KR20050103049A - System and method for establishing session with service based local policy - Google Patents

Abstract

The present invention provides a method for establishing a message session through an intermediate node in an IP multimedia subsystem using a service-based regional policy, comprising: a session initiation protocol session with a call session control function and intermediate nodes located between receiving terminals from an originating terminal. Transmitting a byte message, a proxy call session control function connected to a receiving terminal, including a quality of service authentication means in the initialization protocol session message, and transmitting the received message to a receiving terminal, and located between the receiving terminal and the transmitting terminal. Transmitting a response message to the session initiation protocol session invite message to a call session control function and intermediate nodes, setting a transport connection protocol, and a proxy call session control function connected to an originating terminal to the response message. Quality of Service Certification Means Characterized by comprising a process consists of forming the MSRP session message transmission protocol via an intermediate node of the reception terminal from the process, the calling terminal to be transmitted to the calling terminal.

Description

System and Method for establishing session with Service Based Local Policy in IP Multimedia Subsystem using Service Based Local Policy

The present invention relates to a system and method for supporting a multimedia service, and more particularly, to a system and method for forming a session of a receiving terminal through an intermediate node to support session-based messages using a service-based regional policy.

The dissemination of the Internet and mobile communication is remarkable, creating new cultures and industries in our society. As a result of this trend, mobile communication technology of the third generation and later has emerged by integrating closely with Internet technology. Accordingly, an internet terminal having mobility is emerging, and an evolution has been made to a multimedia function mobile communication terminal that enables various media communications as well as the Internet.

According to this trend, researches have been conducted in which the terminal, the base station, and the core network are evolved based on the Internet within their respective areas, and first, the evolution has been attempted from the core network with little direct influence on subscribers. In addition, efforts have been made to introduce IP technology to wireless access networks, and at the same time, researches on IP-based RAN technologies have been conducted in 3GPP and 3GPP2, 3G mobile communication standardization organizations. Evolution itself is composed of a base station, a terminal, and a core network, but their functions are complexly interlinked, and accordingly, it is required to evolve according to the purpose of each other.

Features of the Internet technology include the ease of providing various contents and services provided by the existing Internet network, the sharing of the infrastructure with the Internet network by reusing Internet infrastructure technology, and the use of IP transport technology. There is a lighting that has excellent network flexibility and scalability. On the other hand, as mentioned above, since the problems of the Internet exist as they are, research to solve them must be continuously conducted. Accordingly, the mobile communication system can be completely evolved based on IP.

Among them, IP Multimedia Subsystem (hereinafter referred to as IMS) is a web-based technology for voice, video, message data and wireless user as described above. Proposed to provide IP multimedia services that can be accessed.

The IMS includes a call session control function (CSCF) and a home subscriber server (HSS) as an important function of a core network subsystem for providing a multimedia service.

In the IMS, a Session Initiate Protocol (hereinafter referred to as SIP) is used to provide connectivity with an existing Internet network and independence of an access network. This is a call setup protocol for various services. In addition, a session description protocol (hereinafter referred to as SDP) is used in a SIP message body for negotiating session information, and for a session-based messaging service, a session description protocol (SDP) is used by using a SDP transmitted by SIP. Message Session Relay Protocol (hereinafter referred to as MSRP) is a session used to transmit a series of instant messages.

In addition, the context process of the packet data protocol (hereinafter, referred to as PDP) is used to negotiate a parameter of the QoS, thereby reserving resources.

Meanwhile, in 3GPP, a service based local policy (hereinafter referred to as SBLP) technology has been proposed as a technique for establishing a relationship between a SIP / SDP session level and a bearer level to provide bearer service QoS to an IMS system. . That is, the SBLP is a technology for supporting the components of the objectized core network to be configured as a network for multimedia services according to the location of the terminal.

