WO2009121310A1

WO2009121310A1 - Method, system and device for selecting a gateway

Info

Publication number: WO2009121310A1
Application number: PCT/CN2009/071160
Authority: WO
Inventors: 王鹏
Original assignee: 华为技术有限公司
Priority date: 2008-04-03
Filing date: 2009-04-03
Publication date: 2009-10-08
Also published as: CN101553042B; CN101553042A

Abstract

A method, system and device for selecting a gateway are provided in the embodiment of the invention. The method includes: the second mobile switch central server MSC-S receives a message which bears a gateway identifier and gateway media information of the first gateway hold by the first MSC-S and is sent by the first MSC-S; when the second MSC-S can use the first gateway to provide a service, a bearer is established by using the first gateway according to the gateway media information. In the embodiment of the invention, it can be realized that several MSC-Ss hold the same media gateway, optimizing bearer path can be realized.

Description

Method, system and device for gateway selection This application claims to be submitted to the Chinese Patent Office on April 3, 2008, the application number is 200810089724.2, and the Chinese patent application titled "a gateway selection method, system and device" is preferred. The entire contents of which are incorporated herein by reference. Technical field

The embodiments of the present invention relate to the field of communications technologies, and in particular, to a method, system, and device for gateway selection. Background technique

The core network of WCDMA (Wideband Code Division Multiple Access) evolves from the R99 circuit mode to the packet-based softswitch, and is divided into R4 BICN (Bearer Independent Core Network) and R5 IMS (IP). Based on Multimedia Subsystem (IP-based Multimedia Subsystem), R4 BICN is based on BICC (Bearer Independent Call Control) and H.248 protocol, and is designed to packetize WCDMA CS (Circuit Switch). The domain, which saves the overall cost of voice services, is currently defined by the 3GPP (The 3rd Generation Partnership Project), which is based on SIP-I (Session Initiation Protocol with Integrated Services Digital Network User Part encapsulation). The business digital network user part) and the H.248 protocol-based technology.

In the basic call service, each MSC-S (Mobile Switch Central Server) will occupy the gateway resources to establish the bearer required for the call service, and the MSC-S can be based on the call setup and progress. The business needs to control the call and bearer. The multiple MSC-Ss through which the call passes may occupy different gateways for the establishment of bearers. In practical applications, the problem of wasted gateway resources was wasted, and the bearer path was long, which caused the service quality to be degraded. Based on the basic call setup process, as shown in FIG. 1 , a flow chart of a method for bearer establishment based on gateway negotiation and based on negotiation result in the prior art includes the following main steps:

Step 101: The calling MSC-S selects an available gateway in advance, and then transmits the multimedia gateway identifier MGW-ID (Media Gateway Identifier, or may also be referred to as a bearer control unit identifier BCU-ID (Bearer Control) through the SIP-I signaling message. Unit Identifier)) In the message to the called MSC-S, the message indicating that the calling MSC-S does not complete the actual occupation of the bearer plane.

Step 102: The called MSC-S confirms whether the call can be established by using the gateway selected by the calling MSC-S according to the gateway identifier provided by the calling MSC-S, and if so, the gateway source is occupied. After the called MSC-S completes the gateway resource occupation, it returns the gateway identifier and the bearer attribute to the calling MSC-S. After the called MSC-S occupies, the gateway identifier may be consistent with the gateway identifier provided by the calling MSC-S. It may also be inconsistent; bearer attributes include RTP (Real Time Protocol) addresses, ports, available codec lists, and so on.

Step 103: The calling MSC-S occupies resources of the gateway corresponding to the gateway identifier. If the gateway connection call provided by the called MSC-S can be used, the resources of the gateway are occupied, otherwise the gateway or other gateway selected in step 101 can continue to be occupied. After the completion of the gateway resource occupation, the calling MSC-S provides the SDP provision in the response mechanism through a new round of SDP (Session Description Protocol) by carrying the attributes (including the RTP address, port, available codec list, etc.). SDP Offer) is sent to the called MSC-S.

Step 104: The called MSC-S returns to the calling MSC-S a response to the SDP to complete the SDP negotiation and bearer establishment.

The inventors have found that at least the following problems exist in the prior art:

In the prior art, the initiation of the bearer setup and the gateway identity interaction are performed separately, and multiple SDP message interactions are required. The MSC-S needs to process the SDP multiple times, so that the complex call setup process takes a long time. In addition, there is currently no way to implement the delivery and negotiation of gateway identifiers. Summary of the invention

Embodiments of the present invention provide a method, system, and device for gateway selection, to implement an optimized setup process of a bearer and to implement delivery of a gateway identifier between MSC-S.

The embodiment of the invention provides a method for gateway selection, including:

The second mobile switching center server MSC-S receives the message that the first MSC-S sends the gateway identifier and the gateway media information of the first gateway occupied by the first MSC-S; when the second MSC-S can use When the first gateway provides a service, the first gateway is used to establish a bearer according to the gateway media information.

