WO2011060694A1

WO2011060694A1 - Method and system for establishing media session

Info

Publication number: WO2011060694A1
Application number: PCT/CN2010/078558
Authority: WO
Inventors: 陈志峰; 郝振武; 胡永生
Original assignee: 中兴通讯股份有限公司
Priority date: 2009-11-20
Filing date: 2010-11-09
Publication date: 2011-05-26
Also published as: CN102075493A

Abstract

A method, system and application server (AS) for establishing a media session are provided in the present invention. The method includes: in the process of establishing the media session between a calling terminal and a called terminal, after receiving a signaling plane message, the Call Session Control Function (CSCF) forwards the signaling plane message to the AS; the AS determines, according to the information of both the calling and called parties and/or the operation configuration, whether to use a media proxy (MP) for transferring; if the AS determines to use the MP for transferring, the AS selects one or more MPs, applies to the selected MP/MPs for media transferring resources, replaces the information of the media resources in the signaling plane message according to the information of the media transferring resources which is applied for, and forwards the replaced signaling plane message via the CSCF. With the present invention, determining, according to the information of both the calling and called parties, whether to use the direct link mode or use the MP-relay link mode for the media plane link established between the calling and called parties is implemented.

Description

Method and system for establishing media session

Technical field

The present invention relates to the field of communications, and in particular, to a method and system for establishing a media session by a terminal of an IP Multimedia Subsystem (IMS). Background technique

IMS is the third Generation Partnership Organization (3 ^rd Generation Partnership Project, referred to as 3GPP) standard defines the next generation network, its distinguishing feature is preclude the use of the Session Initiation Protocol (Session Initiation Protocol, referred to as SIP) system, communication with the ground Incompatibility, IMS can be equipped with multiple media service control functions and bearer separation, call and session separation, application and service separation, service and network separation, and mobile network and Internet service convergence. The trend of communication network convergence development.

The Session Border Controller (SBC) is an access device at the edge of the network defined in the Next Generation Network (NGN). It has: Auxiliary terminal for network address translation (Network Address Translators) , NAT ) traversal, intrusion detection, bandwidth control policies, protection sessions are not stolen, and routing information protocol (RIP) flow congestion and call interference are prevented. The SBC can protect core network equipment from malicious attacks and sudden DOS attacks, prevent other types of security risks such as service spoofing, and provide access control methods to control and guarantee session quality, total number, bandwidth, and type. Based on the above functions of the SBC, although the SBC device is not explicitly defined in the IMS network defined by the 3GPP, when the IMS is actually deployed, the operator usually introduces it into the IMS domain and deploys it on the edge of the IMS network. As an access device of the terminal and an interworking device of other domains.

1 is a schematic structural diagram of an IMS network in which an SBC is deployed in the prior art, and mainly describes network element entities and their associations related to the present invention. The user equipment (User Equipment, UE for short) 101 represents the terminal device used by the user; the Session Border Controllers (SBC) 102 is used as the access device of the IMS core network, and the SBC can be divided into two logical entities: One is called Signaling Gate Controller (SGC). 103. For analyzing and processing signaling messages, performing application layer interworking, controlling media proxy, and performing signaling forwarding, and another called Media Proxy (MP) 104, for media plane data forwarding; Call Session Control Function (CSCF) is the core network element that controls the session process, including: Proxy Call Session Control Function (Proxy-CSCF, P-CSCF for short) 105. Query Call Session Control Function (Interrogating-CSCF) , referred to as I-CSCF (not shown), and service call session control function (Serving-CSCF, S-CSCF for short) 106; Application Server (AS) 107 is a network element that provides value-added multimedia services. .

Since the SBC function has a certain overlap with the P-CSCF in signaling forwarding, the P-CSCF can be used as an option in the IMS network where the SBC is deployed. Therefore, the P-CSCF in Figure 1 is represented by a dashed box. And this aspect is not directly related to the present invention, so in the following flow, the P/I/S-CSCF is collectively referred to as a CSCF for description.

