KR101173836B1 - Method for processing termination and origination call after repairing s-cscf failure in internet protocol multimedia subsystem network and system of the same - Google Patents

Abstract

PURPOSE: A method for processing terminating and originating calls after repairing an S-CSCF failure in an internet protocol multimedia subsystem network and a system thereof are provided to simplify a processing procedure between an HSS(Home Subscribe Server) and an S(Serving)-CSCF(Call Session Control Function) by sorting termination and origination of incoming calls from a terminal. CONSTITUTION: An originating terminal transmits a session initiation request message to an I(Interrogating)-CSCF(Call Session Control Function)(130) passing through an originating PCSCF(Proxy-CSCF)(110) and an originating S-CSCF(120). An HSS(150) stores and manages a subscriber profile and authentication and position related data. A location information request message is transmitted to the HSS in order to search the subscriber profile including an address of a terminating S-CSCF(140). The HSS transmits the location information response message, including the location information of the originating S-CSCF corresponding to an LIR(Location Information Request) message, to the I-CSCF.

Description

METHODO FOR PROCESSING TERMINATION AND ORIGINATION CALL AFTER REPAIRING S-CSCF FAILURE IN INTERNET PROTOCOL MULTIMEDIA SUBSYSTEM NETWORK AND SYSTEM OF THE SAME}

The present invention relates to an Internet protocol Multimedia Subsystem (IMS) network technology, and more particularly, to a method and a system for handling incoming and outgoing calls after S-CSCF failure recovery in an IMS network.

IMS (IP Multimedia Subsystem) is a network technology that integrates wired and wireless environments and is an infrastructure to provide multimedia services such as voice, audio, video, and data based on the 3rd generation mobile communication network IP (Internet Protocol). Because IMS is based on Internet protocol, it uses a packet switched based unfixed call path to increase transmission efficiency and ensure stability. These IMSs can support not only simple one-to-one calls, but also connections involving multiple users.

One of the devices constituting the IMS network, the CSCF (Call Session Control Function) is a device that controls the entire session in the IMS network. CSCFs include P (Proxy) -CSCF, I (Interrogating) -CSCF, and S (Serving) -CSCF. At this time, if a failure occurs in the S-CSCF while the session is established and the call is transmitted in the IMS network, when the failure of the S-CSCF is recovered, both the subscriber information and the existing session information managed by the S-CSCF are lost. Therefore, when the S-CSCF fails in the IMS network, the S-CSCF after restoring the S-CSCF cannot determine whether the incoming call from the terminal is an outgoing or incoming call, so that the subscriber of the terminal cannot receive the outgoing or incoming service. do.

Accordingly, an object of the present invention is to determine whether a new S-CSCF or a repaired S-CSCF is an originating or incoming call when an S-CSCF fails in an IMS network and determines whether the incoming call is received or received. Another object is to provide a method and a system for handling incoming and outgoing calls after S-CSCF failure recovery in an IMS network capable of efficiently providing an incoming service.

In the IMS network according to the present invention, a method for processing an incoming call after S-CSCF failure recovery may include: (Interrogating) -CSCF transmitting a session start request message to a first incoming S-CSCF in which a called terminal is registered, and within a preset time period. Determining that the first incoming S-CSCF is in an error state when a response message is not received from the first incoming S-CSCF; The I-CSCF performing a location information request (LIR) message and a location information response (LIA) message exchange with an HSS and sending a session initiation request message to an assigned second incoming S-CSCF; The second incoming S-CSCF receiving the session initiation request message performs a server assignment request (SAR) message and a server assignment response (SAA) message exchange with the HSS to request a session initiation with the incoming P (Proxy) -CSCF. And sending the message.

According to an embodiment of the present invention, a method for processing an incoming call after recovering from an S-CSCF failure in an IMS network is a computer program for executing an incoming call processing method after recovering from an S-CSCF failure in an IMS network stored in a computer-readable recording medium. Can be implemented by executing

In an IMS network according to the present invention, an outgoing call processing method after S-CSCF failure recovery may include an I (Interrogating) -CSCF transmitting a session initiation request message to a first outgoing S-CSCF in which an originating terminal is registered, and within a preset time. Determining that the first originating S-CSCF is in a failure state when a response message is not received from the first originating S-CSCF; The I-CSCF performing a location information request (LIR) message and a location information response (LIA) message exchange with an HSS and sending a session initiation request message to an assigned second originating S-CSCF; And the second originating S-CSCF receiving the session initiation request message exchanges a server assignment request (SAR) message and a server assignment response (SAA) message with the HSS to transmit a session initiation request message to the I-CSCF. It may include the step.

