CN100484147C - Method for determining number of receiving users in multimedia broadcast/multicast service - Google Patents

Abstract

The invention discloses a method for determining the number of receiving users in a multimedia broadcast/multicast service MBMS. The method includes: 1) During the session start process, the core network side sends an inquiry identifier to the base station controller BSC/radio network controller RNC , the inquiry identifier is used to indicate whether the BSC/RNC inquires whether the UE receives the MBMS session; 2) before the BSC/RNC establishes radio resources, the BSC/RNC judges whether the inquiry identifier received from the core network side is valid, and if it is valid, sends The UE inquires whether to receive the MBMS session, and determines the number of receiving UEs according to the response returned by the UE; otherwise, determines the number of receiving UEs according to the fact that all UEs that have activated the MBMS service are willing to receive the session. Applying the method of the invention can reduce the waste of wireless network interface resources and simplify the network signaling process. Avoid unnecessary UE response process, make UE more power-saving, and increase UE standby time.

Description

Method for Determining Number of Receiving Users in Multimedia Broadcast/Multicast Service

technical field

The invention relates to a method for realizing the transmission of multimedia broadcast/multicast services, in particular to a method for determining the number of receiving users in the multimedia broadcast/multicast service (MBMS).

Background technique

With the development of the third-generation mobile communication technology, the third-generation mobile communication can provide services with a higher data rate than the second-generation mobile communication, thereby supporting various business forms. Services such as video calls, picture downloads, and high-speed Internet browsing. The characteristic of one type of service is that the service can be sent to user equipments (UEs) in the wireless network that have subscribed to the service at the same time. For example, weather forecasts, news clips, sports highlights and so on. Utilizing the characteristics of simultaneous transmission of these services, the third generation mobile communication introduces the concept of multicast/broadcast.

Referring to Fig. 1, Fig. 1 is a schematic diagram of the working principle of MBMS. Among them, for an intermediate node, for example: 10 or 101 or 102 in the figure, its upstream node always sends a piece of data to the intermediate node; Copy the data, and distribute the data to the downstream nodes expecting to receive the data. In this way, each branch of the multicast/broadcast service data transmission tree has only one piece of data for transmission, occupying one piece of transmission resources, and the root node and its The same is true for data transfers to downstream nodes. The only difference between the multicast service and the broadcast service is that the multicast service only sends corresponding information to UEs that have subscribed to certain information, while the broadcast service sends information to all UEs in the wireless network. It can be seen from the above description that providing the same information to a large number of UEs at the same time through the multicast/broadcast service can greatly save network resources.

Referring to FIG. 2, FIG. 2 is a schematic structural diagram of a wireless network supporting multicast/broadcast services. As shown in Figure 2, the wireless network structure supporting multicast/broadcast services in the existing 3rd Generation Partnership Project (3GPP) is that the broadcast/multicast service center (BM-SC) 201 is common to the gateway through the Gmb interface or the Gi interface The packet radio service (GPRS) support node (GGSN, Gateway GPRS Support Node) 202 is connected, and one BM-SC 201 can be connected with multiple GGSN 202; GGSN 202 is connected with the service GPRS support node (SGSN, Serving GPRS Support Node) Node) 203 is connected, a GGSN 202 can be connected with multiple SGSN 203; SGSN 203 can be connected with Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (UTRAN) 204 through Iu interface, then UTRAN204 is connected with communication terminal 206 through Uu interface The SGSN 203 can also be connected with the Global System for Mobile Communications (GSM) Enhanced Radio Access Network (GERAN) 205 through the Iu/Gb interface, and then the GERAN 205 is connected with the communication terminal 206 through the Um interface.

The MBMS bearer context is used to save the MBMS bearer capability. The context contains all information descriptions defining an MBMS service bearer. The context is created on all nodes that bear MBMS data. Referring to Table 1, the MBMS bearer context includes: IP multicast address, APN, TMGI, State, required MBMS bearer capability, QoS, MBMS service area, downstream node list, number of UEs, etc. Among them, the IP multicast address identifier is carried by the MBMS bearer described by the MBMS bearer context; APN is the name of the access point whose IP multicast address has been defined; TMGI is the temporary mobile group identifier assigned to the MBMS bearer; State is the MBMS bearer The activity state ('stationary' or 'activated') indicates whether it is required to establish bearer plane resources for MBMS data transmission; the required MBMS bearer capability indicates the minimum bearer capability that the UE needs to support. QoS is the quality of service required by the MBMS bearer; the MBMS service area is the area where the MBMS service needs to be sent; the downstream node list is a list of downstream nodes that have requested the MBMS bearer and MBMS data must be delivered to; the number of UEs is the node that the node owns The number of UEs that have joined the multicast service.

