WO2015065022A1

WO2015065022A1 - Method and device for group communication, having robust mobility

Info

Publication number: WO2015065022A1
Application number: PCT/KR2014/010207
Authority: WO
Inventors: 원성환; 조성연; 구트만에릭
Original assignee: 삼성전자 주식회사
Priority date: 2013-10-28
Filing date: 2014-10-28
Publication date: 2015-05-07

Abstract

The present invention relates to a method and a device for group communication. More particularly, the present invention relates to a method and a device by which a moving terminal can effectively participate in the group communication. A communication method for a base station in a mobile communication system, according to one embodiment of the present invention, can comprise the steps of: receiving, from an MCE, MBMS bearer-related information including a QoS parameter; updating bearer information on the terminal by using the received MBMS bearer-related information; determining a handover of the terminal and transmitting a handover request message, which includes the MBMS bearer information, to a second base station incapable of supporting an MME or MBMS; transmitting a handover command message from the second base station to the terminal; and transmitting MBMS data to the second base station for a pre-set amount of time. According to one embodiment of the present invention, although the terminal moves to a region at which the MBMS is not provided, a group communication service is quickly provided through a PTP-type communication channel such that the terminal can seamlessly receive the group communication service.

Description

Method and apparatus for robust group communication

The present invention relates to a method and apparatus for group communication. More specifically, the present invention relates to a method and apparatus for enabling a mobile terminal to effectively participate in group communication.

Early wireless communication systems were developed to provide voice services while ensuring user activity. Moreover, wireless communication systems are gradually expanding to not only voice but also data services, and have now evolved to provide high-speed data services.

Until now, the development of wireless communication system has been mainly focused on point-to-point (PTP) communication. Here, the point may refer to, for example, a caller and a receiver in case of a call between two users (sender and receiver). As another example, given a situation where a user accesses a website, for example, http://www.amazon.com/, the dots may refer to the user and the Amazon server, respectively.

In recent years, interest in providing a group communication service using a wireless communication system has increased. Group communication may be referred to collectively as a communication that includes various subjects including broadcasting.

The group communication service may be provided using existing PTP type communication. For example, when considering a broadcast, a PTP communication path may be generated between a broadcast provider and a plurality of users who want to listen to the broadcast, so that a plurality of users may receive the services of the broadcast provider. However, the above scheme is very inefficient in terms of resource usage. For example, when multiple users require a lot of data in common or in common, it may be very inefficient in terms of resource use when data that is common to multiple users is repeatedly sent through multiple PTP communication paths.

Accordingly, there is a demand for point-to-multipoint communication in order to efficiently use resources and provide group communication services. For PTM communication, Multimedia Multicast Broadcast Service (MBMS) has been enabled for Long Term Evolution (LTE) systems. The move to provide group communication services through MBMS is actively discussed in the 3rd Generation Partnership Project (3GPP).

SUMMARY OF THE INVENTION An object of the present invention is to provide a method and apparatus for receiving a service without interruption of a mobile station in a group communication service in a wireless communication system in which a group communication service is provided through a multimedia multicast broadcast service (MBMS). The present invention also provides a method and apparatus for allowing a terminal to receive a group communication service without interruption by allowing a group communication service to be provided quickly through a point-to-point communication path even when the terminal moves to an area where an MBMS is not provided. The purpose is to provide.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned above will be clearly understood by those skilled in the art from the following description. Could be.

In the mobile communication system according to an embodiment of the present invention for achieving the above technical problem, the communication method of the base station includes a QoS parameter from a multi-cell / multicast coordination entity (MCE) Receiving information related to a multimedia multicast broadcast service (MBMS) bearer; Updating bearer information for a terminal by using the received MBMS bearer related information; Determining a handover of the terminal and transmitting a handover request message including MBMS bearer information to a mobility management entity (MME) or a second base station that cannot support MBMS; Transmitting a handover command message to the second base station to the terminal; And transferring MBMS data to the second base station for a preset time.

