KR20060033407A - Method for terminating call unregistered user in ip multimedia subsystem network - Google Patents

Abstract

The present invention provides a method for enabling subscriber information inbound call in an IP-based multimedia subsystem, comprising: assigning a server assignment type and a common user ID of the called terminal to request subscriber profile information of a called terminal from a called party S-CSCF; Receiving a SAR message, and if the server assignment type is set to a non-registered user, checking a registration state of the public user ID; and if the check result is registered, associated with the public user ID. Search for the registration of the dedicated user IDs, and include the P-CSCF name list and user profile information of the searched dedicated user IDs in the SAA message and transmit the same to the S-CSCF. If a call occurs, the incoming service does not need to be re-registered by the UE. Because it can provide, it is possible to provide continuous service even in the case of hardware failure of the S-CSCF system.

IMS, I-CSCF, S-CSCF, HSS, SIP, SAA, SAR

Description

METHOOD FOR TERMINATING CALL UNREGISTERED USER IN IP MULTIMEDIA SUBSYSTEM NETWORK}             

1 illustrates the components and interfaces of an IM CN subsystem in an ALL IP core network architecture.

2 is a diagram illustrating a configuration of an S-CSCF performing a subscriber registration function.

3 is a diagram illustrating a UE registration procedure according to a preferred embodiment of the present invention.

4 is a diagram illustrating an incoming call processing procedure according to a preferred embodiment of the present invention.

5 is a diagram illustrating information elements of a SAR message for a registration / deregistration notification request of an S-CSCF according to a preferred embodiment of the present invention.

FIG. 6 is a diagram illustrating information elements of a SAA message for a registered / unregistered notification response of an S-CSCF according to a preferred embodiment of the present invention. FIG.

7 is a flowchart illustrating the procedure of an HSS in accordance with a preferred embodiment of the present invention.

The present invention relates to a next generation IP-based subsystem (Internet Protocol Multimedia Subsystem, hereinafter referred to as 'IMS') network, and more particularly, to a method for enabling subscriber information transmission and reception.

Recently, with the rapid development of mobile communication and the Internet, it is required to realize various multimedia services of high quality for mobile subscribers. The development of the Internet multimedia service required a change from the existing circuit-based next generation core network (hereinafter referred to as 'CN') to the packet-based CN, and further, the IP-based ( Evolving to IP-based CN form. Currently, 3GPP (3Generation Partnership Project) standardizes all IP-based network reference models to provide IM (IP-based Multimedia) services.

The IM service refers to a service capable of simultaneously providing various types of packet-based services based on an IP transport protocol to a mobile subscriber at a lower level. Of course, you can use non-real-time services such as file transfer, e-mail, and short messages at the same time, or use new services such as videophones, instant messaging, emergency calls, etc. ), Local service, presence service, etc. are available.

1 is a diagram illustrating components and interfaces of an IMS network in an ALL IP core network structure.

Referring to FIG. 1, an IM service domain is a call session control function (hereinafter referred to as a 'CSCF') that is responsible for registration and multimedia call processing using a SIP (Session Initiation Protocol) protocol (120, 140). , 150) and a home subscriber server (Home Location Register, hereinafter referred to as HLR) of a legacy mobile network, which integrates functions for mobility management and authentication of IP multimedia users. Subscriber Server, hereinafter referred to as 'HSS'. Let's take a closer look at the signaling protocol and session procedures between CSCF and HSS, which are important factors for IM service, and related functional elements.

Since the CSCFs 120, 140, and 150 have different functions depending on the networks in which the subscribers are located, the Proxy-CSCF (P-CSCF) 120 and the Interrogating-CSCF (I-) are based on their positions and roles. CSCF) 140 and Serving CSCF (S-CSCF) 150 may be logically divided.

The P-CSCF 120 is the first point where a user equipment (hereinafter referred to as 'UE') is connected to the IM multimedia network 100 and is present in the same domain as the Gateway GPRS Support Node (GGSN). The P-CSCF 120 transfers the SIP registration request message received from the UE to the I-CSCF 140 with reference to the home domain of the UE, and the S-CSCF received the SIP message received from the UE through a registration procedure. The address is transmitted to the S-CSCF 150 using the address. In addition, the UE 110 functions to request or respond to a SIP message.