2 is a processing flow of a signaling plane and a media plane in a session establishment of a signaling plane and a media plane through an SBC after the IMS domain is introduced into the SBC device in the prior art, and the specific process description is as follows:

Step 201: Before the UE1 establishes a session with the UE2, the UE1 and the UE2 need to complete the SDP negotiation, and the UE1 sends the SDP providing message to the signaling processing SGC by using the session initiation request message (the session initiation request message is the SIP request message INVITE). The message carries the media face contact address information allocated by the UE1 for the session [SDP: c=A];

Step 202: The SGC allocates a forwarding media plane resource to the calling side of the session on the MP. Step 203: The SGC converts the contact address of the UE1 in the session initiation message to be on the MP.

The UE1 allocates the media plane resource, and the converted contact address is [SDP:c=Tr_A] and sends it to the CSCF. Step 204: The CSCF forwards the session initiation request message to the UE2, in the normal case, between the CSCF and the UE2. There are also SGC and MP devices, and the processing mode is the same as that between the UE1 and the CSCF. For the sake of brevity, the description is omitted, and the impact is ignored. Step 205, UE2 returns a response message (200 OK) The message is sent to the CSCF, and the message carries the media plane contact address information of the UE2 [SDP:c=B];

Step 206, the CSCF forwards the response message (200 OK) to the SGC in the SBC;

Step 207: The SGC allocates a media plane forwarding resource to the UE2 on the MP. Step 208: The SGC uses the media plane forwarding resource [SDP:c=Tr_B] allocated by the MP to replace the media plane contact address information of the UE2 in the original response message (200 OK), and then sends the message to the UE1.

Step 209: UE1 and UE2 complete SDP negotiation, and establish a media link forwarded by the MP allocated by the network between them.

It can be seen that the SGC in the SBC automatically replaces the user information in the message in the normal call process, thereby realizing the information shielding between the terminal and the core network and the terminal and the terminal, improving the security of the network and effectively protecting the session.

The SBC in FIG. 2 is configured to directly allocate media plane forwarding information on the SBC, so that after the message is converted by the SGC in the SBC, one terminal can only obtain the address information allocated by the MP for another terminal through the normal channel, and cannot be known. The original local information of the peer end, so the session connection established between the two terminals can only be transferred through the MP, so that when the existing network conditions can be directly connected, the two terminals must also transit through the MP, resulting in MP resources. And the waste of network resources.

Therefore, in the prior art, the SBC also provides a multimedia session establishment process called a Hairpin mode. Before the Hairpin mode session, the SGC is configured in the Hairpin mode, the SGC does not automatically allocate media resources for the session. The two parties directly establish a media link to conduct a session. The process is shown in Figure 3. The specific process description is as follows:

Step 301: UE1 sends a session initiation request message (INVITE) to the signaling processing unit SGC by using the SIP protocol, where the message carries the media plane contact address information allocated by the UE1 for the session [SDP: c=A];

Step 302, the SGC executes Hairpin, does not apply to the MP for media side forwarding resources, and sends a SIP request message carrying the media plane contact address information [SDP:c=A] to the CSCF;

Step 303, the CSCF forwards the SIP request message to the UE2.

Step 304: The UE2 returns a response message (200 OK) to the CSCF, where the message carries the media plane contact address information of the UE2 [SDP:c=B];

Step 305, the CSCF forwards the response message (200 OK) to the SGC;

Step 306, the SGC sends a response message (200 OK) to the UE1; In step 307, UE1 and UE2 complete the SDP negotiation, and establish a direct media link between them.

