KR20050017319A - Mbms dedicated signalling bearer management method over iur interface for serving multimedia broadcast/multicast service in mobile communication system in radio network controller - Google Patents

Abstract

PURPOSE: A method for managing a dedicated signaling bearer to supply a broadcast service in a mobile communication system is provided to generate dedicated Iur signaling connections assigned to each MBMS, and to manage the generated signaling connections, thereby effectively exchanging an MBMS control message between RNCs(Radio Network Controllers). CONSTITUTION: The first dedicated Iur signaling bearer(510) is generated for UEs for setting the first RNC to an SRNC(Serving RNC) while setting the second RNC to a DRNC(Controlling RNC) among UEs receiving a specific MBMS. Among the UEs, the second dedicated Iur signaling bearer(520) is generated for UEs for setting the first RNC to a DRNC while setting the second RNC to an SRNC. The first RNC and the second RNC transmit an RNSAP(Radio Network Subsystem Application Part) message by using a proper one of the Iur signaling bearers(510,520), depending on whether a subject for generating the RNSAP message is the SRNC or the DRNC(CRNC).

Description

Dedicated signaling bearer management method for providing broadcasting service in mobile communication system

The present invention relates to a multicast multimedia broadcasting service (hereinafter referred to as an 'MBMS'), and more particularly, to provide a method for a base station controller to manage an Iur signaling connection dedicated to an MBMS service for providing the MBMS. .

Recently, due to the development of the telecommunications industry, a packet service that transmits not only voice service data but also large data such as packet data and circuit data is being changed, that is, a service for multicasting multimedia communication. Accordingly, in order to support the multicasting multimedia communication, a broadcast / multicast service providing a service to a plurality of mobile terminals (hereinafter referred to as UEs) from one or several multimedia data sources. ) Is being discussed. The broadcasting / multi-broadcasting service is a multimedia broadcasting / multi-broadcasting service supporting a multimedia service such as a cell broadcast service (hereinafter, referred to as a “CBS service”), a message-oriented service, and real-time video, audio, still images, and text. (Multimedia Broadcast / Multicast Service, hereinafter referred to as "MBMS Service").

The CBS service is a service that broadcasts a plurality of messages to all UEs located in a specific service area. In this case, the specific service area for providing the CBS service may be an entire area for providing the CBS service in one cell.

The MBMS service is a service that simultaneously supports multimedia formats such as real time video, voice, still image, and text, and requires a large amount of transmission resources. Therefore, the MBMS service is serviced through a broadcast channel in that there is a possibility that a large number of services can be simultaneously deployed in one cell. In particular, the MBMS service requires more radio resources than the CBS service. The MBMS service is a "point to point (hereinafter referred to as" PtP "mode) mode" in consideration of the number of UEs to be provided with the MBMS service in one cell or the transmission power used by the MBMS service. And "Point to Multi-point (hereinafter referred to as" PtM ") mode" mode. The PtP mode provides a desired MBMS service by allocating a dedicated channel for each UE when the number of UEs that desire MBMS service in a cell or when there is sufficient surplus transmission power. The PtM mode is a method of providing a desired MBMS service by allocating a common channel to UEs when the number of UEs that desire MBMS service in a cell or when there is insufficient surplus transmission power. Of course, it is also possible to switch the MBMS service provided by the PtP mode for each cell to PtM mode or to provide the MBMS service provided in the PtM mode by switching to PtP mode. However, the mode switching is limited to the case where the environment for providing the MBMS service changes in terms of efficient use of radio resources.

Next, a network structure for providing the MBMS service in the mobile communication system will be described with reference to FIG. 1.

1 is a diagram schematically illustrating a network structure for providing an MBMS service in a mobile communication system.

Referring to FIG. 1, a multicast / broadcast-service center (MB-SC) hereinafter referred to as a "MB-SC" 110 is a source for providing an MBMS stream. (source). The MB-SC 110 schedules a stream for the MBMS service and transmits the stream to the transmission network 120. The transmission network 120 is a network existing between the MB-SC 110 and a service packet radio service support node (Serving 'GPRS (General Packet Radio Service) Support Node' (hereinafter referred to as "SGSN") 130). (network), and serves as a communication path for delivering the stream for the MBMS service received from the MB-SC (110) to the SGSN (130). Although not shown, the transmission network 120 may be connected to an external network through a Gateway GPRS Support Node (hereinafter referred to as a "GGSN"). The SGSN 130 receiving the stream for the MBMS service in the transmission network 120 controls the MBMS-related services of subscribers, that is, UEs, to receive the MBMS service. For example, the service manager manages MBMS service charging related data of each subscriber and selectively transmits MBMS data to a specific Radio Network Controller (hereinafter, referred to as "RNC") 140. To this end, the SGSN 130 needs to know the list of the specific RNCs receiving the MBMS service. The RNC 140 refers to an apparatus for controlling the plurality of cells 160 and 170. The RNC 140 transmits MBMS data to a cell where a UE requesting MBMS service exists among cells managed by the RNC 140, and controls a radio channel configured to transmit the MBMS data. In addition, it manages the information about the MBMS service by the stream for the MBMS service received from the SGSN (130). As described above, the RNC 140 must know the list of cells receiving the MBMS service in order to transmit selective MBMS data to the corresponding cells. Cell 1 (Cell 1) 160 and Cell 2 (Cell 2) 170 refer to a base station apparatus for transmitting MBMS-related data to subscribers. Typically, a base station may have a plurality of cells, but for convenience of description, it is assumed that one base station is composed of one cell. In the cells 160 and 170, a plurality of UEs that wish to receive the MBMS service may be located at any time. In FIG. 1, UE # 1 161, UE # 2 162, and UE # 3 163 are located at a first base station (cell 1) 160, and a UE is located at a second base station (cell 2) 170. An example of # 4 171 and UE # 5 172 is located. The UEs 161, 162, 163, 171, and 172 refer to terminal devices or subscribers that want to receive MBMS service from the RNC 140 through cell 1 160 or cell 2 170. Although not shown in FIG. 1, a Home Location Register (HLR) is connected to the SGSN 130 to perform subscriber authentication for an MBMS service.

1 illustrates a structure in which only one RNC 140 is connected to one SGSN 130 and the SGSN 130 in response to one MBMS service. However, it will be apparent that there may be a plurality of SGSNs corresponding to one MBMS service, and there may be a plurality of RNCs for each SGSN.

2 is a diagram illustrating a signal flow for providing an MBMS service between a UE and a network in a mobile communication system.

Referring to FIG. 2, the UE performs a SUBSCRIPTION process with a core network (CN) to receive a random MBMS service (step 201). Here, the core network includes an MB-SC, a transmission network, and an SGSN as described in FIG. 1. The user registration process is a process of exchanging basic information related to charging or receiving MBMS service in an MBMS service between a service provider and a user. When the user registration is completed, the core network performs an ANNOUNCEMENT process to guide basic information on MBMS services currently available, for example, menu information, to UEs serving the MBMS service. Perform (step 202). Here, the menu information is information indicating time information (START TIME) and duration time for each MBMS service. The core network may broadcast the menu information through predetermined service areas (broadcast service such as CBS) or transmit only to UEs having a MBMS service request. The core network transmits an MBMS service ID for identifying each MBMS service to the UE through the menu information. Here, the MBMS service identifier may be composed of a multicast address (hereinafter referred to as a "multicast IP address") and an access point name (hereinafter referred to as "APN").

Each of the UEs notified of the menu information through the service guide process selects a specific MBMS service to be serviced from the menu information, and performs a service request (JOINING) process for the selected MBMS service to the core network. Step 203). Here, the service request message transmitted by the UE to the core network includes an MBMS service identifier indicating the selected MBMS service and a UE identifier indicating the corresponding UE. According to the service request of the UE, the core network identifies the MBMS service that the UE wants to receive. In this process, the SGSN, the transmission network, etc. constituting the core network may recognize UEs that want to receive a certain MBMS service and a device where the UEs are located. That is, through the JOINNING process, SGSN can grasp the list of UEs and the list of RNCs where the UEs are located, thereby creating an MBMS context for managing the MBMS service.

Thereafter, the core network performs a NOTIFICATION process, which is a kind of paging process indicating that an MBMS service requested by the UE will be started (step 204). In the calling process performed in step 204, an existing calling method may be used or an calling method optimized for MBMS service published in application number P2002-34704 previously filed by the same applicant may be used. Meanwhile, the quality of service (hereinafter referred to as "QoS") information and the multicast region information of the MBMS service are transmitted through the service notification process.

Upon detecting that the requested MBMS service will be started soon through the service notification process, the UE actually allocates radio resources for providing the MBMS service through the RADIO RESOURCE ALLOCATION process (step 205). . Then, the radio resource related information is announced to related devices. Here, the radio resource allocation process, the RNC informs the UEs located in any cell radio bearer information to be transmitted the MBMS service in the cell (hereinafter referred to as "radio bearer setup") &Quot; Step " and the RNC informs transport bearer information and radio bearer information to be configured on the Iub interface to cells where UEs to receive MBMS service are located (hereinafter, " radio link setup " ) "Step). In the RESOURCE ALLOCATION process, the RNC is based on information about the number of UEs belonging to an arbitrary cell and a radio resource management function (PtM) / point-to-point (PtM). / PCE can be determined.

When the radio resource allocation process is completed, all UEs that want to receive a specific MBMS service are aware of radio link related information to be provided with the specific MBMS service and higher layer information to be processed. In addition, the cells to which the UE belongs to complete the radio link and Iub interface configuration. With the preparation for providing the MBMS service between the RNC and the UEs as described above, the core network performs an MBMS data transmission process of transmitting MBMS service data to the UEs through the RNC (step 207). In addition, in the DATA TRANSFER step, a ciphering key may be updated. For example, if a need arises to change the ciphering key for a given MBMS service, the RNC delivers a new ciphering key to all UEs receiving the MBMS service.