The embodiment of the invention further provides a system for gateway selection, including:

a first mobile switching center server MSC-S, configured to send, to the second MSC-S, a message carrying the gateway identifier and gateway media information of the first gateway occupied by the first MSC-S; Receiving, by the first MSC-S, carrying the first

a message of the gateway identifier and the gateway media information of the first gateway that is occupied by the MSC-S. When the second MSC-S can provide the service by using the first gateway, the first gateway is used to establish a bearer according to the gateway media information. .

The embodiment of the present invention further provides a second mobile switching center server MSC-S, which includes:

a second receiving unit, configured to receive, by the first MSC-S, a message that carries the gateway identifier of the first gateway and the gateway media information;

And a second processing unit, configured to: when the first gateway is used to provide services, use the first gateway to establish a bearer according to the gateway media information.

The embodiment of the present invention further provides a first mobile switching center server MSC-S, which includes:

The first sending unit is configured to send, to the second MSC-S, a message carrying the gateway identifier and the gateway media information of the first gateway occupied by the first MSC-S.

In the embodiment of the present invention, multiple MSC-Ss can occupy the same media gateway to implement the optimization of the bearer path and implement the transfer of the gateway identifier between the MSC-S. DRAWINGS

1 is a flow chart of a method for establishing a bearer based on gateway negotiation and based on a negotiation result in the prior art;

2 is a flowchart of a method for gateway selection according to Embodiment 1 of the present invention;

3 is a flowchart of a method for gateway selection in Embodiment 2 of the present invention;

FIG. 4 is a structural diagram of a system for gateway selection in an embodiment of the present invention. detailed description

A first embodiment of the present invention provides a gateway selection method. As shown in FIG. 2, the method includes: Step 201: The first MSC-S preselects an available first gateway and completes occupation of the bearer.

Step 202: The first MSC-S transmits the gateway identifier BCU-ID of the first gateway and the bearer information (including the RTP address, the port, the available codec list, and the like) to the second MSC-S through the SIP-I signaling message, specifically The bearer information is gateway bearer information, that is, gateway media information.

Step 203: The second MSC-S selects an available second gateway and completes the occupation of the bearer. The method for selecting the second gateway is to confirm, according to the gateway identifier provided by the first MSC-S, whether the gateway can be established by using the gateway selected by the first MSC-S, and if so, the second gateway and the first gateway are the same gateway; otherwise, Then select other available gateways and occupy the gateway resources (ie, the second gateway and the first gateway are different gateways).

Step 204: After the second MSC-S completes the gateway resource occupation, the gateway identifier and the load attribute (including the RTP address, the port, the available codec list, and the like) are returned to the first MSC-S. Specifically, the bearer attribute is a gateway bearer. Information, ie gateway media information; the gateway identity further optionally includes an identity of the second gateway.

After the second MSC-S completes the gateway resource occupation, the gateway bearer information (including the RTP address, the port, the available codec list, and the like) is returned to the first MSC-S, and the identifier of the second gateway is not carried.

Step 205: The first MSC-S modifies the remote media attribute of the first gateway to complete the bearer set up.

After the second MSC-S completes the gateway resource occupation, the gateway identifier and the load attribute (including the RTP address, the port, the available codec list, and the like) are returned to the first MSC-S. Specifically, the bearer attribute is the gateway bearer information, that is, Gateway media information. Then, the first MSC-S may modify the establishment of the remote media attribute completion bearer of the first gateway.

In the first embodiment of the present invention, the same MSC can select any one of the multiple gateways to establish a bearer required for the call. In the first embodiment of the present invention, it is expected that the two MSCs can establish a call by using the same MGW. The gateway selected by the first MSC cannot be used by the second MSC, and the first MSC and the second MSC establish a bearer to transmit the information to the second MSC, and when the second MSC cannot use the gateway selected by the first MSC to establish the bearer, , other available gateways of the first MSC can be used. In order to increase the purpose of the two MSCs using the same MGW, the first MSC needs to determine a gateway that the second MSC can also use when selecting the first gateway before the gateway negotiation.

A second embodiment of the present invention provides a gateway selection method. As shown in FIG. 3, the following main steps are included:

Step 301, in order to implement the optimized setup process of the bearer, the first MSC-S (calling MSC-S) receives the call setup request (such as the SETUP sent by the UE, or the call setup request sent by the external network or other MSC-S). The available first media gateway MGW is selected to interact with the MGW and occupy the media gateway resource of the called network.

Step 302: The first MSC-S sends a SIP message (such as an INVITE request message) to the second MSC-S (the called MSC-S), where the message carries the gateway identifier BCU-ID of the media gateway and the bearer of the occupied gateway resource. Information (ie gateway media information, including RTP addresses, ports, available codec lists, etc.). Further, the first MSC-S may carry, in the message, a gateway identifier of the gateway that the first MSC-S other than the first MGW can use for the call.

