KR100710253B1 - method for processing session initiation protocol, and system for providing internet protocol multimedia service based on the same - Google Patents

Abstract

The present invention relates to a method for processing a Session Initiation Protocol (SIP) in communication, particularly in an Internet Protocol Multimedia Subsystem (IMS) of third generation asynchronous mobile communications, and to a system for providing Internet Protocol (IP) multimedia services based thereon. A method and system for supporting session initiation protocol (SIP) registration and signaling compression (SigComp) for more efficient session initiation protocol (SIP) call processing in an Internet protocol multimedia subsystem (IMS) of third generation asynchronous mobile communication. The present invention also provides improved session initiation protocol (SIP) registration and signaling compression (SigComp) of a user equipment (UE) to be suitable for a session initiation protocol (SIP) based Internet protocol (IP) multimedia service.

Signaling Compression (SigComp), Session Initiation Protocol (SIP), Internet Protocol Multimedia Subsystem (IMS), Proxy-Call Session Control Function (P-CSCF)

Description

Method for processing session initiation protocol, and system for providing internet protocol multimedia service based on the same

1 illustrates a network configuration of a conventional Internet Protocol Multimedia Subsystem (IMS).

2 is a diagram illustrating a procedure for finding a conventional proxy-call session control function (P-CSCF).

3 illustrates a configuration and procedure for signaling compression (SigComp) processing used in Session Initiation Protocol (SIP) registration in accordance with the present invention.

4 illustrates a configuration and procedure for Session Initiation Protocol (SIP) registration in accordance with the present invention.

TECHNICAL FIELD The present invention relates to communications, and in particular, a method for processing a Session Initiation Protocol (SIP) in an Internet Protocol Multimedia Subsystem (IMS) of a third generation asynchronous mobile communication, and a system for providing an Internet Protocol (IP) multimedia service based thereon. It is about.

1 is a diagram illustrating a network configuration of a conventional Internet Protocol Multimedia Subsystem (IMS), and is an IP multimedia subsystem (IP) for an Internet Protocol (IP) multimedia service in a third generation asynchronous mobile communication. Multimedia Subsystem (hereinafter, abbreviated as IMS).

Referring to FIG. 1, the conventional IMS is a Call Session Control Function (hereinafter referred to as Call Session Control Function) that is in charge of a part related to call and session processing of the Session Initiation Protocol (hereinafter referred to as SIP). Abbreviated as CSCF), Media Gateway Control Function (MGCF) to handle protocol conversion between SIP and ISDN User Part (PSTN), and Public Switched Telephony Network (PSTN). ) To convert the MIDI data (eg, real-time transport protocol (RTP) data) in the form of IP packets in the IMS into a form that can be transmitted on a bearer of a circuit switched network for interworking with a previous generation (2nd generation / 2.5th generation) network. IMS-Media Gateway (MGW) is responsible for selecting the destination network through the translation of the number of the public telephone network (PSTN) for the incoming call from the IMS to the public telephone network (PSTN). Breakout Gateway Control Function (BGCF), Signaling Gateway (SGW) for converting the transport layer of the signaling protocol, and Home Subscriber Server (HSS) serving as a database for the user. : Home Subscriber Server).

The above-described CSCF may be a proxy-call session control function (Proxy-CSCF; P-CSCF), an interrogating-call session control function (I-CSCF), a serving-call session according to a function. It is divided into three types of control functions (Serving-CSCF; hereinafter referred to as S-CSCF).

The P-CSCF is the first point where a user equipment (hereinafter referred to as UE) connects to an IMS and requests or responds to a SIP message from the UE.

The I-CSCF is the first point of access to the home network of the UE, and routes SIP messages received from other networks to the S-CSCF.

The S-CSCF performs control services while managing session state of an actual registered UE.

In the conventional IMS having the above-described configuration, call processing is performed using SIP for IP multimedia service. In addition, traffic processing is performed using a real-time transfer protocol (RTP).

On the other hand, in the 3rd generation asynchronous mobile communication network, in order for a UE to execute a SIP-based IP multimedia application, SIP registration must be completed in IMS.

Meanwhile, for SIP registration, the UE must first find the P-CSCF of FIG. 2.

2 is a diagram illustrating a conventional procedure for finding a P-CSCF.