Thereafter, when the MBMS service data transmission is completed, a radio resource release process of releasing the set radio resources, that is, the transport bearer and the radio bearer, is performed between the UE and the core network (step 207). The devices configuring the core network delete relevant information of the MBMS service of which the radio resource is released. Otherwise, the UE may voluntarily request to stop receiving a service through a service deleting process in the middle of receiving any MBMS service.

Typically the UE has mobility. Accordingly, the UE may move to a service area by another RNC while establishing an RRC connection to a specific RNC and receiving MBMS service through the specific RNC. In this case, the specific RNC registered by the UE to receive the MBMS service for the first time is called a 'Serving RNC (hereinafter referred to as a' SRNC '), and the RNC currently receiving the MBMS service by moving is referred to as a' drift RNC '. (Drift RNC, hereinafter referred to as "DRNC"). The DRNC and the Control RNC (hereinafter referred to as "CRNC") are distinguished by the control target (UE or base station) but indicate the same RNC.

Meanwhile, signaling between the SRNC and the DRNC should be provided in order to continuously provide an MBMS service to a UE whose SRNC and the DRNC do not match. For this purpose, there is typically an Iur interface between RNCs and a signaling connection control part (hereinafter referred to as "SCCP") signaling connection is used as a signaling bearer on the Iur interface. The RNSAP (Radio Network Subsystem Application Part) message between the two RNCs is transmitted through the SCCP signaling connection.

As described above, the RNC has an SCCP layer and an RNSAP layer to transmit a Radio Network Subsystem Application Part (RNSAP) message.

The SCCP layer provides the following two transport services to the RNSAP layer.

(1) Connection Oriented Data Transfer Service: A message is transmitted by using a signaling connection allocated exclusively for each UE or RNC. In this case, a procedure for creating and releasing an SCCP signaling connection is additionally needed. The signaling message using the connection-oriented signaling connection then does not include a UE identifier or an RNC identifier.

(2) Connectionless data transmission service: There is no signaling connection allocated exclusively for each UE or RNC, and a signaling message using the connectionless signaling connection must include a UE identifier or an RNC identifier.

The RNSAP layer is a protocol for providing signaling information through an Iur interface. The procedures constituting the RNSAP unit can be divided into four categories as follows.

(1) RNSAP Basic Mobility Procedures

RRC transmitted through Common Control Channel (CCCH) as a procedure to support mobility in UTRAN for UEs located under DRNS but not yet allocated a Radio Link (RL) via DRNS. Contains procedures for carrying messages and paging messages over the Iur interface.

(2) DCH Procedures

Dedicated CHannel (DCH), Down-link Shared CHannel (DSCH), and High-Speed Downlink Shared Channel (HS-DSCH) between two RNSs for UEs located under DRNS and assigned RL through DRNS As a procedure for managing Speed-Downlink Shared CHannel, a signaling bearer allocated exclusively to a specific UE is used. It includes procedures for setting up, adding, and deleting RLs, procedures used to synchronize RLs, procedures for resetting RLs or physical channels, and procedures for performing dedicated measurements.

(3) RNSAP Common Transport Channel Procedures

As a procedure for managing a common transport channel on an Iur interface, the UE includes a procedure for allocating / releasing resources of a common transport channel between SRNS and DRNS when a UE uses a common transport channel under DRNS.

(4) RNSAP Global Procedures

For the overall management of the RNC not related to one specific UE, Common Measurement, procedures for notifying that there is an error in a message received through the Iur interface and resetting in case of an error that cannot be recovered are included.

3 is a diagram illustrating a procedure of creating a SCCP signaling connection for using a conventional connection-oriented SCCP data transmission service, and illustrates a process of establishing a signaling connection between a first RNC and a second RNC for one UE. Here, the first RNC and the second RNC serve as SRNC and DRNC for one UE which has established an RRC connection.

Referring to FIG. 3, in step 301, the SRNC 310 starts to establish SCCP connection when it is necessary to request the DRNC 320 to allocate a dedicated resource such as a DCH for a specific UE. In step 302, the RNSAP layer 311 of the SRNC 310 constructs an RNSAP message to be transmitted to the DRNC 320 and transmits the RNSAP message to the SCCP layer 312. According to an embodiment, when requesting to configure the RL with the DRNC 320, the RNSAP layer 311 transmits a RADIO LINK SETUP REQUEST message to the SCCP layer 312.

Correspondingly, the SCCP layer 312 configures a SCCP message called a Connection Request (CR) message as follows.

CR = [LR_SRNC, RNSAP Message]

The CR message is a message transmitted by the SCCP layer 312 to initially establish an SCCP connection. In the CR message, LR_SRNC (Local Reference_SRNC) is a temporary identifier assigned by the SCCP layer 312 to the SCCP connection. The LR_SRNC is used to identify the SCCP connection when the SCCP layer 322 of the DRNC 320 transmits an SCCP message after the SCCP connection is established. The SCCP layer 312 transmits the CR message to the SCCP layer 322 of the DRNC 320 in step 303.

When the SCCP layer 322 of the DRNC 320 receives the CR message, the DRNC 320 sends an RNSAP message (RADIO LINK SETUP REQUEST message) included in a payload portion of the CR message in step 304. Transfer to the RNSAP layer 321 of. The SCCP layer 322 allocates LR_DRNC for the SCCP connection. The LR_DRNC is a temporary identifier for an SCCP connection to be set up through a CR message. The LR_DRNC is used by the SCCP layer 312 of the SRNC 310 to identify the SCCP connection in transmitting an SCCP message after the SCCP connection is established.

The RNSAP layer 321 receives and processes the RADIO LINK SETUP REQUEST message, and transmits a RADIO LINK SETUP RESPONSE message in response to the RADIO LINK SETUP REQUEST message to the SCCP layer 322 in step 305. When the SCCP layer 322 receives the RADIO LINK SETUP RESPONSE message, the SCCP layer 322 configures an SCCP message called a Connection Confirm (hereinafter referred to as "CC") message using the LR_DRNC determined above.

CC = [LR_DRNC, LR_SRNC, RNSAP message]

The CC message is a response message sent by the SCCP layer 322 that received the CR message to the SCCP layer 312 that transmitted the CR message in establishing an arbitrary SCCP connection.

The SCCP layer 312 of the SRNC 310 that receives the CC message stores the LR_DRNC received through the CC message, and transmits the RNSAP message included in the CC message to the RANAP layer 311 in step 307. do.

Through the above-described process, the SCCP layers 312 and 322 which newly establish the SCCP connection exchange the CR message and the CC message, thereby recognizing the temporary identifiers LR_SRNC and LR_DRNC allocated by the counterpart to the SCCP connection. As described above, the SRNC 310 and the DRNC 320 share [LR_SRNC, LR_DRNC] with respect to any SCCP connection. Thereafter, when the SRNC 310 intends to transmit the RNSAP message through the SCCP connection, the SRNC 310 constructs a SCCP message including the stored LR_SRNC and LR_DRNC and delivers the same to the DRNC 320. The DRNC 320 identifies the SCCP connection by the LR_SRNC and the LR_DRNC received through the SCCP message, and processes the RNSAP message included in the SCCP message for the UE corresponding to the SCCP connection.

Considering a case where a SRNC to which an UE establishes an RRC connection due to mobility and a CRNC managing a cell in which a UE is currently located are different from each other in a typical mobile communication system (the SRNC and another CRNC are referred to as a Drift RNC). In the case of a system that does not support the MBMS service, data is delivered to the SRNC through the Iu interface in the core network, and is transferred from the SRNC to the DRNC via the Iur interface. The DRNC transmits data received through the Iur interface to the UE through a cell.

In contrast, in the case of a system supporting the MBMS service, data is directly transmitted to the CRNC through the Iu interface in the core network. The CRNC does not need to transmit data through the Iur interface by transmitting data received through the Iu interface to the UE through a cell.

The mobility of the UE subscribed to the MBMS can be equally supported by the existing standard according to the four RRC states. However, in the existing standard, when a UE moves to a DRNC for each UE, it creates an UE context in the DRNC and supports signaling connection on an Iur interface for each UE, which is inefficient for managing a plurality of UEs belonging to one service group. That is, conventionally signaling for MBMS service on Iur interface, which is required to create MBMS service context for multiple UEs belonging to one service group to DRNC, process DRMS operation for MBMS, and deliver the result to SRNC. Connection is not supported.

Conventionally, in order to support this, the MBMS service identifier is transmitted in an RNSAP message every time using a connectionless SCCP connection, or as many UEs want to receive MBMS for the same MBMS service using the connection-oriented SCCP connection generated for each UE. The same message must be repeated on the Iur interface.

Accordingly, an object of the present invention for solving the above problems is to provide a method for creating and managing a dedicated Iur signaling connection allocated for each MBMS service to exchange MBMS control messages between RNCs more efficiently.

Another object of the present invention is to provide a method for efficiently transmitting MBMS service related information and mobile terminal related information in which an MBMS service request is made between different RNCs in a mobile communication system.

Another object of the present invention is to provide a method for defining and managing a dedicated signaling connection for each MBMS service between two RNCs so as to exchange an RNSAP message for controlling an MBMS service.

Another object of the present invention is to provide a method of exchanging RNSAP messages using dedicated signaling connections for each MBMS service for synchronization and information exchange between MBMS service contexts between two RNCs in which an MBMS service context exists.