parameter describe RAN SGSN GGSN BM-SC IP multicast address The IP multicast address identifies the MBMS bearer described by this MBMS bearer context x x x x APNs The IP multicast address has been defined as the access point name x x x to be studied TMGI Temporary mobility group identifier assigned to MBMS bearer x x x x State Activity state of the MBMS bearer ('stationary' or 'active') to be studied x x x Required MBMS bearer capacity Identifies the minimum bearer capability that the UE needs to support x x x QoS The quality of service required by the MBMS bearer x x x x MBMS service area The area where the MBMS service needs to be sent x x x x List of downstream nodes The MBMS bearer is requested, and the downstream node list to which the MBMS data must be delivered x x x Number of UEs The number of UEs owned by the node that have joined the multicast service to be studied x x to be studied

Table I

An existing MBMS session process includes two parts: first, the core network notifies the RNC that an MBMS session is about to start; then the BSC/RNC establishes necessary radio resources for transmitting MBMS data to interested UEs. Wherein, whether the BSC/RNC establishes a radio bearer, establishes a point-to-point radio bearer or a point-to-multipoint radio bearer is determined by the BSC/RNC by performing a counting process.

The MBMS session start procedure is triggered when the BM-SC is ready to send data. The session start procedure activates all required bearer resources in the network for transmitting MBMS data and informs interested UEs that data transmission is about to start. Through this process, BM-SC provides session attributes such as MBMS QoS, MBMS service domain, and estimated session length parameters (if any) to interested relevant network nodes. Through this process, the relevant RNC will be triggered to perform tasks such as session notification in the access network, cell UE counting, radio bearer type selection, and wireless and wired bearer plane establishment.

With regard to the network structure shown in FIG. 2 , the following introduces the MBMS session process in the prior art.

Referring to FIG. 3 , FIG. 3 is a schematic diagram of an MBMS session start flow in the prior art. The process includes the following steps:

Step 301, the BM-SC sends a session start request message (Session Start Request) to the GGSN stored in the "downstream node list" parameter in its corresponding MBMS bearer context, indicating the transmission to be started, and setting the state attribute of the MBMS bearer context to be "activation". The request provides session attributes such as QoS, MBMS service domain, and estimated length of the session.

Step 302, after the GGSN receives the session start request message, save the session attribute provided in the message in the MBMS bearer context, set the status attribute of the MBMS bearer context to "activate", and send a session start response message to the BM-SC ( Session Start Response).

Step 303, the GGSN sends an MBMS session start request message (MBMS SessionStart Request) to the SGSN stored in the "downstream node list" parameter in the corresponding MBMS bearer context.

Step 304, after the SGSN receives the MBMS session start request message, save the session attribute in the MBMS bearer context, and set the state attribute of the MBMS bearer context as "activation", and send an MBMS session start response message (MBMS Session StartResponse) to the GGSN, The message provides a tunnel termination identifier (TEID) for the bearer plane, which is used for the GGSN to send MBMS data.

In step 305, the SGSN sends an MBMS Session Start Request message (MBMS Session Start Request) to each BSC/RNC connected to the SGSN, which contains session attributes.

Step 306, the BSC/RNC judges whether it is in the MBMS service domain, if the BSC/RNC is in the MBMS service domain, then first in the MBMS bearer context, save the session attribute, set the status attribute of the MBMS bearer context to "activate", and then perform the steps 307 ; otherwise, directly execute step 307 .

Step 307, BSC/RNC sends an MBMS session start response message (MBMS Session Start Request) to SGSN.

A BSC/RNC receives multiple MBMS session start request messages, which carry Iu bearer plane parameters, and returns only one MBMS session start response message, which is used to establish an Iu plane bearer to an SGSN.

If the BSC/RNC is in the MBMS service domain, the BSC/RNC includes the TEID in the MBMS session start response message, which is used for the Iu bearer plane used by the SGSN to send MBMS data.

If the BSC/RNC is not in the MBMS service domain, the MBMS session start response message sent to the SGSN indicates that the BSC/RNC is not in the MBMS service domain.

Then, BSC/RNC can establish necessary radio resources for transmitting MBMS data to interested UEs in the MBMS service domain.