However, the scheme proposed in the prior art does not use the session-based regional policy as described above, and describes an intermediate node, that is, an application server (AS) and a multimedia resource function controller (MRFC). And a technique for forming a session-based message by a calling terminal in an environment in which a multimedia resource function processor (hereinafter referred to as MRFP) exists.

Therefore, there is a problem that there is no solution when the source terminal lacks resources to host the MSRP session or when the destination terminal attempts to host the MSRP session.

Accordingly, in order to solve the above problems, the present invention provides a system and method for establishing a session by a receiving terminal to provide a session-based messaging service through intermediate nodes in an IP multimedia system using a service-based regional policy. .

It is still another object of the present invention to provide a system and method for supporting QoS for reserving resources in an IP multimedia system using a service-based regional policy.

The present invention for achieving the above object is in the IP multimedia subsystem according to the service-based regional policy, one or more intermediate nodes to form a message session transmission protocol session, transmitting a message transmitted from the transmitting terminal to the receiving terminal And a plurality of call session control functions connected to the terminals and configured to perform a function according to the location of the terminals and to set a session initialization protocol with the intermediate nodes.

In order to achieve the above object, the present invention provides a method for establishing a message session through an intermediate node in an IP multimedia subsystem using a service-based regional policy.

Transmitting a session initiation protocol session invite message to a call session control function and an intermediate node located between a receiving terminal from an originating terminal, and a proxy call session control function connecting to the receiving terminal is connected to the initialization protocol session message. Transmitting a response message to the session initiation protocol session invite message to the receiving terminal by including a quality of service authentication means and transmitting it to the receiving terminal and the call session control function and the intermediate nodes located between the receiving terminal and the receiving terminal. Setting a transmission connection protocol; transmitting, by a proxy call session control function connected to an originating terminal, a service quality authentication means in the response message to the originating terminal; Form a message session transfer protocol Is characterized in that consists of the process.

Hereinafter, the detailed operation and structure of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that reference numerals and like elements among the drawings are denoted by the same reference numerals and symbols as much as possible even though they are shown in different drawings. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

In the present invention, a receiving terminal transmits a message session transmission protocol through an intermediate node in an IP multimedia subsystem using a service-based local policy (hereinafter referred to as SBLP). Suggest technology for hosting sessions.

Next, an embodiment of a configuration diagram of an IP multimedia subsystem using a service area based policy for applying the technical contents proposed by the present invention as described above will be described with reference to FIG. 1.

In FIG. 1, the UEs 111 and 143 move from their home networks to a visited network in an environment in which a service-based regional policy is supported.

In addition, in FIG. 1, a first external network (UE # 1 VISITED NETWORK) 110 and a first home network (UE # 1 HOME NETWORK) 120 are connected to a first terminal (User Equipment: UE # 1) 111. A first service provider network for providing a communication service, and a second external network (UE # 1 VISITED NETWORK) 130 and a second home network (UE # 1 HOME NETWORK) 140 is a second terminal (User Equipment: UE) As a second provider network for providing a communication service to # 2) 143, the first provider network and the second provider network may have different forms.

Referring to FIG. 1, the IP multimedia system using a service area based policy includes a plurality of call session control functions (hereinafter referred to as CSCFs) in which functions performed by a terminal according to location are logically divided. , 121, 131, 134, and 141, and intermediate nodes 125 and 138 in which an MSRP session for transmitting a message from the first terminal 111 to the second terminal 143 are formed.

In addition, a policy decision function (hereinafter referred to as PDF) 145 interfaces with the second P-CSCF 141 to provide a service-based regional policy, and a serving GPRS support node for packet data transmission. Serving GPRS Support Node (hereinafter referred to as SGSN) 149 and Gateway GPRS Support Node (hereinafter referred to as GGSN) 147 are shown.

The CSCF is a proxy call session control function (Proxy-CSCF: hereinafter referred to as P-CSSF) (115, 141), serving call session control function (Serving-CSCF: hereinafter referred to as S-CSCF) (121, 134) and a query call session control function (Interrogating-CSCF: hereinafter referred to as I-CSCF) 131.