An outgoing call processing method after S-CSCF failure recovery in an IMS network according to an embodiment of the present invention is a computer program for executing the outgoing call processing method after S-CSCF failure recovery in the IMS network stored in a computer-readable recording medium. Can be implemented by executing

In the IMS network according to the present invention, an incoming and outgoing call processing system after S-CSCF failure recovery transmits a session start request message to a first S-CSCF in which a terminal is registered, and transmits a session start request message from the first S-CSCF within a predetermined time. If the response message is not received, it is determined that the first S-CSCF is in a failure state, and exchanges a location information request (LIR) message and a location information response (LIA) message with the HSS to request a session initiation with the assigned S-CSCF. I (Interrogating) -CSCF for sending a message; And a second S-CSCF that receives the session initiation request message and exchanges a server assignment request (SAR) message and a server assignment response (SAA) message with the HSS.

According to the method and system for incoming and outgoing call processing after the S-CSCF failure recovery in the IMS network according to the present invention, when the failure of the S-CSCF, the new S-CSCF or the S-CSCF that has been recovered from the failure is the incoming and outgoing of the incoming call from the terminal. Calls can be handled separately.

In addition, according to the present invention, according to the method and system for incoming and outgoing call processing after the S-CSCF failure recovery in the IMS network, a new S-CSCF or a procedure between the S-CSCF and the HSS in which the failure is recovered when the S-CSCF fails Can be simplified.

1 is a block diagram illustrating an IMS network according to an embodiment of the present invention.
2 is a flowchart illustrating a call processing process when failing over an incoming S-CSCF according to 3GPP specifications.
3 is a flowchart illustrating a call processing process when failing over an incoming S-CSCF according to an embodiment of the present invention.
4 is a flowchart illustrating a call processing procedure when failing back to an originating S-CSCF in an AS origination according to the 3GPP specification.
5 is a flowchart illustrating a call processing process when failing back to an originating S-CSCF in an AS origination according to an embodiment of the present invention.
6 is a flowchart illustrating a process of determining a recovery parameter by I-CSCF according to an embodiment of the present invention.
7 is a flowchart illustrating a process of determining a Server-Assignment-Type AVP value by an S-CSCF according to an embodiment of the present invention.
8 is a flowchart illustrating a call processing process based on a Server-Assignment-Type AVP value according to an embodiment of the present invention.

Specific structural and functional descriptions of the embodiments of the present invention disclosed herein are for illustrative purposes only and are not to be construed as limitations of the scope of the present invention. And should not be construed as limited to the embodiments set forth herein or in the application.

The embodiments according to the present invention are susceptible to various changes and may take various forms, so that specific embodiments are illustrated in the drawings and described in detail in this specification or application. However, this is not intended to limit the embodiments in accordance with the concept of the present invention to a particular disclosed form, it should be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the present invention.

The terms first and / or second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are intended to distinguish one element from another, for example, without departing from the scope of the invention in accordance with the concepts of the present invention, the first element may be termed the second element, The second component may also be referred to as a first component.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between. Other expressions describing the relationship between components, such as "between" and "immediately between," or "neighboring to," and "directly neighboring to" should be interpreted as well.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, the terms "comprises ", or" having ", or the like, specify that there is a stated feature, number, step, operation, , Steps, operations, components, parts, or combinations thereof, as a matter of principle.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art, and are not construed in ideal or excessively formal meanings unless expressly defined herein. Do not.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the preferred embodiments of the present invention with reference to the accompanying drawings. Like reference numerals in the drawings denote like elements.

1 is a block diagram illustrating an IMS network according to an embodiment of the present invention. Referring to FIG. 1, an Internet Protocol Multimedia Subsystem (IMS) network 1000 to which the present invention is applied may include a Call Session Control Function (CSCF) server, a recovery parameter determination device 500, a Home Subscribe Server (600), and an SLF. (Subscription Locator Function 700) and AS (Application Server, 800).

The user equipment (UE) 100 or 101 may be a wireless terminal usable in the IMS network 1000.

The CSCF server may perform basic functions for session initiation protocol (SIP) based multimedia session control such as subscriber registration, authentication, service triggering, routing, various call control, and address handling. It can also provide SIP signaling and state management functions.

On the other hand, the CSCF server is a proxy CSCF (Proxy-CSCF; P-CSCF, 200, 201), serving CSCF (Serving-CSCF; S-CSCF, 300), and interrogating CSCF (Interogating-CSCF; I-CSCF, 400). It may include.

P-CSCF (200, 201) is the first point that the terminal accesses the IMS. When a register request message (REGISTER) is transmitted from the terminal, the P-CSCF may deliver it to the I-CSCF. The P-CSCF may store the address of the S-CSCF allocated in the process of processing the registration request message and forward the S-CSCF to the S-CSCF when an INVITE request message (INVITE) is received from the terminal.

The I-CSCF 400 obtains an address list of the S-CSCF 300 available from the HSS 600 in the process of registering a user of the terminal, that is, a subscriber, and refers to the S-CSCF to be in charge of actual registration. You can decide. In this case, when a failure occurs in the determined S-CSCF, the I-CSCF 400 may acquire a recovery parameter in association with the recovery parameter determining apparatus 500. A detailed process thereof will be described later with reference to FIGS. 6 to 7.