In a first aspect for achieving the above object, in the present invention, in creating an Iur signaling bearer dedicated to MBMS service, after a session starts, one RNC performs an MBMS UE Attach procedure with a counterpart RNC for the first time. A service dedicated Iur signaling bearer is generated.

In the first aspect, preferably in defining a dedicated signaling connection for each MBMS service between two RNCs so that RNSAP messages for controlling MBMS services can be exchanged between RNCs, a dedicated Iur signaling bearer for one MBMS service. In providing a method for generating an Iur signaling bearer used to transmit an MBMS-related RNSAP control message when a subject generating and transmitting an MBMS-related RNSAP control message in one RNC is an SRNC, and an MBMS-related RNSAP control message When the subject generating and transmitting the CRNC is a DRNC, the Iur signaling bearer used to transmit the MBMS-related RNSAP control message is separated and used.

In the first aspect, preferably in using the MBMS service dedicated Iur signaling bearer, after the session is started, after the MBMS service dedicated Iur signaling bearer is created, when exchanging the MBMS-related RNSAP control message between the two RNCs The RNSAP message is exchanged using the generated IMS signaling bearer dedicated to the MBMS service, and is differently allocated to each other depending on whether the subject transmitting the MBMS-related RNSAP control message is SRNC or CRNC (DRNC). Iur signaling bearer is used.

In the first aspect, preferably, in releasing the MBMS service dedicated Iur signaling bearer, after the session starts, one RNC performs the MBMS UE Detach procedure for the last UE with the counterpart RNC while the MBMS service dedicated Iur signaling bearer When the session ends, one RNC releases an Iur signaling bearer dedicated to MBMS service while performing an MBMS UE Detach procedure with a counterpart RNC.

In the first aspect, preferably, the RNSAP message for controlling the MBMS service is exchanged between the RNCs using the SCCP connection-oriented transport service.

In a second aspect to achieve the object as described above, the present invention has a first and second wireless network controller, the first wireless network controller as a serving wireless network controller, and drift the second wireless network controller Has a wireless network controller, has at least one first mobile terminal for receiving broadcast service data, the second wireless network controller as a serving wireless network controller, and has the first wireless network controller as a drift wireless network controller; In a mobile communication system including at least one second mobile terminal for receiving service data and an SGSN for providing the broadcast service to the first and second radio network controllers, the SGSN is informed that the broadcast service is started. Thereafter, a signaling bearer for transmitting / receiving a message regarding the broadcast service is established in the first wireless network controller and the second wireless network control period. The method of claim 1, wherein the first wireless network controller establishes a signaling bearer for the first mobile terminal through an attach procedure that is first performed for the second wireless network controller for the broadcast service. And a second process of setting a signaling bearer for the second mobile terminal through an attach procedure that the second wireless network controller first performs with respect to the first wireless network controller for the broadcast service. It is characterized by including.

In the second aspect, preferably, the first wireless network controller sets a temporary identifier for allocating a signaling bearer for the first mobile terminal, and first attaches to the second wireless network controller. The temporary identifier is included in the message requesting to be transmitted.

In the second aspect, preferably, the second wireless network controller establishes a temporary identifier for allocating a signaling bearer for the second mobile terminal, and first attaches to the first wireless network controller. The temporary identifier is included in the message requesting to be transmitted.

In the second aspect, preferably, when the first mobile terminal no longer exists, the first wireless network controller performs the last touch on the second wireless network controller for the broadcast service. The method may further include the step of releasing the signaling bearer set up for the first mobile terminal through the procedure.

In the second aspect, preferably, when the SGSN is notified that the session of the broadcast service is terminated, the second wireless network controller is finally informed of the first wireless network controller due to the termination of the session of the broadcast service. The method may further include releasing the signaling bearer configured for the second mobile terminal through a Detach procedure to be performed.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. DETAILED DESCRIPTION In the following detailed description, one representative embodiment of the present invention is set forth in order to achieve the above technical problem. And other embodiments that can be presented with the present invention are replaced by the description in the configuration of the present invention.

In an embodiment of the present invention to be described later, in order to support the MBMS service, an MBMS service context is generated in several RNCs for the same service, and to exchange an RNSAP message between an MBMS service context of one RNC and an MBMS service context of another RNC. A dedicated Iur signaling bearer is generated for each MBMS service.

In the present invention, a method of generating a dedicated Iur signaling bearer for one MBMS service between two RNCs in a first embodiment in generating a dedicated Iur signaling bearer for each MBMS service, and a second embodiment between two RNCs in a second embodiment. We present a method for creating two dedicated Iur signaling bearers for one MBMS service.

4 is a diagram illustrating an example of defining one Iur signaling connection between two RNCs for one MBMS service according to a first embodiment. 4, a method of generating one dedicated Iur signaling bearer between the first RNC and the second RNC corresponding to one MBMS service will be considered. On the other hand, unlike the case of the existing unicast (Unicast) service, the multicast service is to receive a service through a single RNC multiple UEs for one service. Thus, while a specific RNC is an SRNC for some UEs that receive MBMS service, it may be a DRNC for other UEs, so it is impossible to distinguish the roles of the SRNC and the DRNC. Therefore, when the first RNC wants to send an RNSAP message for controlling the MBMS service to the second RNC and when the second RRN wants to send an RNSAP message for controlling the MBMS service to the first RNC, both cases of the same MBMS service-only Iur Use signaling bearer.

FIG. 5 shows an example in which two dedicated Iur signaling bearers corresponding to the same MBMS service are configured between two RNCs according to the second embodiment.

Referring to FIG. 5, among UEs receiving a particular MBMS service, a first dedicated Iur signaling bearer 510 is created for UEs having a first RNC as an SRNC and a second RNC as a DRNC. Next, among UEs provided with the specific MBMS service, a second dedicated Iur signaling bearer 520 is generated for UEs having the first RNC as the DRNC and the second RNC as the SRNC. Thereafter, the first RNC and the second RNC transmit the generated RNSAP message using an appropriate Iur signaling bearer according to whether the subject generating the RNSAP message for the MBMS service is an SRNC or a DRNC (CRNC).

As mentioned above, a multicast procedure must be newly defined in the RNSAP layer. The multicast procedure includes procedures for controlling a plurality of UEs that want to receive the same MBMS service for each MBMS service. The procedure is as follows.

(1) MBMS Attach Request [SRNC-> DRNC]; This message indicates that the UE receiving the MBMS service has moved to a cell managed by the DRNC. Parameters included in the message may be 'MBMS service identifier', 'M-RNTI', 'Signalling connection ID', 'Cell identifier list' and 'UE identifier list'.

(2) MBMS Detach Request [SRNC-> DRNC]; This message indicates that the UE receiving the MBMS service has left the cell managed by the DRNC. Parameters included in the message may be 'M-RNTI', 'Signalling connection ID', 'Cell identifier list', 'UE identifier list'.

(3) MBMS Information [DRNC-> SRNC]; This is a message for transferring MBMS related information such as PtP / PtM channel type determined by the CRNC from the DRNC to the SRNC. Parameters included in the message may be 'M-RNTI', 'Signalling connection ID', 'Cell identifier list', 'channel type', 'RB information'.

(4) MBMS p-t-m Transmission Initiation [DRNC-> SRNC]; This is a message for transmitting from the DRNC to the SRNC that the CRNC has decided to start transmitting the PtM channel. Parameters included in the message may be 'M-RNTI', 'Signalling connection ID', 'Cell identifier list', 'channel type'.

(5) MBMS p-t-m Transmission Termination [DRNC-> SRNC]; This is a message for transmitting from the DRNC to the SRNC that the CRNC has decided to terminate the PtM channel transmission. Parameters included in the message may be 'M-RNTI', 'Signalling connection ID', 'Cell identifier list', 'channel type'.

In order to perform the multicast procedures, information determined by the SRNC and notified to the DRNC, such as the UE's mobility information, is transmitted by the first dedicated Iur signaling bearer 510 defined by the present invention, and the PtP / PtM channel type. As such, the information determined by the DRNC and notified to the SRNC is transmitted by the second dedicated Iur signaling bearer 520 defined by the present invention. That is, the RNC may select an appropriate Iur signaling bearer among two Iur signaling bearers generated for each MBMS service according to whether the role played by the RNC is an SRNC or a CRNC.

For example, a first dedicated Iur signaling bearer 510 is used when the first RNC starts an MBMS Attach / Detach procedure to a second RNC, and a second dedicated when the second RNC starts an MBMS Attach / Detach procedure to the first RNC. Iur signaling bearer 520 is used. By doing this, even if the first RNC and the second RNC simultaneously transmit a message for controlling the same MBMS service, a collision can be prevented from occurring. In addition, even if the first RNC releases a dedicated Iur signaling bearer corresponding to a specific MBMS service by its own decision, the second RNC can transmit a message according to the specific MBMS service through the remaining one dedicated Iur signaling bearer. In contrast, even if the second RNC releases the dedicated Iur signaling bearer, the first RNC can transmit a message through the remaining one dedicated Iur signaling bearer.

1. Service context structure

According to an embodiment of the present invention, in order to establish a plurality of Iur signaling connections for each MBMS service between two RNCs, a structure of a new MBMS service context should be proposed.

6A and 6B illustrate the structure of an MBMS service context existing for each MBMS service in an RNC for supporting the present invention. FIG. 6A illustrates a configuration of an MBMS service context managed in response to a specific MBMS service before a session is started, and FIG. 6B illustrates a configuration of an MBMS service context managed in response to a specific MBMS service after a session is started. .

Referring to FIG. 6A, when a UE joins a service for a UE receiving an MBMS service in PMM-Connected mode, a list of services subscribed to by the UE is received from SGSN, and the MBMS service context generated in the RNC is generated. Let's look at the structure.

