WO2008046264A1 - Method of accessing multicast service for roaming user in mobile communication system - Google Patents

Abstract

A method of accessing multicast service for roaming user in mobile communication system includes: when roaming user who accesses home location GGSN from roaming location and requests broadcast-multicast service, home location BM-SC addresses and obtains the roaming location BM-SC of the user which performs the grant to the user and the APN indication of roaming location network, the home location BM-SC returns the APN to SGSN; when the roaming user accesses the MBMS service of the home location from the roaming location GGSN, the roaming location GGSN accesses the roaming BM-SC and addresses and obtains the home location BM-SC of the user which performs the grant to the user and the APN indication of roaming location network, and the roaming location BM-SC returns the APN to SGSN. In the invention, the access MBMS service requirement of roaming user could be solved, and MBMS service carrier router could be optimized, and the existing core network couldn't be modified.

Description

 TECHNICAL FIELD The present invention relates to a mobile communication system, and in particular, to a method for accessing a multicast broadcast service (MBMS) in a mobile communication system when a user roams. BACKGROUND OF THE INVENTION First, the English terms and abbreviations related to the present invention are described:

MBMS: Multimedia Broadcast/Multicast Service, multimedia broadcast/multicast service.

APN: Access Point Name, access point name.

SGSN: Service GSN, the network element responsible for mobility management on the core network side. GGSN: Gateway GSN, the core network side is responsible for accessing and sending out the network elements of the core network.

BM-SC: Broadcast-Multicast Service Centre, Broadcast Multicast Service Center.

PLMN: Public Land Mobile Network, Public Land Mobile Network. In order to effectively utilize mobile network resources, the existing mobile communication system proposes the idea of using multicast broadcast transmission services, that is, MBMS. MBMS provides a point-to-multipoint service in which a data source transmits data to multiple users in a mobile network. Network resource sharing, improve the utilization of network resources, especially air interface resources.

MBMS provides two methods: broadcast mode and multicast mode. MBMS can not only realize plain text low-rate message class multicast and broadcast, but also realize high-speed multimedia service multicast and broadcast, multicast and broadcast service MBMS based on WCDMA/GSM packet network, by adding some new functional entities. , such as the broadcast multicast service center BM-SC, add MBMS function to existing packets or functional entities such as SGSN (Packet Service Node), GGSN (Packet Gateway Node), RAN (Radio Access Network) and UE (User Terminal) And define a new logical shared channel to achieve air interface resource sharing. The network architecture using MBMS under the mobile communication system is shown in Figure 1. In Figure 1, except for the BM-SC, all are bearer network elements of the mobile communication system, and the data transmission is completed. Loss function. The signaling exchange between the GGSN and the BM-SC is performed at the Gmb reference point to implement the control plane of the MBMS, including the following signaling:

- The GGSN establishes the bearer context of the MBMS and registers with the BM-SC.

- The GGSN or BM-SC releases the MBMS bearer context, and the GGSN registers with the BM-SC. - The BM-SC informs the GGSN of the start and end of the session. Under the current MBMS framework, it is assumed that the BM-SC is always located in the home network (because the user information is stored in the BM-SC for authorizing the user and the applied service), and usually only one BM-SC is considered, GGSN Only interact with the default pre-configured BM-SC. For a mobile operator with a large regional span, the situation in which the single BM-SC is located in the home network cannot meet the requirements. Specifically, there are problems in the following scenarios:

1. According to the current MBMS framework, only one BM-SC is set in one PLMN, and some mobile communication networks have large coverage areas and inter-provincial roaming problems. It is impossible for a large mobile communication network to set only one BM- SC, there must be multiple BM-SCs, for example, one for each province.

2. When the GPRS service initiated by the roaming user is accessed through the home GGSN, it can only access the home BM-SC. At this time, the user may need to access the MBMS service of the roaming place, for example, the ground i or the characteristic Weather and other services.