When the registration request message is received from the I-CSCF 400, the S-CSCF 300 may register a subscriber with the HSS 600 and obtain a subscriber profile from the HSS 600. The S-CSCF 300 performs a control service while managing a session state of an actually registered user. The S-CSCF 300 also provides information related to service resources to the user.

The HSS 600 may store and manage subscriber profile, authentication, and location related data as a subscriber's master database, and provide information required by the CSCF. In addition, the HSS 600 may generate an authentication vector required for subscriber authentication, and may include a function of a home location register (HLR, not shown).

The subscription locator function (SLF) 700 provides an appropriate HSS address to the CSCF when two or more HSSs 600 are operated in the IMS network 1000 and each is recognized as a separate address.

The AS 800 is an application server and is an entity for providing an application to a user such as Push To Talk over Celluar using an email or a mobile device.

In FIG. 1, the IMS network 1000 includes an S-CSCF 300, an I-CSCF 400, an HSS 600, an SLF 700, and the like. However, this is an IMS node required for implementing the present invention. However, the present invention is not limited thereto, and the IMS network 1000 may include a plurality of devices or servers shown in the drawings.

That is, in FIG. 1, only one S-CSCF 300 and one I-CSCF 400 are shown, but the called party and the calling party may share one S-CSCF and I-CSCF, respectively, each of which is a separate S-CSCF. I-CSCF may be used. The embodiments of the present invention are assumed to be provided with S-CSCF and I-CSCF of the called party and the calling party, respectively, for convenience of description.

2 is a flowchart illustrating a call processing process when failing over an incoming S-CSCF according to 3GPP specifications. Referring to FIG. 2, the originating terminal UE # 1 transmits a session initiation request (INVITE) message to initiate a SIP session with the terminating terminal UE # 2 and the originating P-CSCF 110 and the originating S-CSCF 120. And transmits to the I-CSCF (130) (S101 to S103).

The I-CSCF 130 includes a subscriber profile including the address of the destination S-CSCF 140 in which the called terminal UE # 2 is registered in the HSS 150 that stores and manages the subscriber profile, authentication, and location related data. In order to retrieve the location information request (Location Information Request (hereinafter LIR)) message is transmitted to the HSS 150 (S104), the HSS 150 sends the location information of the incoming S-CSCF 140 corresponding to the LIR message A Location Information Answer (LIA) message is transmitted to the I-CSCF 130 (S105). The I-CSCF 130 transmits a session start request (INVITE) message to the incoming S-CSCF 140 based on the location information of the incoming S-CSCF 140 included in the LIA message (S106).

At this time, the I-CSCF 130 transmits a session initiation request (INVITE) message to the incoming S-CSCF 140 and if the message is not processed even after exceeding a predetermined time by the transaction timer, the incoming S-CSCF ( In operation 140, it is determined that a failure has occurred and a LIR message is transmitted to the HSS 150 to search for another S-CSCF and transmit a call.

The HSS 150 then sends an LIA message to the I-CSCF 130 including an S-CSCF capability list from which it can select another S-CSCF address or another S-CSCF address in response to the LIR message. It transmits (S108).

The I-CSCF 130 selects a new incoming S-CSCF based on the information transmitted from the HSS 150, and transmits a session start request (INVITE) message to the selected incoming S-CSCF 140 '(S109). .

The incoming S-CSCF 140 'may determine whether the incoming or outgoing call is introduced to the incoming S-CSCF 140' based on the session initiation request (INVITE) message transmitted from the I-CSCF 130. The incoming S-CSCF 140 'is unable to determine whether the incoming or outgoing call is coming from the incoming terminal because UE # 2 is not registered in its registration information. Server-Assignment- Type) AVP value is set to "NO_ASSIGNMENT" to transmit a Server Assignment Request (SAR) message to the HSS 150 (S110).

The HSS 150 storing and managing a plurality of called S-CSCFs corresponding to a plurality of called terminals receives a SAR message when a Server-Assignment-Type AVP value is set to "NO_ASSIGNMENT". In response to # 2), a SAR message is received from an incoming S-CSCF 140 'other than the previously registered incoming S-CSCF 140, thereby determining that the incoming S-CSCF 140' is recovered. The HSS 150 transmits a SAA message including subscriber profile and recovery information corresponding to the called terminal UE # 2 to the called S-CSCF 140 '(S111). In this case, the recovery information may include location information of the called terminal UE # 2.

Then, the called S-CSCF 140 'transmits the session start request (INVITE) message to the called terminal UE # 2 via the called P-CSCF 160 (S112 to S113). ) And a call terminal (UE # 2) is connected.

3 is a flowchart illustrating a call processing process when failing over an incoming S-CSCF according to an embodiment of the present invention. Since steps S201 to S208 of FIG. 3 are processed in the same manner as steps S101 to S108 shown in FIG. 2, detailed description thereof will be omitted.