However, when the Hairpin mode is enabled on the SBC, the calling party and the called party establish a directly connected media link. Since the SBC is located at the edge of the network, when the call is initiated, the SBC located on the calling side can only know the access information of the calling terminal. Without knowing the access information of the called side device, it is only possible to decide whether to adopt the Hairpin according to the pre-configuration or the calling information, so that the calling party and the called party can establish a media link or a direct link through the MP relay. In the current network environment, it is often necessary to decide whether to use the MP relay according to the information of the calling party and the called party. When a terminal is used as the calling party, the MP media transfer plane needs to be used when calling the user, and the calling user B does not. Need; even if you call the same user under different conditions, there will be a situation where you need an MP relay media face, but not next time. At this time, it is necessary to judge whether the network element in the media plane needs to know the information of the calling party and the called party at the same time. Obviously, the SBC located at the edge of the network does not have such capability, and therefore a new method of establishing a media session needs to be sought. Summary of the invention

The technical problem to be solved by the present invention is to provide a method and system for establishing a media session, which overcomes the prior art that the direct link or the link through the MP relay can only be determined according to the access information or pre-configuration of the calling terminal. The flaw of the way.

In order to solve the above technical problem, the present invention provides a method for establishing a media session, including: in a process of establishing a media session between a calling terminal and a called terminal, after the call session control function (CSCF) receives the signaling plane message, Forwarding the signaling plane message to an application server (AS); the AS determines whether to use media agent (MP) relay according to information of the calling party and the called party and/or an operational configuration;

If the MP transit is determined, the AS selects one or more MPs, applies the media transfer resource to the selected MP, and replaces the media resource information in the signaling plane message according to the applied media relay resource information. The CSCF forwards the replaced signaling plane message.

The above method can also have the following characteristics:

The AS selects the MP based on the information and/or operational configuration of both the calling and called parties.

The above method can also have the following characteristics: The information of the calling party and the called party includes: a preference of the calling user and the called user, a specific location of the calling terminal and the called terminal, and a session border controller on the calling terminal side and the called terminal side.

(SBC) location;

The operation configuration refers to: an operator operation strategy.

The above method can also have the following characteristics:

Before the AS determines whether to adopt the MP transit, the method further includes: the AS collecting information about the specific location of the calling terminal and the called terminal;

The preferences of the calling user and the called user, the SBC location of the calling terminal side and the called terminal side, and the operator operation policy are pre-set information.

The above method can also have the following characteristics:

The step of the AS collecting the specific locations of the calling terminal and the called terminal includes:

When the terminal is registered, the device carries the location information and triggers the third-party registration to the AS to complete the information collection. Alternatively, the underlying IP router reports the location information to the AS. Alternatively, the terminal uses the application layer protocol to report the location information to the AS.

The above method can also have the following characteristics:

The signaling plane message refers to: a session initiation request message or a session initiation response message.

In order to solve the above technical problem, the present invention provides a system for establishing a media session, including a calling terminal, a called terminal, a CSCF, and an AS;

The CSCF is configured to: forward a signaling plane message to the AS during a media session between the calling terminal and the called terminal;

The AS is configured to: determine whether to adopt MP relay according to information and/or operation configuration of both the calling party and the called party; if it is decided to adopt MP relay, the AS selects one or more MPs, and applies for media to the selected MP. Transmitting the resource, and replacing the media resource information in the signaling plane message according to the applied media relay resource information, and forwarding the replaced signaling plane message by using the CSCF.

The above system can also have the following characteristics:

The AS is further configured to: select an MP based on information and/or operational configuration of both the calling and called parties. The above system can also have the following characteristics: The information of the calling party and the called party includes: a preference of the calling user and the called user, a specific location of the calling terminal and the called terminal, and an SBC location of the calling terminal side and the called terminal side;

The operation configuration refers to: an operator operation strategy.

The above system can also have the following characteristics:

The AS is further configured to: collect information about specific locations of the calling terminal and the called terminal; preferences of the calling user and the called user, SBC location of the calling terminal side and the called terminal side, and an operator. The operational strategy is pre-set information.

An application server (AS) for establishing a media session, the AS is configured to: determine whether to use a media agent (MP) relay according to information and/or operational configuration of both the calling and called parties; if it is decided to use MP relay, Selecting one or more MPs, forwarding the resources to the selected MP, and replacing the media resource information in the signaling plane message according to the applied media relay resource information, and forwarding the call through the call session control function (CSCF) The replaced signaling plane message.