3. When the GPRS service initiated by the roaming user is accessed through the roaming GGSN, the user can only access the BM-SC of the roaming place, and at this time, the user may still need to access the BM-SC of the home location. In summary, the problems existing in the prior art include: 1. In the case of roaming, the user wants to access the MBMS service of the roaming place or the home location but cannot complete the service authorization;

2. In the case of roaming, the user wants to access the MBMS service at the roaming or home location but cannot guarantee that the route is optimized. SUMMARY OF THE INVENTION The technical problem to be solved by the present invention is to provide a convergent solution for a variety of scenarios in which a roaming user accesses an MBMS service in a roaming manner, and comprehensively considers compatibility with the prior art. That is, a method for a mobile communication system roaming user to access a multicast service. In order to solve the above technical problem, the present invention provides a method for a mobile communication system roaming user to access a multicast service, which is used for setting a mobile communication network of a plurality of broadcast multicast service centers BM-SC, including the following steps: When the GGSN roaming to the homeland requests the broadcast multicast service of the roaming place, the method includes the following steps:

(1) The home GGSN initiates a broadcast multicast authorization request to the default home BM-SC;

(2) The home BM-SC queries the BM-SC of the roaming place according to the authorization request, and initiates an access point name APN query and a service-risk certificate request to the roaming BM-SC; (3) roaming place The BM-SC completes the APN indication of the service verification and the roaming network of the user according to the received APN query and the service verification request, and returns an APN query and a service verification response to the home BM-SC, where the APN information and the service verification result are carried. ;

(4) The home BM-SC returns a user authorization response to the home GGSN according to the response returned by the received roaming BM-SC, with the APN information and the authorization result, and finally the APN information carried by the GGSN. Returning to the SGSN of the roaming area, the SGSN activates the relevant broadcast multicast context according to the received new APN, and establishes a related tunnel. The present invention further includes: when the roaming user accesses the broadcast multicast service of the home location from the GGSN of the roaming place, the method includes the following steps:

(11) The roaming GGSN initiates a broadcast multicast authorization request to the default roaming BM-SC; (12) the roaming BM-SC queries the BM-SC of the home location according to the authorization request, and sends the BM-SC to the home BM- The SC initiates an access point name APN query and a service verification request;

(13) The home BM-SC completes the service verification of the user and the APN indication of the home network according to the received APN query and the service face certificate request, and returns an APN query and a monthly service certificate to the roaming BM-SC. The response, which carries the APN information and the monthly verification result; (14) The roaming BM-SC returns a user authorization response to the roaming GGSN according to the response returned by the received home BM-SC, with the APN information and authorization The result, and ultimately the GGSN The APN information carried therein is returned to the SGSN of the roaming place, and the SGSN activates the relevant broadcast multicast context according to the received new APN, and establishes a related tunnel. The present invention further provides a method for a mobile communication system roaming user to access a multicast service, which is applied to a mobile communication network in which a plurality of broadcast multicast service centers BM-SC are set, and includes the following steps: when a roaming user is from a roaming GGSN When accessing the broadcast multicast service of the home location, the steps include:

(a) roaming place GGSN initiates broadcast multicast 4 to the default roaming place BM-SC;

(b) roaming place BM-SC queries the BM-SC of the home location according to the authorization request, and initiates an access point name APN query and a good service request to the home BM-SC;

(c) The home BM-SC completes the APN query of the user and the APN indication of the home network according to the received APN query and service verification request, and returns an APN query and a monthly verification response to the roaming BM-SC. , carrying APN information and service verification results;