Reference numerals 611, 612, and 613 are identifiers for uniquely identifying the MBMS service. 'IP Multicast Address' and 'APN (Access Point Name)' of the reference number 611 are identifiers for distinguishing MBMS services. 'TMGI' of reference number 612 is an identifier temporarily assigned by GGSN or SGSN to distinguish the MBMS service currently in progress. 'M-RNTI' of the reference number 613 is an identifier assigned by the RNC to distinguish the MBMS service in the RNC. The RNC dynamically allocates the 'M-RNTI' value when an MBMS service context is created and releases the MBMS service context while deleting the MBMS service context. The 'M-RNTI' has a length shorter than the 'IP Multicast address' or the 'TMGI' to reduce overhead when transmitted over the air. 'State' of reference number 614 indicates whether an actual MBMS service is in progress. Receiving a message indicating that the session has started from the SGSN, the RNC sets the 'State' to Active. Receiving a message indicating that the session is finished from the SGSN, the RNC sets the 'State' to Standby. An example of the message indicating that the session has been started from the SGSN may be a session start message. An example of a message indicating that the session is completed from the SGSN may be a session stop message. 'Iu Signaling Connection Information' of the reference numeral 615 is signaling bearer information for transmitting and receiving a RANAP message for MBMS for controlling the MBMS between the RNC and the SGSN through the Iu interface. The Iu signaling bearer is not allocated for each UE but is allocated for each service, thereby enabling more efficient message transmission and management. Since the method of generating and managing the Iu signaling bearer is not related to the present invention, a detailed description thereof will be omitted. 'UE list information' of the reference number 616 is a list of UEs that make an RRC connection connection through the RNC and request MBMS service. The 'UE list' can be managed in two ways. In the first method, only the UE ID is included in the UE list, and the remaining information is interworked with the UE context in the RNC to query information whenever necessary. In this case, since the UE context must be searched at the required time, additional processing time for the search is required. The second method is a method of including the UE ID and the RRC state of the UE together in the UE list and managing the cell list or the URA list according to the RRC state of the UE. In this case, when there is a change in the UE context, i.e., when the UE makes a state transition, a cell update request, or a URA update request, information in the MBMS service context managed by the SRNC for the UE must also be changed. There is overhead.

Referring to FIG. 6B, the structure of the MBMS service context managed by the RNC after a session of a specific MBMS service is started will be described. In addition to the MBMS service context managed by the SRNC described above with reference to FIG. 6A, the MBMS service context shown in FIG. 6B receives QoS information, Iu signaling bearer, Iu data bearer, and the MBMS service for MBMS data transmission. It includes additional information for supporting the mobility of the UE. In order to support mobility of a plurality of UEs belonging to one MBMS service group, the MBMS service context in the RNC is SRNC information of UEs having the RNC as the CRNC as shown by reference numeral 630 and SRNC as the reference number 640. All DRNC information of UEs to be managed must be managed. Reference numerals 621, 622, 623, 624, 625, and 626 in FIG. 6B are the same as reference numbers 611, 612, 613, 614, 615, and 616 in FIG. 6A, and thus, detailed descriptions thereof will be omitted.

'Service Area Information' of the reference number 627 is a list of service area identifiers available for the corresponding MBMS service received through the SGSN from the BM-SC when the session starts. The RNC stores mapping information between any cell and the service area identifier. 'QoS' of reference number 628 is information such as data rate and service class that must be satisfied to support the MBMS service. The SGSN provides the QoS information at the start of a session or at the request of the RNC. 'Iu Transport Bearer Information' of reference number 629 is data bearer information to be used when transmitting MBMS data on the Iu interface. Since the MBMS data is transmitted using a packet service bearer, reference numeral 629 includes information such as an IP address of SGSN and a tunnel identifier of GPRS Tunneling Protocol (GTP). 'CRNC information' of reference number 630 stores information of UEs located in a cell managed by the RNC and radio bearer information for transmitting MBMS data. For the UEs receiving the same MBMS service in the same cell, the CRNC is the same. However, since the SRNCs of the UEs may be different from each other, the MBMS service context needs to manage SRNC information of several UEs. 'SRNC information' of reference numeral 650 stores information about the SRNC when the SRNC and the CRNC of the UE are different. After determining the channel type of PtP and PtM in the CRNC, the SRNCs of UEs receiving MBMS data through the CRNC transfer this information to the RNSAP such as 'MBMS ptm Transmission Initiation', 'MBMS ptm Transmission Information' or 'MBMS Information'. The information of reference numeral 650 is used to convey through the message. Looking at the 'SRNC information' of the reference number 650 in detail includes the following information. 'RNC ID' of reference numeral 651 is an ID of an SRNC. 'Iur Signaling Connection Information', which is indicated by reference numeral 652, is SCCP signaling connection information used for exchanging MBMS service-only RNSAP messages between the SRNC and the RNC between the SRNC and the RNC through an Iur interface. 'M-RNTI' of reference numeral 653 is an MBMS identifier allocated to identify the MBMS service allocated by the RNC corresponding to the RNC ID of the reference numeral 651. The reference numerals 651, 652, and 653 exist as many SRNCs as UEs located in a cell managed by the RNC.

'DRNC Information' of the reference numeral 640 is information on the DRNC for managing a cell where UEs belonging to the UE list of the reference numeral 626 are actually located. Conventionally, in the case of PtP service for one UE, one DRNC exists for one SRNC, but in case of MBMS service that multiple UEs receive simultaneously, one SRNC has several DRNCs. Here, several DRNCs are a set of DRNCs of several UEs. A detailed look at 'DRNC information' of reference number 640 includes the following information. 'RNC ID' of reference numeral 641 is an ID of a DRNC. 'Iur Signaling Connection Information' at 642 is MBMS service dedicated SCCP signaling connection information between the RNC and the DRNC where UEs belonging to the UE list of the fraudulent reference 626 are actually located. 'M-RNTI' of reference numeral 643 is an MBMS identifier allocated by the RNC corresponding to the RNC ID of the reference numeral 641 to identify the MBMS service. The reference numerals 641, 642, and 643 exist as many DRNCs of UEs in the UE list as indicated by reference numeral 626.

6B is a method for storing all information related to mobility of an individual UE in an MBMS service context. In another embodiment, information about mobility in a conventional UE context is used by using UE identifiers (U-RNTI, D-RNTI, C-RNTI) as key values, without storing information related to mobility of individual UEs in the MBMS service context. Reference is also possible. In another embodiment, the MBMS service context includes the same reference information 621, 622, 623, 624, 625, 626, 627, 628, 629, and 630. 'DRNC Information' of the reference number 640 includes only the information of the reference numbers 641, 642, and 643, and information corresponding to the Cell Information of the reference number 644 is used with reference to a corresponding UE context as necessary.

2. Iur Signaling Connection Setup Procedure

In the following description, when an event defined as Event 1 occurs, the first RNC starts Iur signaling connection establishment. In this case, the Iur signaling connection is established for each service. The event 1 refers to "when the first RNC transmits an MBMS Attach Request message to the second RNC for a specific MBMS service and there is no dedicated Iur signaling for the specific MBMS service between the first RNC and the second RNC. it means. When the first RNC transmits an MBMS Attach Request message, there are three representative cases as follows. In the first case, the first RNC transmits an MBMS Attach Request message to the second RNC in response to a UE having the first RNC as the SRNC and the second RNC as the DRNC after receiving the session start message from the SGSN. In the second case, after receiving the session start message, that is, after the session starts, the UE having the first RNC as the SRNC moves to a cell managed by the second RNC to transmit the MBMS Attach Request message to the second RNC. In the third case, after receiving the session start message, that is, the UE connected to the MBMS service late after the session starts, the first RNC receives the MBMS UE Linking Request message from the SGSN to perform an MBMS linking procedure. In this case, the MBMS Attach Request message is transmitted to the second RNC. In this case, the second RNC becomes a DRNC of the UE connected to the MBMS service later.

7 is a diagram illustrating a process of establishing an Iur signaling connection between two RNCs for controlling MBMS service according to an embodiment of the present invention. 7 may be applied to both the first and second embodiments of the present invention in common.

Referring to FIG. 7, in operation 701, the first RNC confirming occurrence of Evnet 1 executes an operation related to an MBMS service context corresponding to the MBMS service. The RNSAP layer 710 in the first RNC configures an MBMS UE Attach Request message based on the message that generated the event 1, and transmits the configured MBMS UE Attach Request message to the SCCP layer 711 in step 702. The SCCP layer 711 receives the MBMS UE Attach Request message and configures a SCCP message called a CR message as follows.

CR = [LR_RNC1, MBMS UE Attach Request]

The method of determining LR_RNC1 used for the CR message is the same as the conventional method. The SCCP layer 711 stores the determined LR_RNC1 in a predetermined area (item 642 of FIG. 6B) of the MBMS service context generated corresponding to the MBMS service. Thereafter, the SCCP layer 711 transmits the CR message to the second RNC in step 703.

The SCCP layer 721 of the second RNC receives the CR message and transmits an MBMS UE Attach Request message included in the payload portion of the CR message to the RNSAP layer 720 in step 704. After the SCCP layer 721 allocates LR_RNC2 corresponding to the CR message, the SCCP layer 721 generates an LR_RNC1 provided through the MBMS UE Attach Request message and the allocated LR_RNC2 corresponding to the MBMS service. In the area (reference numeral 642 in Fig. 6B). The RNSAP layer 720 performs a processing operation related to an internal MBMS service context using the MBMS UE Attach Request message. In step 705, the RNSAP layer 720 transmits an MBMS UE Attach Response message to the SCCP layer 721 as a response message corresponding to the MBMS UE Attach Request message.