First, as illustrated in FIG. 1, the P-CSCFs 115 and 141 are located in an external or home network 110 and 140, and are the first devices to be connected when the terminals 111 and 143 receive an IMS service. . The S-CSCFs 121 and 134 are located in the home networks 120 and 130 to process SIP sessions of the terminals 111 and 143. The second I-CSCF 131 is located at the point of contact between the other operator networks to serve as a relay between the two networks. Referring to FIG. 1, the first I-CSCF 131 is located in the first home network 120. ) And the second S-CSCF 134 located in the second home network 130 support establishing a session. In addition, although FIG. 1 illustrates that the second I-CSCF 131 is located only in the second home network 130, the I-CSCF may be located in the first home network 120.

The intermediate nodes 125 and 138 may be AS, MRFC, or MRFP, and actual packet data is transmitted through the intermediate nodes. In FIG. 1 the intermediate node is shown as an AS. That is, the MSRP session for transmitting the actual message is between the first terminal 111 and the first AS 125 (M1), between the first AS 125 and the second AS 138 (M2), and the second AS. 138 and a second terminal 143 is formed between (M3), this MSRP session establishment is negotiated through the SDP.

In particular, the present invention proposes a process in which the second terminal 143 as the receiving terminal hosts the MSRP session when the first terminal 111 as the originating terminal cannot host the MSRP session for the session-based message.

In order to form the MSRP session as described above, a SIP session should be established between the CSCF and the AS first. According to the SIP INVITE request of the first terminal 111, the first terminal 111 and the first P-CSCF ( 115 between (S1), between the first P-CSCF 115 and the first S-CSCF 121 (S2), and between the first S-CSCF 121 and the first AS 125 (S3). The SIP session is then established. At this time, the AS 125 adds its location to the record route for future transactions, for example for a pre-pay service.

In addition, SIP sessions are formed in the order of S4, S5, S6, S7, and S8, which will be described in detail with reference to other exemplary embodiments of the present invention with reference to FIGS. 2A through 2C.

In addition, Q1 and Q2 illustrated in FIG. 1 are processes for adjusting a Quality of Service (QoS) policy, and use a policy-based regional policy to describe a policy decision function unit (hereinafter referred to as PDF). 145 emerges as an important component.

The second P-CSCF 141 is linked with the PDF 145 for policy based admission adjustment. The PDF 145 provides service based policy coordination for access to IMS services. In addition, the PDF 141 adjusts the UE-Initiated bearer formation process by adjusting a resource management request input to the GGSN 147 through the Go interface. Q1 is an interface based on the Common Open Policy Service (hereinafter referred to as COPS). This allows the operator to be involved in the policy for the PDP context in the GGSN 147. Q2 is a Gq interface, which is to negotiate QoS policy coordination like Q1.

B1 and B2 activate the PDP context. Knowing the characteristics of the media, such as QoS and bandwidth, the second P-CSCF 141 connects with the PDF 145 to obtain the authentication authority for the session resource and the authentication token generated in the PDF 145. . This media authentication token is sent in the body of the response message sent to the terminal 143 to create a SIP session. Thereafter, the GGSN 147, which has received a request from the terminal to activate the PDP context, requests the PDF 145 to authenticate the bearer through the Go interface using an authentication token. The PDF 145 then instructs the GGSN 147 to use the authenticated QoS resources.

150 shows External Network and E1 shows External IP Network in GGSN.

Next, a method of hosting an MSRP session by a receiving terminal on the system as described above will be described with reference to FIGS. 2A to 2C.

Here, it will be described on the premise that a receiving terminal hosts an MSRP session when there is an intermediate node using a service based local policy without using a precondition proposed in the present invention.

