the called party are not on the same base station controller and do not start local switching, the subsequent intra-office inter-base station controller handover occurs in MSC-A'. , then local switching can be started at this time.

After receiving the handover request, MSC-A' first sends an INFO[INR] message to inquire whether MSC-A can start local switching. The INFO[INR] message carries the handover target BSC information. If MSC-A judges that local switching can be started, Then give MSC-A' an instruction to allow the start of local switching, and MSC-A' continues to perform subsequent handover and start local switching operations. For details, refer to the previous embodiment. After the handover is completed, MSC-A' will notify MSC-A Local switching has been started. MSC-A needs to deliver the local switching information of MSC-A' to MSC-B.

Of course, MSC-A' can also judge whether local switching can be started by itself, that is, MSC-A' can judge whether local switching can be started after receiving the handover request, and if it can be started, start local switching during the handover process, and the handover is completed Afterwards, MSC-A' notifies MSC-A that the local switching has been started, and MSC-A needs to transmit the local switching information of MSC-A' to MSC-B.

It should be noted that, in the MSC POOL network, after the calling party is switched across base station controllers, even if local switching is not activated, the MSC where the call is located must notify the other MSC of the new base station controller information.

(4) Scenario 4: Release local switching during switching

Firstly, in the inter-office call flow, when the user has an intra-office base station controller handover, the flow of local switching release is described. as follows:

MSC-A receives the handover request, and when it judges that the local switching needs to be released according to the received handover request, it sends a local switching release request to MSC-B, such as sending an INFO[INR] message to MSC-B. After receiving the handover request, MSC-B can The local switching release request judges whether the local switching can be released, and if it cannot be released, a message indicating rejection is returned to MSC-A, and MSC-A refuses to switch after receiving the message indicating rejection; Apply for port A resources, and return to MSC-A a confirmation message indicating successful application for port A resources, such as returning a local switching information confirmation message to MSC-A, wherein the local switching information confirmation message carries MSC-B to the mobile gateway After receiving the confirmation message, MSC-A applies for A port resources to the mobile gateway, notifies the base station controller to release the local switching, and performs subsequent handover processing, and carries the release command in the handover command sent to the source BSC. The instruction of the local switching, and the resource information of the A port applied by MSC-B, after the handover is completed, notify the MSC-B that the local switching has been released.

Of course, MSC-A can also send an INFO[INR] message to MSC-B after applying for A port resources from MGW, that is, MSC-A applies for A port resources to the mobile gateway, and only sends INFO if the application for A port resources is successful. [INR] message to MSC-B.

In addition, in addition to the above description that only one MSC, such as MSC-A, instructs the base station controller to release the local switching, MSCs of both parties, such as MSC-A and MSC-B, can also instruct the BSC to release the local switching. as follows:

MSC-A receives the handover request, and when it judges that local switching needs to be released according to the received handover request, it sends a local switching release request to MSC-B, such as sending an INFO[INR] message to MSC-B. The INFO[INR] message judges whether to allow the release of local switching. If it cannot be released, it will return a message of rejection to MSC-A. After receiving the message of rejection, MSC-A will refuse to switch; The gateway applies for A-port resources, and returns a local exchange release permission instruction to MSC-A (without carrying the applied A-port resource information), and MSC-A performs subsequent handover processing according to the local exchange release permission instruction, including applying for A-port to the mobile gateway. resources, and notify the base station controller to release the local switching. After the handover is completed, MSC-A sends a notification to MSC-B about the cancellation of the local switching, and MSC-B cancels the local switching according to the notification about the cancellation of the local switching, and returns a 200 OK[INF] message.

Of course, MSC-A can also send an INFO[INR] message to MSC-B after applying for A port resources from MGW, that is, MSC-A applies for A port resources to the mobile gateway, and only sends INFO if the application for A port resources is successful. [INR] message to MSC-B.

If the user has inter-office base station controller handover and needs to release the local exchange, the interaction between MSC-A and MSC-B is the same as the intra-office handover, which will not be described here. It should be noted that at this time, MSC-A Before switching, the permission of MSC-A and MSC-B must be obtained.