The QoS parameter may include at least one of a QoS Class Identifier (QCI), Guaranteed Bit Rate (GBR) QoS information, and Allocation and Retention Priority (ARP). can do. Further, according to an embodiment, the ARP has a priority level for bearer allocation and maintenance, pre-emption capability (for other bearers), and pre-emption vulnerability (by other bearers). It may include at least one of).

In addition, the base station may be located at the edge of the MBMS service area or MBMS Single Frequency Network (MBSFN) area.

The handover request message may include the QoS parameter, a bearer identifier, a downlink (DL) propagation indication indicator, a transport layer address of an S-GW, and an uplink (UL) packet data unit (PDU: Packet Data). It may include at least one of a Tunnel Endpoint Identifier (TEID) of the S-GW for the unit.

The handover request message may further include an indicator indicating that MBMS bearer related information is included.

The updating of the bearer information may further include receiving a message including information indicating that the terminal is receiving an MBMS service or is interested in an MBMS service.

The transmitting of the MBMS data to the second base station for a predetermined time may further include transmitting data indicating that the MBMS data is stopped from being transmitted to the second base station.

In addition, the step of delivering the MBMS data to the second base station for a predetermined time, from the Group Communication Service Enabler Application Server (GCSE-AS: Group Communication Service Enabler Application Server), stopping the transmission of MBMS data to the second base station Receiving the information displayed on the information indicating the; may further include.

In addition, in a mobile communication system according to an embodiment of the present invention for achieving the above technical problem, the communication method of the terminal, MBMS service to the first base station that receives the MBMS bearer-related information including the QoS parameters from the MCE, Transmitting a message containing information that the receiver is receiving or interested in an MBMS service; Receiving a handover command message from the first base station to a second base station that does not support MBMS according to the handover decision of the first base station; Performing a connection with the second base station; Receiving, by the second base station, an MBMS message received from the first base station from the second base station for a preset time; Transmitting a message including information indicating that MBMS service is unavailable to the GCSE-AS; And establishing a bearer with the second base station.

In addition, the information that the MBMS service is unavailable, the first eNB identifier, the second eNB identifier, the source cell identifier, the target cell identifier, the identifier of the terminal, information indicating that the terminal has moved to a cell that does not support MBMS, one or more MBMS It may include at least one of a service area identifier (SAI), a temporary mobile group identifier (TMGI), and a group communication service identifier (ServiceId).

In addition, the base station according to an embodiment of the present invention for achieving the above technical problem, the communication unit; And receiving Multimedia Multicast Broadcast Service (MBMS) bearer related information including QoS parameters from various cell / multicast coordination entities (MCEs). A hand including MBMS bearer information to update a bearer information for a terminal using MBMS bearer related information, determine handover of the terminal, and provide a mobility management entity (MME) or a second base station that does not support MBMS. And a controller configured to transmit an over request message, transmit a handover command message to the second base station to the terminal, and transmit MBMS data to the second base station for a preset time.

In addition, the terminal according to an embodiment of the present invention for achieving the above technical problem, the communication unit; And transmitting a message including information indicating that the MBMS bearer related information including the QoS parameter from the MCE is received or interested in the MBMS service, and determines the handover decision of the first base station. Accordingly, a handover command message to a second base station that does not support MBMS is received from the first base station, the connection is performed with the second base station, and the second base station is received from the first base station for a preset time. And a controller for receiving an MBMS message from the second base station, transmitting a message including information indicating that MBMS service is unavailable to GCSE-AS, and establishing a bearer with the second base station.

In addition, the communication method of the base station in a mobile communication system according to an embodiment of the present invention for achieving the technical problem, the step of receiving an information request message about the number of terminals receiving the MBMS service from the MCE; Determining the number of terminals receiving the MBMS service; And transmitting information on the number of UEs receiving MBMS service to the MCE.

In addition, the communication method of the terminal in a mobile communication system according to an embodiment of the present invention for achieving the technical problem, determining whether the terminal is located at the edge of the MBMS service area; Transmitting a message including information indicating to the GCSE-AS that the terminal is located at an edge of an MBMS service area; Receiving a keep-alive message from the GCSE-AS; And transmitting and receiving a signal to and from the GCSE-AS through a point to point (PTP) path.

In addition, receiving the keepalive message. The method may further include transmitting a message including information for requesting transmission of the keepalive message to the GCSE-AS.