The message transmitted below is divided into three categories. FIG. 2A illustrates a process of transmitting a Session Initiate Protocol (hereinafter referred to as SIP) message, and FIG. 2B illustrates a transport protocol message. 2c shows a process of transmitting a message session relay protocol (hereinafter referred to as MSRP) message.

Referring to FIG. 2A, steps 1 through 24 correspond to a SIP session establishment process of steps S1 to S8 illustrated in FIG. 1, wherein a session initialization protocol invite (hereinafter referred to as SIP INVITE) message is provided. The process is transmitted from the first terminal 111 to the second terminal 143.

The first terminal 111 transmits the SIP INVITE message to the first P-CSCF 115 in step 1. In the SDP transmitted together with the SIP INVITE message, the directionality of the MSRP is set to an active state. This is to host the MSRP session in the second terminal (143).

The first P-CSCF 115 transmits the 100 attempt response to the SIP INVITE message of the first step to the first terminal 111 in step 2. The 100 attempt response is the same as the SIP proxying method. The first P-CSCF 115 transmits a SIP INVITE message to the first S-CSCF 121 as in step 1 in step 3, and the first S-CSCF 121 sends the second step in step 4 As shown in FIG. 100, a 100 attempt response to the SIP INVITE message is transmitted to the first P-CSCF 115.

In step 5, the first S-CSCF 121 transmits a SIP INVITE message to another CSCF or an application server according to an initial filtering criterion. In this case, it is assumed that the data is transmitted to the first AS 125.

In step 6, the first S-CSCF 121 sends a SIP INVITE message to the first AS 125, and the first AS 125 sends a 100 attempt response to it in step 7, It's the same way. The first AS 125 generates a new SIP INVITE message and transmits it to the first S-CSCF 121 in step 8. In step 9, the challenge response transmitted by the first S-CSCF 121 is the same as that of the SIP proxy.

In step 12, the second I-CSCF 121 sends a query to the home participant server (HSS) to find the second S-CSCF 124 located in the second home network. In step 13, the second I-CSCF 121 transmits the SIP INVITE message to the found second S-CSCF 124. Then, in step 14, the challenge response transmitted by the S-CSCF 124 is the same as that of the SIP proxy.

In step 15, the second S-CSCF 124 transmits a SIP INVITE message to another CSCF or an application server according to the initial filtering criteria. In this case, the second AS 128 is transmitted.

The second S-CSCF 124 generates a new SIP INVITE message and transmits it to the second AS 128 in step 16. The challenge response sent by the second AS 128 in step 17 is the same as that of the SIP proxy. The second AS 128 generates a new SIP INVITE message in step 18 and sends it to the second S-CSCF 124, which in turn is sent to the second P-CSCF 141 in step 20. At step 19 and 21, the challenge response is the same as that of the SIP proxy.

The second P-CSCF 141 includes the QoS authentication token in the SIP INVITE message in step 22. Then, in step 23, the second P-CSCF 141 transmits the SIP INVITE message including the QoS authentication token to the second terminal 143. At step 24, the challenge response is the same as that of the SIP proxy.

Referring to FIG. 2B, in steps 25 to 40, a transport protocol message is transmitted, and the MSRP session is hosted by the second terminal 143, which is a receiving terminal.

In step 25, the second terminal 143 allocates an IP-Connectivity Access Network bearer (hereinafter referred to as IP-CAN Bearer).

In steps 26 to 28, a 200 OK message is transmitted. The included SDP answer sets the directionality of the MSRP to Passive, and sets the TCP port number and the URL for the MSRP session. According to the value set here, TCP setup from the second terminal 143 to the second AS 128 is performed in step 29.

In step 30 to 33, 200 OK message is transmitted. The included SDP answer sets the directionality of the MSRP to Passive, and sets the TCP port number and the URL for the MSRP session. The TCP set up from the second AS 128 to the first AS 125 is performed in step 34 by the value set here.