(d) The roaming BM-SC returns a user authorization response to the roaming GGSN according to the received response from the home BM-SC, with the APN information and the authorization result, and finally the APN information carried by the GGSN Returning to the SGSN of the roaming area, the SGSN activates the relevant broadcast multicast context according to the received new APN, and establishes a related tunnel. The invention completely solves the requirement for the roaming user to access the MBMS service, and the MBMS service carries the route optimization, and has no modification to the existing core network. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a network architecture diagram of an existing mobile communication system accessing an MBMS; FIG. 2 is a flowchart of a roaming user accessing a BM-SC when a roaming user accesses a GPRS through a home GGSN; The MBMS after the GGSN accesses the GPRS to access the BM-SC of the roaming place; the fL carries the routing diagram; FIG. 4 is a flowchart of the BM-SC accessing the home BM-SC when the roaming user accesses the GPRS through the roaming GGS; FIG. 5 is a diagram of an MBMS 7-loaded route after a roaming user accesses a home BM-SC when accessing GPRS through a roaming GGSN. DETAILED DESCRIPTION OF THE INVENTION The present invention divides a BM-SC into an access BM-SC and a service BM-SC. The access BM-SC refers to the default BM-SC corresponding to the GGSN to which the current multicast service is connected, and the service BM-SC refers to the BM-SC to which the service source belongs. When the access BM-SC is the service BM-SC, the routing of data is often optimal. #> According to this principle, the present invention achieves the consistency of two BM-SCs through authorization negotiation between BM-SCs and redistribution of GGSNs. Specifically, the following steps are included:

(1) When the user accesses the roaming MBMS service from the GGSN of the roaming place, or accesses the home MBMS service from the GGSN of the home location, the access BM-SC is the service BM-SC, and the two BM-SCs Negotiation of business authorization is required.

(2) When the roaming user requests the MME from the roaming location to the home station to request the MBMS service of the roaming place, the BM-SC of the home location (ie, accessing the BM-SC) according to the user's ID information (such as IMSI) and multicast The address can be addressed to the BM-SC of the user's roaming network, ie the service BM-SC, which completes the authorization for the user and the APN indication of the roaming network. The access BM-SC will authorize the successful response and the AP returns to the SGSN of the roaming place via the home GGSN, and the SGSN activates the relevant MBMS context according to the new APN to establish a related tunnel. This scenario is shown in the following embodiment 1.