The determining of whether the terminal is located at the edge of the MBMS service area may include receiving an edge indicator indicating from the base station that the terminal is located at the edge of the MBMS service area.

The determining of whether the terminal is located at the edge of the MBMS service area may include: measuring a reference signal (RS); And comparing the RS with a preset threshold to determine whether the terminal is located at an edge of an MBMS service area.

The method may further include receiving the threshold value from the GCSE-AS or the base station.

According to a communication method and apparatus of a terminal and a base station in the mobile communication system according to the present invention, even if the terminal moves to an area where the MBMS is not provided, the group communication service is quickly provided through a PTP type communication path, thereby allowing the terminal to be seamlessly grouped. It can make communication service available.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned above may be clearly understood by those skilled in the art from the following description. will be.

1 is a diagram illustrating an example of a wireless communication system in which a group communication service is provided through an MBMS.

2 is a flowchart illustrating a process of performing S1 based handover according to an embodiment of the present invention.

3 is a flowchart illustrating a process of performing an X2-based handover according to another embodiment of the present invention.

4 is a flowchart illustrating a process of collecting assistance information for determining switching between a PTP scheme and an MBMS scheme for increasing resource efficiency according to another embodiment of the present invention.

5 is a flowchart for providing a group communication service without interruption to an idle mode UE 100 according to another embodiment of the present invention.

6 is an example of a block diagram of a base station according to an embodiment of the present invention.

7 is an example of a block diagram of a terminal according to an embodiment of the present invention.

8 is an example of a block diagram of a GCSE-AS according to an embodiment of the present invention.

9 is a flowchart illustrating a process of allowing a base station not supporting a new QCI value to properly provide a group communication service according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. At this time, it should be noted that the same components in the accompanying drawings are represented by the same reference numerals as possible. In addition, detailed descriptions of well-known functions and configurations that may blur the gist of the present invention will be omitted. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

Also, in describing the embodiments of the present invention in detail, 3GPP will mainly target a wireless access network, a core network LTE, and an evolved packet core (EPC), but the main points of the present invention are similar. Other communication systems having a technical background may be applied in a slight modification without departing from the scope of the present invention, which may be determined by those skilled in the art.

A wireless communication system in which group communication service is provided through a multimedia multicast broadcast service (MBMS) is composed of four elements. Referring to FIG. 1, a wireless communication system in which a group communication service is provided through an MBMS includes a user equipment (UE) 100, a long term evolution (LTE) 130, an evolved packet core (EPC) 199, and the like. It may include a group communication service assistant application server (GCSE-AS) (200).

The GCSE-AS 200 is an entity in which data of a group communication service is aggregated. If there is uplink (UL) data to be transmitted by the UE 100 participating in the group communication, the data is eventually sent to the GCSE-AS 200 through the LTE 130 and the EPC 199. Downlink (DL) group communication data received by the UE 100 is data transmitted by the GCSE-AS 200 and transmitted through the EPC 199 and the LTE 130.

The UE 100 is connected to the LTE 130 via the Uu 105 interface, which is a wireless interface (other interfaces are wired interfaces in the general case). More precisely, the UE 100 is connected to an evolved Node B (eNB) 110 via a Uu 105 interface.

The LTE 130 has a form in which a plurality of eNBs 110 are intricately intertwined. Several eNBs 110 are connected to each other by an X2 113 interface. Each eNB 110 provides a service to the UE 100 in a specific range, each of which is called coverage. Coverage is limited, so if the user wants to receive voice and / or data services while moving, the UE 100 must establish a wireless connection through the appropriate eNB 110 and Uu 105 interface as it moves.

With some exceptions, the eNB 110 may generally consist of one or more cells. Here, a cell refers to a cell of a general cellular system, and the eNB 110 is a device for managing and controlling the cell. In the present specification, the cell and the eNB 110 may be used for the same meaning. In addition, in describing the embodiments herein, the cell and the eNB 110 may be confused for convenience.