I-CSCF 140 is the first point of access to the home network of the UE (110) may exist several in one network domain. The I-CSCF 140 receives the address of the S-CSCF 150 that performs SIP registration of the UE 110 from the HSS 130 and then allocates an SCSCF in charge of actual registration or receives a SIP received from another network. Route the message to the S-CSCF 150.

The S-CSCF 150 registers that the UE is a session control server of the UE with the HSS 130 and then downloads and stores subscriber information of the UE, and provides information related to service resources while managing session state of the registered UE. , announcement). Obtains the address of the I-CSCF of the home domain of the destination UE 110 through the dialed number of the UE or the SIP URL, and performs authentication with the authentication information received from the HSS 130 at the time of registration of the UE 140. . It can also perform the function of P-CSCF.

The HSS 130 is a master database of subscribers, and is responsible for all information of subscribers for call session control. It includes all the features of the existing 3G HLR, and also contains signaling protocols related to information for IM subscribers for IM services. One or several such HSSs 130 may exist in one same network depending on the number of subscribers and the configuration capability of the network. HSS is a subscriber's master database with basic information related to subscribers, including subscriber identifiers, such as number and address information, subscriber security information, network access control information for authentication and authorization, subscriber location information, registration and inter-system. Level of mobile information and service profile information of the subscriber.

In FIG. 1, when the UE 110 registers with the network, the corresponding S-CSCF 150 stores subscriber information of the UE 110 provided from the HSS 130, and the S-CSCF 150 when a call is requested. ) Connects the incoming call to the UE (110).

2 is a diagram illustrating a configuration of an S-CSCF performing a registration function of a subscriber.

Referring to FIG. 2, a structure in which a plurality of applications 200 performing service processing on a hardware platform of a server farm structure shares a load is illustrated. Applications obtain subscriber information from a plurality of Subscriber Data Managers (hereinafter, referred to as SDMs) 210 and 220 that perform a Register function. Such SDMs have redundant SDBs. SDB1p 213 is a primary node of SDM1 210 and SDB1b 226 located in SDM2 220 represents a backup node of SDM1 210. SDB1p 213 and SDB1b 226 store the same data so that S-CSCF can continue service even if one database fails. However, if the SDM1 210 and the SDM2 220 have a node failure at the same time and the subscriber information of the UE is lost, the service cannot be continued.

The conventional IMS network operating as described above does not consider a method for processing an incoming call for an abnormal state of the S-CSCF. Therefore, when the registration information (Registra) is lost due to a system failure of the S-CSCF, there is a problem that the UE cannot receive the incoming service until re-registration.

Accordingly, an object of the present invention, which was devised to solve the problems of the prior art operating as described above, is a method of normally serving an incoming call to the UE when the subscriber information of the UE is lost due to a system failure of the S-CSCF. To provide.

Another object of the present invention is to provide a method of transmitting a name of a P-CSCF in a message for subscriber registration.

In order to achieve the above object, an embodiment of the present invention provides a method for enabling subscriber information initiation call in an IP-based multimedia subsystem, requesting subscriber profile information of a called terminal from an S-CSCF. Receiving a SAR message including a server assignment type and a public user ID of the called terminal, and if the server assignment type is set to a non-registered user, checking a registration state of the public user ID; If it is registered as a result of the check, it is searched for registration of dedicated user IDs associated with the public user ID, and the P-CSCF name list and user profile information of the searched dedicated user IDs are included in the SA- message. It characterized in that it comprises a process of transmitting to the CSCF.

According to another embodiment of the present invention, in a method for enabling subscriber information inbound and incoming calls in an IP-based multimedia subsystem, when registration of a terminal is required, the S-CSCF allocated to the terminal is determined by the HSS of the terminal. Transmitting a proxy name including a proxy name which is a name of a P-CSCF connected to the user terminal in a SAR message requesting subscriber profile information, and the HSS stores the proxy name for the public and dedicated user IDs of the terminal; And transmitting the SAA message including the entire subscriber profile information of the terminal to the S-CSCF, and storing the subscriber profile information by the S-CSCF.

Hereinafter, the operating principle of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, if it is determined that a detailed description of a known function or configuration may unnecessarily flow the gist of the present invention, the detailed description thereof will be omitted. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

The present invention provides a server assignment request (SAR) or a server assignment answer (SAA) in order to properly perform an incoming call when a failure occurs in the S-CSCF register. It is included in the message. The operation of the present invention consists of an IMS registration procedure of a UE and an incoming call processing procedure for the UE.