Referring to FIG. 2, in order to find a P-CSCF, a UE first accesses a General Packet Radio Service (hereinafter, referred to as GPRS) network (GPRS attach) (S1). That is, the UE registers its location in the GPRS network.

Subsequently, a packet data protocol (PDP) context activation procedure (SDP) requesting an IP multimedia service is required, which is performed by the UE with a Serving GPRS Support Node (SGSN). Accordingly, the system side recognizes that the UE is roaming in its service area. The UE then starts SIP registration with the IMS. In other words, for SIP registration, the UE first searches for a P-CSCF.

At this time, the domain name of the P-CSCF and the IP address of the Domain Name Service (DNS) server are obtained using the Dynamic Host Configuration Protocol (DHCP) (S3). Next, the P-CSCF address is obtained from the DNS server (S4). Thus the UE completes registration with the P-CSCF.

Meanwhile, as the 3G mobile communication network has evolved into an IP network, a structure of processing a call based on SIP in an IMS domain for an IP multimedia service has been introduced. In particular, a message compression scheme is used to increase transmission efficiency when sending and receiving SIP messages for SIP registration, which is called Signaling Compression (SigComp).

SIP, a protocol used for call processing in IMS, is a text-based protocol. Therefore, the SIP message is compressed and transmitted for use in a mobile communication network constrained by radio resources. At this time, use SigComp.

However, if the UE that supports SigComp transmits the SIP message to the server side but the server side does not support SigComp, the server side cannot parse the SIP message. Therefore, the server side cannot send a response message to the SIP message.

Meanwhile, the UE compresses and transmits a SIP message to SigComp and starts a timer. And if there is no response message from the server side for a predetermined time (until timer expiration) after the UE transmits the SIP message, the UE does not compress the SIP message previously compressed and transmitted. And try to resend.

In reality, even though the server side supports SigComp, the server side may not send a response message to the UE due to other reasons such as network instability or traffic overload. In this case, it is preferable that the UE compresses and transmits the SIP message again.

However, the UE does not recognize network instability or traffic overload, and it is mistaken that the server side does not support SigComp. Therefore, the UE retransmits the SIP message without compressing it.

As a result, unnecessary message retransmission occurs in the related art, and there is a problem of increasing traffic load by not compressing a transmitted message even though SigComp is supported.

An object of the present invention has been made in view of the above, the SIP processing method for supporting SIP registration and SigComp for more efficient SIP call processing in IMS of 3rd generation asynchronous mobile communication, and based on the IP multimedia service To provide a system to

Another object of the present invention is to provide a SIP processing method for improving SIP registration and SigComp of a UE so as to be suitable for a SIP-based IP multimedia service, and a system for providing an IP multimedia service based thereon.

According to an aspect of the present invention, there is provided a method of processing a session initiation protocol in a mobile communication network that receives a multimedia service request from a location registered user equipment (UE), wherein the mobile communication network is connected to the UE. Performing an authentication for the UE, as the UE is authenticated, the mobile communication network searching for an address value of a system that will provide the multimedia service to the UE, and the mobile communication network transmitting the found address value to the UE. Providing, by the system, receiving a SIP message compressed by SigComp from the UE for registration with a system corresponding to the address value of the UE, and indicating whether the system supports the SigComp And sending a status message to the UE.

Preferably, the mobile communication network is asynchronous.

Preferably, the mobile communication network is a GPRS network.

Advantageously, said multimedia service is an IP multimedia service based on said SIP.

Preferably, the gateway GPRS support node (GGSN) of the mobile communication network retrieves the address value of the system from the address table provided in advance and provides it to the UE.

Preferably, the system for providing the multimedia service is IMS. In particular, the address value is an address value of the P-CSCF of the IMS.

Another aspect of the present invention for achieving the above object is a method for processing a session initiation protocol in a UE receiving a multimedia service from a mobile communication network, the address value of a system for providing the multimedia service from the mobile communication network Receiving a message, compressing a SIP message for registration of a SIP to the system by SigComp, transmitting the compressed message to the system, a status message indicating whether the system supports the SigComp from the system Receiving, and retransmitting the transmitted SIP message with reference to the status message.
Preferably, when transmitting the compressed message, a timer provided in advance is started. Accordingly, prior to expiration of the timer, upon receiving the status message from the system in which the information indicating that the SigComp is not inserted is received, the transmitted SIP message is retransmitted without compression. However, as the status message is not received from the system until expiration of the timer, the transmitted SIP message is compressed and retransmitted.

