KR20110055232A - Method for detecting internet protocol multimedia subsystem deregistration of voice call continuity subscribers - Google Patents

Abstract

PURPOSE: An IMS deregister detection method of a VCC subscriber is provided to manage the IMS registration state of a corresponding subscriber within a VCC AS. CONSTITUTION: A VCC AS(Voice Call Continuity Application Server) performs anchoring for received call processing(S320). An S-CSCF(Serving-Call Session Control Function) transmits call information to a P-CSCF(Proxy-Call Session Control Function)(S350). The P-CSCF transmits call information to a VCC UE(S360). A response message receiving failure event generates in the VCC AS(S370). The VCC AS updates an IMS(Internet protocol Multimedia Subsystem) state of the corresponding subscriber to the deregister state(S380).

Description

Method for detecting Internet protocol Multimedia Subsystem deregistration of Voice Call Continuity subscribers

The present invention relates to Voice Call Continuity (VCC), and in particular, when the VCC subscriber cannot use the IMS without canceling the registration in the IP Multimedia Subsystem (IMS), the subscriber can manage the unregistered state of the IMS of the subscriber. So that It relates to a method of detecting the cancellation of IMS registration of VCC subscribers.

IMS Service Continuity is a technology that provides data continuity so that users are not disconnected from other networks and devices while they are on the move. As the network has evolved from a Circuit Switched (CS) network to a Packet Switched (PS) network, many discussions have been made about technical standards for continuously providing voice call service provided by the existing network in the PS network. come. Recently, with the introduction of IPTV (Interner Protocol Television), mobile TV, and triple-play services as well as voice services, a market demand for providing continuity of real-time data and multimedia services has arisen. To enable this, 3GPP (3rd In the Generation Partnership Project, standardization is being progressed not only for delivering multimedia sessions between different networks to the same terminal device but also for transferring sessions between different devices in the same network.

Service continuity can be broadly classified into network transfer and device transfer. Among these, network delivery is a technology for delivering a session without disconnection between different networks within the same terminal device. A typical standard technology for network delivery may include a VCC (Voice Call Continuity) technology.

VCC is a technology that provides continuity of voice call service when the terminal moves between the existing CS network and the IMS network. Session delivery control in VCC is performed by the VCC application server (VCC AS), which performs seamless handover between heterogeneous networks such as Wi-Fi (WiFi) or Global System for Mobile communication (GSM), It provides a seamless voice service function to a VCC subscriber using a DBB (DualBand DualMode) terminal even under limited coverage.

The VCC AS located in the IP Multimedia Subsystem (IMS) is disconnected by allowing all the voice call setup related signaling of the VCC subscribers to pass through them, and controlling the call through anchoring. Can provide voice service that is not available.

If an attempt is made to reach a VCC subscriber, the VCC AS will allow the call to be forwarded according to the subscriber's IMS / CS registration status. Therefore, when the VCC subscriber changes the IMS / CS registration status, the VCC AS receives a corresponding information.

According to the proposal of the conventional GSM technology, when the VCC subscriber is not able to use the IMS without registering with the IMS, the VCC UE determines that the IMS is not available and transmits an SMS message to the VCC AS so that the VCC AS receives the VCC. Manage by changing the subscriber's IMS registration status. In other words, if the VCC subscriber cannot use the IMS without registering with the IMS, a message must be received from the subscriber to cancel the registration of the subscriber and the active subscriber state management of the system cannot be expected. There is this.

Therefore, the technical problem to be achieved by the present invention is the VCC subscriber's IMS that can manage the registration status information by detecting the cancellation of registration of the subscriber when the VCC subscriber is not able to use the IMS without the registration to the IMS It is to provide a method for detecting registration termination.

In accordance with an aspect of the present invention, a method for detecting cancellation of an IMS registration of a VCC subscriber, in a system for providing a VCC (Voice Call Continuity) service between heterogeneous networks, may proceed to an Internet Protocol Multimedia Subsystem (IMS). When the incoming call occurs, the VCC AS sends an invitation message to a Call Session Control Function (CSCF) and waits for a response message from the called VCC UE; Generating a response message reception failure event if the VCC AS does not receive a response message from the VCC UE within a preset time; And managing, by the VCC AS, an IMS state of a corresponding subscriber to a deregistration state according to the response message reception failure event.