3 is a diagram illustrating a UE registration procedure according to a preferred embodiment of the present invention.

In step 301, the UE 350 transmits a registration message to the P-CSCF 360 to register with the IMS. In step 303, the P-CSCF 360 transmits the registration message to the I-CSCF 370. In step 306, the I-CSCF 370 transmits a User Authorization Request (hereinafter referred to as “UAR”) message to the HSS 380. The UAR message is a feasibility study result or performance of the UE 350. Information, such as a list, etc. The HSS 380 checks the UAR message received from the I-CSCF 370, and then the capability of the UE 350 to the I-CSCF 370 in step 309. A User Authorization Answer (hereinafter referred to as "UAA") message indicating the S-CSCF 390 that is appropriate for the request.

In step 311, the I-CSCF 370 transmits a registration message for the UE to the S-CSCF 390. Then, the S-CSCF 390 performs authentication (Authentication) for the UE. In step 313 after successful authentication, the S-CSCF 390 transmits a SAR message requesting subscriber profile information of the UE to the HSS 380. The SAR message includes the name of the P-CSCF 360 to which the UE is connected, that is, a proxy name. HSS 380 stores the proxy name for the public and dedicated user ID of the UE. The HSS 380 receiving the SAR message transmits an SAA message to the S-CSCF 390 in step 315. The SAA message includes subscriber profile information of the UE. Upon receiving the SAA, the S-CSCF 390 stores the subscriber profile information and transmits a 200 (OK) response message to the I-CSCF 370 in step 317. The I-CSCF 370 receiving the response message transmits a 200 (OK) response message to the P-CSCF 360 in step 319, and the P-CSCF 360 receives the response message in step 321. A 200 (OK) response message is sent to the UE to complete the registration procedure of the UE.

4 is a diagram illustrating an incoming call processing procedure according to a preferred embodiment of the present invention.

In step 401, the originating UE (not shown) transmits an INVITE request message requesting an incoming call to the called UE to the S-CSCF # 1 450. After checking the invitation request message, the S-CSCF # 1 450 transmits a 100 (Trying) message to the calling UE in step 403. The S-CSCF # 1 450 transmits the invitation request message to the I-CSCF 460 in step 407. The I-CSCF 460 confirming the invitation request message in step 409 transmits a 100 (Trying) message to the S-CSCF # 1 450. In addition, the I-CSCF 460 transmits a user location information query message to find the S-CSCF of the called UE to the HSS 470 in step 411. In step 411, the HSS 470 responds with information about the S-CSCF # 2 480 registered for the called UE. In step 413, the I-CSCF 460 transmits an invitation message for the called UE to S-CSCF # 2 480. In step 415, the S-CSCF # 2 480 receiving the invitation message transmits a 100 (Trying) message to the I-CSCF 460.                     

The S-CSCF # 2 480 searches its register to find profile information of the called UE. If it finds normally, the called UE connects and connects, and if not found, it is determined that the subscriber information of the called UE is lost or not registered, and in step 417, the HSS 470 is determined by an incoming service procedure of an unregistered subscriber. Send a SAR message.

The SAR includes a public ID of the called UE obtained from the invitation request message of step 413. The HSS finds the subscriber profile information of the called UE and the proxy list of the P-CSCFs using the public ID. In step 419, the HSS sends a SAA message including the proxy list and the subscriber profile information to the S-CSCF # 2 480. Send to. The S-CSCF # 2 480 receiving the SAA message connects to the called UE by using the proxy list and the subscriber profile information.

5 is a diagram illustrating information elements of a registration / non-registration notification request SAR message of an S-CSCF according to a preferred embodiment of the present invention.

As shown, the SAR message includes a public user ID, an S-CSCF name, a P-CSCF name, a dedicated user ID, a server assignment type, user information in use, and routing information.

The public user ID information includes a public user ID or a list of public user IDs, and the S-CSCF name information is a name of an S-CSCF as a server name. The P-CSCF name includes the P-CSCF name in the case of SAR by Proxy-Name AVP registration (when there is no profile of the UE corresponding to the Request-URI in the register of the incoming S-CSCF at the time of initial SIP message processing). . The dedicated user ID information informs the user name. The server assignment type information is S-CSCF update type information in the HSS. For example, the server assignment type information includes information such as whether a non-registered user is set. The user data information in use includes user profile information in use in the S-CSCF, and the routing information indicates the destination host information and stores the name of the HSS.