Step 303: The second MSC-S selects an available second gateway and completes the occupation of the bearer.

The method for selecting the second gateway is that the second MSC-S preferentially selects the first MSC-S. The gateway corresponding to the first gateway identifier that can be used for the current call is used as the second gateway. Specifically, the second MSC-S confirms whether the call can be established by using the first MSC-S selected gateway according to the first gateway identifier provided by the first MSC-S, and if so, uses the first gateway to establish the bearer according to the gateway media information. And returning the second gateway identifier, where the second gateway identifier is the same gateway identifier as the first gateway identifier, and the second gateway and the first gateway are the same gateway; otherwise, according to the first gateway identifier provided by the first MSC-S The gateway identifier of the other gateways outside confirms whether other gateways available to the first MSC-S can be used, and if so, the gateway is selected as the second gateway; otherwise, the other second MSC-S can be selected for the gateway of the call.

The second MSC-S allocates and occupies gateway resources;

Step 304: The second MSC-S returns, to the first MSC-S, the gateway identifier of the gateway occupied by the second MSC-S and the gateway resource by using a SIP message (such as a 183 temporary response message to the INVITE request or other temporary response message). Bearer information (ie gateway media information, including RTP address, port, available codec list, etc.). Further, the second MSC-S may return the identifier of the other gateways in the second MSC-S that can be used for the call, in addition to the identifier of the second gateway to the first MSC-S.

Step 305: After receiving the message corresponding to the step 304, if the first gateway and the second gateway are different gateways, the first MSC-S may continue to use the first gateway, or release the gateway resources already occupied by the first gateway. Reselect, allocate, and consume resources from another gateway. The reselection gateway is:

For example, the first MSC-S may use the second gateway occupied by the second MSC-S, and the first MSC-S selects the second gateway as the first gateway; otherwise:

If the first MSC-S can use a gateway other than the second gateway provided by the second MSC-S, the gateway is selected as the first gateway; otherwise

Then select the other first MSC-S can be used for the gateway of the call.

If the first MSC-S reselects the first gateway, the first gateway resource is allocated and occupied. Further includes the following steps:

Step 306: The first MSC-S sends a SIP message (such as an UPDATE request message) to the second MSC-S (called MSC-S), where the message carries the re-selected gateway identifier of the first gateway. Know BCU-ID and bearer information of gateway resources (ie gateway media information, including RTP address, port, available codec list, etc.).

Step 307: If the first gateway identified by the first MSC-S in step 306 identifies the gateway corresponding to the BCU-ID and the second gateway occupied by the second MSC-S is not the same gateway, and the second MSC-S may The gateway reselected by the first MSC-S is used, and during the call setup and progress, the MSC-S can control the call and bearer according to the service requirements. The multiple MSC-Ss through which the call passes may occupy different gateways for the establishment of bearers. The newly selected first gateway establishes a call, and the second MSC-S may reselect the first gateway reselected by the first MSC-S, allocate and occupy the reselected second gateway resource, and perform steps 308 and 309.

Step 308: The second MSC-S returns the bearer information of the re-occupied second gateway to the first MSC-S.

Step 309: After receiving the message corresponding to step 308, the first MSC-S updates the remote bearer information to the first gateway (not shown in this step).

Those skilled in the art can derive some business processes including, but not limited to, the following main steps and SIP-I based 3GPP CS network related technologies:

1. The first MSC-S accesses the MSC-S (VMSC) to provide services to the called user, and the second MSC-S accesses the MSC-S (VMSC) or the gateway MSC that provides services for the called user. -S (Gateway Mobile Switch Central Server, GMSC);

2. The first MSC-S is the gateway MSC-S (GMSC), and the second MSC-S is the access MSC-S (VMSC) or other gateway MSC-S (GMSC) that provides services to the called subscriber.

Implementation of the technical method in the embodiments of the present invention requires the ability to pass the gateway identity BCU-ID between the MSC-S and the gateway used to negotiate the call.

The embodiment of the invention provides a method for transmitting a gateway identifier, including:

The second mobile switching center server receives the SDP or SIP message sent by the first mobile switching center server and carries the gateway identifier of the first gateway occupied by the first mobile switching center server; the second mobile switching center server returns to the first mobile switching center server The SDP or SIP message identified by the gateway of the second gateway. The user name or unicast address parameter of the SDP may be used to carry the gateway identifier, i=row, s=row or carry the gateway identifier through the SDP attribute parameter &= line; or use the SIP header field to carry the gateway identifier; or The SIP message body carries the gateway identifier. The SIP message body can adopt the ABNF (Augmented Backus - Naur Form) encoding method, the XML (Extensible Markup Language) encoding method, or other encoding methods.