DL group communication user data delivered to the eNB 110 may be delivered to the UE 100 through at least two paths. One is a point-to-point communication path, and the other is a path through an MBMS. In the PTP communication path, DL group communication data passes through the GCSE-AS 200 to the Public Data Network Gateway (P-GW) 160 and the Serving Gateway (S-GW) 150. The path is delivered to the eNB 110 via (the interface order is: SGi 165-> S5 / S8 155-> S1-U 116). The DL group communication user data transmission path through the MBMS includes DL Group communication data passing through the GCSE-AS 200 through a Broadcast Multicast Service Center (BM-SC) 180 and an MBMS Gateway (MBMS GW: MBMS). Gateway (170) is a path passed to the eNB 110 (the interface order is: GC2 (185)-> SGi-mb 178-> M1 (118)).

The UL group communication user data transferred from the UE 100 to the eNB 110 may be delivered to the GCSE-AS 200 through a PTP scheme communication path. That is, the UL group communication user data may be transferred from the eNB 110 to the GCSE-AS 200 via the S-GW 150 and the P-GW 160.

The Policy and Charging Rules Function (PCRF) 190 determines the quality of service (QoS) and billing policies differentiated for each service flow for group communication user data. . The PCRF 190 is connected to the P-GW 160 and the BM-SC 180 through the Gx 163 interface and the Gx2 183 interface, respectively, and the GCSE-AS 200 through the Rx 195 interface. It is connected.

In order to control the transmission of DL group communication user data through the MBMS, MBMS session related information such as multicast channel related resource allocation information and a modulation and coding scheme (MCS) needs to be delivered to the eNB 110. There can be. Information on this can be found in the Multi-cell / multicast Coordination Entity (MCE) 120, the Mobility Management Entity (MME) 140, the MBMS-GW 170, and the BM-SC. At least one of the 180 and the GCSE-AS 200 may be transmitted to the eNB 110. In order to transfer MBMS session related information, an interface connected to the eNB 110 through the GCSE-AS 200, the BM-SC 180, the MBMS-GW 170, the MME 140, and the MCE 120 is connected. Each is defined (see Table 1).

Table 1

Interface name	Connected entity
GC2 (185)	GCSE-AS (200), BM-SC (180)
SGmb (175)	BM-SC (180), MBMS-GW (170)
Sm (173)	MBMS-GW (170), MME (140)
M3 (125)	MME (140), MCE (120)
M2 (112)	MCE 120, eNB 110

As described above, the DL group communication user data delivered to the eNB 110 may be delivered through a PTP scheme communication path and / or a path through the MBMS. At this time, according to an embodiment, if the UE 100 that wants to receive the DL group communication user data and / or the UE 100 that can receive the DL group communication user data is densely located (if MBMS can be provided), the group communication service is provided through the MBMS. May be suitable. In addition, it may be appropriate to provide a group communication service to each UE 100 in a PTP manner in an area where the UE 100 that wants to receive DL group communication user data and / or where the UE 100 that can receive DL group communication user data is scarce. have.

In addition, when the UE 100 moves to an area where MBMS cannot be provided according to an embodiment, it may be necessary to provide a group communication service in a PTP manner. On the contrary, when the UE 100 moves from the area where the MBMS cannot be provided to the area where the MBMS can be provided, the UE 100 may switch from the PTP type group communication service to the group communication service through the MBMS.

As such, the UE 100 may need to operate while switching between the PTP scheme and the MBMS scheme due to resource efficiency and mobility. In this case, the GCSE-AS 200 may determine the conversion.

When switching between the PTP scheme and the MBMS scheme in order to use resources efficiently, it can be said that the area where the UE 100 receives service supports both the PTP scheme and the MBMS scheme. Therefore, there is room for the group communication service to be maintained without interruption during the transition. For example, when switching from the PTP scheme to the MBMS scheme, the UE 100 may receive a group communication service in the PTP scheme until a communication path through the MBMS is prepared.

Even when switching due to mobility, the group communication service can be maintained seamlessly when switching from PTP to MBMS. When moving from a cell supporting only a general PTP scheme to a cell supporting both MBMS scheme and PTP scheme communication, the UE 100 may receive a group communication service in a PTP scheme until a communication path through the MBMS is prepared. In the present specification, a description will be made on the assumption that PTP communication is also provided to a cell supporting MBMS communication, and only PTP communication is provided to a cell not supporting MBMS communication, but is not limited thereto. That is, there may be a cell that supports only MBMS communication and the present invention may be applied to this.