6 is a diagram illustrating information elements of a registered / unregistered notification response (SAA) message of an S-CSCF according to a preferred embodiment of the present invention.

As shown, the SAA message includes a dedicated user ID, a P-CSCF name, a registration result, a user profile, and billing information. The unique user ID is a user name, the P-CSCF name is a proxy name and the registered state of the public-identity of the SAR message is "registered" and the User-Data-Request-Type AVP value is " UNREGISTERED_PROFILE ", the Proxy-Name AVP contains a P-CSCF list. The registration result is the result code AVP and the experiment result AVP, and the result code is used for fault discovery of the Diameter base protocol, and the experiment result AVP is information indicating a failure of the Cx / Dx interface, which is a connection between the HSS and the CSCF. The user profile represents user information, and the charging information is an address of charging functions including usage information of all other elements, and the user information AVP is transmitted to the S-CSCF.

7 is a flowchart illustrating a procedure of an HSS according to a preferred embodiment of the present invention.

In step 500, if the HSS receives the SAR from the S-CSCF, if the server assignment type (Sever-Assignment-Type) of the SAR message is not set to the unregistered user (UNREGISTERED_USER) in step 505, the HSS proceeds to step 510. The SAA including the full user profile information according to the public and private ID of the SAR message is transmitted to the S-CSCF.

However, if the server assignment type is set to a non-registered user, the flow proceeds to step 515 to check the registration status of the public user ID included in the SAR. If not, the flow proceeds to step 520, the HSS extracts the profile of the unregistered user for the public user ID, in step 530 SA- message including the extracted unregistered user profile S- Send to CSCF.

However, if the public user ID is registered, proceed to step 525 to search for registration of dedicated user IDs associated with the public user ID, and in step 535 proxy names of P-CSCFs registered for the dedicated user IDs. In step 540, the list is transmitted to the SAA, including the user profile information for the public user ID, the dedicated user ID, and the proxy name list.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by those equivalent to the scope of the claims.

In the present invention operating as described in detail above, the effects obtained by the representative ones of the disclosed inventions will be briefly described as follows.

According to the present invention, even when a dual down of a database occurs in an S-CSCF configured as primary / backup, an incoming service can be provided without a UE re-registration procedure. Continuous service can be provided even in the event of a failure.

Claims (4)

What is claimed is: 1. A method for enabling subscriber information inbound call in an IP based multimedia subsystem, Server allocation request including a server allocation type and a public user ID of the called terminal to request subscriber profile information of the called terminal from a serving-call session control function (hereinafter referred to as “S-CSCF”). (Sever Assignment Request, hereinafter referred to as "SAR") the process of receiving a message, If the server assignment type is set to a non-registered user, checking a registration state of the public user ID; If it is registered as a result of the check, it is searched for registration of dedicated user IDs associated with the public user ID, and the proxy call session control function (Proxy-CSCF, hereinafter referred to as “P-CSCF”) for the searched dedicated user IDs. And a name list and all user profile information of the called terminal in a server assignment response (hereinafter referred to as "SAA") message and transmitting the same to the S-CSCF. . The method of claim 1, further comprising: if the server assignment type is not set as an unregistered user, transmitting a SAA message including all user profile information of the called terminal to the S-CSCF. Said method. The method of claim 1, wherein if the public user ID is not registered, And extracting profile information of the non-registered user with respect to the public user ID and transmitting a SAA message including the extracted non-registered user's profile to the S-CSCF. What is claimed is: 1. A method for enabling subscriber information inbound call in an IP based multimedia subsystem, When the registration of the terminal is required, the S-CSCF assigned to the terminal accesses the user terminal to a SAR message requesting subscriber profile information of the terminal to a home subscriber server (hereinafter referred to as a 'HSS'). Including the proxy name, which is the name of the generated P-CSCF, Storing, by the HSS, the public name and the dedicated user ID of the terminal, and transmitting a SAA message including the entire subscriber profile information of the terminal to the S-CSCF; And the S-CSCF stores the subscriber profile information.

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