KR20050059201A - Temporary mobile group identity generation and distribution method in roaming status - Google Patents

Abstract

The present invention relates to a method for generating and allocating TMGI for roaming UEs, the method comprising: a) when the UE joins a multicast group, sending a message to SGSN; b) SGSN obtaining TMGI of the service from GGSN C) SGSN modifying the roaming indication bit of the TMGI according to the roaming state of the UE; and d) SGSN sends a message to the UE and receives the modified TMGI. Accordingly, when the UE is roaming, the possibility of redundant allocation of TMGI is reduced, so that unity of TMGI is sufficiently maintained. As the quality of the content of the paging message is improved, the UE can determine whether the UE itself is a paging target.

Description

Temporary Mobile Group Identity Generation and Distribution Method in Roaming Status}

The present invention relates to a Multimedia Broadcast and Multicast Service (hereinafter referred to as 'MBMS'), and in particular, when a UE is roaming a Temporary Mobile Group Identity (TMGI) It relates to a method of generating and assigning.

MBMS is a new service being standardized by the 3rd Generation Partnership Project (hereinafter referred to as 3GPP). MBMS service is a unidirectional point-to-multipoint service, the most notable feature of which is the efficient use of radio and network resources. In this service, the multimedia data sent from the data source is transmitted to a number of users via the transmission network. The point-to-multipoint service can save radio resources. MBMS service is used in wireless communication network system such as Wideband Code-Division Multiple Access (WCDMA) and Global System for Mobile (GSM). Mainly used. The transmission of MBMS service data basically includes a data source transmission step, a relay network transmission step, a public transmission step at a destination cell, and a user reception step. FIG. 5 shows a diagram of a logical network device capable of providing MBMS service, where the MBMS service actually refers to a General Packet Radio Data Service (hereinafter referred to as GPRS) as a core transport network. use. As shown in FIG. 5, the broadcast / multicast service center (hereinafter referred to as 'BM-SC') is a data source for MBMS data transmission. The Gateway GPRS Supporting Node (hereinafter referred to as 'GGSN') is used to connect the GRPS network to an external network such as the Internet. The GGSN is used to connect the BM-SC to a specific Serving GPRS Supporting Node (hereinafter referred to as 'SGSN') in the MBMS service and transmit MBMS data to the SGSN. The cell broadcast center (hereinafter, referred to as 'CBC') is a data source for cell broadcast. In the MBMS service, by connecting the CBC and the BM-SC to each other, the CBC may be configured to provide the MBMS service notification function. SGSN is used for access control and mobility management for user equipment, and at the same time, it is also used to transfer MBMS data from GGSN to a specific Radio Network Controller (hereinafter referred to as 'RNC'). The RNC is used to control a group of base stations (hereinafter referred to as 'node B') and to transmit multimedia data to a specific node B. The base stations, under the control of the RNC, establish a physical channel in the air for MBMS service of a given cell. The user equipment (hereinafter referred to as 'UE') is a terminal device that receives MBMS service data.

6 shows the overall procedure for MBMS service, from service notification to user participation, service notification, radio bearer setup and user final withdrawal.

In step 000 (subscription), the relationship between the user and the service provider is established, and through this step, the user can receive the relevant MBMS multicast service data.

In step 001 (service notification), UEs are informed about services to be provided. As an example, the system may relay a soccer game at Paging at 7 pm.

Step 002 (participation) is a step in which a user joins one multicast group. That is, the user informs the network that he or she wishes to be provided with multicast mode data of a particular service.

In step 003 (MBMS multicast bearer setup), network resources for MBMS data transmission are set.

Step 004 (MBMS notification) informs UEs about future multicast data transmissions.

Step 005 (data transmission) is a step in which MBMS data is transmitted to the UEs.

Step 006 (MBMS multicast bearer release) is a step of releasing network resources for MBMS data transmission when there is no more MBMS data to be transmitted.

Step 007 (withdrawal) corresponds to step 002 (participation), in which the subscriber withdraws from the group, i.e., the user no longer wants to receive the multicast mode data for the specific service. It's a step.

Since the MBMS service is provided to multiple users at the same time, paging blocks are likely to occur during the procedure of MBMS service notification. One Temporary Mobile Group Identity (TMGI) is assigned to users of the same group, which makes it possible to address the lack of paging multiple users one at a time. Here, the TMGI represents a service identifier of a multicast service in a wireless mobile network. TMGI uses UEs by SGSN prior to MBMS service data transmission, through route area updates or packet-temporary mobile subscriber identifier (P-TMSI) reallocation procedures. Is sent to. Initial assignment will be performed when the user joins the MBMS service. Different multicase services will have different TMGIs in the same SGSN. TMGI makes it possible to prevent signaling blocks in the air interface during paging.