In the prior art, when the BSC/RNC receives the MBMS session start message sent by the SGSN, it counts the number of UEs expecting to receive the MBMS session in each cell in the BSC/RNC, so as to decide whether to send the MBMS session in the cell data.

Referring to FIG. 4, FIG. 4 is a flow chart of BSC/RNC collecting statistics on receiving UEs. The process consists of the following three steps:

In step 401, the BSC/RNC sends an inquiry message to the UE in the cell that has activated the MBMS service, asking the UE whether to receive the MBMS session.

Step 402, the UE that agrees to receive the MBMS session returns an inquiry response message to the BSC/RNC.

In step 403, the BSC/RNC counts the UEs that returned the response of agreeing to receive, and determines the number of receiving UEs according to the statistical results. The specific method is: if the inquired UE agrees to receive the MBMS session, the BSC/RNC will record the UE that has returned the response of agreeing to receive the MBMS session into the number of UEs expecting to receive the MBMS session; otherwise, the BSC/RNC will not register the UE Enter the number of UEs expecting to receive the MBMS session.

BSC/RNC pre-sets a UE counting threshold value. If the total number of UEs expecting to receive the MBMS session does not reach the UE counting threshold value after counting all UEs that return responses, the total number is determined to be established. The number of receiving UEs in the radio bearer mode. If the total number of UEs expecting to receive the MBMS session reaches the UE number threshold during the process of counting the UEs that return responses, the BSC/RNC stops receiving inquiry response messages returned by other UEs, and the UE count threshold is Determine the number of receiving UEs to establish the radio bearer mode.

BSC/RNC decides whether to send according to the number of UEs expecting to receive the MBMS session. If it is sent, the corresponding way of establishing radio resource bearers is also determined according to the number of UEs expecting to receive the MBMS session and other RRM algorithms. When the number of UEs expected to be received is relatively small, that is, the number of UEs has not reached the counting threshold, the point-to-point transmission method is adopted; when the number of UEs is relatively large, that is, the number of UEs reaches the counting threshold, Use point-to-multipoint transmission.

At present, the MBMS service can carry various services, including services such as video and audio that need to be confirmed by the UE; services such as text, small pictures, file downloads, and advertisements that do not need to be confirmed by the UE. However, if the BSC/RNC also continues to inquire about the UE adding the following services that do not require the UE to confirm reception, the load on the radio interface and the complexity of network signaling interaction will be increased. At the same time, the response process of the UE is increased, which consumes more power.

Contents of the invention

In view of this, the main purpose of the present invention is to provide a method for determining the number of receiving users in a multimedia broadcast/multicast service, which reduces unnecessary waste of radio interface resources and simplifies the network signaling process.

In order to achieve the above object, the technical solution of the present invention is specifically realized in the following way:

A method for determining the number of receiving users in the multimedia broadcast/multicast service MBMS, the method includes the following steps:

1) During the MBMS session start process, the core network side sends an inquiry identifier to the base station controller BSC/radio network controller RNC, and the inquiry identifier is used to indicate whether the BSC/RNC inquires whether the user equipment UE receives the MBMS session;

2) Before the BSC/RNC establishes radio resources, the BSC/RNC judges whether the inquiry identifier received from the core network side is valid, and if it is valid, asks the UE whether to receive the MBMS session, and determines the receiving UE according to the UE willing to receive the session otherwise, determine the number of receiving UEs according to the fact that all UEs that have activated the MBMS service are willing to receive the session.

Wherein, the step 1) may include:

11) When the session starts, the broadcast/multicast service center BM-SC sets whether the inquiry identifier indicating BSC/RNC is valid according to the nature of the service;

12) The BM-SC sends a session start request message to the serving GPRS support node SGSN through the gateway GPRS support node GGSN, and the session start request message includes the inquiry identifier;

13) After receiving the session start request message sent by the GGSN, the SGSN sends an MBMS session start request message to the BSC/RNC, and the session start request message includes the inquiry identifier.

The step 12) may be: the BM-SC sends a session start request message including the query identifier to the GGSN; after receiving the session start request message, the GGSN sends an MBMS session start request message including the query identifier to the SGSN.

Step 2) The method for judging whether the inquiry identifier received from the core network side is valid may be: obtaining the inquiry identifier from the session start request message, and judging whether the inquiry identifier is valid.

Step 2) The process of the BSC/RNC asking the UE whether to receive the MBMS session may include:

21) The BSC/RNC sends an inquiry request to the UE in the cell that has activated the MBMS service;

22) The UE that agrees to receive the MBMS session returns an inquiry response message to the BSC/RNC.