Before the I-CSCF 130 performs an LIR message and an LIA message exchange with the HSS 150 and transmits a session initiation request (INVITE) message to the assigned destination S-CSCF 140 ', the recovery parameter determination device ( By interworking with 500, a recovery parameter that can be set in the URI parameter of the header of the top route of the I-CSCF 130 can be obtained. In this case, an example of a method of determining a recovery parameter is illustrated in FIG. 6.

6 is a flowchart illustrating a process of determining a recovery parameter by I-CSCF according to an embodiment of the present invention. Referring to FIG. 6, the I-CSCF 130 transmits a route set including a plurality of route headers to be transmitted to the destination S-CSCF in a next step, to the recovery parameter determining device 500, and the recovery parameter determining device 500. ) Receives the route set and determines whether a route header exists (S501). For example, the Route header is transmitted in the following format.

Route: <sip: scscf.co.kr; lr>

As a result of the determination in step S501, if the route header does not exist, the "r-term" parameter, which is a recovery parameter, is added to the top Route header and transmitted to the I-CSCF 130 (S507). It is determined whether the "orig" parameter exists in the top Route header of the I-CSCF 130 (S503). For example, if the "r-term" parameter is added, the top Route header is transmitted in the following format.

Route: <sip: scscf.co.kr; lr>; r-term

As a result of the determination in step S503, when the "orig" parameter does not exist in the top Route header, the "r-term" parameter is added to the top Route header and transmitted to the I-CSCF 130 (S507), and in the top Route header If the "orig" parameter exists, add the "r-orig" parameter to the top Route header, or change to the "r-orig" parameter instead of the "orig" parameter in the top Route header to transmit to the I-CSCF (130) (S505). For example, when the "r-orig" parameter is added, the top Route header is transmitted in the following format.

Route: <sip: scscf.co.kr; lr>; orig; r-orig

In addition, when changed to the "r-orig" parameter, the top Route header is transmitted in the following format.

Route: <sip: scscf.co.kr; lr>; r-orig

In this case, the recovery parameter determination apparatus 500 may be implemented outside the I-CSCF 130 to interwork with the I-CSCF 130 or may be implemented inside the I-CSCF 130.

That is, the I-CSCF 130 performs the determination process and then, upon transmitting the session start request (INVITE) message to the destination S-CSCF 140 ', based on the recovery parameter transmitted from the recovery parameter determination apparatus 500. The URI parameter of the top Route header is set to "r-term" and transmitted (S209).

For this purpose, prior to the implementation of the present invention, recovery parameters may be defined in the RFC specification as described in Table 1. That is, based on the determination result of the recovery parameter determining apparatus 500, the I-CSCF indicates "r-" in the top Route header when the failed S-CSCF or the new S-CSCF is an S-CSCF for performing outgoing call processing. orig "and transmit, and in case of S-CSCF for performing incoming call processing," r-term "may be set and transmitted in the top Route header.

uri-parameter = transport-param / user-param / method-param / ttl-param / maddr-param / lr-param / orig / other-param / restoration - param
restoration - param = "r- orig " / "r- term "

Referring again to FIG. 3, the incoming S-CSCF 140 ′ may be configured as a failure of the existing incoming S-CSCF 140 based on the “r-term” parameter set in the top Route header transmitted from the I-CSCF 130. Recognizing that the situation is due to recover, and sets the Server-Assignment-Type AVP value to "SCSCF_RESTORATION" to transmit the SAR message to the HSS (150) (S210).

To this end, "SCSCF_RESTORATION" to indicate the recovered state of the S-CSCF prior to the implementation of the present invention may be added to the Server-Assignment-Type AVP value, which is described in Table 2 as 3GPP. (3rd Generation Partnership Project) Technical Specification (TS), i.e., TS 23.380 (IMS Restoration Procedures), TS 24.229 (IP multimedia call control protocol based on Session Initiation Protocol (SIP) and Session Description Protocol (SDP); Stage 3 ) And TS 29.229 (Cx and Dx interface based on the Diameter protocol).

NO_ASSIGNMENT (0)
REGISTRATION (1)
RE_REGISTRATION (2)
UNREGISTERED_USER (3)
TIMEOUT_DEREGISTRATION (4)
USER_DEREGISTRATION (5)
TIMEOUT_DEREGISTRATION_STORE_SERVER_NAME (6)
USER_DEREGISTRATION_STORE_SERVER_NAME (7)
ADMINISTRATIVE_DEREGISTRATION (8)
AUTHENTICATION_FAILURE (9)
AUTHENTICATION_TIMEOUT (10)
DEREGISTRATION_TOO_MUCH_DATA (11)
AAA_USER_DATA_REQUEST (12)
PGW_UPDATE (13)
SCSCF _ RESTORATION (14)

At this time, in step S210, an example of a process for the incoming S-CSCF (140 ') to set the Server-Assignment-Type AVP value is shown in FIG. 7 is a flowchart illustrating a process of determining a Server-Assignment-Type AVP value by an S-CSCF according to an embodiment of the present invention. Referring to FIG. 7, the recovered S-CSCF determines whether a "r-orig" parameter exists in the transmitted top route header (S601).