TMGI may be assigned by GGSN or BM-SC to ensure unity in Public Land Mobile Network (PLMN). However, if the UE is roaming to another public land mobile network, there is no guarantee that the same TMGI as the TMGI of the home PLMN is not present in the accessing PLMN that it is trying to access. . If TMGI has been assigned redundantly, confusion may occur when SGSN sends paging to UE, and as a result, paging failure will be repeated many times.

1 is a signal flow diagram illustrating a path region update procedure for a roaming UE.

2 is a signal flowchart for solving a paging problem when a TMGI is duplicately allocated.

3 is a signal flow diagram illustrating a TMGI allocation procedure when a UE joins an MBMS service multicast group.

4 is a flowchart illustrating a procedure of generating a TMGI roaming indication bit.

5 is a block diagram illustrating a logic network device for MBMS service.

6 is a flowchart illustrating an MBMS service multicast service.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to assign a TMGI when the UE is in a roaming state so that the same TMGI can prevent or reduce the likelihood of representing different MBMS services. To provide.

Another object of the present invention is to provide a method for configuring a multicast / broadcasting service using one identifier in a wireless network system.

In order to achieve the above objects, according to an embodiment of the present invention, in a mobile network system, a method for assigning a Temporary Mobile Group Identity (TMGI) indicating a service identifier of a multicast service for a user equipment (UE) A method comprising: a) when a UE joins a multicast or broadcast service, the UE sends a message to a Serving GPRS Supporting Node (SGSN) b) SGSN sends a service context for the service to a Gateway GPRS Supporting Node (GGSN) And receiving a response message including the TMGI from the GGSN c) setting a roaming indication bit of the TMGI according to whether the UE is roaming; and d) the roaming indication bit set together with the roaming indication bit. And transmitting a message including a TMGI to the UE.

In addition, according to another embodiment of the present invention for achieving the above object, in a method for configuring a multicast or broadcast service in a mobile network system: a) a Serving GPRS Supporting Node (SGSN) is a Gateway GPRS Supporting Node (GSGN); Obtaining the service from b) the SGSN sending a paging message to the UE including a TMGI, IP multicast addresses of the service or a public land mobile network identification number; c) the UE sending the paging message When receiving, the UE checks whether the TMGI, IP multicast addresses or the public land mobile network identification number matches the UE's own TMGI, IP multicast addresses or public land mobile network identification number. D) the TMGI, IP multicast addresses or the public land mobile network Discarding the paging message when the identification number does not match the UE's own TMGI, IP multicast addresses or public land mobile network identification; and e) the TMGI, IP multicast addresses or public land mobile. When the network identification number matches the UE's own TMGI, IP multicast addresses or public land mobile network identification number, requesting the service from the SGSN using the received TMGI.

Accordingly, when the UE is roaming, the possibility of redundant allocation of TMGI is reduced, so that unity of TMGI is sufficiently maintained. In addition, the quality of the content of the paging message is improved so that the UE can determine whether the UE itself is a paging target.

1) Generation method of TMGI roaming indication bit

When SGSN pages an MBMS service multicast group, the SGSN uses TMGI. When the SGSN joins a multicast group, the TMGI for a given MBMS service is generated by the GGSN or BM-SC and assigned to that SGSN. The SGSN determines whether the service is for a local UE or a roaming UE. The SGSN sets the roaming indication bit of the TMGI in accordance with the result of the determination. For example, the roaming indication bit of the TMGI may be set to '0' for a local UE and '1' for a roaming UE.

2) TMGI Allocation Procedure for Roaming UE

In general, TMGI is obtained by assignment while the UE joins one MBMS service multicast group. However, for a roaming UE, when the UE updates its route area, SGSN recognizes the TMGI of the MBMS service the UE is participating in, modifies the TMGI in the response message, and a new TMGI is in the response message. It is included and transmitted to the UE.

3) Signaling procedure for TMGI duplication

If the same TMGI is assigned for different services from two different public land mobile networks, if SGSN sends paging, different roaming users will receive a paging message with the TMGI. The paging message will also carry an APN and IP multicast addresses or a public land mobile network identification number, which helps the UEs verify that the service belongs to them.