The AS is further configured to: select an MP based on information and/or operational configuration of both the calling and called parties. The information of the calling party and the called party includes: a preference of the calling user and the called user, a specific location of the calling terminal and the called terminal, and an SBC location of the calling terminal side and the called terminal side;

The operation configuration refers to: an operator operation strategy.

According to the present invention, it is possible to determine whether the media plane link established between the calling party and the called party is a direct link or a link mode by MP relay according to the information of both the calling party and the called party. BRIEF abstract

1 is a schematic diagram of a network architecture in the prior art;

2 is a schematic diagram of a session establishment process in the prior art;

3 is a schematic diagram of a session establishment process in a Hairpin mode in the prior art; 4 is a schematic diagram of a network architecture according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a flow of using MP transfer in the application example 1 of the present invention; FIG.

FIG. 6 is a schematic flowchart of a terminal directly establishing a session according to an application example 2 of the present invention. Preferred embodiment of the invention

In the present invention, the application server (AS) determines whether to use the MP relay according to the information and/or the operation configuration of both the calling party and the called party, and the AS applies for the media transfer resource to the selected MP.

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

As shown in FIG. 4, in the embodiment of the present invention, an AS is used to control one or more networks.

Media gateway device in the SBC. The AS is connected to the MP, and the AS controls the MP to perform operations such as allocation, release, and update of media resources.

The method of the embodiment of the invention includes:

In the process of establishing a media session between the calling terminal and the called terminal, the CSCF forwards the signaling plane message to the AS after receiving the signaling plane message;

The AS determines whether to use the MP relay according to the information of the calling and called parties and/or the operational configuration;

If the MP transit is decided, the AS selects one or more MPs for the media session, applies the media transfer resource to the selected MP for the media session, and replaces the signaling according to the applied media relay resource information. The media resource information in the face message, and the signaling plane message is further forwarded by the CSCF.

The signaling plane message specifically refers to: a session initiation request message or a session initiation response message.

When the signaling plane message passes through the SGC network element, the SGC no longer applies for the media relay resource for the media session.

Preferably, when the AS selects the MP, the AS selects according to the information of the calling party and the called party, the Z or the operation configuration, and the like. The AS determines the MP behavior based on the information of the calling and called parties. In the operational configuration, the information of the calling party and the called party includes: the preferences of the calling user and the called user, the calling terminal and the called terminal. The specific location, and the SBC location on the calling terminal side and the called terminal side, etc.; the operation configuration includes: an operator operation policy.

The specific location of the calling terminal and the called terminal is information collected by the AS; the preferences of the calling user and the called user, the SBC location of the calling terminal side and the called terminal side, and the operator. The operational strategy is pre-set information.

The manner in which the AS collects specific locations of the calling terminal and the called terminal may include:

The terminal carries the location information and triggers the third-party registration to the AS to complete the information collection. Alternatively, the underlying IP router reports the location information to the AS. Alternatively, the terminal reports the location information to the AS by using the application layer protocol.

If the AS decides not to use the MP relay, the signaling plane message is not modified, and the signaling plane message is directly returned to the CSCF, and the signaling plane message is further forwarded by the CSCF.

The replacement of the media resource information in the signaling plane message by the AS according to the media relay resource information of the application refers to: the AS replaces the media plane contact address information of the calling terminal or the called terminal with the transit address information.

The system for establishing a media session in the embodiment of the present invention includes a calling terminal, a called terminal, a CSCF, and an AS.

The CSCF is used to forward the received signaling plane message to the AS during the establishment of the media session between the calling terminal and the called terminal;

The AS is configured to determine whether to use MP relay according to information and/or operational configuration of both the calling party and the called party; if it is decided to use MP relay, the AS selects one or more MPs, and applies for media to the selected MP. Transmitting the resource, and replacing the media resource information in the signaling plane message according to the applied media relay resource information, and further forwarding the signaling plane message by using the CSCF.

The AS is further configured to select an MP based on information and/or operational configurations of both the calling and called parties. The following is further illustrated by the application examples of the present invention.