The SIP protocol uses SDP for media negotiation of sessions, and the SIP-I based 3GPP CS network uses SDP for media negotiation of sessions and establishment of bearers. The SDP protocol has the characteristics of a single ticket and has been widely used in the field of communication. At the same time, SDP has the characteristics of easy expansion, and entities that do not support SDP extension can ignore unrecognized extensions without affecting the establishment of basic sessions. Therefore, proper extension and definition of the SDP protocol can implement gateway identity delivery and negotiation.

Based on the SDP delivery gateway identifier BCU-ID and the gateway used for negotiating the call, step 202 in the method based on the gateway negotiation and the bearer establishment based on the negotiation result, step 202 in the method of performing gateway negotiation and loading establishment Step 302, step 304, step 306, and step 308 in the implementation of step 204 and the implementation of the present invention may adopt any one of the following implementation methods 1-8:

1. The username (username) parameter of the S= o= line is used to pass the SDP sender's username information. In the multicast-based multimedia session, the SDP receiver can help the SDP receiver to decide whether to join the multimedia session. This parameter is not used in non-multicast multimedia session services or systems (especially SIP-I based 3GPP CS networks). In this way, there is no need to add new parameters, fewer changes to the protocol, and more convenient implementation. At the same time, because it does not occupy parameters that affect the service processing, it will not have any impact on SIP applications that do not use MGW-ID. The BCU-ID is carried by the username (username) parameter of the o= line of the SDP. Such as:

V=0

o=BCU-ID:mgwl .orig-cs.net;mgw2. orig-cs.net 98789736 90842807 IN IP4 mscl .orig-cs.net

s=- c=IN IP4 192.168.1.2 t=0 0

m=audio 49170 RTP/AVP 0

Where ₀ ) the _{username of the} line starts with "BCU-ID:" to indicate that the rest of the parameter is BCU-ID, or the content of this parameter can be expressed as BCU-ID in the manner agreed by MSC-S without "BCU" -ID: "Start tag. Such as o = behavior:

o=mgwl.orig-cs.net;mgw2. orig-cs.net 98789736 90842807 IN IP4 mscl.orig-cs.net

When carrying multiple BCU-IDs, the BCU-IDs are separated by ";" or other means. 2. The unicast-address parameter of the SDP o= line is used to pass the address information of the SDP sender. In the multicast-based multimedia session, the SDP receiver can help the SDP receiver decide whether to join the multimedia session. This parameter is not used in non-multicast multimedia session services or systems (especially SIP-I based 3GPP CS networks). In this way, there is no need to add new parameters, fewer changes to the protocol, and more convenient implementation. At the same time, because it does not occupy parameters that affect the service processing, it will not have any impact on the SIP application that does not use the MGW-ID. The BCU-ID is carried by the unicast-address (unicast address) parameter of the o= line of the SDP. Such as: v=0

o=- 3498789736 2890842807 IN IP4 mgwl.orig-cs.net s=- c=IN IP4 192.168.1.2

t=0 0

m=audio 49170 RTP/AVP 0

3. The 8= line of the SDP is used to convey the topic information of the session, and the multicast-based multimedia session can help the SDP recipient decide whether to join the multimedia session. This parameter is not used in non-multicast multimedia session services or systems (especially SIP-I based 3GPP CS networks). In this way, there is no need to add new parameters, fewer changes to the protocol, and more convenient implementation. At the same time, because it does not occupy parameters that have an impact on service processing, it will not have any impact on SIP applications that do not use MGW-ID. Carry the BCU-ID through the 8= line of 80?. Such as: V=0

o=- 3498789736 2890842807 IN IP4 192.168.1.2 s=BCU-ID: mgwl.orig-cs.net; mgw2.orig-cs.net c=IN IP4 192.168.1.2

t=0 0

m=audio 49170 RTP/AVP 0

The s= line starts with "BCU-ID:" to indicate that the rest of the parameter is BCU-ID, or the content of this parameter can be expressed as BCU-ID in the manner agreed by MSC-S without "BCU-ID". :" Start tag. Such as 8 = behavior:

s=mgwl. orig-cs.net; mgw2.orig-cs.net

When carrying multiple BCU-IDs, the BCU-IDs are separated by ";" or other means.