Another feature of the present invention for achieving the above object is a user equipment (UE) for requesting an IP multimedia service based on SIP, an Internet Protocol Multimedia Subsystem (IMS) for providing the multimedia service to the UE, and the And a mobile communication network for providing an address value of the IMS to a UE, wherein the UE compresses a SIP message for SIP registration with the IMS by SigComp and transmits the SIP message to the IMS. A status message indicating whether or not support is transmitted to the UE, and then the UE retransmits the SIP message with reference to the status message.

Preferably, the mobile communication network is a GPRS network.
Preferably, the mobile communication network is provided with a gateway GPRS support node (GGSN) of a GPRS network, wherein the GPS support node (GGSN) comprises an address table including address values of the IMS. Have

Preferably, the UE uses the address value provided in the mobile communication network when registering the SIP with the IMS.
Preferably, if the status message is not received from the IMS within a predetermined time, the UE compresses and retransmits the SIP message.
Preferably, when the information that the IMS does not support the SigComp is inserted into the status message, the UE retransmits the SIP message without compressing.

Preferably, the address value is an address value of the P-CSCF of the IMS.

Other objects, features and advantages of the present invention will become apparent from the detailed description of the embodiments with reference to the accompanying drawings.

Hereinafter, with reference to the accompanying drawings illustrating the configuration and operation of the embodiment of the present invention, the configuration and operation of the present invention shown in the drawings and described by it will be described by at least one embodiment, By the technical spirit of the present invention described above and its core configuration and operation is not limited.

The present invention provides the configuration and procedure of FIG. 4 to find an IMS faster for SIP registration, and sends SIP messages using SigComp to achieve better performance in the SIP registration process. In particular, in the present invention, as shown in FIG. 3, a UE transmits a SIP message using SigComp and improves an error that may occur when a server side (IMS) that does not support SigComp receives the SIP message.

On the other hand, in order to use the SIP-based IP multimedia service, the UE needs to register SIP with IMS. Here for SIP registration, the UE must find the IMS (especially P-CSCF, which is the first point of access to the IMS). The present invention allows for faster finding of P-CSCF.

The present invention is to provide a faster access to the IMS when the UE belonging to the mobile communication network to use the IP-based multimedia service. To this end, the mobile communication network is provided with a table of address values used to access the IMS in advance, and when a UE requests the IP-based multimedia service after registering a location, a predetermined address value is immediately provided to the UE from the provided table. do. As a result, the present invention provides an address value to be used by the mobile communication network to access the IMS to the UE without interworking with a separate external server.

Meanwhile, when the UE transmits a SIP message using SigComp in the process of registering a SIP with the IMS using the address value provided by the mobile communication network, the present invention is implemented as shown in FIG. 3. Here, before or after, the mobile communication network is described as GPRS, but is not limited thereto.

3 is a diagram illustrating a configuration and procedure for SigComp processing used in SIP registration according to the present invention.

Referring to FIG. 3, the UE supporting SigComp compresses the SIP message and transmits the SIP message to the server (S10). Simultaneously with the SIP message transmission, the UE starts a timer. In the above, the server side is an IMS core, more specifically, a P-CSCF.

However, the UE supporting SigComp transmits the SIP message to the server side, but the server side does not support SigComp, so the server side cannot parse the received SIP message.

 Accordingly, the server side transmits a status message (Status) indicating whether to support SigComp to the UE (S11). SigComp support disabled (cause = notsupport) in the cause field (Cause) of the status message includes an error reason. That is, the server side inserts error reason information (SigComp not supported) in the cause field (Cause) of the status message (Status) to inform the UE that parsing of the currently received SIP message is not performed.

Upon receiving the status message (Status), the UE resets the running timer and retransmits the SIP message to the server side without compressing the SIP message (S12).

In the present invention, since the process as shown in FIG. 3 described above, if the timer started after the UE has not received a status message (Status) from the server side after compressing and transmitting the SIP message with SigComp, It supports SigComp and recognizes that the server side did not send a response message just because of other reasons such as network instability or traffic overload.