Step 2) The method of determining the number of receiving UEs according to the UEs willing to receive the session may be: counting the UEs that return the inquiry response message, and determining the number of receiving UEs according to the counted number of UEs. The specific method is as follows: if the BSC/RNC counts all UEs that return query response messages, and the counted number of UEs does not reach the predetermined UE counting threshold, then the counted number of UEs is determined as the number of receiving UEs; In the process of counting the UEs that return query response messages by the RNC, if the number of UEs counted reaches the predetermined UE count threshold value, the BSC/RNC stops receiving the query response messages returned by the UE, and determines the predetermined UE count threshold value is the number of receiving UEs.

Step 2) The process of determining the number of receiving UEs according to the fact that all UEs that have activated the MBMS service are willing to receive the session may include:

23) The BSC/RNC sends a counting request to the UE in the cell that has activated the MBMS service;

24) All UEs that receive the counting request feed back the counting response to the BSC/RNC;

25) The BSC/RNC counts the UEs that feedback the counting response; and determines the number of receiving UEs according to the counted number of UEs.

Described step 25) can be:

If the BSC/RNC counts all feedback counting response UEs, and the counted number of UEs does not reach the predetermined UE counting threshold, then the counted number of UEs is determined as the number of receiving UEs;

If the number of UEs counted reaches the predetermined UE counting threshold during the BSC/RNC counting the UEs that feed back the counting response, the BSC/RNC stops receiving the counting response fed back by the UE, and counts the predetermined UE counting threshold Determine the number of UEs that are receiving.

It can be seen from the above technical solutions that in the method for determining the number of receiving user equipment UEs in the multimedia broadcast/multicast service of the present invention, the MBMS session start request message sent to the BSC/RNC carries an inquiry identifier, and the inquiry identifier It is used to indicate whether the BSC/RNC should ask the UE whether to receive the MBMS session before establishing radio resources. The BSC/RNC determines whether to ask the UE whether to receive the MBMS session when counting according to the identifier. If it is indicated that there is no need to ask the UE whether to receive the MBMS session, the BSC/RNC determines the number of receiving UEs according to the fact that all UEs that have activated the MBMS service are willing to receive the session. In this way, the process of the BSC/RNC asking the UE whether to receive the MBMS session is omitted, thereby simplifying the network signaling process and reducing the waste of radio interface resources. At the same time, the power consumption of the UE can be reduced, and the standby time of the UE can be increased.

Description of drawings

Figure 1 is a schematic diagram of the working principle of MBMS;

Fig. 2 is a schematic structural diagram of a wireless network supporting multicast/broadcast services;

FIG. 3 is a schematic diagram of an MBMS session start flow in the prior art;

FIG. 4 is a flow chart of BSC/RNC performing statistics on receiving UEs;

Fig. 5 is a flow chart of establishing radio resources by BSC/RNC in a preferred embodiment of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and examples.

In the method for determining the number of receiving UEs in the multimedia broadcast/multicast service of the present invention, the message sent by the core network side to the access network includes the relevant identifier, and the access network decides whether to ask the UE whether to receive the MBMS session according to the identifier . If it is indicated that there is no need to ask the UE whether to receive the MBMS session, the BSC/RNC determines the number of receiving UEs according to the fact that all UEs that have activated the MBMS service are willing to receive the session.

The process of sending a weather forecast service in text format to a UE subscribing to the MBMS service will be described in detail below as a preferred embodiment.

In this embodiment, according to the nature of the current MBMS session, the BM-SC decides that when the BSC/RNC counts the number of receiving UEs, it is not necessary for the BSC/RNC to ask the UE whether to receive the MBMS session, so it will instruct the BSC/RNC whether to ask the UE Whether to receive the query flag of the MBMS session is set to invalid.

The session start process of the present embodiment is the same as the prior art MBMS session start process shown in FIG. All the MBMS session start request messages carry the query identifier set to be invalid. The process includes the following steps:

Step 301, the BM-SC sends a session start request message (Session Start Request) to the GGSN stored in the "downstream node list" parameter in its corresponding MBMS bearer context, indicating the transmission to be started, and setting the state attribute of the MBMS bearer context to be "activation". The request provides session attributes such as QoS, MBMS service domain, estimated length of the session, etc., and the message also carries an inquiry flag set to be invalid.