4, 80? The 1= line is used to deliver additional text information for the session, which can help the SDP recipient decide whether to join the multimedia session in a multicast-based multimedia session. This parameter is not used in non-multicast multimedia session services or systems (especially SIP-I based 3GPP CS networks). In this way, there is no need to add new parameters, fewer changes to the protocol, and more convenient implementation. At the same time, because it does not occupy parameters that affect the service processing, it will not have any impact on SIP applications that do not use MGW-ID. Carry the BCU-ID through the 1= line of 80. Such as: v=0

o=- 3498789736 2890842807 IN IP4 192.168.1.2 s=- i=BCU-ID: mgwl.orig-cs.net, mgw2.orig-cs.net c=IN IP4 192.168.1.2

t=0 0

m=audio 49170 RTP/AVP 0

Where i=row starts with "BCU-ID:" to indicate that the rest of the parameter is BCU-ID, or you can use the way agreed by MSC-S to indicate that all the contents of this parameter are BCU-ID without "BCU-ID". :" Start tag. Such as 1 = behavior:

i=mgw Lorig-cs.net; mgw2.orig-cs.net BCU-IDs are separated by ";" or other means when carrying multiple BCU-IDs.

5, 80? The &= line is used for various attribute information of the session or media, and each attribute information is identified by the attribute name. In this way, because it does not occupy parameters that affect business processing, it does not have any impact on SIP applications that do not use MGW-ID. The BCU-ID is passed through the SDP attribute parameter a= line carrying the BCU-ID attribute. Such as:

V=0

o=- 3498789736 2890842807 IN IP4 192.168.1.2 s=- a=BCU-ID: mgwl.orig-cs.net, mgw2.orig-cs.net c=IN IP4 192.168.1.2

t=0 0

m=audio 49170 RTP/AVP 0

The SIP-I-based 3GPP CS network uses the SIP protocol to perform call, session, and service control functions such as session establishment, modification, and termination. The SIP protocol has the characteristics of easy extension, and the SIP entity ignores the unsupported SIP header field and the message body does not affect the basic SIP call and session control functions. Therefore, proper extension and definition of the SIP protocol can implement gateway identification delivery and negotiation. In this way, because it does not occupy parameters that affect the processing of the service, it does not have any impact on the SIP application that does not use the MGW-ID.

6. Carrying through the SIP header field, for example, the following header field is included in the SIP message:

BCU-ID: mgwl.orig-cs.net, mgw2.orig-cs.net

7. Carrying by the SIP message body, wherein the message body uses ABNF coding, for example, the SIP message includes the following header field indicating the message body type:

Content-Type: application/available-BCU-ID

And the corresponding message body such as:

Mgwl.orig-cs.net

Mgw2.orig-cs.net 8. Carrying by the SIP message body, wherein the message body uses the XML encoding method, for example, the SIP message includes the following header field indicating the message body type:

Content-Type: application/available-BCU-ID+xml and the corresponding message body such as:

<available-mgw>

</available-mgw>

It is assumed that the first MSC-S can use the mgwl.orig-cs.net and the mgw2.orig-cs.net to establish the call bearer, and further occupies the first MSC-S in the first embodiment of the present invention and the second embodiment of the present invention. The gateway identified as mgwl.orig-cs.net is used to establish the call 7 load.

Step 101 and step 102 of the method for performing bearer establishment based on the gateway negotiation and the result of the negotiation based on the foregoing method, if the method of the above 1~5 is adopted, the SDP does not include the information, and the m= line in the corresponding SDP is:

m=audio 0 RTP/AVP 0

Indicates that the bearer information is temporarily unavailable, or 0= the line is:

c=IN IP4 0.0.0.0

Indicates that bearer information is temporarily unavailable, or other means that bearer information is temporarily unavailable.

^ The second MSC-S can use mgwl.term-cs.net and mgw2.term-cs.net to establish the call 7 load, while mgwl.term-cs.net and mgwl.orig-cs.net are the same gateway. The different identifiers, the gateway information in the step 101 in the method for performing bearer establishment based on the gateway negotiation and the negotiation result, the step 202 in the first embodiment of the present invention, and the gateway information in the step 302 and the step 306 in the implementation of the present invention The delivery method is any one of the foregoing 1 to 8 modes, and according to the foregoing gateway identifier transmission method, the step 102 in the method of performing bearer establishment based on the gateway negotiation and the negotiation result, the step 204 and the present in the first embodiment of the present invention The gateway information in step 304 and step 308 in the second embodiment of the present invention may be corresponding contents in the following: 1, 8 to 8, respectively: 1. Carry the BCU-ID through the username (username) parameter of the o= line of the SDP. Such as: v=0

o=BCU-ID: mgw 1.term-cs.net;mgw2. term-cs.net 98789736 90842807 IN IP4 mscl.term-cs.net

s=- c=IN IP4 192.168.10.2

t=0 0

m=audio 10000 RTP/AVP 0

2. Carry the BCU-ID through the unicast-address (unicast address) parameter of the o= line of the SDP. Such as:

V=0

o=BCU-ID: mgwl.term-cs.net;mgw2.term-cs.net 98789736 90842807 IN IP4 mscl.term-cs.net

s=- c=IN IP4 192.168.10.2

t=0 0

m=audio 10000 RTP/AVP 0

3. Carry the BCU-ID through s=# of SDP. Such as:

V=0

o=- 98789736 90842807 IN IP4 192.168.1.2

s=BCU-ID: mgwl.term-cs.net; mgw2.term-cs.net c=IN IP4 192.168.10.2

t=0 0

m=audio 10000 RTP/AVP 0

4, Carry the BCU-ID through the 1= line of 80. Such as:

V=0 o=- 98789736 90842807 IN IP4 192.168.1.2 s=- i=BCU-ID: mgwl.term-cs.net, mgw2.term-cs.net c=IN IP4 192.168.10.2

t=0 0

m=audio 10000 RTP/AVP 0

5, Carry the BCU-ID through the attribute parameter a= of the SDP. Such as:

V=0

o=- 98789736 90842807 IN IP4 192.168.1.2

s=- a=BCU-ID: mgwl.term-cs.net, mgw2.term-cs.net c=IN IP4 192.168.10.2

t=0 0

m=audio 10000 RTP/AVP 0

BCU-ID: mgwl.term-cs.net, mgw2.term-cs.net

7. The bearer is carried by the SIP message body, where the message body uses the ABNF code, for example, the SIP message includes a header field indicating the message body type as follows:

Content-Type: application/available-BCU-ID

And the corresponding message body such as:

Mgwl.term-cs.net

Mgw2.term-cs.net

8', carried by the SIP message body, wherein the message body uses XML coding mode, for example, the SIP message includes a header field indicating the message body type as follows:

<available-mgw>

</available-mgw>

For example, the first MSC-S and the second MSC-S use the same identifier for the same MGW (for example, mgwl.term-cs.net shown in 1,8, also uses mgwl.orig-cs.net) The first MSC-S and the second MSC-S do not need to determine the local corresponding gateway identifier according to the BCU-ID transmitted from the peer end. The above implementation method is also more simple. The corresponding mgwl.term-cs.net shown in 1,~8, only needs to be replaced by mgwl.orig-cs.net.

The embodiment of the present invention provides a gateway selection system, as shown in FIG. 4, including: a first mobile switching center server MSC-S 100, configured to send to the second MSC-S 200 to carry the first MSC-S 100 occupation The gateway of the first gateway and the message of the gateway media information.

The second MSC-S 200 is configured to receive, by the first MSC-S 100, a message that carries the gateway identifier of the first gateway and the gateway media information; when the service can be provided by using the first gateway, the first information is used according to the gateway media information. The gateway establishes a bearer and returns a second gateway identifier, where the second gateway identifier is an identifier of the same gateway as the first gateway identifier.

The second MSC-S 200 is further configured to receive, by the first MSC-S 100, a gateway identifier of a gateway that is used by the first MSC-S 100 other than the first gateway to be used for the call, when the second MSC-S When the first gateway occupied by the first MSC-S 100 cannot be used, the gateway corresponding to the gateway identifier that the other first MSC-S 100 can use for the call is used.

When the second MSC-S 200 cannot use the first gateway to provide services, the other gateway is selected as the second gateway, and the second MSC-S 200 is further configured to return the gateway identifier and the gateway of the second gateway to the first MSC-S 100. Media information message.

The second MSC-S 200 is also used to return to the first MSC-S 100 the gateway identity of the gateway that the other second MSC-S 200 can use for the call.

The first MSC-S 100 is further configured to: after receiving the identifier of the second gateway, determine whether the Providing a service by using the second gateway, releasing the occupation of the first gateway if possible, and re-using the second gateway to establish a bearer according to the gateway media information; when the first MSC-S 100 cannot use the second gateway, and the second MSC-S 200 When the first MSC-S 100 returns to the gateway identifier of the gateway of the other MSC-S 200 in addition to the identity of the second gateway, if the first MSC-S 100 can use the second MSC- The gateway other than the second gateway provided by the S200 reselects the gateway as the first gateway.

The second mobile switching center server MSC-S 200 specifically includes:

The second receiving unit 210 is configured to receive a message that is sent by another MSC-S and carries the gateway identifier of the first gateway and the gateway media information.

The second processing unit 220 is configured to: when the service is provided by using the first gateway, establish a bearer by using the first gateway according to the gateway media information.

The second receiving unit 210 is further configured to receive, by using the message sent by the first MSC-S 100, the gateway identifier of the gateway that the first MSC-S 100 other than the first gateway can use for the call.

The second MSC-S 200 also includes:

The second sending unit 230 is configured to return the second gateway identifier to the first MSC-S 100, where the second gateway identifies the identifier that is the same gateway as the first gateway identifier.

Preferably, the second processing unit 220 is further configured to select another gateway as the second gateway when the second MSC-S 200 cannot use the first gateway to provide services.

The second sending unit 230 is further configured to: when the second processing unit 220 selects another gateway as the second gateway, return a message of the gateway identifier of the second gateway and the gateway media information to the first MSC-S 100.