As a result, when the "r-orig" parameter is present in the top Route header, the S-CSCF determines that the situation has been recovered due to the failure of the existing S-CSCF, and transmits the SAR message set to "SCSCF_RESTORATION" to the HSS (S607). If the "r-orig" parameter does not exist in the top Route header, it is determined whether the "r-term" parameter exists in the top Route header (S603).

As a result of the determination, when the "r-term" parameter exists in the top Route header, the step S607 is performed. When the "r-term" parameter does not exist in the top Route header, the SAR message set to "NO_ASSIGNMENT" is transmitted to the HSS. (S605).

That is, when performing steps S601 to S607 before step S210, the called S-CSCF 140 'determines whether the "r-orig" parameter exists in the top Route header, and as a result, "r-orig" in the top Route header. Since the "r-term" parameter rather than the "parameter" exists, the incoming S-CSCF 140 'determines that the situation has been recovered due to the failure of the existing S-CSCF 140, and the HSS (SAR message set to "SCSCF_RESTORATION") is determined. 150).

Then, when receiving the SAR message in which the Server-Assignment-Type AVP value is set to "SCSCF_RESTORATION", the HSS 150 receives the registered S-CSCF 140 corresponding to the called terminal UE # 2. Recognizing that is a failure situation and transmits a SAA message including the subscriber profile and recovery information corresponding to the destination terminal (UE # 2) to the destination S-CSCF (140 ') (S211). In this case, an example of a process in which a call is processed by a server-assignment-type AVP value is illustrated in FIG. 8. 8 is a flowchart illustrating a call processing process based on a Server-Assignment-Type AVP value according to an embodiment of the present invention. Referring to FIG. 8, the HSS determines whether a Server-Assignment-Type AVP value transmitted from the recovered S-CSCF is set to "SCSCF_RESTORATION" (S701).

As a result of determination, when the Server-Assignment-Type AVP value is "SCSCF_RESTORATION", the HSS transmits a SAA message including subscriber profile and recovery information corresponding to the calling terminal or the called terminal to the recovered S-CSCF. In operation S703, when it is not "SCSCF_RESTORATION", steps S110 to S111 shown in FIG. 2 are performed.

That is, if the steps S701 to S703 are performed before the step S211, the HSS 150 sets the Server-Assignment-Type AVP value transmitted from the incoming S-CSCF 140 'to "SCSCF_RESTORATION". If the SAA message including the subscriber profile and recovery information corresponding to the called terminal UE # 2 is transmitted to the called S-CSCF 140 ', and is not set to "SCSCF_RESTORATION", S110 to S111 shown in FIG. Will perform the steps.

The receiving S-CSCF 140 ′ having received the SAA message transmits a session start request (INVITE) message to the called terminal UE # 2 via the receiving P-CSCF 160 (S212 to S213). A call is connected between UE # 1 and a called terminal UE # 2.

4 is a flowchart illustrating a call processing procedure when failing back to an originating S-CSCF in an AS origination according to the 3GPP specification. Components of the IMS network are the same as those shown in FIGS. 2 to 3, and in FIG. 4, processes before the AS will be omitted to explain the call processing in the AS origination.

When the originating call flows from the originating terminal UE # 1 to the AS (Application Server 210), the AS 210 adds an "orig" parameter to the top Route header and requests the session initiation to the I-CSCF 220 (INVITE). Message (S301), the I-CSCF 220 sends an HSS (S) to retrieve a subscriber profile including the address of the originating S-CSCF 230 in which the originating terminal UE # 1 is registered in the HSS 250. In step S302, an LIR message is transmitted.

The HSS 250 transmits a LIA message including the location information of the originating S-CSCF 230 corresponding to the LIR message to the I-CSCF 220 (S303). The I-CSCF 220 transmits a session initiation request (INVITE) message to the originating S-CSCF 230 based on the location information of the originating S-CSCF 230 included in the LIA message (S304).

At this time, the I-CSCF 220 transmits a Session Initiation Request (INVITE) message to the originating S-CSCF 230, and if the message is not processed even after a predetermined time is exceeded by the transaction timer, the originating S-CSCF ( It is determined that a failure has occurred in 230, and transmits an LIR message to the HSS 250 to search for another S-CSCF and transmit a call (S305).

The HSS 250 then sends an LIA message to the I-CSCF 220 including an S-CSCF capability list that can select another S-CSCF address or another S-CSCF address in response to the LIR message. It transmits (S306).

The I-CSCF 220 selects a new originating S-CSCF based on the information transmitted from the HSS 250 and transmits a session initiation request (INVITE) message to the selected originating S-CSCF 230 '(S307). .