After all, in the present invention, if the timer started without receiving a status message (Status) from the server after the UE compresses and transmits the SIP message as described above, the UE expires the SIP message compressed with SigComp. Resend the server to the server side.

As described above, in the present invention, by providing a status message (Status) necessary for transmitting and receiving a SIP message from the server side to the UE, the UE can accurately recognize information for transmitting the SIP message with reference to the status message (Status). Accordingly, the UE determines whether to retransmit the previously transmitted SIP message based on the status message.

4 is a diagram illustrating a configuration and procedure for SIP registration according to the present invention.

4, in the asynchronous mobile communication network according to the present invention, in order for a UE to use a SIP-based IP multimedia service, a UE must register SIP with an IMS through its mobile communication network.

On the other hand, in order for the UE to register SIP with the IMS, the UE must first find the IMS. In particular, you need to find the P-CSCF, the first point of contact with the IMS. 4 shows a procedure for finding a P-CSCF and completing SIP registration thereafter.

To find a P-CSCF, the UE must obtain the address value of that P-CSCF. In the present invention, the address value of the P-CSCF is not obtained through a DHCP server or a DNS server.

In the present invention, the gateway GPRS support node (GGSN) of the GPRS network, which is a mobile communication network to which the UE belongs, includes an address table of the P-CSCF. Accordingly, the operation of the configurations for SIP registration of Figure 4 and a series of procedures will be described in more detail.

In order to find the P-CSCF, the UE first attaches to the GPRS network (GPRS attach) (S20). In this case, the UE accesses the GPRS network by registering the location with the GPRS network. After the location registration to the mobile communication network, the UE requests a service from the GPRS network to use a specific service.

Subsequently, the UE requests activation of a packet data protocol (PDP) context to a serving GPRS support node (SGSN) of a GPRS network in order to use an IP-based multimedia service (S21).

Accordingly, the serving GPRS support node (SGSN) requests the gateway GPRS support node (GGSN) to generate a packet data protocol (PDP) context (S22).

The gateway GPRS support node (GGSN) then retrieves the address table of the equipped P-CSCF (S23) and responds to the serving GPRS support node (SGSN) to the packet data protocol (PDP) context creation request (S24). ). At this time, the gateway GPRS support node (GGSN) forwards the P-CSCF address value to be routed to the IMS to the serving GPRS support node (SGSN) using the response message.

In addition, the serving GPRS support node (SGSN) allows the UE to activate a packet data protocol (PDP) context (S25). That is, the authorization message is used to transmit the P-CSCF address value to be routed to the IMS to the UE.

Meanwhile, the Serving GPRS Support Node (SGSN) and the Gateway GPRS Support Node (GGSN) are components belonging to a GPRS network, and the GPRS network checks whether the UE is an IMS service user. In other words, service authentication is performed for the UE. In this case, refer to the IMS service use flag setting value of the UE. The flag setting value is determined by the gateway GPRS support node (S21) requesting activation of the above-described packet data protocol (PDP) context (S21) and requesting generation of a packet data protocol (PDP) context (S22). GGSN).

If the UE is an IMS service user, the UE immediately informs the UE of the P-CSCF address value retrieved from the P-CSCF address table of the gateway GPRS support node (GGSN). This is informed using a packet data protocol (PDP) context creation response message and a packet data protocol (PDP) context activation permission message.

As described above, as the UE acquires an IMS address value (particularly, a P-CSCF address value) from the GPRS network, the UE immediately performs SIP registration with the IMS using the obtained P-CSCF address value (S26). . 3 is an improved scheme of using SigComp in the SIP registration process.

In summary, the UE needs to register SIP in the IMS in order to use the SIP-based IP multimedia service. At this time, for SIP registration, it is necessary to find P-CSCF, the first point of accessing IMS. 4 is a configuration and procedure of the present invention for finding P-CSCF faster. Finding an IMS (especially P-CSCF) through the UE in FIG. 4 is equivalent to registering with IMS (P-CSCF). This IMS registration is realized by sending a SIP message to the server side (IMS) in the same manner as in FIG.

The present invention allows the P-CSCF to be found more quickly, thereby improving the overall call processing performance of SIP as well as SIP registration.