On the other hand, due to mobility, the group communication service may be interrupted when switching from the MBMS method to the PTP method. For example, if the UE 100 moves to a cell in which MBMS is not supported, the UE 100 may no longer be provided with the group communication service provided through the MBMS. In this case, as soon as the UE 100 moves to a cell in which MBMS is not supported, the group communication service is cut off, and the UE 100 may need to request the group communication service from the GCSE-AS 200 again. In this case, the UE 100 may not receive the group communication service until the group communication service is resumed.

On the other hand, group communication services can be used in very important tasks. For example, it can be used by police and firefighters for public safety. In this case, disconnection of the group communication service may cause very undesirable results. Embodiments of the present invention include a method for resolving and mitigating a disconnection phenomenon in a group communication service.

According to an embodiment of the present invention, in the S1 based handover, a disconnection of the group communication service may be alleviated by generating a radio bearer for the group communication service in advance in the target eNB 110b.

Referring to FIG. 2, before starting the S1-based handover, the MCE 120 may plant MBMS bearer related information when generating an MBMS session with the first eNB 110a. In step 210, the MCE 120 may send a message including MBMS bearer related information to the first eNB 110a. The MBMS bearer related information may include a QoS parameter. The QoS parameter may include at least one of a QoS Class Identifier (QCI), Guaranteed Bit Rate (GBR) QoS information, and Allocation and Retention Priority (ARP). . The GBR QoS information may include a GBR and a maximum bit rate (MBR). According to an embodiment, the message may mean at least one of an MBMS SESSION START REQUEST message and an MBMS SESSION UPDATE REQUEST message. On the other hand, according to an embodiment, the ARP may have a priority level for bearer allocation and maintenance, pre-emption capability (for other bearers), and pre-emption vulnerability (by other bearers). It may include at least one of).

According to an embodiment, the MBMS bearer related information delivery through step 210 may be targeted only to the optional first eNB 110a. Delivering MBMS bearer related information to the first eNB (110a) is for generating a radio bearer in advance to the second eNB (110b) that does not support MBMS to deliver MBMS data. Therefore, the MBMS bearer-related information transfer may be targeted only to the first eNB 110a located at the edge of the MBMS service area or MBMS Single Frequency Network (MBSFN) area, for example.

In step 210, the first eNB 110a receiving the message including the MBMS bearer related information may store the received MBMS bearer related information. In operation 215, the first eNB 110a may transmit a response message to the message received through operation 210 to the MCE 120. The response message may mean at least one of an MBMS SESSION START RESPONSE message and an MBMS SESSION UPDATE RESPONSE message.

When the MBMS session is normally generated and the MBMS related wireless channel setup and modification in the first eNB 110a is completed, the UE 100 serviced by the first eNB 110a may receive the service through the MBMS. Thus, as shown by the dotted lines in FIG. 2, the group communication data is transmitted to the UE 100 via the GCSE-S 200, the BM-SC 180, the MBMS-GW 170, and the first eNB 110a. Can be delivered.

In operation 218, the UE 100 receiving the MBMS service may transmit a message including information indicating that the UE is receiving the MBMS service or is interested in the MBMS service. The message may mean an MBMSInterestIndication message or an MBMSCountingResponse message. According to an embodiment, at least one of the messages may include information indicating an interest in the MBMS service for each MBMS session, Temporary Mobile Group Identity (TMGI), and Group Communication Service Identifier (ServiceId). For example, in order to indicate that the MBMS service is interested in each MBMS session, TMGI, and ServiceId, at least one of the messages may include an MBMS session identifier or a bitmap in which each bit represents an MBMS session. Here, ServiceId may be used to identify a group communication service. The ServiceID for identifying the group communication service may mean the same identifier as the ServiceId used in the MBMS service, or, according to an embodiment, may mean a new identifier for group communication only. TMGI is for identifying MBMS bearer service that can be used as a means for providing a service from a user perspective identified by ServiceId.