Step 302, after the GGSN receives the session start request message, save the session attribute provided in the message in the MBMS bearer context, set the status attribute of the MBMS bearer context to "activate", and send a session start response message to the BM-SC ( Session Start Response).

Step 303, GGSN sends an MBMS session start request message (MBMS SessionStart Request) to the SGSN stored in the "downstream node list" parameter in its corresponding MBMS bearer context, and the message also carries an invalid query identifier.

Step 304, after the SGSN receives the MBMS session start request message, save the session attribute in the MBMS bearer context, and set the state attribute of the MBMS bearer context as "activation", and send an MBMS session start response message (MBMS Session StartResponse) to the GGSN, The message provides a tunnel termination identifier (TEID) for the bearer plane, which is used for the GGSN to send MBMS data.

Step 305, the SGSN sends a MBMS session start request message (MBMS Session Start Request) to each BSC/RNC connected to the SGSN, the message contains the session attribute, and the message also carries an invalid query identifier .

Step 306, the BSC/RNC judges whether it is in the MBMS service domain, if the BSC/RNC is in the MBMS service domain, then first in the MBMS bearer context, save the session attribute, set the status attribute of the MBMS bearer context to "activate", and then perform the steps 307 ; otherwise, directly execute step 307 .

Step 307, BSC/RNC sends an MBMS session start response message (MBMS Session Start Request) to SGSN.

A BSC/RNC receives multiple MBMS session start request messages, which carry Iu bearer plane parameters, and returns only one MBMS session start response message, which is used to establish an Iu plane bearer to an SGSN.

If the BSC/RNC is in the MBMS service domain, the BSC/RNC includes the TEID in the MBMS session start response message, which is used for the Iu bearer plane used by the SGSN to send MBMS data.

If the BSC/RNC is not in the MBMS service domain, the MBMS session start response message sent to the SGSN indicates that the BSC/RNC is not in the MBMS service domain.

Then, BSC/RNC can establish necessary radio resources for transmitting MBMS data to interested UEs in the MBMS service domain.

When the BSC/RNC receives the MBMS session start message sent by the SGSN, it counts the number of UEs expecting to receive the MBMS session in each cell in the BSC/RNC, so as to decide whether to send MBMS session data in the cell.

Referring to Fig. 5, Fig. 5 is a flow chart of establishing radio resources by BSC/RNC in a preferred embodiment of the present invention. In this embodiment, the BSC/RNC presets a UE counting threshold according to the prior art method for setting the UE counting threshold. The process includes the following steps:

In step 501, the BSC/RNC receives the MBMS session start message sent by the SGSN.

In step 502, the BSC/RNC judges whether the inquiry identifier in the received MBMS session start message is valid, and if valid, executes step 503; otherwise, executes step 504.

In this embodiment, the BM-SC sets the inquiry flag as invalid according to the nature of the service, so this embodiment directly executes step 504 .

Step 503, execute the prior art process, count the UEs that return the inquiry response message, and determine the number of receiving UEs according to the counted number of UEs. Then step 505 is executed.

The existing flow described here is the flow of the BSC/RNC performing statistics on the receiving UE shown in FIG. 4 .

Step 504: Determine the number of receiving UEs according to the fact that all UEs that have activated the MBMS service are willing to receive the session. Specifically include the following steps:

a. The BSC/RNC sends a counting request to the UE that has activated the MBMS service in the cell;

b. All UEs that receive the counting request feed back the counting response to the BSC/RNC;

c. The BSC/RNC counts the UEs that feedback the counting response; and determines the number of receiving UEs according to the counted number of UEs.

If the BSC/RNC counts all feedback counting response UEs, and the counted number of UEs does not reach the predetermined UE counting threshold, then the counted number of UEs is determined as the number of receiving UEs;

If the number of UEs counted reaches the predetermined UE counting threshold during the BSC/RNC counting the UEs that feed back the counting response, the BSC/RNC stops receiving the counting response fed back by the UE, and counts the predetermined UE counting threshold Determine the number of UEs that are receiving.

In step 505, the BSC/RNC determines the transmission mode and establishes radio resource bearers according to the number of UEs expecting to receive the MBMS session.

Same as the prior art, if it is decided to send, the corresponding way of establishing the radio resource bearer is determined according to the number of UEs expecting to receive the MBMS session and other RRM algorithms. When the number of UEs expected to be received is relatively small, that is, the UE counting threshold has not been reached, the point-to-point transmission method is adopted; when the number of UEs is large, that is, the UE counting threshold has been reached, the point-to-multipoint transmission.