(3) When the roaming user accesses the MBMS service of the home station from the GGSN of the roaming place, the roaming GGSN access first accesses the BM-SC, and accesses the BM-SC through the user ID information (such as IMSI) and the multicast address. The BM-SC, which is the home network of the user, ie the service BM-SC, can be addressed, the service BM-SC completing the authorization for the user and the APN indication of the home network. The access BM-SC returns the authorization success response and the APN back to the SGSN of the roaming area via the roaming GGSN, and the SGSN activates the relevant MBMS context according to the new APN to establish a related tunnel. This scenario is as shown in Embodiment 2 below. The specific implementation of the technical solution of the present invention is described in detail below with reference to the accompanying drawings: Embodiment 1: A roaming user joins a roaming BM-SC process. This process occurs when a user needs to join a roaming service based on an MBMS session. At this time, the user has established a GPRS route through the home GGSN. The process details are shown in Figure 2: except for steps 203a-d, all processes are the same as the existing standards. Step 201: If the user does not have an activated PDP context, the PDP context is activated at the UE, the roaming SGSN, and the home GGSN. Step 202: Send an IGMP join message to join the multicast group. Step 203a: The home GGSN receives the IGMP join message, and initiates an MBMS authorization request to the default home BM-SC. Step 203b: The home BM-SC receives the "MBMS authorization request initiated by the home GGSN, and the home BM-SC queries the roaming BM-SC according to the parameter IMSI and the multicast address and location information carried by the authorization request. Initiating an APN query and a monthly authentication request to the roaming BM-SC, the parameters are the IMSI and the multicast group address; Step 203c: The roaming BM-SC receives the APN query and the verification request sent by the home BM-SC ", for the user's IMSI and multicast group check, escape "APN query and service 3⁄4r certificate response", the parameter is the APN and -睑 certificate result of the roaming BM-SC. Step 203d: The attribution BM-SC receives according to The BM-SC returns a response, returns a user authorization response to the home GGSN, with the APN information and the authorization result, and finally returns the APN information carried by the GGSN to the SGSN of the roaming place. Step 204a: Ownership The GGSN sends an MBMS Notification request to the SGSN. Step 204b: The SGSN replies to the home GGSN to indicate whether the SGSN performs MBMS activation. Step 205: The SGSN requests the UE to perform MBMS context activation, and the 4 & APN is brought to the UE. The UE initiates an MBMS activation request, Step 207: The MBMS user context is not established, and the SGS will send an MBMS Notification reject message to the home GGSN, where 207a is the rejection request and 207b is the response. Step 208: If necessary, perform authentication on the user, perform Security function: Step 209: In A/Gb mode, if BSS Trace is activated, the SGSN will send a Trace request. Step 210: The SGSN establishes an MBMS context and parses the APN according to the BM-SC. _ To the roaming GGSN, send an MBMS Context Request to the roaming GGSN. Step 211: The roaming GGSN sends an MBMS authentication request to the roaming BM-SC. Where 211 a is an authorization request and 211 b is an authorization response. Step 212: If the roaming GGSN does not have the MBMS bearer context, initiate an MBMS registration request to the roaming BM-SC. 212a is a registration request and 212b is a registration response. Step 213: The roaming GGSN establishes an MBMS user context, and sends an establishment MBMS context response to the SGSN. Step 214: If the SGSN does not have the MBMS-enabled context, send an MBMS registration request to the roaming GGSN. Where 214a is the registration request and 214b is the registration response. Step 215: The SGSN provides the RAN with an MBMS user context. Step 216: The SGS replies to the MBMS activation and accepts to the UE. As shown in Figure 3, it is a schematic diagram of the route after successful MBMS activation. Specific Embodiment 2: A roaming user joins a home BM-SC process. This process takes place. The user needs to join a certain MBMS session-based service. At this point, the user has established a GPRS route through the roaming GGSN. The details of the process are shown in Figure 4: In addition to 403a-d, all processes are the same as existing standards. The route after successful MBMS activation is shown in Figure 5. Step 401: If the user does not have an activated PDP context, the PDP context is activated at the UE, the roaming SGSN, and the roaming GGSN. Step 402: Send an IGMP join message to join the multicast group. Step 403a: The roaming GGSN receives the IGMP join message and initiates an MBMS authorization request to the default roaming BM-SC. Step 403b: The roaming BM-SC receives the "MBMS authorization request" initiated by the roaming GGSN, and the roaming BM-SC queries the attribution BM-SC according to the parameter IMSI and the multicast address and location information carried in the authorization request. The home BM-SC initiates an APN query and a service verification request, and the parameters are IMSI and group 3⁄4 "group address; Step 403c: The home BM-SC receives the "APN query and monthly service verification request" sent by the roaming BM-SC, checks the user's IMSI and multicast group, and returns "APN query and service-certification response. The parameter is the APN of the home BM-SC and the verification result. Step 403d: The roaming BM-SC returns a user authorization response to the roaming GGSN according to the response returned by the received home BM-SC, with the APN information And the authorization result, and finally the AGN information carried by the GGSN is returned to the SGSN of the roaming place. Step 404a: The roaming GGSN sends an MBMS Notification request to the SGSN. Step 404b: The SGSN replies to the roaming GGSN, indicating whether the SGSN is performed. MBMS is activated. Step 405: The SGSN requests the UE to perform MBMS context activation, and brings the APN to the UE. Step 406: The UE initiates an MBMS activation request according to the received APN. Step 407: The MBMS user context is not established, and the SGSN will send the MBMS. The notification rejects the message to the roaming GGSN, where 407a is the reject request and 407b is the reply. Step 408: Perform security function according to the need, such as authenticating the user. Step 409: A/Gb mode If the BSS Trace is activated, the SGSN will send a Trace request. Step 410: The SGSN establishes an MBMS Context, and resolves to the Home GGSN according to the APN returned by the BM-SC, and sends an MBMS Context Request to the Home GGSN. Step 411: Home GGSN Sending an MBMS authentication request to the home BM-SC, where 411a is an authorization request and 411b is an authorization response. Step 412: If the home GGSN does not have the MBMS bearer context, initiate an MBMS registration request to the home BM-SC. The registration request, 412b is a registration response. Step 413: The home GGSN establishes an MBMS user context, and sends an establishment MBMS context response to the SGSN. Step 414: If the SGSN does not have the MBMS context, send the GGSN to the home GGSN.