In operation 220, the first eNB 110a receiving a message indicating that the UE 100 receives the MBMS service or is interested in the MBMS service may update bearer information about the UE 100 that has been stored. In more detail, the first eNB 110a may modify the bearer information for the UE 100 such that the bearer information for the UE 100 may include MBMS bearer related information received from the MCE 120 through step 210. Can be.

Thereafter, as the UE 100 moves, the first eNB 110a may no longer be an eNB suitable for servicing the UE 100. In this case, in step 221, the first eNB 110a may select a second eNB 110b suitable for servicing the UE 100 and decide to handover the UE 100.

In operation 225, the first eNB 110a may send a message including information for requesting handover to the MME 140, for example, a HANDOVER REQUIRED message. In this case, the HANDOVER REQUIRED message may include an information element (IE) for notifying the MME 140 of MBMS bearer related information. The IE may include at least one of a QoS parameter, a bearer identifier, a DL delivery proposal indicator, an MBMS session indicator, an MBMS service area identifier (SAI), a TMGI, and a ServiceId . According to an embodiment, when MBMS bearer related information is included in the message, a new indicator may be included in the MBMS bearer related information to inform MME 140 that the information is MBMS related information. Alternatively, in addition to the method of including a new indicator, a bearer identifier that can be assigned only to the MBMS bearer may be promised so that the MME 140 may know that the bearer indicated by the bearer identifier is an MBMS bearer.

For convenience of description, FIG. 2 depicts a case in which the MME 140 in charge of the first eNB and the

second eNBs

110a and 110b are the same. According to an embodiment, when the MME 140 in charge of the first eNB and the

second eNBs

110a and 110b is different, the MME in charge of the first eNB 110a may be referred to the MME in charge of the second eNB 110b. Forward Relocation Request message can be sent. In this case, the message may include at least one of a QoS parameter, a bearer identifier, an indicator of whether data can be delivered, and a new indicator for informing that the corresponding information is information related to the MBMS.

In addition, according to an embodiment, the forward relocation request message may include information related to an evolved radio access bearer (E-RAB). The bearer for group communication service delivery among the E-RABs may include at least one of MBMS session indicator, MBMS SAI, TMGI, and ServiceId. In more detail, the MME 140 may have mapping information between at least one of the MBMS session indicator, MBMS SAI, TMGI, and ServiceId and E-RAB in advance. The MME 140 uses the at least one of the MBMS session indicator, MBMS SAI, TMGI, and ServiceId received from the first eNB 110a and the mapping information to the MBMS session indicator, MBMS SAI, TMGI. , ServiceId may include at least one information.

In step 230, the MME 140 may send a HANDOVER REQUEST message to the second eNB 110b. The HANDOVER REQUEST message may include MBMS bearer related information. The MBMS bearer-related information may include QoS parameters, bearer identifiers, indicators of whether data can be delivered, a transport layer address of the S-GW 150, and an S-GW for a UL packet data unit (PDU). 150 may include at least one of a tunnel endpoint identifier (TEID). The MME 140 may add the MBMS bearer related information to general PTP type bearer information, and then send the MBMS bearer related information to the second eNB 110b so that the MBMS bearer and the PTP type bearer are not distinguished.

According to an embodiment, the HANDOVER REQUEST message may include E-RAB related information. The bearer for group communication service delivery among the E-RABs may include at least one of MBMS session indicator, MBMS SAI, TMGI, and ServiceId. In more detail, the MME 140 may have in advance mapping information between at least one of the MBMS session indicator, MBMS SAI, TMGI, and ServiceId and the E-RAB. The MME 140 uses the at least one of the MBMS session indicator, MBMS SAI, TMGI, and ServiceId received from the first eNB 110a and the mapping information to the MBMS session indicator, MBMS SAI, TMGI. , ServiceId may include at least one information.