According to an embodiment of the present invention, a method for detecting cancellation of IMS registration of a VCC subscriber, in a system for providing a VCC service between heterogeneous networks, requesting an incoming call for a specific VCC UE from a CSCF to a VCC AS. When the invitation message (INVITE) is received, the VCC AS anchoring for incoming call processing; The VCC AS determines that the incoming call to proceed to the IMS and sends an invitation message to the CSCF; Determining, by the VCC AS, whether a response message from the VCC UE is received for the transmitted invitation message within a preset time; And if the response message is received within a preset time according to the determination result, proceeds with the IMS connection, and if the response message is not received within the preset time, updating and managing the subscriber's IMS state to the registered state. It may include.

Preferably, the VCC AS determines that the incoming call proceeds to IMS, sends an invitation message to the S-CSCF of the CSCF, and when the S-CSCF transmits call information to the P-CSCF, the P-CSCF The call information is transmitted to the VCC UE and waits for reception of a response message.

Preferably, the response message is a 180 RINGING response message from the VCC UE, the failure message reception failure event is 180 Ringing Timeout.

According to an embodiment of the present invention, if a response to a call attempted by the IMS is not received while the incoming call processing flowed into the VCC AS is not received, the VCC AS manages the subscriber's IMS registration status in a registered state, thereby allowing the VCC subscriber to receive the VCC AS. It is effective to more actively manage the registration status of. In addition, it is possible to prevent unnecessary waste of radio resources for fuzzy state detection for the subscriber.

In order to fully understand the present invention, the operational advantages of the present invention, and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings which illustrate preferred embodiments of the present invention and the contents described in the accompanying drawings. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals in the drawings denote like elements.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. As used herein, “comprises” and / or “comprising” refers to the presence of one or more other components, steps, operations and / or elements. Or does not exclude additions.

1 is a configuration diagram showing a schematic configuration of a VCC network to which the present invention is applied.

As shown in FIG. 1, the VCC network 1000 may include an IMS Core Network (IP Multimedia Subsystem Core Network) 100, a Wi-Fi Network 200, and a CS (Circuit Switched) Network 300. Can be.

The VCC UE (User Equipment, for example, DBDM terminal) 400 used by the VCC subscriber is a terminal capable of VCC service, performs handover between the Wi-Fi network 200 and the CS network 300 and provides a seamless service. I can receive it.

The IMS core network 100 includes a VCC application server (AS) 110, a call session control function (CSCF) 120, a signaling gateway or SGW (130), a media gateway (MGW) 140, Media Gateway Control function (MGCF) 150, and Home Subscriber Server (HSS) 160.

The VCC AS 110 is an application server that provides a VCC service, and establishes a voice call to the VCC UE 400 and between the CS domain (or CS network) and the IMS domain (or IMS network). It is composed of entities that perform a series of functions for switching the connection path of the < RTI ID = 0.0 >

2A is a functional block diagram illustrating an example of a configuration of the VCC AS 110 illustrated in FIG. 1. Referring to this, the VCC AS 110 includes a domain transfer function (111), a domain selection function (112), a DSF (CS adaptation function) 113, and a CAMEL service unit CAMEL Svc 114. The DTF 111 performs domain transfer between the CS domain and the IMS domain. The DSF 112 is responsible for determining (selecting) which domain to use to forward an incoming call to the VCC UE 400. That is, the DSF 112 determines whether to select a CS domain or an IMS domain according to the operator policy and / or user preferences. To this end, the DSF 112 may refer to the IMS registration status and the CS registration status. The CSAF 113 may perform a function necessary for registration with the CS domain. For example, the CSAF 113 may serve as a proxy of the VCC UE 400. The CAMEL service unit 114 allocates an IMRN (IP Multimedia Routing Number) for routing the CS call to the IMS.

The CSCF 120 is an entity in charge of a part related to call and session processing, and includes a gateway function for an incoming call, a call control function, a SPD (Serving Profile Database) function, an address processing function, and the like. The gateway function for incoming calls refers to acting as an entry point and performing routing for incoming calls. In addition, it performs service triggering (triggering) for the input call and is responsible for communication with the HSS (160).

2B is a configuration diagram illustrating a schematic configuration of the CSCF 120. As shown in FIG. 2B, the CSCF 120 may include a P (Proxy) -CSCF 122, an Interrogating (CSCF) 124, and a Serving-CSCF 126. The P-CSCF 122 serves as a proxy or user agent as a point where UEs including the VCC UE 400 first meet to access the IMS core network 100. And transmits a SIP request and a SIP response to the VCC AS 110. The I-CSCF 124 provides a connection to the Subscriber Location Function (SLF) (not shown) and the HSS 160 as a proxy at the edge of the management domain, and sends SIP requests to the appropriate S-CSCF. It acts as Topology Hiding Inter-network Gateway (THIG). The S-CSCF 126 is a proxy that plays a key role in the signal plane. When the user connects, the S-CSCF 126 stores a user location, filters a SIP message, or grants access to the HSS 160.