As can be seen from the above, in this embodiment, the exchange of local exchange information between MSCs is carried out through relay signaling, so that the MSC can perform local exchange processing according to the complete local exchange information (the local exchange information of the local party and the other party), In the MSC POOL network, even if the calling party and the called party are located on different MSCs, the MSCs where the calling party and the called party are located can also know the base station controller where the other party is calling, and can make a judgment to start the local switching in order to perform the local switching. Moreover, since the local switching information between MSCs can be transmitted through relay signaling, if a call is monitored on one of the MSCs, or the local switching cannot be started when performing operations such as announcements or supplementary services, the other The MSC can also learn, which is beneficial to the realization of local switching. Further, the use of relay signaling to transfer local exchange information between MSCs, compared with the use of MAP signaling to transfer local exchange information between MSCs, although more changes are required to MSC, but there is no need for HLR Make changes (using MAP signaling to transmit local exchange information between MSCs requires changes to MSC and HLR).

Embodiment four,

In order to better implement the above method, the embodiment of the present invention also provides a mobile switching center, MSC, as shown in FIG. 8 , the MSC includes an acquisition unit 401 and a processing unit 402;

The obtaining unit 401 is used to obtain the local switching information of the other party sent by the MSC called by the other party; The local switching information sent by the second calling party can specifically obtain the local switching information of the other party sent by the MSC called by the other party through MAP signaling or relay signaling, wherein the local switching information can include the information of the base station controller, such as the base station The signaling point information of the controller may also include information such as local switching capability information, and of course other information needed to establish and release local switching, such as Call-ID of a call and A-port bearer information. Among them, the signaling point information of the base station controller refers to the base station controller where a calling leg is located, and the local switching capability information refers to whether the call is being monitored, or whether it is performing operations such as playback and supplementary services.

The processing unit 402 is configured to perform local switching processing according to the local switching information of the own party and the local switching information of the other party acquired by the obtaining unit 401, that is, according to the local switching information of the first calling party and the local switching information of the second calling party The local switching information performs local switching processing, wherein the local switching information of the first calling party or the local switching information of the second calling party respectively include the information of the base station controller where the corresponding calling party is located.

Wherein, as shown in FIG. 8, the processing unit 402 may include a first judgment subunit 4021 and a notification subunit 4023;

The first judging subunit 4021 is used to judge whether the calls of both parties belong to the same base station controller according to the local switching information of the own party and the local switching information of the other party acquired by the obtaining unit 401, that is, according to the base station controller information of the first calling party Judging whether the calls of both parties belong to the same base station controller with the base station controller information of the second calling party obtained by the obtaining unit 401;

The notification subunit 4023 is used to notify the base station controller to start local switching when the first judging subunit 4021 determines that both calls belong to the same base station controller, and notify the mobile gateway to release the A port resources of the party, that is, the first calling party Port A resources.

Wherein, as shown in FIG. 8, the processing unit 402 may further include a second judging subunit 4022;

The second judging subunit 4022 is used to judge whether both parties have enabled the local switching information according to the local switching information of the party and the local switching information of the other party (the second calling party) acquired by the acquiring unit 401, that is, the local switching information of the second calling party. Ability to switch locally;

The obtaining unit 401 is further configured to obtain the local switching information of the second calling party when the local switching information of the first calling party or the local switching information of the second calling party respectively include the local switching capability information of the corresponding calling party. local exchange capability information;

The notification subunit 4023 is used to notify the base station controller to start the local switching when the first judging subunit 4021 determines that both calls belong to the same base station controller, and the second judging subunit 4022 determines that both parties have the ability to start local switching. exchange, and notify the mobile gateway to release the A port resources of the party, that is, the A port resources of the first calling party.

As shown in FIG. 8, the processing unit 402 may further include a first sending subunit 4024;

The first sending subunit 4024 is configured to send a local exchange establishment response message to the MSC called by the other party, such as the second mobile switching center, so that the MSC called by the other party, such as the second mobile switching center, notifies the mobile gateway to release the other party according to the local exchange establishment response message The A port resource of the second call is like the A port resource of the second call.