The SCCP layer 721 configures an SCCP message called a CC message using the LR_RNC2 determined as follows.

CC = [LR_RNC2, LR_RNC1, MBMS UE Attach Response]

The CC message is a response message transmitted by the SCCP layer receiving the CR message to the SCCP layer transmitting the CR message in establishing an arbitrary SCCP connection. The SCCP layer 721 transmits the CC message to the SCCP layer 711 in step 706.

Upon receiving the CC message, the SCCP layer 711 of the first RNC stores the LR_RNC2 received through the CC message, and transmits the RNSAP message included in the CC message to the RNSAP layer 710 in step 707. . The LR_RNC2 is stored in a predetermined area (reference numeral 642 of FIG. 6B) of the MBMS service context generated corresponding to the MBMS service.

As described above, when the LR_RNC1 and the LR_RNC2 are shared by the first RNC and the second RNC, control information on the MBMS service may be transmitted by the LR_RNC1 and the LR_RNC2. For example, the first RNC configures and transmits an SCCP message using LR_RNC1 and LR_RNC2 stored in reference numeral 642 of FIG. 6B, and the corresponding second RNC uses the LR_RNC1 and LR_RNC2 of the received SCCP message to transmit the SCCP message. It is possible to determine which MBMS service the RNSAP message included in the message is.

3. Iur signaling disconnection procedure

In the following description, when an event defined as Event 2 occurs, the first RNC starts to release the Iur signaling connection. The event 2 refers to a case in which the first RNC transmits an MBMS UE Detach Request message to the second RNC and a second RNC corresponding to the DRNC for the last UE having the first RNC as the SRNC and the second RNC as the DRNC. This includes deleting the MBMS service context.

8 is a diagram illustrating a process of releasing an Iur signaling connection established between two RNCs for controlling MBMS service according to an embodiment of the present invention. 8 may be applied to both the first and second embodiments of the present invention in common.

Referring to FIG. 8, in operation 801, the first RNC confirming occurrence of Event 2 executes an operation related to an MBMS service context corresponding to the MBMS service. The RNSAP layer 810 in the first RNC configures an MBMS UE Detach Request message based on the message that generated the event 2, and transmits the configured MBMS UE Detach Request message to the SCCP layer 811 in step 802. The SCCP layer 811 receives the MBMS UE Detach Request message and configures a SCCP message called Released (RLSD) message. Thereafter, the SCCP layer 811 transmits the RLSD message to the second RNC in step 803.

The SCCP layer 821 of the second RNC receives the RLSD message and transmits an MBMS UE Detach Request message included in the payload portion of the RLSD message to the RNSAP layer 820 in step 804. The RNSAP layer 820 performs a processing operation related to an internal MBMS service context using the MBMS UE Detach Request message. The processing includes deleting LR_RNC1 and LR_RNC2 currently stored in the MBMS service context. Thereafter, the RNSAP layer 820 transfers an MBMS UE Detach Response message to the SCCP layer 821 as a response message corresponding to the MBMS UE Detach Request message in step 805. The SCCP layer 821 configures an SCCP message called a Release Complete (RLC) message. The SCCP layer 821 transmits the RLC message to the SCCP layer 811 in step 806.

Upon receiving the RLC message, the SCCP layer 811 of the first RNC releases LR_RNC1 and LR_RNC2 set in the current MBMS service context received through the RLC message, and releases the RNSAP message included in the RLC message in step 807. It delivers to the RNSAP layer 810.

As described above, LR_RNC1 and LR_RNC2 shared by the first RNC and the second RNC are deleted, and the SCCP connection between the first RNC and the second RNC is released.

4. Signaling procedure according to Iur signaling connection establishment / release

Hereinafter, a signaling procedure according to a second embodiment of the present invention will be described in detail. The signaling procedure according to an embodiment of the present invention to be described below is largely a procedure for establishing an Iur signaling connection (steps 910 to 921 and 930 to 931 of FIG. 9), and a procedure for transmitting a message through an Iur signaling connection (FIG. 9, steps 940, 950 to 951, and Iur signaling connection release (steps 960, 970 to 971, and 980 to 982). Meanwhile, the signaling procedure to be described later assumes that an MBMS service context corresponding to a specific MBMS service has already been created. The MBMS service context may be created by RNCs corresponding to SRNC of each UE before receiving a session by receiving an MBMS UE Linking Request message from SGSN or by receiving a Session Start message from SGSN when the session starts. Thereafter, after the session starts, the SRNC transmits a list of UEs to receive MBMS service to DRNCs of each UE.

9 is a diagram illustrating an example of a signaling procedure performed between an SGSN, a first RNC, and a second RNC in order to establish and release Iur signaling connection for each MBMS service according to a second embodiment of the present invention. In FIG. 9, the first RNC 901 and the second RNC 902 indicate an RNC providing a specific MBMS service, and the SGSN 903 indicates an SGSN constituting a CN for the specific MBMS service. Meanwhile, although not shown in FIG. 9, UEs receiving MBMS services through the first RNC 901 and the second RNC 902 may use the first RNC 901 as the SRNC and the second RNC 902 as the DRNC. It is assumed that it includes at least one first UE and at least one second UE with the first RNC as the DRNC and the second RNC as the SRNC.

Referring to FIG. 9, the SGSN 903 recognizes from a higher core network that a session is started. In operation 910, the session start message is transmitted to the second RNC 902. In operation 911, the session start message is transmitted to the second RNC 901. The session start message may request to establish a transport layer with a radio access bearer (RAB) of a user plane for Iu data transmission. In addition, considering Iu Flex, the first RNC 901 may receive a session start message from a plurality of SGSNs in addition to the SGSN 903. In this case, one of the plurality of SGSNs may be selected to set the RAB of the user plane, or the RAB of the user plane may be set to all SGSNs.

Upon receiving the session start message, the first RNC 901 and the second RNC 902 perform a preparation procedure for allocating radio resources for transmitting an MBMS service. As a preparation procedure, each RNC needs a process (hereinafter, referred to as a "count process") of identifying a number of UEs that want to receive a corresponding MBMS service in a cell managed by the RNC. To this end, a process of transferring a list of UEs that want to receive MBMS service from the SRNC to the DRNC is referred to as "MBMS Attach".

In response to the session start message, the second RNC 902 transmits an 'MBMS Attach Request message' requesting the MBMS Attach to the first RNC 901 in step 920. Parameters included in the 'MBMS Attach Request message' include 'Service ID', 'Cell ID list', and 'UE ID list'. The MBMS Attach requested by the second RNC 902 is for generating a dedicated Iur signaling bearer for UEs having the second RNC 902 as the SRNC and the first RNC as the DRNC. In step 921, the first RNC 901 transmits an MBMS Attach Response message to the second RNC 902 in response to the MBMS Attach Request message. Parameters included in the 'MBMS Attach Response message' include 'M-RNTI', 'Cell ID list', 'Channel Type', and 'Counting information'. The first RNC 901 and the second RNC 902 may share information necessary for transmitting a message from the first RNC 901 to the second RNC 902 in steps 920 and 921. . That is, a first dedicated Iur signaling bearer according to a specific MBMS service is generated from the first RNC 901 to the second RNC 902. In performing the steps 920 and 921, the first RNC 901 becomes a DRNC and the second RNC 902 becomes an SRNC.

In response to the session start message, the first RNC 901 transmits the MBMS Attach Request message to the second RNC 902 to request the MBMS Attach in step 930. Parameters included in the 'MBMS Attach Request message' include 'Service ID', 'Cell ID list', and 'UE ID list'. The MBMS Attach requested by the first RNC 901 is for generating a dedicated Iur signaling bearer for UEs having the first RNC 901 as the SRNC and the second RNC as the DRNC. In step 931, the second RNC 902 transmits an MBMS Attach Response message to the first RNC 901 in response to the MBMS Attach Request message. Parameters included in the 'MBMS Attach Response message' include 'M-RNTI', 'Cell ID list', 'Channel Type', and 'Counting information'. The second RNC 902 and the first RNC 901 may share information necessary for transmitting a message from the second RNC 902 to the first RNC 901 in steps 930 and 931. . That is, a second dedicated Iur signaling bearer according to a specific MBMS service is generated from the second RNC 902 to the first RNC 901. In performing steps 930 and 931, the first RNC 901 becomes an SRNC and the second RNC 902 becomes a DRNC.

Accordingly, two Iur signaling bearers are generated between the first RNC 901 and the second RNC 902 corresponding to one MBMS service by the above-described procedure.

Subsequently, it is assumed that a radio channel for transmitting MBMS data according to a specific MBMS service in which a current Iur signaling bearer is set in a cell controlled by the first RNC 901 is changed from a PtP mode to a PtM mode.

In step 940, the first RNC 901 determines to change the PtP mode set corresponding to the specific MBMS service to the PtM mode. The factors influencing the decision include the number of UEs to receive the specific MBMS service in the cell and the available radio resources of the cell. The first RNC 901 transfers the changed situation to the second RNC 902 through an MBMS p-t-m Transmission Initiation message in step 950. The 'MBMS p-t-m Transmission Initiation message' includes a 'Cell ID list'. The 'MBMS p-t-m Transmission Initiation Message' is transmitted by the first Iur signaling bearer generated previously. That is, since the subject that makes a decision to PtP / PtM is CNRC in the first RNC 901, the first Iur signaling bearer generated in steps 920 and 921 is used to transmit the MBMS p-t-m Transmission Initiation message. The second RNC 902 receiving the MBMS ptm Transmission Initiation message releases PtP resources previously configured for the specific MBMS service and prepares UEs to receive MBMS data in PtM mode. Perform tasks to send RRC messages. In this case, the RB information for receiving MBMS data in the PtM mode may be transmitted by the second RNC 902 to the corresponding UE through an RRC message or by the first RNC 901 using a control message through an MCCH. You can also inform. The second RNC 902 transmits an MBMS p-t-m Transmission Initiation Response message to the first RNC 901 in response to the MBMS p-t-m Transmission Initiation message in step 951. The 'MBMS p-t-m Transmission Initiation Response message' is transmitted by the second Iur signaling bearer generated previously. In performing steps 950 and 951, the first RNC 901 becomes a CRNC and the second RNC 902 becomes an SRNC.