The SG 130 performs a function of converting a transport layer of a signaling protocol to handle the interconnection of signals between the CS domain and the IMS domain.

The MGW 140 is responsible for media data conversion such as voice and video between the CS domain and the IMS domain.

The MGCF 150 is a network entity that allows an IMS user and a CS user to communicate with each other and is responsible for signaling conversion for interworking between the IMS core network 100 and the CS network 300 (or PSTN) that is an existing network. do. Although not shown, the MGCF 150 may include a BGCF (Breakout Gateway Control Function). The BGCF is optimal through number translation for calls received from the IMS core network 100 to the CS network 200. Select the incoming network.

The HSS 160 performs user mobility management between heterogeneous networks and generates security information of a subscriber. The HSS 160 generates data for user authentication, message integrity check, and encryption function support, and supports each service function element authentication procedure. In addition, it checks whether the mobile subscriber can roam and performs network access authority verification function.

The Wi-Fi network 200 may include a Radio Access Network (RAN) 210 and a Connectivity Access Network (IP-CAN) 220.

The RAN 210 is an infrastructure for providing high-speed Internet access and mobile communication service of a mobile device including the VCC UE 400, and performs functions such as access to a PTSN and the Internet, roaming, and quality of service.

The IP-CAN 220 is a network for packet data transmission to the VCC UE 400. In order for the VCC UE 400 to access an IMS domain and receive a service, the IP-CAN 220 must go through the IP-CAN.

The CS network 300 includes a Service Control Point (SCP) 310, a Home Location Register (HLR) 320, a Short Message Service Center (SMSC) 330, an SS7 Signal Transfer Point (STP) 340, and an MSC. (Mobile Switching Center) 350, Base Station Controller (BSC) 360, and Base Transceiver Station (BTS) 370.

The SCP 310 is a computer capable of online access with a centralized database supporting various functions, and provides service logic for various services and performs an intelligent network service scenario.

The HLR 320 is a system for storing and managing information of a subscriber and location information of a terminal in real time, and provides current location information of a subscriber terminal for call reception.

The SMSC 330 provides a function of storing and transmitting a short message in which a message to be transmitted does not exceed 80 bytes.

The SS7 STP 340 serves as a path of the SS7 protocol and switches various SS7 messages to the destination point.

The MSC 350 is responsible for mobility management, location registration / management, authentication, handover, roaming, and the like.

The BSC 360 manages and controls a plurality of base stations (BTSs) and interworks with the MSC 350.

The BTS 370 is connected to a mobile device including the VCC UE 400 in a wireless section to control the mobile device and connect a call channel.

In the VCC network configured as described above, in the present invention, when the use of the IMS network becomes impossible without performing a de-registration procedure for the IMS network of the VCC subscriber, the VCC AS 110 is a VCC AS 110. The IMS registration status can be managed as the IMS registration canceled status by not receiving a response message for a call attempted by the IMS during the incoming call processing.

In addition, the VCC AS 110 does not make a call request using the IMS when the call to the VCC subscriber.

3 is a flowchart illustrating a procedure of a method for detecting cancellation of IMS registration of a VCC subscriber according to an embodiment of the present invention.

Referring to FIG. 3, when an invitation message (INVITE) requesting an incoming call for the VCC UE 400 is received from the S-CSCF 126 of the CSCF 120 to the VCC AS 110 in step S310, In step S320, the VCC AS 110 performs an anchoring for incoming call processing. Anchoring means storing information for the domain switching control of the call in the VCC AS 110 in order to prepare for a case where a call is domain switched, that is, to support a VCC service for the call. do. When anchoring is performed, control signaling for the VCC service always passes through the VCC AS 110.

In addition, the VCC AS 110 selects a domain to which an incoming call will be made. Here, it is assumed that the VMS AS 110 proceeds to IMS. More specifically, the DSF 112 of the VCC AS 110 determines whether to select a CS domain or an IMS domain according to the operator policy and / or user preferences. In this embodiment, it is assumed that the IMS domain is selected.

The VCC AS 110 determines (or determines) that the incoming call proceeds to IMS in step S330, and transmits an invitation message to the S-CSCF 126 to proceed with the incoming call in step S340, and VCC UE 400. Wait for a response message (180 RINGING response message) from When the VCC AS 110 transmits the invitation message to the S-CSCF 126, the timer may be set to a predetermined time to check whether the 180 RINGING response message is received within a predetermined time.

The S-CSCF 126 receiving the invitation message transmits call information by sending an invitation message to the P-CSCF 122 in step S350.