MBMS registration request. Where 414a is the registration request and 414b is the registration response. Step Green 415: The SGSN provides the RAN with an MBMS User Context. Step 416: The SGS replies to the MBMS activation and accepts to the UE.

Claims

The method of claim, a method for a mobile communication system roaming user to access a multicast service, and a mobile communication network for setting a plurality of broadcast multicast service centers BM-SC, comprising the following steps:  When a roaming user requests a broadcast multicast service of a roaming place from a GGSN that is roaming to the home, the method includes the following steps:  (1) The home GGSN initiates a broadcast multicast authorization request to the default home BM-SC; (2) The home BM-SC queries the BM-SC of the roaming place according to the authorization request, and initiates an access point name APN query and a service verification request to the roaming BM-SC;  (3) The roaming BM-SC completes the service verification of the user and the APN indication of the roaming network according to the received APN query and the service verification request, and returns an APN query and a service verification response to the home BM-SC, where the APN is carried. Information and service verification results;  (4) The home BM-SC returns a user authorization response to the home GGSN according to the response returned by the received roaming BM-SC, with the APN information and the authorization result, and finally the APN information carried by the GGSN. Returning to the SGSN of the roaming area, the SGSN activates the relevant broadcast multicast context according to the received new APN, and establishes a related tunnel. The method of claim 1, further comprising:  When the roaming user accesses the broadcast multicast service of the home location from the GGSN of the roaming place, the steps include: (11) roaming place GGSN initiates a broadcast multicast authorization request to the default roaming place BM-SC; (12) The roaming place BM-SC queries the BM-SC of the home location according to the authorization request, and initiates an access point name APN query and a service verification request to the home BM-SC;  (13) The home BM-SC completes the APN query of the user and the APN indication of the home network according to the received APN query and the service verification request, and returns an APN query and a service verification response to the roaming BM-SC, where APN information and service verification results; (14) The roaming BM-SC returns a user authorization response to the roaming GGSN according to the response returned by the home BM-SC, which carries the APN information and the authorization result, and finally the APN information carried by the GGSN Returning to the SGSN of the roaming area, the SGSN activates the relevant broadcast multicast context according to the received new APN, and establishes a related tunnel. The method according to claim 1, wherein in the step (1), the parameter carried in the authorization request includes user identification information, multicast address information, and location information; and the step (2) The home BM-SC queries the BM-SC of the roaming area according to the user identification message, the multicast address information, and the location information. The method according to claim 2, wherein in the step (11), the parameter carried in the authorization request includes user identification information, multicast address information, and location information; and the step (12) The roaming BM-SC queries the BM-SC of the home location according to the user identification message, the multicast address information, and the location information. The method according to claim 3 or 4, wherein the user identification information comprises international mobile subscriber identity IMSI information. The method according to claim 1, wherein in the step (2), the parameters of the APN query and the service verification request are an IMSI and a multicast group address. The method according to claim 2, wherein in the step (12), the parameters of the APN query and the service verification request are an IMSI and a multicast group address. A mobile communication system roaming user accessing a multicast service, which is applied to a mobile communication network in which a plurality of broadcast multicast service centers BM-SC are provided, and the method comprises the following steps:  When the roaming user accesses the broadcast multicast service of the home location from the GGSN of the roaming place, the steps include: (a) roaming place GGSN initiates a broadcast multicast authorization request to the default roaming place BM-SC; (b) roaming place BM-SC queries the BM-SC of the home location according to the authorization request, and initiates an access point name APN query and a service verification request to the home BM-SC;  (c) The home BM-SC completes the service verification of the user and the APN indication of the home network according to the received APN query and the service verification request, and returns an APN query and a service verification response to the roaming BM-SC, where the APN is carried. Information and service verification results; (d) The roaming BM-SC # ^ returns the user's authorization response to the roaming GGSN according to the received BM-SC return response, with the APN information and the 4 吏 right result, and finally the GGSN will The carried APN information is returned to the SGSN of the roaming area, and the SGSN activates the relevant broadcast group insertion context according to the received new APN, and establishes a related tunnel.