The originating S-CSCF 230 'may determine that it should operate as the originating S-CSCF based on the "orig" parameter of the top Route header, but the originating S-CSCF 230' is the originating terminal in its registration information. Since (UE # 1) is not registered, it is not possible to determine whether an incoming or outgoing call is made. Therefore, the server assignment request is set by setting the Server-Assignment-Type AVP value to "NO_ASSIGNMENT". Request (hereinafter SAR) message is transmitted to the HSS 250 (S308).

The HSS 250 that stores and manages a plurality of originating S-CSCFs corresponding to a plurality of originating terminals receives the SAR message when the Server-Assignment-Type AVP value is set to "NO_ASSIGNMENT". Since the SAR message is received from the originating S-CSCF 230 'other than the originating S-CSCF 230 corresponding to # 1), it is determined that the originating S-CSCF 230' is recovered. The HSS 250 transmits a SAA message including subscriber profile and recovery information corresponding to the calling terminal UE # 1 to the calling S-CSCF 230 '(S309). In this case, the recovery information may include location information of the calling terminal UE # 1.

Then, the originating S-CSCF 230 ′ transmits a Session Initiation Request (INVITE) message to the I-CSCF 220 (S310), and the I-CSCF 220 sends the incoming S-CSCF 240 and the incoming P−. As the session start request (INVITE) message is transmitted to the called terminal UE # 2 via the CSCF 260 (S311 to S313), a call is connected between the calling terminal UE # 1 and the called terminal UE # 2.

5 is a flowchart illustrating an AS outgoing call processing process in the failure recovery of an originating S-CSCF according to an embodiment of the present invention. Steps S401 to S406 of FIG. 5 are processed in the same manner as steps S301 to S306 shown in FIG. 4, and thus a detailed description thereof will be omitted.

Before performing the LIR message and LIA message exchange with the HSS 250, the I-CSCF 220 transmits a session initiation request (INVITE) message to the assigned originating S-CSCF 230 '. In conjunction with 500, a recovery parameter that can be set in the top Route header can be obtained.

That is, the I-CSCF 220 transmits from the recovery parameter determination apparatus 500 when the session start request (INVITE) message is transmitted to the originating S-CSCF 230 ′ after performing the determination process as shown in FIG. 6. The parameter of the top Route header is set as an "r-orig" parameter and transmitted based on the recovered recovery parameter (S407).

The originating S-CSCF 230 'recognizes that the situation is recovered due to the failure of the existing originating S-CSCF 230 based on the "r-orig" parameter set in the top Route header transmitted from the I-CSCF 220. In step S408, a server-assignment-type AVP value is set to "SCSCF_RESTORATION" to transmit the SAR message to the HSS 250. At this time, in step S408, the originating S-CSCF 230 ′ may set a Server-Assignment-Type AVP value by the method shown in FIG.

That is, if the steps S601 to S607 are performed before the step S408, as a result of the determination of the originating S-CSCF 230 ', the "r-orig" parameter is present in the top Route header, so the originating S-CSCF 230' It is determined that the situation is recovered due to the failure of the S-CSCF 230 to transmit the SAR message set to "SCSCF_RESTORATION" to the HSS 250.

Then, when receiving the SAR message in which the Server-Assignment-Type AVP value is set to "SCSCF_RESTORATION", the HSS 250 transmits the registered S-CSCF 230 corresponding to the originating terminal UE # 1. Recognizing that is a failure situation and transmits a SAA message including the subscriber profile and recovery information corresponding to the originating terminal (UE # 1) to the originating S-CSCF (230 ') (S409). At this time, in step S409, the HSS 250 may process the call by the Server-Assignment-Type AVP value by the method shown in FIG.

That is, when performing the steps S701 to S703 before the step S409, the HSS 250 when the Server-Assignment-Type AVP value transmitted from the originating S-CSCF 230 'is set to "SCSCF_RESTORATION". If the SAA message including the subscriber profile and recovery information corresponding to the calling terminal UE # 1 is transmitted to the calling S-CSCF 230 ', and is not set to "SCSCF_RESTORATION", S110 to S111 shown in FIG. Will perform the steps.

The originating S-CSCF 230 ′ receiving the SAA message transmits a session initiation request (INVITE) message to the I-CSCF 220 (S410), and the I-CSCF 220 receives an incoming S-CSCF 240. And a session start request (INVITE) message to the called terminal UE # 2 via the called P-CSCF 260 (S411 to S413) between the calling terminal UE # 1 and the called terminal UE # 2. The call is connected.

The present invention can also be embodied as computer-readable codes on a computer-readable recording medium. A computer-readable recording medium includes all kinds of recording apparatuses in which data that can be read by a computer system is stored.

Examples of the computer-readable recording medium include a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, and the like. (E.g., transmission over the Internet).