Thereafter, it is assumed that there are no UEs provided with the specific MBMS service by the first RNC 901. This situation may occur when all UEs that have been provided with the specific MBMS service terminate reception of the specific MBMS service or move to another RNC. In the following description, it is assumed that the last UE provided with the specific MBMS service moves to another RNC.

The first RNC 901 detects in step 960 that the last UE receiving the specific MBMS service has moved to another RNC using the second RNC 902 as a DRNC. In other words, the UE detects that there is no longer the UE having the first RNC 901 as the SRNC and the second RNC 902 as the DRNC for the specific MBMS service. The first RNC 901 transmits an MBMS Detach Request message to the second RNC 902 to inform the second RNC 902 that there is no UE to provide the specific MBMS service. Parameters included in the 'MBMS Detach Request message' include 'Service ID', 'Cell ID list', and 'UE ID list'. The second RNC 902 transmits an MBMS Detach Response message in response to the MBMS Detach Request message to the first RNC 901 in step 971. By performing the MBMS UE Detach procedure according to steps 970 and 971, the second Iur signaling bearer configured for UEs using the first RNC 901 as the SRNC and the second RNC as the DRNC is released.

Thereafter, it is assumed that there are no UEs provided with the specific MBMS service by the second RNC 902. This situation may occur when all UEs that have been provided with the specific MBMS service terminate the session of the specific MBMS service or move to another RNC. In the following description, it is assumed that the session of the specific MBMS service is terminated.

The SGSN 903 transmits a session termination message to the second RNC 902 indicating that the session of the specific MBMS service is terminated in step 980. In step 981, the second RNC 902 transmits an MBMS Detach Request message corresponding to the session termination message to the first RNC 901. Parameters included in the 'MBMS Detach Request message' include 'Service ID', 'Cell ID list', and 'UE ID list'. The first RNC 901 transmits an 'MBMS Detach Response message' in response to the 'MBMS Detach Request message' to the second RNC 902 in step 982. By performing the MBMS UE Detach procedure corresponding to the termination of the session of the specific MBMS service in steps 981 and 982, the first Iur configured for UEs using the second RNC 902 as the SRNC and the first RNC as the DRNC. The signaling bearer is released.

When the session is terminated as described above, only the SRNCs have an MBMS service context corresponding to the specific MBMS service. The MBMS service context in the SRNC is an MBMS service context in which CRNC information (reference number 630 in FIG. 6B) and DRNC information (reference number 640 in FIG. 6B) are released and has a structure shown in FIG. 6A.

5. Actions according to Iur signaling connection establishment / release

10 is a diagram illustrating a control flow performed by an RNC for an embodiment of the present invention. That is, FIG. 10 schematically illustrates an operation of an RNC for generating or releasing an Iur signaling connection for each MBMS service to perform MBMS Attach and Detach functions.

Referring to FIG. 10, if an MBMS service context corresponding to a specific MBMS service is generated in SRNC by MBMS UE Linking procedure from SGSN, State information constituting the MBMS service context becomes valid. The state information is recorded in an item corresponding to reference numeral 614 in FIG. 6A or an item corresponding to reference numeral 624 in FIG. 6B.

In step 1000, the RNC examines state information of the MBMS service context and determines whether the state information is set to Active. If the State information is set to Active, the process proceeds to step 1002. If the State information is not set to Active, the process proceeds to step 1001. When the state information is not active, the transmission of MBMS data according to the specific MBMS service is not started. Therefore, in step 1001, the RNC checks whether a session start message indicating that a session of the specific MBMS service is started is received from SGSN. When the RNC receives the session start message in step 1001, the RNC proceeds to step 1006. However, if the session start message is not received in step 1001, the RNC proceeds to step 1000.

The RNC proceeds to step 1002 and determines whether a UE belonging to the UE list of the MBMS service context has moved to another cell. In order to determine whether the UE has moved to another cell, existing procedures for supporting mobility of the UE in the existing UTRAN may be used as it is. If the UE is in the Cell_PCH or Cell_FACH state, the UE reports to the SRNC of the UE through the Cell Update message, and if the UE is in the Cell_DCH state, the Meausrement Report RRC message. If the UE moves to another cell by the check in step 1002, the process proceeds to step 1006. However, if the UE has not moved to another cell by the check in step 1002, the process proceeds to step 1003. The RNC monitors whether an MBMS UE Linking Request message for a specific UE is received from the SGSN in step 1003. That is, in step 1003, the RNC checks whether there is a linking request for a UE connected to a service late after the session starts. If the reception of the MBMS UE Linking Request message is checked in step 1003, the process proceeds to step 1006. However, if the reception of the MBMS UE Linking Request message is not checked, the process proceeds to step 1004. Steps 100 to 1003 correspond to a process of determining whether an Iur signaling bearer generation or MBMS Attach procedure is required according to an embodiment of the present invention. If the Iur signaling bearer generation or MBMS Attach procedure is required by the above process, the RNC performs step 1006. In step 1006, the RNC performs related operations such as updating MBMS service context information according to the message received in steps 1001, 1002, and 1003.

In brief, the related operation, in step 1001, the RNC receiving the session start message sets the state information of the corresponding MBMS service context to Active. MBMS Service Area Information and QoS received from the session start message are set in the corresponding MBMS service context, and Iu transport Bearer Information, which is bearer information for receiving MBMS data from SGSN, is set. Meanwhile, when the SRNC and the DRNC are different from each other by referring to UE contexts of UEs included in the UE list of the MBMS service context, DRNC information of the corresponding MBMS service context is configured. Meanwhile, in step 1002, the RNC that detects the mobility of the UE updates DRNC information for the corresponding UE in the corresponding MBMS service context. Otherwise, the RNC receiving the MBMS UE Linking Request message for the specific UE in step 1003 adds the corresponding UE information to the UE list in the corresponding MBMS service context, and if the SRNC and the DRNC are different with reference to the UE context, the DRNC The UE information is added to the information as well.

After performing the related operation as described above, the RNC proceeds to step 1007. In step 1007, the RNC checks whether the SRNCs of UEs in the UE list of the MBMS service context coincide with the newly moved DRNC. To this end, reference may be made to UE contexts of UEs included in the UE list. If the set of DRNCs of the UEs included in the UE list includes n DRNCs, the check and the post-check step performed in step 1007 are repeated n times. If the SRNC corresponding to the specific UE and the DRNC do not match as a result of the check in step 1007, the process proceeds to step 1008. Otherwise, if the SRNC and the DRNC match, the flow proceeds to step 1015.

In step 1008, the RNC checks whether an Iur signaling bearer exists between the SRNC and the DRNC. If the Iur signaling bearer does not exist by the check in step 1008, the procedure proceeds to step 1015 after performing the procedure for generating the Iur signaling bearer in step 1009. The procedure for generating the Iur signaling bearer consists of a procedure performed in the SRNC and a procedure performed in the DRNC. The subroutine for the procedure performed in the SRNC is shown in detail in FIG. 11, and the subroutine for the procedure performed in the DRNC is shown in detail in FIG. 12. However, if the Iur signaling bearer exists by the check in step 1008, after performing the MBMS Attach procedure in step 1010 proceeds to step 1015. The MBMS Attach procedure consists of a procedure performed at the sender RNC and a procedure performed at the receiver RNC. The subroutine for the procedure performed in the transmitting RNC is shown in detail in FIG. 13, and the subroutine for the procedure performed in the receiving RNC is shown in detail in FIG. 14.

The SRNC proceeds to step 1011 when generation of the Iur signaling bearer is completed in step 1009. In step 1011, the SRNC compares the SRNC with the previous DRNC located before the UE, which is determined in step 1007, to move to the new DRNC. If the previous DRNC and the SRNC match by the comparison, the process proceeds to step 1015, otherwise proceeds to step 1012. For example, in step 1011, assuming that a certain UE has moved from the first DRNC to the second DRNC, it is checked whether the first DRNC matches the SRNC.

If the reception of the MBMS UE Linking Request message is not checked in step 1003 and proceeds to step 1004, the RNC checks whether a session termination message indicating that the session of the specific MBMS service is stopped is received from the SGSN. If the session end message is received by the check in step 1004, the flow proceeds to step 1005. However, if the session end message has not been received by the check in step 1004, the process proceeds to step 1000. In step 1005, the RNC checks whether the SRNCs of the UEs in the UE list of the MBMS service context corresponding to the specific MBMS service coincide with the newly moved DRNC. To this end, reference may be made to UE contexts of UEs included in the UE list. If the SRNC corresponding to the specific UE and the DRNC do not match as a result of the check in step 1005, the procedure proceeds to step 1014. Otherwise, if the SRNC and the DRNC match, the flow proceeds to step 1015.

On the other hand, if the previous DRNC and the SRNC do not match by the comparison in step 1011, and proceeds to step 1012, the RNC determines whether the moved UE is the UE that last received the specific MBMS service in the previous DRNC. . The determination can be made by referring to the MBMS service context and the UE context corresponding to the specific MBMS service. If it is determined that the comparison is not the last UE in step 1012, the RNC proceeds to step 1013. Otherwise, if the UE is the last UE, it means that the UE that is no longer provided with the specific MBMS service no longer exists in the previous DRNC. Accordingly, the RNC proceeds to step 1014 and performs a procedure for releasing the Iur signaling bearer set up for the specific MBMS service.