When the second MSC-S 200 can not use the first gateway to provide services, when the other gateway is selected as the second gateway, the second processing unit 220 is further configured to preferentially select the first gateway sent by the first MSC-S 100. The other first MSC-S 100 can be used for the gateway corresponding to the gateway identity of the current call.

The second sending unit 230 is further configured to return, to the first MSC-S 100, an identifier of the gateway that the other second MSC-S 200 can use for the call, in addition to the identifier of the second gateway. The first MSC-S 100 specifically includes:

The first sending unit 110 is configured to send, to the second MSC-S 200, a message that carries the gateway identifier and gateway media information of the first gateway occupied by the first MSC-S 100.

The first receiving unit 120 is configured to receive a second gateway identifier that is returned by the second MSC-S 200 to the first MSC-S 100, where the second gateway identifier is the same gateway identifier as the first gateway identifier.

The first receiving unit 120 receives the gateway identifier of the gateway that the other second MSC-S 200 returned by the second MSC-S 200 can use for the call.

The first MSC-S 100 also includes:

The first processing unit 130 is configured to: when the first MSC-S 100 cannot use the second gateway, and the first receiving unit 120 receives the gateway that the other second MSC-S 200 returned by the second MSC-S 200 can use for the call. When the gateway is identified, if the first MSC-S 100 can use other gateways than the second gateway provided by the second MSC-S 200, the gateway is selected as the first gateway.

The first processing unit 130 is further configured to: when the second MSC-S 200 can not use the first gateway to provide services, when the other gateway is selected as the second gateway, the first MSC-S 100 determines the identifier of the second gateway, and then determines Whether the second gateway can be used to provide the service, if the second gateway can be used to provide the service, the occupation of the first gateway is released, and the second gateway is used to establish the bearer according to the gateway media information.

The message mode in which the system and the device carry the gateway identifier includes one or a combination of the following modes:

Use SDP's o= line username or unicast address parameter, i=row, s=row, pass SDP attribute parameter 3=row;

Use the SIP header field;

Use SIP message body;

Adopt ABNF coding method.

In the embodiment of the present invention, multiple MSC-Ss can occupy the same media gateway to optimize the 7-carrier path, avoid multiple SDP interactions, reduce the number of times the MSC-S processes the SDP, implement complexity, and speed up the call setup process. Through the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be implemented by hardware or by means of software plus a necessary general hardware platform. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which may be stored in a non-volatile storage medium (which may be a CD-ROM, a USB flash drive, a mobile hard disk, etc.), including several The instructions are for causing a computer device (which may be a personal computer, server, or network device, etc.) to perform the methods described in various embodiments of the present invention.

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

Claims

Rights request

A method for gateway selection, characterized in that it comprises:

2. The method of gateway selection according to claim 1, further comprising: said second MSC-S returning a second gateway identifier to said first MSC-S, said second gateway identifier and The first gateway identifier is an identifier of the same gateway.

The method of gateway selection according to claim 1, further comprising: when the second MSC-S is not available to provide services by using the first gateway, selecting another gateway as the second gateway, and The first MSC-S returns a message of the gateway identifier and gateway media information of the second gateway.

The method for gateway selection according to claim 1 or 3, further comprising: the second MSC-S receiving the message sent by the first MSC-S, carrying the message outside the first gateway The other first MSC-S can be used for the gateway identifier of the gateway of the call, and when the second MSC-S cannot use the first gateway occupied by the first MSC-S, the other first MSC is used. S can be used for the gateway corresponding to the gateway ID of the call.

The method for gateway selection according to claim 1 or 3, further comprising: the second MSC-S returning to the first MSC-S in addition to the identifier of the second gateway, and returning to the other The identity of the gateway that the second MSC-S can use for the call.

The method for gateway selection according to claim 1 or 3, wherein when the second MSC-S is not available to use the first gateway to provide services, when another gateway is selected as the second gateway,

After receiving the identifier of the second gateway, the first MSC-S determines whether the second gateway can be used to provide services, and if the second gateway is used to provide services, releasing the occupation of the first gateway. And re-using the second gateway to establish a load according to the gateway media information.

7. The method of gateway selection according to claim 5, further comprising: when said first MSC-S is incapable of using said second gateway, and said second MSC-S is directed to said first MSC -S returning the identity of the gateway of the other second MSC-S that can be used for the call, in addition to returning the identity of the second gateway,

If the first MSC-S is able to use other gateways than the second gateway provided by the second MSC-S, the gateway is reselected as the first gateway.

The method for selecting a gateway according to any one of claims 1 to 3, wherein the manner of carrying the message of the gateway identifier comprises at least one of the following manners:

Use the session description protocol SDP o= line username or unicast address parameter, i=row, s=row, pass SDP attribute parameter &= line;

Use the Session Initiation Protocol SIP header field;

Use SIP message body;

The enhanced Bacchus paradigm ABNF coding method is adopted.