The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. And functional programs, codes, and code segments for implementing the present invention can be easily inferred by programmers skilled in the art to which the present invention pertains.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

110, 160, 200, 201, 260: P-CSCF
120, 140, 140 ', 230, 230', 240, 300: S-CSCF
130, 220, 400: I-CSCF
150, 250, 600: HSS (Home Subscrive Server)
700: subscription locator function
210, 800: Application Server (AS)

Claims (20)

In the incoming call processing method after S (Serving) -Call Session Control Function (CSCF) failure recovery in the Internet protocol Multimedia Subsystem (IMS) network,
I (Interrogating) -CSCF sends a session start request message to the first terminating S-CSCF to which the terminating terminal is registered, and if the response message is not received from the first terminating S-CSCF within a preset time, the first terminating Determining that the S-CSCF is in a fault state;
The I-CSCF performing a location information request (LIR) message and a location information response (LIA) message exchange with an HSS and sending a session initiation request message to an assigned second incoming S-CSCF; And
The second incoming S-CSCF receiving the session initiation request message performs a server assignment request (SAR) message and a server assignment response (SAA) message exchange with the HSS to perform a session initiation request message to the incoming P (Proxy) -CSCF. Incoming call processing method after S-CSCF failure recovery in the IMS network comprising the step of transmitting. 2. The method of claim 1, wherein before the I-CSCF sends a session initiation request message to the second incoming S-CSCF.
Setting, by the recovery parameter determination device interworking with the I-CSCF, a recovery parameter according to a result of determining the route set transmitted from the I-CSCF, and transmitting the recovery parameter to the top Route header of the I-CSCF to the I-CSCF; Include,
The I-CSCF is a method for processing an incoming call after S-CSCF failure recovery in the IMS network for transmitting the session start request message including the top Route header with the recovery parameter set to the second destination S-CSCF. 3. The method of claim 2, prior to setting the recovery parameter in a top Route header of the I-CSCF.
The recovery parameter is defined in the RFC specification, the incoming call processing method after the S-CSCF failure recovery in the IMS network. The method of claim 2, wherein the setting of the recovery parameter in the top Route header of the I-CSCF is
Receiving, by the recovery parameter determining apparatus, the route set from the I-CSCF and determining whether a route header exists, and determining whether an orig parameter exists in a top Route header of the I-CSCF when the route header exists;
Setting a recovery parameter corresponding to an originating service in the top Route header of the I-CSCF when the orig parameter exists in the top Route header of the I-CSCF; And
Setting a recovery parameter corresponding to an incoming service in the top Route header of the I-CSCF when the Route header does not exist or the orig parameter does not exist in the top Route header of the I-CSCF. How to handle incoming calls after a CSCF failover. 5. The method of claim 4, wherein the second incoming S-CSCF is to perform a server assignment request (SAR) message and a server assignment response (SAA) message exchange with the HSS.
The second incoming S-CSCF transmits a server assignment request (SAR) message having a Server-Assignment-Type AVP value set to SCSCF_RESTORATION to the HSS based on the recovery parameter transmitted from the I-CSCF. step; And
The HSS receives the server assignment request (SAR) message and transmits the server assignment response (SAA) message including the subscriber profile and recovery information corresponding to the called terminal to the second called S-CSCF. Method of processing incoming call after S-CSCF failure recovery in IMS network. 6. The method of claim 5, prior to transmitting the server allocation request (SAR) message to the HSS.
The server-assignment-type AVP value is defined in the 3GPP specification, the incoming call processing method after S-CSCF failover in the IMS network. 6. The method of claim 5, wherein the second incoming S-CSCF sends the server assignment request (SAR) message to the HSS.
Determining whether a recovery parameter corresponding to the originating service exists in the top Route header transmitted from the I-CSCF;
Determining whether a recovery parameter corresponding to the incoming service exists in the top Route header when the recovery parameter corresponding to the originating service does not exist in the top Route header;
Transmitting a server assignment request (SAR) message having a Server-Assignment-Type AVP value of NO_ASSIGNMENT to the HSS when a recovery parameter corresponding to the incoming service does not exist in the top Route header; And
When the recovery parameter corresponding to the originating service or the incoming service exists in the top Route header, the server assignment request (SAR) message in which the Server-Assignment-Type AVP value is set to SCSCF_RESTORATION is transmitted to the HSS. Incoming call processing method after the S-CSCF failure recovery in the IMS network comprising a step. 8. The method of claim 7, before the step of the HSS sending the Server Assignment Response (SAA) message to the second incoming S-CSCF.
And determining whether a Server-Assignment-Type (AVP) AVP value transmitted from the second incoming S-CSCF is set to SCSCF_RESTORATION. A computer-readable recording medium storing code for executing an incoming call processing method after S-CSCF failure recovery in an IMS network according to any one of claims 1 to 8. In the outgoing call processing method after S (Serving)-Call Session Control Function (CSCF) failure recovery in the Internet protocol Multimedia Subsystem (IMS) network,
I (Interrogating) -CSCF sends a session start request message to the first originating S-CSCF to which the originating terminal is registered, and if the response message is not received from the first originating S-CSCF within a preset time, the first originating. Determining that the S-CSCF is in a fault state;