As shown in FIG. 8, the processing unit 402 may also include an application subunit 4025;

The application subunit 4025 is configured to apply to the mobile gateway for the A port resources of the party according to the local exchange information of the party and the local exchange information of the other party acquired by the acquisition unit 401, for example, according to the local exchange information of the first calling party and the acquisition unit The acquired local switching information of the second calling party applies to the mobile gateway for the A port resources of the party;

The first sending subunit 4024 is also used to send a local exchange release request to the MSC called by the other party, such as the second mobile switching center, after the application subunit 4025 successfully applies for the A port resources of the party, so that the MSC called by the other party such as The second mobile switching center applies to the mobile gateway for the A port resources of the other party according to the local switching release request, that is, the A port resources of the second calling party;

The notification subunit 4023 is further configured to notify the base station controller to cancel the local switching after receiving the confirmation message returned by the MSC called by the other party indicating that the A port resource of the other party (the second calling party) has been successfully applied.

As shown in FIG. 8, the processing unit 402 may further include a switching processing subunit 4026;

The handover processing subunit 4026 is configured to carry an indication of starting local switching in the handover request sent to the target MSC when the second judging subunit 4022 determines that both parties have the ability to start local switching, so that after the handover is completed, the target MSC Notify the mobile gateway to release its own A port resources and notify the base station controller to start the local switching according to the instruction indicating that the local switching is started, and then receive the handover response returned by the target mobile switching center indicating that the local switching is successfully started.

As shown in FIG. 8, the processing unit 402 may also be a second sending subunit 4027;

The second sending subunit 4027 is used to send the local exchange information of the own party and the local exchange information of the other party acquired by the acquisition unit 401 to the target MSC respectively (that is, the local exchange information of the own party and the local exchange information of the other party may not be sent at the same time ), so that the target MSC performs local switching processing according to the local switching information of its own party and the local switching information of the other party.

For the specific implementation of each of the above units, reference may be made to the foregoing embodiments, and details are not repeated here.

As can be seen from the above, the acquisition unit 401 of the MSC in this embodiment can acquire the local switching information of the other party sent by the MSC called by the other party, and then the processing unit 402 performs local switching processing according to the local switching information of the own party and the local switching information of the other party , so that in the MSC POOL network, even if the calling party and the called party are located on different MSCs, the MSCs where the calling party and the called party are located can also know the base station controller where the other party is calling, and can make a judgment to start local switching in order to perform local switching Moreover, since the obtaining unit 401 can obtain the local exchange information of the other party sent by the other party's MSC, if the call is monitored on one of the MSCs, or the local exchange cannot be started when performing operations such as announcements and supplementary services, the other The MSC can also learn, which is beneficial to the realization of local switching.

Embodiment five,

Correspondingly, the embodiment of the present invention also provides a communication system correspondingly, including any MSC provided in the embodiment of the present invention. As shown in FIG. 9, the communication system may specifically include a first mobile switching center (first MSC) 501 and a second mobile switching center (second MSC) 502;

The first mobile switching center 501 is used to obtain the local switching information of the second calling party sent by the second mobile switching center 502 when both calling parties are in the first mobile switching center 501 and the second mobile switching center 502 respectively, according to the The local switching information of the first calling party and the local switching information of the second calling party are processed for local switching, wherein the local switching information of the first calling party or the local switching information of the second calling party include corresponding Information about the base station controller where the calling party is located;

The second mobile switching center 502 is configured to send the local switching information of the other party to the first mobile switching center 501 .

The second mobile switching center 502 is further configured to send the local switching information of the second calling party to the first mobile switching center 501 through MAP signaling or relay signaling. Wherein, the local switching information may not only include base station controller information, such as base station controller signaling point information, but also include information such as local switching capability information, and of course, other information required to establish and release local switching , such as the Call-ID of the call and the bearer information of the A interface. Among them, the signaling point information of the base station controller refers to the base station controller where a calling leg is located, and the local switching capability information refers to whether the call is being monitored, or whether it is performing operations such as playback and supplementary services.