In step 1012 to step 1013, the RNC proceeds to step 1015 after performing the MBMS Detach procedure. The MBMS Detach procedure consists of a procedure by the transmitter of the RNC using the MBMS dedicated Iur signaling connection and a procedure by the receiver of the RNC using the MBMS dedicated Iur signaling connection. The subroutine for the procedure performed at the transmitter of the RNC is shown in detail in FIG. 15, and the subroutine for the procedure performed at the receiver of the RNC is shown in detail in FIG. 16.

On the other hand, if the session of the specific MBMS service is terminated or there is no longer a UE to provide the MBMS service, the RNC performs a procedure for releasing the Iur signaling bearer set up for the specific MBMS service in step 1014. Proceed to step 1015. The procedure for releasing the Iur signaling bearer consists of a procedure performed in the SRNC and a procedure performed in the DRNC. The subroutine for the procedure performed in the SRNC is shown in detail in FIG. 17, and the subroutine for the procedure performed in the DRNC is shown in detail in FIG. 18.

The SRNC updates the information of the MBMS service context according to the response message received from the RNSAP layer of the DRNC through steps 1009, 1010, 1013, and 1014, and then ends all operations according to the present invention. do.

5.1 Iur Signaling Bearer Creation Operation

FIG. 11 illustrates a subroutine of a procedure performed in an SRNC to generate an Iur signaling bearer according to an embodiment of the present invention, and FIG. 12 illustrates a DRNC to generate an Iur signaling bearer according to an embodiment of the present invention. The figure shows a subroutine for the procedure performed in FIG.

11 and 12, the SRNC allocates LR_SRNC for identifying an SCCP connection in preparation for configuring a new Iur signaling bearer in step 1101. In step 1103, the RNSAP layer of the SRNC generates an MBMS UE ATTACH REQUEST message corresponding to the RNSAP message and delivers it to the SCCP layer. The SCCP layer of the SRNC configures a CR message using the LR_SRNC determined above and the RNSAP message received from the RNSAP layer. The SCCP layer sends the CR message to the SCCP layer of the DRNC in step 1103.

The SCCP layer of the DRNC receives the CR message in step 1201 of FIG. 12, and detects that the SCCP layer of the SRNC is requesting a new SCCP connection establishment by the MBMS UE ATTACH REQUEST message included in the CR message. Meanwhile, the SCCP layer of the DRNC delivers an MBMS UE ATTACH REQUEST message included in the CR message to the RNSAP layer. In step 1203, the RNSAP layer processes an operation related to an MBMS service context corresponding to a specific MBMS service, based on the MBMS UE ATTACH REQUEST message. Thereafter, the RNSAP layer of the DRNC proceeds to step 1205 to generate an MBMS UE ATTACH RESPONSE message, which is a response message (RNSAP message) to the MBMS UE ATTACH REQUEST message, and delivers it to the SCCP layer. The SCCP layer of the DRNC allocates LR_DRNC for identifying an SCCP connection in step 1207. The SCCP layer of the DRNC configures a CC message using the allocated LR_DRNC and MBMS UE ATTACH RESPONSE message from the RNSAP layer. In operation 1209, the CC message is transmitted to the SCCP layer of the SRNC to determine that the SCCP connection establishment corresponding to the specific MBMS service has been successfully completed.

The SCCP layer of the SRNC receives the CC message in step 1104 of FIG. 11 to determine that the SCCP connection establishment with the DRNC has been successfully completed, and proceeds to step 1011 of FIG. 10.

5.2 MBMS Attach Procedure Using Created Iur Signaling Bearer

FIG. 13 is a diagram illustrating a subroutine of an MBMS Attach procedure performed in a transmitter of an RNC using an Iur signaling bearer generated by an embodiment of the present invention, and FIG. 14 is an Iur signaling generated by an embodiment of the present invention. A diagram showing a subroutine of the MBMS Attach procedure performed at the receiver of the RNC using a bearer.

Referring to the MBMS Attach procedure with reference to FIG. 13 and FIG. 14, the RNSAP layer of the SRNC generates an MBMS Attach Request message to inform that the UE has moved in step 1301. The RNSAP layer of the SRNC delivers the MBMS Attach Request message to the SCCP layer. The SCCP layer of the SRNC generates a DT (Data Transfer) message, which is an SCCP message including the MBMS Attach Request message, in step 1303 and transmits it to the SCCP layer of the DRNC. The DT message is transmitted through the MBMS service dedicated SCCP connection established by FIG. 11 and FIG. 12.

The SCCP layer of the DRNC receives the DT message in step 1401 of FIG. 14, and transfers an MBMS Attach Request message included in the DT message to the RNSAP layer of the DRNC. The RNSAP layer performs an operation related to an MBMS service context corresponding to a specific MBMS service based on the MBMS Attach Request message. In this case, when the UE causing the transmission of the MBMS Attach Request message is the first UE to receive the specific MBMS service in the DRNC, an MBMS service context corresponding to the specific MBMS service is generated, and the generated MBMS service is generated. Add the UE information to the context. Thereafter, the RNSAP layer of the DRNC generates an MBMS UE ATTACH RESPONSE message, which is a response message to the MBMS Attach Request message, in step 1405 and delivers the message to the SCCP layer of the DRNC. In step 1407, the SCCP layer of the DRNC generates a DT message using the MBMS UE ATTACH RESPONSE message and transmits the DT message to the SCCP layer of the SRNC. In this case, the DT message is transmitted through the MBMS service dedicated SCCP connection established by FIG. 11 and FIG. 12.

The SCCP layer of the SRNC receives the DT message in step 1305 of FIG. 13, transfers an MBMS UE ATTACH RESPONSE message included in the DT message to the RNSAP layer of the SRNC, and proceeds to step 1015 of FIG. 10.

5.3 MBMS Detach Procedure Using Created Iur Signaling Bearer

FIG. 15 is a diagram illustrating a subroutine of an MBMS Detach procedure performed at a transmitter of an RNC using an Iur signaling bearer generated by an embodiment of the present invention. FIG. 16 is an Iur signaling generated by an embodiment of the present invention. A diagram showing a subroutine for the MBMS Detach procedure performed at the receiver of the RNC using a bearer.

Referring to the MBMS Detach procedure with reference to FIG. 15 and FIG. 16, the RNSAP layer of the SRNC generates an MBMS Detach Request message to inform that the UE has moved to another DRNC in step 1501. The RNSAP layer of the SRNC delivers the MBMS Detach Request message to the SCCP layer. In step 1503, the SCCP layer of the SRNC generates a DT (Data Transfer) message, which is an SCCP message including the MBMS Detach Request message, and transmits it to the SCCP layer of the DRNC. The DT message is transmitted through the MBMS service dedicated SCCP connection established by FIG. 11 and FIG. 12.

The SCCP layer of the DRNC receives the DT message in step 1601 of FIG. 16, and transfers an MBMS Detach Request message included in the DT message to the RNSAP layer of the DRNC. The RNSAP layer performs an operation related to an MBMS service context corresponding to a specific MBMS service based on the MBMS Detach Request message in step 1603. At this time, the information on the UE that caused the transmission of the MBMS Detach Request message is removed from the MBMS service context. If the UE is the last UE receiving the specific MBMS service in the DRNC, the MBMS service context is released. Thereafter, the RNSAP layer of the DRNC generates an MBMS UE Detach Response message, which is a response message to the MBMS Detach Request message, in step 1605 and delivers it to the SCCP layer of the DRNC. In step 1607, the SCCP layer of the DRNC generates a DT message using the MBMS UE Detach Response message and transmits the DT message to the SCCP layer of the SRNC. In this case, the DT message is transmitted through the MBMS service dedicated SCCP connection established by FIG. 11 and FIG. 12.

The SCCP layer of the SRNC receives the DT message in step 1505 of FIG. 15, transfers an MBMS UE Detach Response message included in the DT message to the RNSAP layer of the SRNC, and proceeds to step 1015 of FIG. 10.

5.4 Iur signaling bearer release operation

FIG. 17 illustrates a subroutine of a procedure performed in an SRNC to release an Iur signaling bearer according to an embodiment of the present invention, and FIG. 18 illustrates a DRNC to release an Iur signaling bearer according to an embodiment of the present invention. The figure shows a subroutine for the procedure performed in FIG.

Referring to FIG. 17 and FIG. 18, the procedure for creating an Iur signaling bearer is released. Since the RNSAP layer of the SRNC no longer needs a dedicated Iur signaling connection with the other DRNC for the specific MBMS service in step 1701, the RNSAP layer is released. Creates an MBMS Detach Request message requesting and sends it to the SCCP layer. The SCCP layer of the SRNC generates an RLSD message, which is an SCCP message including the MBMS Detach Request message, in step 1703 and transmits it to the SCCP layer of the counterpart DRNC. The RLSD message is transmitted through the MBMS service dedicated SCCP connection established by FIGS. 11 and 12.