9. A gateway selection system, comprising:

a first mobile switching center server MSC-S, configured to send, to the second MSC-S, a message carrying the gateway identifier and gateway media information of the first gateway occupied by the first MSC-S; Receiving, by the first MSC-S, a message carrying the gateway identifier and the gateway media information of the first gateway occupied by the first MSC-S, when the second MSC-S can provide the service by using the first gateway The bearer is established by using the first gateway according to the gateway media information.

10. The gateway selection system of claim 9 wherein:

The second MSC-S is further configured to return the second gateway identifier to the first MSC-S, where the second gateway identifier is an identifier of the same gateway as the first gateway identifier.

11. The gateway selection system of claim 9 wherein:

The second MSC-S is further configured to receive, by the first MSC-S, a gateway identifier of a gateway that is used by the first MSC-S other than the first gateway to be used for the call, when When the second MSC-S cannot use the first gateway occupied by the first MSC-S, the gateway corresponding to the gateway identifier that the other first MSC-S can use for the call is used.

12. The gateway selection system of claim 9 wherein: The second MSC-S is further configured to: when the second MSC-S is not available to provide services by using the first gateway, select another gateway as the second gateway, and return the second to the first MSC-S. The gateway's gateway ID and gateway media information.

The gateway selection system according to claim 9, 11 or 12, wherein the second MSC-S is further configured to return to the first MSC-S that another second MSC-S can be used for The identity of the gateway for this call.

The gateway selection system according to claim 9, 11 or 12, wherein the first MSC-S is further configured to: after receiving the identifier of the second gateway, determine whether the second gateway can be used by the second gateway. The service, if the second gateway is used to provide services, releasing the occupation of the first gateway, and re-using the second gateway to establish a bearer according to the gateway media information; when the first MSC-S cannot use the a second gateway, and if the second MSC-S returns to the first MSC-S, in addition to returning the identity of the second gateway, the gateway identifier of the gateway that the other second MSC-S can use for the call, if The first MSC-S can use the other gateways other than the second gateway provided by the second MSC-S, and then reselect the gateway as the first gateway.

A second mobile switching center server MSC-S, comprising: a second receiving unit, configured to receive a message that is sent by the first MSC-S and carries the gateway identifier of the first gateway and the gateway media information;

16. The second MSC-S of claim 15 wherein:

The second receiving unit is further configured to receive, by using the message sent by the first MSC-S, a gateway identifier of a gateway that the first MSC-S other than the first gateway can use for the call.

The second MSC-S as claimed in claim 15, further comprising: a second sending unit, configured to return the second gateway identifier to the first MSC-S, where the second gateway identifier is The first gateway identifier is an identifier of the same gateway.

18. The second MSC-S of claim 17 wherein:

The second processing unit is further configured to: when the first gateway is not available to provide services When other gateways are selected as the second gateway;

The second sending unit is further configured to: when the second processing unit selects another gateway as the second gateway, returning, to the first MSC-S, the gateway identifier of the second gateway and the gateway media information. Message.

19. The second MSC-S of claim 16 wherein:

The second processing unit is further configured to: when selecting another gateway as the second gateway, preferentially selecting another first MSC-S other than the first gateway sent by the first MSC-S to be used for the current call. The gateway corresponding to the gateway ID.

The second MSC-S according to claim 18 or 19, wherein the second sending unit is further configured to return to the first MSC-S in addition to the identifier of the second gateway. The identity of the gateway that the other second MSC-S can use for the call.

A first mobile switching center server MSC-S, comprising: a first sending unit, configured to send, to a second MSC-S, a gateway identifier that carries the first gateway occupied by the first MSC-S And gateway media information messages.

The first MSC-S according to claim 21, further comprising: a first receiving unit, configured to receive a second gateway identifier returned by the second MSC-S to the first MSC-S The second gateway identifier is an identifier of the same gateway as the first gateway identifier.

23. The first MSC-S of claim 21, wherein:

The first receiving unit is further configured to receive a gateway identifier of a gateway that the second MSC-S returned by the second MSC-S can use for the call;

The first MSC-S further includes:

a first processing unit, configured to: when the first MSC-S cannot use the second gateway, and the first receiving unit receives the other second MSC-S returned by the second MSC-S to be used by the gateway of the call When the gateway is identified, if the first MSC-S can use other gateways than the second gateway provided by the second MSC-S, the gateway is selected as the first gateway.

24. The first MSC-S of claim 23, wherein:

The first processing unit is further configured to: when the second MSC-S cannot use the first gateway to provide a service, and select another gateway as the second gateway, determine whether the The second gateway provides a service. If the second gateway is used to provide services, the occupation of the first gateway is released, and the second gateway is used to establish a bearer according to the gateway media information.