The interaction between the first mobile switching center 501 and the second mobile switching center 502 may refer to the foregoing embodiments for details, and details are not repeated here.

As can be seen from the above, the MSC in the communication system of this embodiment can obtain the local exchange information of the other party sent by the MSC called by the other party, and then perform local exchange processing according to the local exchange information of the party and the local exchange information of the other party, so that the MSC In the POOL network, even if the calling party and the called party are located on different MSCs, the MSCs where the calling party and the called party are located can also know the base station controller where the other party is calling, and can make a judgment to start the local switching in order to perform local switching processing, and , since the MSC can obtain the local exchange information sent by the other party's MSC, if the call is monitored on one of the MSCs, or the local exchange cannot be started when performing operations such as announcements or supplementary services, the other MSC can also know, Facilitate the realization of local exchange. Specifically, the local exchange information between MSCs can be transferred through MAP signaling or relay signaling (for detailed implementation, please refer to the previous embodiment two and embodiment three), and the local exchange information between MSCs can be transferred by using MAP signaling. When exchanging information, both the MSC and the HLR need to be modified, but the changes to the MSC are less. There are more changes to MSC. As for which way to transfer the local exchange information between MSCs, it can be selected according to the operator's strategy.

Those of ordinary skill in the art can understand that all or part of the steps in the various methods of the above-mentioned embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, and the storage medium can include: Read Only Memory (ROM, Read Only Memory), Random Access Memory (RAM, Random Access Memory), disk or CD, etc.

The implementation method, mobile switching center and communication system of a kind of local exchange provided by the embodiment of the present invention have been introduced in detail above. In this paper, specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments It is only used to help understand the method of the present invention and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation and scope of application. In summary, The contents of this description should not be construed as limiting the present invention.

Claims (22)

1. the implementation method of a local exchange is characterized in that, comprising:

When calling both sides during respectively in first mobile switching centre and second mobile switching centre, first mobile switching centre at first MPTY place obtains the local exchange message of second MPTY that second mobile switching centre sends;

First mobile switching centre is according to the local exchange message of first MPTY; And the local exchange message of second MPTY is carried out the processing of local exchange; Wherein, the local exchange message of the local exchange message of first MPTY or second MPTY comprises the information of the base station controller at place, respective call side respectively.

2. method according to claim 1 is characterized in that, the local exchange message that said first mobile switching centre obtains second MPTY of second mobile switching centre transmission comprises:

First mobile switching centre obtains the local exchange message of second mobile switching centre through second MPTY of MAP MAP signaling or the transmission of relaying signaling.

3. method according to claim 2 is characterized in that, said first mobile switching centre obtains before the local exchange message of second mobile switching centre through second MPTY of MAP signaling transmission, also comprises:

First mobile switching centre sends we's address and the international mobile subscriber identification code IMSI of this party call gives second mobile switching centre;

The local exchange message that said first mobile switching centre obtains second MPTY that second mobile switching centre sends through MAP MAP signaling comprises: the local exchange message of obtaining second MPTY that passes through the MAP signaling bear that second mobile switching centre sends according to the address of first mobile switching centre.

4. method according to claim 3 is characterized in that, through the local exchange message of MAP signaling bear is:

Expand the routing iinformation request SRI and the roaming number request PRN of existing MAP signaling or increase the MAP signaling newly and carry local exchange message.

5. method according to claim 2 is characterized in that, the local exchange message that said first mobile switching centre obtains second MPTY that second mobile switching centre sends through the relaying signaling comprises:

Through information request INR or the information INF cell of expansion with the call control protocol BICC message of bearer independent, perhaps expand the INR or the INF cell of ISUP isup message, perhaps newly-increased relaying signaling is carried local exchange message.