Application example one As shown in FIG. 5, the flowchart of the application example 1 of the present invention includes the following steps: Step 501: The UE1 sends a session initiation request message (the session initiation request message is a SIP request message INVITE) to the SGC device, where the message is carried. UE1 media face contact address information assigned to this session [SDP:c=A];

Step 502: The SGC device does not apply for the media plane resource reservation at this time, and does not modify the media plane contact address information, and forwards the SIP request message to the CSCF. The media plane contact address information of the UE1 carried in the message is still [SDP:c =A];

Step 503, the CSCF forwards the request message to the AS;

Step 504: The AS determines, according to the location information of the calling party and the called party, the preference settings of the calling party and the called party, the location information of the SBC in the network, and the operation policy, whether the call requires the MP to perform media plane relay, in this example process. It is determined that the transfer needs to be performed, so the MP is selected for the session; Step 505, the AS applies the media face transfer resource to the selected MP for the session, and allocates resources for the media face contact address of the UE1;

The selected MP may be that the SGC in step 502 belongs to the same SBC, or may be a different SBC than the SGC;

Step 506: After the MP completes the resource allocation, the MP returns the allocation result to the AS, and the assigned media plane contact address is [c=Tr_A];

Step 507, the AS replaces the media plane contact address information of the UE1 in the SIP request message with the transit address information, and the media plane address is [SDP:c=Tr_A], and is sent to the CSCF;

Step 508, the CSCF forwards the request message to the peer terminal UE2, and the SDP information included in the message is [SDP:c=Tr_A];

Here, there may also be an SBC between CSCF and UE2, and the reservation process is similar to that of the calling side. Here, for clarity and training, it is omitted;

Step 509: The UE2 returns a session initiation response message (200 OK) to the CSCF, where the message carries the media plane contact address information of the UE ² [SDP:c=B];

Step 510, the CSCF forwards the response message (200 OK) to the AS;

Step 511: The AS controls the MP to perform resource reservation by using a SIP message, and is a media interface of the UE2. Department address allocation resources;

Step 512: After the MP completes resource allocation, the MP returns the allocation result to the AS, and the assigned media plane contact address is [c=Tr_B];

Step 513, the AS replaces the media plane contact address information of the UE2 in the response message (200 OK) with [SDP:c=Tr_B], and sends the message to the CSCF.

Step 514, the CSCF forwards the response message (200 OK) to the SGC;

Step 515, the SGC no longer modifies the media face contact address information in the response message (200 OK), and forwards the message to UE1;

Step 516, UE1 and UE2 complete the SDP negotiation, and establish a media link forwarded by the MP between them.

Application example two

In the application example depicted in Figure 5, a media plane link forwarded by the MP is established between the calling parties. The invention can also directly contact the media face between the calling and the called party. The flow is shown in Figure 6. The specific process is as follows:

Step 601: The UE1 sends a session initiation request message to the SGC device, where the UE1 carried in the message is the media plane contact address information allocated for the session [SDP:c=A];

Step 602: The SGC device does not apply for the media plane resource reservation at this time, and does not modify the media plane contact address information, and forwards the request message to the CSCF. The media plane contact address information of the UE1 carried in the message is still [SDP:c =A];

Step 603, the CSCF forwards the request message to the AS;

Step 604: The AS determines, according to the location information of the calling party and the called party, the preference settings of the calling party and the called party, the location information of the SBC in the network, and the operation policy, whether the call requires the MP to perform media plane relay, in this example process. Judging that no transfer is required;

Step 605: Therefore, the AS does not modify the media plane contact address in the SDP message, and forwards the request message to the CSCF, and the media plane address information carried in the message is still [SDP:c=A]; Step 606, the CSCF forwards the request message. To the peer terminal UE2; Step 607: The UE2 returns a session initiation response message (200 OK) to the CSCF, where the message carries the media plane contact address information of the UE2 [SDP:c=B];

Step 608, the CSCF forwards the response message (200 OK) to the AS;

Step 609: The AS directly forwards the message to the CSCF because the MP does not need to forward the session.