In addition, efficient SIP signaling is possible by using the improved SIP processing scheme of the present invention. This enables better quality of service.

In addition, in SIP call processing for providing an IP-based multimedia service in a 3GPP mobile communication network, which is a third generation asynchronous, the present invention can improve the transmission efficiency by improving the compression transmission method of the text-based SIP and improve the SIP registration procedure. Its simple structure allows for fast call processing.

As a result, according to the present invention, it is possible to provide a high quality IP based multimedia service in a mobile communication network.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (18)

Claims [1] A method for processing a session initiation protocol in a mobile communication network receiving a multimedia service request from a location registered user equipment. The mobile communication network authenticating the user device; When the user device is authenticated, the mobile communication network retrieving an address value of a system to provide the multimedia service to the user device; Providing, by the mobile communication network, the retrieved address value to the user device; Receiving, from the user device, a session initiation protocol message compressed by signaling compression for registration with a system corresponding to the address value of the user device; And And transmitting, by the system, a status message indicating whether the signaling compression is supported to the user device. The method of claim 1, wherein the mobile communication network is asynchronous. The method of claim 1, wherein the mobile communication network is a General Packet Radio Service (GPRS) network. The method of claim 1, wherein the multimedia service is an Internet Protocol multimedia service based on the session initiation protocol. The method of claim 1, wherein the gateway GPRS support node (GGSN) of the mobile communication network retrieves an address value of the system from a pre-addressed address table and provides the same to the user device. How to Initiate Session Initiation Protocol. 2. The method of claim 1 wherein the system is an Internet Protocol Multimedia Subsystem. 7. The method of claim 6 wherein the address value is an address value of a proxy-call session control function of the internet protocol multimedia subsystem. A method for processing a session initiation protocol in a user device provided with a multimedia service from a mobile communication network, Receiving an address value of a system for providing the multimedia service from the mobile communication network; Compressing, by signaling compression, a session initiation protocol message for session initiation protocol registration with the system; Sending the compressed message to the system; Receiving a status message from the system indicating whether the system supports the signaling compression; And And retransmitting the transmitted session initiation protocol message with reference to the status message. 10. The method of claim 8, wherein a timer provided in advance is started when the compressed message is transmitted. 10. The method according to claim 9, wherein before the expiration of the timer, the state message including the information indicating that the signaling compression is not inserted is received from the system, and thus the transmitted session initiation protocol message is retransmitted without compression. Session initiation protocol processing method. 10. The method of claim 9, wherein as the status message is not received from the system until expiration of the timer, the transmitted session initiation protocol message is compressed and retransmitted. A user equipment for requesting an Internet Protocol multimedia service based on a session initiation protocol; An Internet Protocol Multimedia Subsystem for providing the multimedia service to the user device; And A mobile communication network providing an address value of the internet protocol multimedia subsystem to the user device, The user equipment compresses, by signaling compression, a session initiation protocol message for session initiation protocol registration with the internet protocol multimedia subsystem to the internet protocol multimedia subsystem, whereby the internet protocol multimedia subsystem causes the signaling. And a status message indicating whether compression is supported to the user device, and then the user device retransmits the session initiation protocol message with reference to the status message. The system of claim 12, wherein the mobile communication network is a General Packet Radio Service (GPRS) network. 13. The mobile communication network of claim 12, wherein the mobile communication network is provided with a gateway GPRS support node (GGSN) of a GPS network, wherein the GPS protocol node (GGSN) is connected to the Internet protocol multimedia subsystem. A system for providing an internet protocol multimedia service, characterized in that it has an address table containing address values. 13. The system of claim 12, wherein the user device uses the address value provided in the mobile communication network when registering a session initiation protocol with the internet protocol multimedia subsystem. . 13. The method of claim 12, wherein if the status message is not received from the Internet protocol multimedia subsystem within a predetermined time, the user equipment compresses and retransmits the session initiation protocol message. system. 13. The Internet of claim 12, wherein the user device retransmits the session initiation protocol message without compression if information is inserted in the status message indicating that the internet protocol multimedia subsystem does not support the signaling compression. A system that provides protocol multimedia services. 13. The system of claim 12, wherein the address value is an address value of a proxy-call session control function of the internet protocol multimedia subsystem.

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