6. method according to claim 1 is characterized in that, said first mobile switching centre is according to the local exchange message of first MPTY, and the processing that the local exchange message of second MPTY is carried out local exchange comprises:

First mobile switching centre confirms that based on the base station controller information of we's the base station controller information and second MPTY both sides call out when belonging to same base station controller; Notify said base station controller to start local exchange, and the notice mobile gateway discharge we's A mouth resource.

7. method according to claim 6 is characterized in that, said base station controller information is the information of base station controller signalling point;

Then first mobile switching centre confirms according to the information of the base station controller signalling point of the information of we's base station controller signalling point and second MPTY that both sides call out and whether belongs to same base station controller.

8. method according to claim 1 is characterized in that, the local exchange message of said first MPTY or the local exchange message of second MPTY also comprise following combination in any respectively:

The local exchanging capability information of respective call side;

The call identification Call-ID of respective call side;

The A mouthpiece of respective call side carries information.

9. method according to claim 8; It is characterized in that; When the local exchange message of the local exchange message of first MPTY or second MPTY also comprises the local exchanging capability information of said respective call side respectively; Said first mobile switching centre is according to the local exchange message of first MPTY, and the processing that the local exchange message of said second MPTY is carried out local exchange comprises:

First mobile switching centre confirms according to the base station controller signalling point information of we's the base station controller signalling point information and second mobile switching centre that both sides call out and belongs to same base station controller; And when confirming that according to the local exchanging capability information of local exchanging capability information and second MPTY of self both sides possess the ability that starts local exchange; Notify said base station controller to start local exchange, and the notice mobile gateway discharge the A mouth resource of said second MPTY.

10. method according to claim 6 is characterized in that, after the notice mobile gateway discharges our A mouth resource, also comprises:

Send local exchange and set up response message, so that second mobile switching centre sets up the A mouth resource that response message notice mobile gateway discharges second MPTY based on this this locality exchange to second mobile switching centre.

11. based on claim 6 or 9 described methods, it is characterized in that, after this locality exchange is set up, also comprise:

First mobile switching centre is based on the local exchange message of we's the local exchange message and second MPTY A mouth resource to mobile gateway application we;

When application we's A mouth resource success, the local exchange of transmission is removed request to second mobile switching centre, so that second mobile switching centre removes the A mouth resource of request to mobile gateway application second MPTY according to this this locality exchange;

Receiving after expression that second mobile switching centre returns successfully applied for the affirmation message of A mouth resource of second MPTY, the informing base station controller is removed local exchange.

12. method according to claim 6 is characterized in that, said method also comprises:

Second mobile switching centre obtains the local exchange message of first MPTY of first mobile switching centre transmission;

Second mobile switching centre confirms based on the base station controller signalling point information of we's the base station controller signalling point information and first MPTY that both sides call out and belongs to same base station controller; Notify said base station controller to start local exchange, and the notice mobile gateway discharge we's A mouth resource.

13. based on the described method of claim 12, it is characterized in that, after this locality exchange is set up, also comprise:

Second mobile switching centre is based on the local exchange message of we's the local exchange message and first MPTY A mouth resource to mobile gateway application we;

When application we's A mouth resource success, the local exchange of transmission is removed request to first mobile switching centre, so that first mobile switching centre removes the A mouth resource of request to mobile gateway application first MPTY according to this this locality exchange;

Receiving after expression that first mobile switching centre returns successfully applied for the affirmation message of A mouth resource of first MPTY, the informing base station controller is removed local exchange.

14. according to claim 6 or 9 or 12 described methods, it is characterized in that, when inter-office switchover takes place, also comprise:

First mobile switching centre or second mobile switching centre confirm that according to we's the local exchanging capability information and the local exchanging capability information of second MPTY both sides possess the ability that starts local exchange; Then in the handoff request that sends to target mobile switching centre, carry expression and start the local indication that exchanges; So that after switch accomplishing, A mouth resource and informing base station controller that the indication notice mobile gateway that target mobile switching centre starts local exchange according to this expression discharges the corresponding MPTY of said target mobile switching centre start local the exchange;

The local handoff response that successfully starts that exchanges of the expression that receiving target mobile switching centre returns.