Step 610, the CSCF forwards the response message (200 OK) to the SGC;

Step 611, the SGC no longer modifies the media face contact address information in the response message (200 OK), and forwards the message to UE1;

Step 612, UE1 and UE2 complete the SDP negotiation, and establish a direct connection media link between them.

Since the AS-like deployment is located at the center of the IMS network, and the SBC is located at the edge of the IMS network, when the IMS network has a certain time, the distance between the AS and the SBC is quite far, and each communication between them is It takes a lot of resources and a long time, so saving a reservation process here is still quite practical.

It can be seen that through the present invention, it is possible to determine whether the media side link established between the calling party and the called party is a direct link or a link mode via MP relay, based on the information of both the calling party and the called party.

The invention may, of course, be embodied in a variety of other embodiments without departing from the spirit and scope of the invention. Changes and modifications are intended to be included within the scope of the appended claims.

Industrial applicability

The invention can realize whether the media side link established between the calling party and the called party is a direct link or a link mode through the MP relay according to the information of the calling party and the called party.

Claims

Claim

1. A method of establishing a media session, comprising:

Call session control function in the process of establishing a media session between the calling terminal and the called terminal

(CSCF) after receiving the signaling plane message, forwarding the signaling plane message to an application server (AS);

The AS determines whether to use media agent (MP) relay according to the information of the calling and called parties and/or the operational configuration;

2. The method of claim 1 wherein

3. The method according to claim 1 or 2, wherein

The information of the calling party and the called party includes: a preference of the calling user and the called user, a specific location of the calling terminal and the called terminal, and a session border controller of the calling terminal side and the called terminal side (SBC) Location

The operation configuration refers to: an operator operation strategy.

4. The method of claim 3, wherein

Before the AS determines whether to use the MP transit, the method further includes: the AS collecting information about the specific location of the calling terminal and the called terminal;

5. The method of claim 4, wherein

Carrying the location information when the terminal is registered, and triggering the third-party registration to the AS to complete the information collection; or, the underlying IP router reports the location information to the AS; or, the terminal adopts the application layer protocol. Report location information to the AS.

6. The method of claim 1, wherein

7. A system for establishing a media session, comprising a calling terminal, a called terminal, a call session control function (CSCF), and an application server (AS);

The AS is configured to: determine whether to use media agent (MP) relay according to information and/or operational configuration of both the calling party and the called party; if it decides to use MP relay, the AS selects one or more MPs, and selects The specified MP applies for media transfer resources, and replaces the media resource information in the signaling plane message according to the applied media relay resource information, and forwards the replaced signaling plane message by using the CSCF.

8. The system of claim 7, wherein

The AS is further configured to: select an MP based on information and/or operational configuration of both the calling and called parties.

9. The system of claim 7 or 8, wherein

The information of the calling party and the called party includes: a preference of the calling user and the called user, a specific location of the calling terminal and the called terminal, and an SBC location of the calling terminal side and the called terminal side;

The operation configuration refers to: an operator operation strategy.

10. The system of claim 9, wherein

11. An application server (AS) for establishing a media session, wherein the AS is configured to: determine whether to use a media agent (MP) relay according to information and/or operational configuration of both the calling party and the called party; if it is decided to adopt MP relay, Then select one or more MPs to transfer funds to the selected MP application media. Source, and replacing the media resource information in the signaling plane message according to the applied media relay resource information, and forwarding the replaced signaling plane message by using a call session control function (CSCF).

12. The AS according to claim 11, wherein the AS is further configured to: select an MP according to information and/or an operational configuration of both the calling party and the called party.

13. The AS according to claim 12, wherein the information of the calling party and the called party includes: a preference of the calling user and the called user, a specific location of the calling terminal and the called terminal, and a calling terminal. Side and side SBC positions on the called terminal side;

The operation configuration refers to: an operator operation strategy.

The AS according to claim 13, wherein the AS is further configured to: collect information about specific locations of the calling terminal and the called terminal;