In step 35 and 36 a 200 OK message is sent. At this time, the included SDP answer (password) is set to the direction of the MSRP (Passive), the TCP port number and the URL for the MSRP session is set. By the value set here, in step 37 the QoS authentication token from the first AS 125 to the first terminal 111 is included in the 200 OK response to the INVITE message.

In step 38, the first P-CSCF 115 transmits a 200 OK message including the QoS authentication token to the first terminal 111. The included SDP answer sets the directionality of the MSRP to Passive, and sets the TCP port number and the URL for the MSRP session. The value set here enables TCP setup from the first AS 125 to the first terminal 111. In step 39, the first terminal 111 allocates an IP-CAN bearer using the received session URL. In step 40, a TCP setup from the first terminal 111 to the first AS 125 is performed.

Referring to Figure 2c, step 41 to 61 is a process of forming an MSRP session through the intermediate node corresponding to the process from M1 to M3 of FIG.

In steps 41 to 43, the VISIT message for the MSRP session is transmitted from the first terminal 111 to the second terminal 143 via the first AS 125 and the second AS 128. Then, in steps 44 to 46, the second terminal 143 transmits a 200 OK message to the first terminal 111 via the second AS 128 and the first AS 125.

In steps 47 to 55, each component transmits an ACK message for the SIP message, and in steps 56 to 61, each component transmits the SEND and 200 OK messages of the MSRP.

As described above, the present invention can provide a framework for a more general quality of service (QoS) and policy, and has an effect of facilitating the introduction of a new service, and a packet streaming service. Service-based adjustment is possible from the operator's point of view on access to services, including third-party services.

On the other hand, the present invention has the effect of enabling the messaging service even when the calling terminal can not maintain the session or when the receiving terminal wants to attract the session.

1 is a block diagram of an IP multimedia subsystem using a service-based regional policy according to an embodiment of the present invention;

2A to 2C are signal flow diagrams illustrating a method for establishing a session by a receiving terminal in an IP multimedia subsystem using a service based local policy according to an exemplary embodiment of the present invention.

Claims (6)

In an IP multimedia subsystem comprising a transmitting terminal and at least one intermediate node linking the transmitting terminal and the receiving terminal and using a service-based regional policy, Confirming that the transmitting terminal has the capability to attract a session; And if the transmitting terminal is not capable of attracting a session, the receiving terminal attracts a session and forms a session. In the IP multimedia subsystem according to the service based regional policy, One or more intermediate nodes for establishing a message session transmission protocol session, for transmitting a message transmitted from a transmitting terminal to a receiving terminal; And a plurality of call session control functions connected to the terminals and configured to perform a function according to the location of the terminals and to establish a session initiation protocol with the intermediate nodes. 3. The method of claim 2, wherein the call session control functions are Proxy call session control functions for connecting to the terminals; Serving call session control functions for receiving a session initiation protocol invite message from the proxy call session control function and transmitting the received message to the intermediate node; And a call call session control function for transmitting the initialization protocol invite message to a serving call session control function located in a different type of network. A method for establishing a message session through an intermediate node in an IP multimedia subsystem using service based local policy, Transmitting a session initiation protocol session invite message to a call session control function and intermediate nodes located between a receiving terminal from an originating terminal, Transmitting, by a proxy call session control function, which is connected to a receiving terminal, a quality of service authentication means in the initialization protocol session message to a receiving terminal; Transmitting a response message to the session initiation protocol session invite message to a call session control function unit and intermediate nodes located between the receiving terminal and the transmitting terminal, and setting a transmission connection protocol; Transmitting, to the calling terminal, a proxy call session control function connected to the calling terminal by including a quality of service authentication means in the response message; And forming a message session transfer protocol from the originating terminal to an intermediate node of the receiving terminal. 5. The method of claim 4 wherein the session initiation protocol invite message is And the message is set together with a message which sets the directionality of the message service transmission protocol to an active state. 5. The method of claim 4, wherein sending a session initiation protocol invite message The serving call session control function located in the home network transmits to an intermediate node located in the same home network.