Upon receiving the call information, the P-CSCF 122 transmits call information to a VCC subscriber, that is, the VCC UE 400 in step S360, and waits for a response message from the VCC UE 400.

If the VCC UE 400 receiving the invitation message from the P-CSCF 122 sends a 180 RINGING response message from the P-CSCF 122 in response to the invitation message, the 180 RINGING response message is sent to the S-CSCF 126. It is transmitted to the VCC AS 110 via. Accordingly, when the VCC AS 110 receives the 180 RINGING response message from the VCC UE 400 within a preset time, the VCC AS 110 proceeds with the IMS connection.

However, when the VCC UE 400 is already registered and fails to respond to the invitation message from the P-CSCF 122, the VCC AS 110 may send a 180 RINGING response message from the VCC UE 400 within a preset time. Does not receive Accordingly, a response message reception failure event 180 ringing timeout occurs in the VCC AS 110 that does not receive a 180 RINGING response message from the VCC UE 400 within a predetermined time from the VCC subscriber in step S370.

Accordingly, in step S380, the VCC AS 110 updates and manages the IMS state of the subscriber to the registered termination state.

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

Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage device, and the like. The program code for performing the online advertising method according to the present invention may be a carrier wave ( For example, transmission via 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 in the art to which the present invention belongs.

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

BRIEF DESCRIPTION OF THE DRAWINGS In order to better understand the drawings cited in the detailed description of the invention, a brief description of each drawing is provided.

1 is a configuration diagram showing a schematic configuration of a VCC network to which the present invention is applied.

FIG. 2A is a functional block diagram illustrating an example of a configuration of the VCC AS illustrated in FIG. 1.

2B is a diagram illustrating a schematic configuration of a call session control function (CSCF).

3 is a flowchart illustrating a procedure of a method for detecting cancellation of IMS registration of a VCC subscriber according to an embodiment of the present invention.

Claims (10)

In the system for providing VCC (Voice Call Continuity) service between heterogeneous networks, When an incoming call to proceed to the Internet protocol Multimedia Subsystem (IMS) occurs, an application server (VCC AS) transmitting an invitation message to a call session control function (CSCF) and waiting to receive a response message; Generating a response message reception failure event if the VCC AS does not receive a response message from a VCC user equipment (UE) within a preset time; And And updating and managing, by the VCC AS, an IMS state of the subscriber to a deregistration state according to the response message reception failure event. The method of claim 1, further comprising the step of waiting for the response message to be received. Receiving an invitation message (INVITE) requesting an incoming call for the VCC user equipment (UE) from the CSCF to the VCC AS; Anchoring the VCC AS for an incoming call process; And The VCC AS further comprises the step of determining the incoming call to the IMS IMS registration cancellation method of the VCC subscriber. The method of claim 2, wherein the waiting for receiving the response message is Determining, by the VCC AS, to forward the incoming call to the IMS and sending an invitation message to S (Serving) -CSCF of the CSCF; The S-CSCF transmitting call information to P (Proxy) -CSCF; And And transmitting, by the P-CSCF, the call information to the VCC UE and waiting to receive a response message from the VCC UE. The method of claim 3, wherein the response message 180 RINGING response message VCC subscriber IMS registration cancellation detection method. The method of claim 4, wherein the response message reception failure event A method of detecting the cancellation of IMS registration of a VCC subscriber having a 180 ringing timeout. In the system for providing heterogeneous VCC service, When an invitation message (INVITE) is received from a CSCF requesting an incoming call for a specific VCC UE to the VCC AS, annealing the VCC AS to process an incoming call; Determining, by the VCC AS, to forward the incoming call to IMS and sending an invitation message to the CSCF; Determining, by the VCC AS, whether a response message is received from the specific VCC UE for the transmitted invitation message within a preset time; And If the response message is received within a preset time according to the determination result, proceeding with the IMS connection, and if the response message is not received within the preset time, updating and managing the subscriber's IMS status to the registered state; Method of detecting cancellation of IMS registration of a VCC subscriber. The method of claim 6, wherein the invitation message sending step Determining, by the VCC AS, to forward the incoming call to the IMS and sending an invitation message to the S-CSCF of the CSCF; The S-CSCF transmitting call information to a P-CSCF; And And transmitting, by the P-CSCF, the call information to the VCC UE and waiting to receive a response message from the specific VCC UE. 8. The method of claim 7, wherein the response message is 180 RINGING response message VCC subscriber IMS registration cancellation detection method. The method of claim 8, wherein the response message reception failure event is A method of detecting the cancellation of IMS registration of a VCC subscriber having a 180 ringing timeout. A recording medium on which a computer program for executing the IMS registration cancellation detection method according to any one of claims 1 to 9 is recorded.

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