The SCCP layer of the DRNC receives the RLSD message in step 1801 of FIG. 18 and delivers an MBMS Detach Request message included in the RLSD message to the RNSAP layer of the DRNC. In step 1803, the RNSAP layer of the DRNC performs an MBMS service context related operation corresponding to the specific MBMS service using the MBMS Detach Request message. Here, the RNSAP layer releases the MBMS service context corresponding to the specific MBMS service. Thereafter, the RNSAP layer of the DRNC generates an MBMS UE Detach Response message, which is a response message to the MBMS Detach Request, in step 1805 and delivers it to the SCCP layer. In step 1807, the SCCP layer of the DRNC generates an RLC message using the MBMS UE Detach Response message and transmits the RLC message to the SCCP layer of the SRNC. The RLC message is transmitted through the MBMS service dedicated SCCP connection established by FIGS. 11 and 12. The SCCP layer of the DRNC releases the MBMS service dedicated SCCP connection established by the FIG. 11 and the FIG. 12 after transmitting the RLC message. That is, the LR_DRNC allocated for establishing the MBMS dedicated SCCP connection is released.

The SCCP layer of the SRNC receives the RLC message in step 1705 and delivers the MBMS UE DETACH RESPONSE message included in the RLC message to the RNSAP layer of the SRNC. Thereafter, the SRNC releases the MBMS service dedicated SCCP connection established by FIG. 11 and FIG. 12. That is, the LR_DRNC allocated for establishing the MBMS dedicated SCCP connection is released.

6. Message transmission operation through Iur signaling connection

Hereinafter, an operation of transmitting a message through an Iur signaling connection generated for each service in order to exchange MBMS service information between different RNCs according to an embodiment of the present invention will be described.

19 is a diagram illustrating a control flow in a transmitter of an RNC for transmitting a message using an MBMS dedicated Iur signaling connection according to an embodiment of the present invention, and FIG. 20 is a MBMS dedicated Iur according to an embodiment of the present invention. A diagram illustrating a control flow in a receiver of an RNC for transmitting a message using a signaling connection. In the following description, an RNC performing an operation of a transmitter is described as a first RNC, and an RNC performing an operation of a receiver is described as a second RNC.

In step 1901, the first RNC examines state information recorded in the corresponding MBMS service context. If the state information is set to Active, the first RNC proceeds to step 1903. However, if the State information is not set to Active, the operation according to the present invention ends.

The first RNC proceeds to step 1905 after processing the operation related to the MBMS service context in step 1903. The operation related to the MBMS service context may include counting the number of UEs receiving MBMS service through a specific cell, configuring a transport channel for transmitting MBMS data, and changing a configuration of a transport channel for transmitting MBMS data. Operation to perform. In operation 1905, the first RNC checks whether information is changed in relation to a specific MBMS service by an operation related to the MBMS service context. If it is changed, the process proceeds to step 1907, and if not changed, ends all operations according to the present invention.

When the first RNC proceeds to step 1907, the first RNC checks whether or not to transmit the changed information to another RNC (second RNC) where the UE is actually located. The inspection may be performed by determining whether the first RNC and the second RNC are the same. In this case, the information transfer to another RNC is required when the UE having the first RNC as the SRNC and the second RNC as the DRNC or the UE having the first RNC as the DRNC and the second RNC as the SRNC. This is a case where it is necessary to deliver changed information related to the specific MBMS service in 1RNC to the second RNC through an Iur interface. The first RNC proceeds to step 1909 if it is necessary to transfer the information. Otherwise, the first RNC ends all operations according to the present invention.

In step 1909, the RNSAP layer of the first RNC generates an RNSAP message for MBMS to inform the second RNC that the MBMS-related information has been updated, and delivers it to the SCCP layer of the first RNC. In step 1911, the SCCP layer of the first RNC finds a dedicated SCCP connection for the MBMS service set for the corresponding MBMS service in order to transmit the SCCP message by the RNSAP message. In this case, the first RNC selects an appropriate one Iur signaling connection among two Iur signaling connections established with the second RNC corresponding to one MBMS service. The appropriate Iur signaling connection may be selected by whether it transmits the message as the role of SRNC or the message as the role of DRNC. The SCCP layer of the first RNC generates a DT (Data Transfer) message, which is an SCCP message, using the RNSAP message previously transmitted in step 1913, and transmits the DT to the second RNC through the selected Iur signaling connection.

The second RNC receives the DT message in step 2001 of FIG. 20, and transfers the RNSAP message for MBMS included in the DT message to the RNSAP layer of the second RNC. The RNSAP layer of the second RNC performs an operation related to the MBMS service context based on the RNSAP message. Thereafter, the second RNC generates an RNSAP response message in response to the RNSAP message in step 2005 and delivers it to the SCCP layer of the second RNC. In step 2007, the SCCP layer of the second RNC generates a DT message including the RNSAP response message and transmits the DT message to the SCCP layer of the first RNC. The DT message is transmitted over the MBCP service dedicated SCCP connection selected by the first RNC.

In step 1915, the SCCP layer of the first RNC terminates the operation according to the present invention by receiving a DT message from the SCCP layer of the second RNC and delivering an RNSAP response message included in the DT message to the RNSAP layer.

As described above, the present invention sets up a plurality of Iur signaling connections for each MBMS service between two RNCs, so that the MBMS service-related information can be shared more efficiently. In particular, the DRNC processes an operation for the MBMS service. Has the advantage that can be delivered to SRNC. Has the effect of In addition, since Iur signaling connection is supported for each MBMS service, it is possible to efficiently manage a plurality of UEs belonging to one service group.

1 is a diagram schematically illustrating a network structure for providing an MBMS service in a typical mobile communication system.

2 is a diagram illustrating a signal flow for providing MBMS service between a UE and a network in a typical mobile communication system.

3 illustrates a procedure for creating a SCCP signaling connection to use a conventional connection oriented SCCP data transfer service.

4 illustrates an example of defining one Iur signaling connection between two RNCs for one MBMS service according to the first embodiment of the present invention.

5 illustrates an example of setting two dedicated Iur signaling bearers corresponding to the same MBMS service between two RNCs according to the second embodiment of the present invention.

6A and 6B illustrate the structure of an MBMS service context existing for each MBMS service in an RNC for supporting the present invention.

7 is a diagram illustrating a process of establishing an Iur signaling connection between two RNCs for controlling MBMS service according to an embodiment of the present invention.

8 is a diagram illustrating a process of releasing an Iur signaling connection established between two RNCs for MBMS service control according to an embodiment of the present invention.

9 is a diagram illustrating a signaling procedure in a mobile communication system for establishing and releasing Iur signaling connection for each MBMS service according to an embodiment of the present invention.

10 is a diagram illustrating a control flow performed by an RNC for an embodiment of the present invention.

FIG. 11 illustrates a subroutine for a procedure performed in an SRNC to generate an Iur signaling bearer according to an embodiment of the present invention. FIG.

12 illustrates a subroutine for a procedure performed in the DRNC to generate an Iur signaling bearer according to an embodiment of the present invention.

FIG. 13 illustrates a subroutine of an MBMS Attach procedure performed at a transmitter of an RNC using an Iur signaling bearer generated by an embodiment of the present invention. FIG.

FIG. 14 illustrates a subroutine of an MBMS Attach procedure performed at a receiver of an RNC using an Iur signaling bearer generated by an embodiment of the present invention. FIG.

FIG. 15 illustrates a subroutine of an MBMS Detach procedure performed at a transmitter of an RNC using an Iur signaling bearer generated by an embodiment of the present invention. FIG.

FIG. 16 illustrates a subroutine of an MBMS Detach procedure performed at a receiver of an RNC using an Iur signaling bearer generated by an embodiment of the present invention. FIG.

FIG. 17 illustrates a subroutine for a procedure performed in an SRNC to release an Iur signaling bearer according to an embodiment of the present invention. FIG.

FIG. 18 illustrates a subroutine for a procedure performed in a DRNC to release an Iur signaling bearer according to an embodiment of the present invention. FIG.

19 illustrates a control flow in a transmitter of an RNC for transmitting a message using an MBMS dedicated Iur signaling connection according to an embodiment of the present invention.

20 is a diagram illustrating a control flow in a receiver of an RNC for transmitting a message using an MBMS dedicated Iur signaling connection according to an embodiment of the present invention.

Claims (5)

At least one first mobile terminal for receiving a broadcast service using a first and a second wireless network controller, the first wireless network controller as a serving wireless network controller, and the second wireless network controller as a drift wireless network controller; At least one second mobile terminal for receiving the broadcast service using the first wireless network controller as a drift wireless network controller and the second wireless network controller as a serving wireless network controller, and the first and second wireless network controllers; In the mobile communication system including the SGSN for providing the broadcast service, after receiving a notification from the SGSN that the broadcast service is started, the message about the broadcast service in the first wireless network controller and the second wireless network control period. In the method for setting up a signaling bearer for transmitting and receiving, A first process of setting a signaling bearer for the first mobile terminal through an attach procedure that the first wireless network controller first performs for the broadcast service on the second wireless network controller; And a second process of setting a signaling bearer for the second mobile terminal through an attach procedure performed by the second wireless network controller for the first wireless network controller for the broadcast service. Characterized in that the method. The method of claim 1, wherein the first process comprises: Setting, by the first wireless network controller, a temporary identifier for allocating a signaling bearer for the first mobile terminal; And including the temporary identifier in a message requesting an attach procedure for the second wireless network controller for the first time. The method of claim 2, wherein the second process, Setting, by the second wireless network controller, a temporary identifier for allocating a signaling bearer for the second mobile terminal; And including the temporary identifier in a message requesting an attach procedure for the first wireless network controller for the first time. The method of claim 1, If the first mobile terminal no longer exists, the first mobile terminal is connected to the first mobile terminal through a detach procedure that is performed by the first wireless network controller to the second wireless network controller for the broadcast service. The method further comprises the step of releasing the signaling bearer set up for. The method of claim 4, wherein If the SGSN is notified that the session of the broadcast service is terminated, the second wireless network controller performs a Detach procedure last performed on the first wireless network controller due to the termination of the session of the broadcast service. And releasing the signaling bearer set up for the second mobile terminal.