The MBMS service mentioned in the present invention refers to the multicast service. Since the multicast service only sends corresponding information to UEs that have subscribed to certain information, the broadcast service sends information to all UEs in the wireless network. Therefore, the multicast service needs to collect statistics on the receiving UEs, while the broadcast service does not need statistics.

It can be seen from the above-mentioned embodiments that for services that do not require UE confirmation of reception, such as text, small pictures, file downloads, and advertisements, after adopting the method for determining the number of receiving UEs in the MBMS of the present invention, the wireless network interface resources are reduced. waste, simplifying the network signaling process. The unnecessary UE response process is avoided, the UE is more power-saving, and the standby time of the UE is increased.

Claims (9)

1. A method for determining the number of receiving users in a multimedia broadcast/multicast service MBMS, characterized in that the method comprises the following steps: 1) During the MBMS session start process, the core network side sends an inquiry identifier to the base station controller BSC/radio network controller RNC, and the inquiry identifier is used to indicate whether the BSC/RNC inquires whether the user equipment UE receives the MBMS session; 2) Before the BSC/RNC establishes radio resources, the BSC/RNC judges whether the inquiry identifier received from the core network side is valid, and if it is valid, asks the UE whether to receive the MBMS session, and determines the receiving UE according to the UE willing to receive the session otherwise, determine the number of receiving UEs according to the fact that all UEs that have activated the MBMS service are willing to receive the session. 2. The method according to claim 1, characterized in that: said step 1) comprises: 11) When the session starts, the broadcast/multicast service center BM-SC sets whether the inquiry identifier indicating BSC/RNC is valid according to the nature of the service; 12) The BM-SC sends a session start request message to the serving GPRS support node SGSN through the gateway GPRS support node GGSN, and the session start request message includes the inquiry identifier; 13) After receiving the session start request message sent by the GGSN, the SGSN sends an MBMS session start request message to the BSC/RNC, and the session start request message includes the inquiry identifier. 3. The method according to claim 2, characterized in that said step 12) is: BM-SC sends a session start request message containing said inquiry identifier to GGSN; after receiving the session start request message, GGSN sends The SGSN sends an MBMS session start request message containing the inquiry identifier. 4. The method according to claim 2, wherein the method for judging whether the inquiry identifier received from the core network side is valid in step 2) is: obtaining the inquiry identifier from the session start request message, and judging the inquiry identifier is it effective. 5. The method according to claim 1, wherein the process of asking the UE whether to receive the MBMS session in step 2) comprises: 21) The BSC/RNC sends an inquiry request to the UE in the cell that has activated the MBMS service; 22) The UE willing to receive the MBMS session returns an inquiry response message to the BSC/RNC. 6. The method according to claim 5, characterized in that, in step 2), the method of determining the number of receiving UEs according to the UEs willing to receive the session is: making statistics on the UEs that return the query response message, and counting the number of UEs according to the statistics The number of determines the number of receiving UEs. 7. The method according to claim 6, characterized in that the method of determining the number of receiving UEs according to the UEs willing to receive the session in step 2) is: if the BSC/RNC counts all the UEs that return the inquiry response message Afterwards, if the counted UE number does not reach the predetermined UE counting threshold value, then the counted UE number is determined as the number of receiving UEs; If the BSC/RNC counts UEs that return query response messages, and the counted UE number reaches the predetermined UE count threshold value, then the BSC/RNC stops receiving the query response messages returned by the UE, and sets the predetermined UE count threshold The limit is determined as the number of receiving UEs. 8. The method according to claim 1, wherein the process of determining the number of receiving UEs according to the fact that all UEs that have activated the MBMS service are willing to receive the session in step 2) includes: 23) The BSC/RNC sends a counting request to the UE in the cell that has activated the MBMS service; 24) All UEs that receive the counting request feed back the counting response to the BSC/RNC; 25) The BSC/RNC counts the UEs that feedback the counting response; and determines the number of receiving UEs according to the counted number of UEs. 9. The method according to claim 8, characterized in that the step 25) is: If the BSC/RNC counts all feedback counting response UEs, and the counted number of UEs does not reach the predetermined UE counting threshold, then the counted number of UEs is determined as the number of receiving UEs; If the number of UEs counted reaches the predetermined UE counting threshold during the BSC/RNC counting the UEs that feed back the counting response, the BSC/RNC stops receiving the counting response fed back by the UE, and counts the predetermined UE counting threshold Determine the number of UEs that are receiving.

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