4) New Paging Message

If the SGSN recognizes that the paging target is a roaming UE, the SGSN includes the APN and IP multicast addresses or public land mobile network identification numbers in the paging message and forwards them, allowing the UE to distinguish them. . Parameters in paging include APN and IP multicast addresses or public land mobile network identification numbers.

4 shows a procedure for generating a TMGI roaming indication bit. After SGSN first joins the MBMS Service Multicast Group, SGSN can obtain a TMGI for this service assigned by GGSN or BM-SC from GGSN. The SGSN holds a mapping relationship between the APGI and the IP multicast addresses of the TMGI and the corresponding MBMS service, and maintains the mapping relationship between the TMGI and the UE identification number. SGSN checks whether the UE is roaming, sets the TMGI roaming indication bit according to whether the UE is roaming, and informs the UE of the TMGI through the corresponding message.

1 shows a route area update procedure for a roaming UE. When the UE has reached the new route region, the UE will send a route region update request message to the new SGSN. The new SGSN and the old SGSN exchange MBMS service context for the UE, whereby the new SGSN is not only with the multicast group's TMGI, but also with APN and IP multicast addresses. Get to know the MBMS service multicast group. If the SGSN finds that the UE is roaming, the SGSN modifies the roaming indication bit of the TMGI and informs the UE of the new TMGI during the path region update acceptance.

3 shows a TMGI allocation procedure for a case where a UE joins an MBMS service multicast group. When the UE joins one MBMS service multicast group, the UE sends an "Activate MBNS service context request" message containing the APN and IP multicast addresses of the MBMS service to the SGSN. After receiving the request, the SGSN sends an MBMS context request message to the GGSN and receives a response message from the GGSN containing the TMGI assigned by the GGSN or BM-SC. If the SGSN finds that the UE is a local user, the SGSN sets a TMGI roaming indication bit according to the roaming state of the UE, and sets an "Activate MBMS service context" for the TMGI configured with the roaming indication bit to the UE. Informed via accept "message.

2 shows a procedure for solving a paging problem when a TMGI is repeatedly allocated. With the same TMGI assigned for different services, if the SGSN pages this kind of TMGI, the paging message will carry the APN and IP multicast addresses or public land mobile network identification. When UE 1 and UE 2 receive this paging message, UE 1 and UE 2 determine whether the APN and IP multicast addresses are the same as those of the MBMS service multicast group to which they participate, or the public land mobile network identification number. Will check whether or not matches each UE's own network identification number. If the parameters received by UE 1 match those that UE 1 itself is storing, UE 1 will send a service request to SGSN. On the other hand, if the parameters of UE 2 do not match those that UE 2 itself is storing, UE 2 does not need to respond.

According to the present invention having the above configuration, when the UE is roaming, the possibility of redundant allocation of TMGI is reduced, so that unity of TMGI is sufficiently maintained. In addition, the quality of the content of the paging message is improved so that the UE can determine whether the UE itself is a paging target.

Claims (3)

In a mobile network system, a method of assigning a Temporary Mobile Group Identity (TMGI) indicating a service identifier of a multicast service for a user equipment (UE): a) when the UE joins a multicast or broadcast service, sending the message to a Serving GPRS Supporting Node (SGSN) b) SGSN requests a service context for the service to a Gateway GPRS Supporting Node (GGSN) and receives a response message from the GGSN containing the TMGI. c) setting a roaming indication bit of the TMGI according to the roaming state of the UE; d) transmitting a message including the TMGI set together with the roaming indication bit to the UE. The method of claim 1, The SGSN further comprises the step of modifying the TMGI obtained from the GGSN and modifying the roaming indication bit according to the roaming state of the UE. A method for setting up multicast or broadcast services in a mobile network system: a) the Serving GPRS Supporting Node (SGSN) obtaining the service from a Gateway GPRS Supporting Node (GGSN) b) the SGSN sending a paging message to the UE including a TMGI, IP multicast addresses of the service or a public land mobile network (PLMN) identification number; c) when the UE receives the paging message, the TMGI, IP multicast addresses or public land mobile network identification number matches the UE's own TMGI, IP multicast addresses or public land mobile network identification number Checking at the UE whether to d) discarding the paging message when the TMGI, IP multicast addresses or public land mobile network identification number does not match the UE's own TMGI, IP multicast addresses or public land mobile network identification number; and , e) SGSN using the received TMGI when the TMGI, IP multicast addresses or public land mobile network identification number matches the UE's own TMGI, IP multicast addresses or public land mobile network identification number. And requesting the service from the service provider.