Since data transmission through the MBMS is made from the MBMS GW 170 rather than the S-GW 150, and UL data transmission is not allowed, unlike the general PTP type bearer and the related information, the MBMS bearer related information is obtained from the S-GW ( The transport layer address of 150) and the TEID for the UL PDU may not be needed. In this case, according to an embodiment, the MME 140 may arbitrarily set a transport layer address of the S-GW 150 and a TEID for the UL PDU and transmit the same to the second eNB 110b. Or, using this point, the specific transport layer address and / or the TEID for the UL PDU may refer to the MBMS bearer, so that the second eNB 110b transmits the specific transport layer address and / or the UL PDU TEID for the corresponding bearer. May be aware that it is an MBMS bearer.

In step 235, the second eNB 110b may send a HANDOVER REQUEST ACKNOWLEDGE message to the MME 140. The second eNB 110b may determine whether to accept each bearer having information in the HANDOVER REQUEST message. The HANDOVER REQUEST ACKNOWLEDGE message may include bearer related information including the MBMS bearer accommodated in the second eNB 110b. The MBMS bearer related information may include at least one of a bearer identifier, a QoS parameter, a transport layer address of the second eNB 110b, a TEID for DL PDU, and a TEID / Transport Layer address for UL / DL data to be transmitted from the first eNB 110a. It may include.

According to an embodiment, the HANDOVER REQUEST ACKNOWLEDGE message may include E-RAB related information. The bearer for group communication service delivery among the E-RABs includes at least one of MBMS session indicator, MBMS SAI, TMGI, ServiceId, and TEID / Transport Layer address for UL / DL data to be transmitted from the first eNB 110a. can do. In more detail, the second eNB 110b may receive from the MME 140 E-RAB information including at least one of the MBMS session indicator, MBMS SAI, TMGI, and ServiceId through step 230. The second eNB 110b may include at least one of MBMS session indicator, MBMS SAI, TMGI, and ServiceId as it is in E-RAB related information including at least one of the MBMS session indicator, MBMS SAI, TMGI, and ServiceId received from MME 140. It can carry one piece of information. In addition, the second eNB 110b may additionally include a TEID / Transport Layer address for UL / DL data to be transmitted from the first eNB 110a in the E-RAB related information.

In step 245, the MME 140 may command a handover by sending a HANDOVER COMMAND message to the first eNB 110a. Subsequently, in step 250, the first eNB 110a sends an RRCConnectionReconfiguration message to the UE 100 so that the UE 100 can synchronize with the cell of the second eNB 110b so that the UE 100 can receive service from the second eNB 110b. can do.

According to an embodiment, the HANDOVER COMMAND message may include E-RAB related information. The bearer for group communication service delivery among the E-RABs includes at least one of MBMS session indicator, MBMS SAI, TMGI, ServiceId, and TEID / Transport Layer address for UL / DL data to be transmitted from the first eNB 110a. can do. The information may be received by the MME 140 from the second eNB 110b via step 235, according to an embodiment.

Meanwhile, as shown by a dotted line in FIG. 2, the first eNB 110a receiving the HANDOVER COMMAND message in step 245 may deliver MBMS data to the second eNB 110b using the Transport Layer address and the TEID included in the message. have. According to an embodiment, the data transfer may be delivered from the first eNB (110a) to the second eNB (110b) if the direct transfer of data is possible, otherwise the S-GW ( It may be delivered to the second eNB 110b via 150.

The transmission may be referred to as transferring data received through the MBMS path (MBMS E-RAB) to the PTP path (E-RAB). The mapping between the MBMS E-RAB and the E-RAB may be performed by comparing the MBMS E-RAB information with at least one of the MBMS session indicator, MBMS SAI, TMGI, and ServiceId received in step 245.

UE 255 in step 100 may send a message to a RRCConnectionReconfigurationComplete eNB 2 (110b) in answer to the RRCConnectionReconfiguration message. In this case, UL and DL data may be exchanged between the UE 100 and the second eNB 110b. The UE 100 may receive MBMS data delivered through the GCSE-AS 200, the BM-SC 180, the MBMS GW 170, the first eNB 110a, and the second eNB 110b. According to an embodiment, the first eNB 110a may deliver MBMS data to the second eNB 110b for a specific time. The specific time may be a preset value or a value calculated by considering at least one of time stamp information included in a SYNC layer header of MBMS data and a time of receiving a HANDOVER COMMAND message. If the specific time is too short, the group communication service may be temporarily disconnected before the UE 100 can receive the group communication service through the PTP method (after step 290). On the contrary, if the specific time is too long, MBMS data transfer from the first eNB 100a to the second eNB 100b will occur unnecessarily even though the UE 100 has already been able to receive the group communication service through the PTP scheme. Can be. According to an embodiment, after the specific time, the first eNB 100a may stop the MBMS data transfer and send a packet containing an end marker to the second eNB 100b to inform that the data transfer is complete.