15. a mobile switching centre is characterized in that, comprising:

Acquiring unit is used for when calling both sides during respectively in this mobile switching centre and second mobile switching centre, obtains the local exchange message of second MPTY that second mobile switching centre sends;

Processing unit; Be used for local exchange message according to first MPTY; And the local exchange message of said second MPTY is carried out the processing of local exchange; Wherein, the local exchange message of the local exchange message of said first MPTY or second MPTY comprises the information of the base station controller at place, respective call side respectively.

16. mobile switching centre according to claim 15 is characterized in that, said processing unit comprises:

First judgment sub-unit, the base station controller information that is used for second MPTY that base station controller information and said acquiring unit according to first MPTY get access to are judged that both sides call out and whether are belonged to same base station controller;

The notice subelement is used for confirming both sides when said first judgment sub-unit and calls out when belonging to same base station controller, and the informing base station controller starts local exchange, and the notice mobile gateway discharges our A mouth resource.

17. mobile switching centre according to claim 16; It is characterized in that; Said acquiring unit; Also be used for when the local exchange message of the local exchange message of first MPTY or second MPTY also comprises the local exchanging capability information of said respective call side respectively, obtaining the local exchanging capability information of said second MPTY;

Said processing unit also comprises:

Second judgment sub-unit, the local exchanging capability information that is used for second MPTY that local exchanging capability information and said acquiring unit according to we get access to judges whether both sides all possess the ability that starts local exchange;

Said notice subelement also is used for when said second judgment sub-unit judges that both sides possess the ability that starts local exchange, and the informing base station controller starts local exchange, and the notice mobile gateway discharges we's A mouth resource.

18. mobile switching centre according to claim 16 is characterized in that, said processing unit also comprises:

First sends subelement, is used to send local exchange and sets up response message to second mobile switching centre, so that second mobile switching centre sets up the A mouth resource that response message notice mobile gateway discharges second MPTY based on this this locality exchange.

19. mobile switching centre according to claim 17 is characterized in that, said processing unit also comprises:

The application subelement, the local exchange message that is used for second MPTY that local exchange message and acquiring unit according to first MPTY get access to is to the our A mouth resource of mobile gateway application;

First sends subelement; Be used for after application subelement application we's A mouth resource success; Send local exchange releasing request and give second mobile switching centre, so that second mobile switching centre removes the A mouth resource of asking to mobile gateway application second MPTY according to this this locality exchange;

Said notice subelement also is used for receiving after expression that second mobile switching centre returns successfully applied for the affirmation message of A mouth resource of second MPTY, and the informing base station controller is removed local exchange.

20. mobile switching centre according to claim 19; It is characterized in that; Said processing unit also comprises: the hand-off process subelement; Be used for when second judgment sub-unit confirms that both sides possess the ability that starts local exchange, in the handoff request that sends to target mobile switching centre, carrying the indication of representing to start local exchange, so that after switching completion; A mouth resource and informing base station controller that indication notice mobile gateway that target mobile switching centre starts local exchange according to this expression discharges we start local exchange, then the local successfully handoff response of startup that exchange of expression returned of receiving target mobile switching centre.

21. a communication system is characterized in that, comprises first mobile switching centre and second mobile switching centre;

Said first mobile switching centre; Be used for when calling both sides during respectively in first mobile switching centre and second mobile switching centre; Obtain the local exchange message of second MPTY of second mobile switching centre transmission; Local exchange message according to first MPTY; And the local exchange message of said second MPTY carries out the processing of local exchange, and wherein, the local exchange message of said first MPTY or the local exchange message of second MPTY comprise the information of the base station controller at place, respective call side respectively;

Said second mobile switching centre, the local exchange message that is used to send we is to first mobile switching centre.

22. communication system according to claim 21 is characterized in that,

Said second mobile switching centre, the local exchange message that is used for sending second MPTY through MAP MAP signaling or relaying signaling is to first mobile switching centre.

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