The I-CSCF performing a location information request (LIR) message and a location information response (LIA) message exchange with an HSS and sending a session initiation request message to an assigned second originating S-CSCF; And
The second originating S-CSCF receiving the session initiation request message exchanges a server assignment request (SAR) message and a server assignment response (SAA) message with the HSS to transmit a session initiation request message to the I-CSCF. Outgoing call processing method after S-CSCF failover in the IMS network comprising the step. 11. The method of claim 10, wherein before the I-CSCF sends a session initiation request message to the second originating S-CSCF.
Setting, by the recovery parameter determination device interworking with the I-CSCF, a recovery parameter according to a result of determining the route set transmitted from the I-CSCF, and transmitting the recovery parameter to the top Route header of the I-CSCF to the I-CSCF; Include,
The I-CSCF is an outgoing call processing method after S-CSCF failure recovery in an IMS network that transmits the session start request message including a top Route header having the recovery parameter set to the second originating S-CSCF. 12. The method of claim 11, before setting the recovery parameter in a top Route header of the I-CSCF.
The recovery parameter is an outgoing call processing method after S-CSCF failover in an IMS network, characterized in that defined in the RFC specification. The method of claim 11, wherein the setting of the recovery parameter in the top Route header of the I-CSCF
Receiving, by the recovery parameter determining apparatus, the route set from the I-CSCF and determining whether a route header exists, and determining whether an orig parameter exists in a top Route header of the I-CSCF when the route header exists;
Setting a recovery parameter corresponding to an originating service in the top Route header of the I-CSCF when the orig parameter exists in the top Route header of the I-CSCF; And
Setting a recovery parameter corresponding to an incoming service in the top Route header of the I-CSCF when the Route header does not exist or the orig parameter does not exist in the top Route header of the I-CSCF. -Outgoing call handling method after CSCF failover. 15. The method of claim 13, wherein the second originating S-CSCF performs the server assignment request (SAR) message and server assignment response (SAA) message exchange with the HSS.
The second originating S-CSCF transmits a server assignment request (SAR) message to the HSS in which a Server-Assignment-Type AVP value is set to SCSCF_RESTORATION based on the recovery parameter transmitted from the I-CSCF. step; And
The HSS receives the server assignment request (SAR) message and transmits the server assignment response (SAA) message including the subscriber profile and recovery information corresponding to the originating terminal to the second originating S-CSCF. Outgoing call processing method after S-CSCF failover in IMS network. 15. The method of claim 14, prior to transmitting the server assignment request (SAR) message to the HSS.
The Server-Assignment-Type (AVP) AVP value is defined in the 3GPP specification, the outgoing call processing method after S-CSCF failover in the IMS network. 15. The method of claim 14, wherein the second originating S-CSCF sends the server assignment request (SAR) message to the HSS.
Determining whether a recovery parameter corresponding to the originating service exists in the top Route header transmitted from the I-CSCF;
Determining whether a recovery parameter corresponding to the incoming service exists in the top Route header when the recovery parameter corresponding to the originating service does not exist in the top Route header;
Transmitting a server assignment request (SAR) message having a Server-Assignment-Type AVP value of NO_ASSIGNMENT to the HSS when a recovery parameter corresponding to the incoming service does not exist in the top Route header; And
When the recovery parameter corresponding to the originating service or the incoming service exists in the top Route header, the server assignment request (SAR) message in which the Server-Assignment-Type AVP value is set to SCSCF_RESTORATION is transmitted to the HSS. Outgoing call processing method after S-CSCF failover in the IMS network comprising the step of. 17. The method of claim 16, wherein before the HSS sends the Server Assignment Response (SAA) message to the second originating S-CSCF.
And determining whether a Server-Assignment-Type AVP value transmitted from the second originating S-CSCF is set to SCSCF_RESTORATION. A computer-readable recording medium storing code for executing an outgoing call processing method after S-CSCF failure recovery in an IMS network according to any one of claims 10 to 17. In the call incoming and outgoing call processing system after S (Serving) -CSCF (Call Session Control Function) failover in Internet protocol Multimedia Subsystem (IMS) network,
The terminal transmits the session start request message to the registered first S-CSCF, if the response message is not received from the first S-CSCF within a preset time, it is determined that the first S-CSCF is in a failure state, HSS Interrogating (CS-CSCF) for performing a location information request (LIR) message and a location information response (LIA) message exchange with the S-CSCF to transmit a session start request message to the assigned S-CSCF; And
Receive and originate after S-CSCF failover in an IMS network including a second S-CSCF receiving the session initiation request message and performing a server assignment request (SAR) message and a server assignment response (SAA) message exchange with the HSS. Call processing system. 20. The system of claim 19, wherein the incoming and outgoing call processing system is
A recovery parameter determining apparatus for setting a recovery parameter according to a result of determining the route set transmitted from the I-CSCF in the top route header and transmitting the recovery parameter to the I-CSCF;
The I-CSCF is an incoming and outgoing call processing system after S-CSCF failure recovery in an IMS network that transmits the session start request message including the top Route header with the recovery parameter set to the second S-CSCF.

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