On the other hand, since the MME 140 provided information about the S-GW 150 through step 230, UL data is transmitted to the UE 100, the second eNB 110b, the S-GW 150, and the P-GW ( 160 may be delivered to the GCSE-AS (200).

In operation 260, the UE 100 may send a message including information indicating that the MBMS service is not supported to the GCSE-AS 200 using the UL data path. The message including the information that the MBMS service is not supported includes a first eNB 110a identifier, a second eNB 110b identifier, a source cell identifier, a target cell identifier, a UE 100 identifier, and a UE 100. The information indicating that the mobile station is moved to an unsupported cell may include one or more of one or more MBMS SAI, TMGI, and ServiceId. The message may be, for example, an MBMS Service Unavailable message. As can be seen in this step, ServiceId may be an identifier of the group communication that can be recognized between the UE 100 and the GCSE-AS 200, that is, defined at the application level.

Meanwhile, the second eNB 110b receiving the RRCConnectionReconfigurationComplete message from step 255 may send a HANDOVER NOTIFY message indicating that the handover was successfully performed to the MME 140 in step 265. Although not shown in FIG. 2, the MME 140 subsequently changes the bearer information while the S-GW 150 and / or the S-GW 150 exchanges the P-GW 160 with a Modify Bearer Request / Response message. For example, transport layer address (TEID) can be exchanged.

As described above, in step 260, the GCSE-AS 200 is informed that the UE 100 has moved to an unsuitable cell to receive the MBMS service through a message including information indicating that the MBMS service is not supported, such as an MBMS Service Unavailable message. Could. According to an embodiment, although not shown, in addition, the MME 140 receiving the HANDOVER NOTIFY message through step 265 may send a message indicating that the handover has been made to the S-GW 150. In this case, the message may be a Change Notification message. In this case, the change notification message may contain a target cell identifier. Subsequently, the change notification message may be transmitted from the S-GW 150 to the P-GW 160. In addition, the P-GW 160 may transmit the target cell identifier to the PCRF 190 and / or the GCSE-AS 200.

In operation 270, the GCSE-AS 200 may determine to provide a group communication service to the UE 100 in a PTP manner, and may exchange information with the PCRF 190 for establishing a new bearer and updating an existing bearer. In this case, the GCSE-AS 200 may provide the PCRF 190 with at least one information of MBMS session indicator, MBMS SAI, TMGI, ServiceId, QoS, and group communication service characteristic. The PCRF 190 receiving the information may be reflected in the bearer setup. The above-described group communication service characteristic may include, for example, description of media or flow, and priority, and the GCSE-AS 200 is an interface between the UE 100 and the UE 100 and the GCSE-AS 200. It may be determined through the information delivered through the GC1. Here, the information transmitted through the GC1 may include a profile related to the UE 100.

On the other hand, according to an embodiment, the QoS described above throughout this specification will be described in the future.

The PCRF 190 is sent to the P-GW 160 (step 275);

P-GW 160 to S-GW 150 (step 280);

The S-GW 150 to the MME 140 (step 280);

The MME 140 to the eNB 110b (step 280); And / or

The MME 140 to the UE 100 (step 280).

The information may be different from the QoS parameter to convey.

That is, as described above, the QoS parameter may be referred to as comprehensive information including at least one of QCI, GBR QoS information, and ARP. A more detailed description will be described later, that is, the QoS parameter may be referred to as a standardized specific configuration for the bearer. On the other hand, the QoS delivered in this step 270 may be less specific information than QoS parameters. For example, the ARP may be configured with at least one of detailed parameters such as priority level, pre-emption capability, and pre-emption vulnerability. However, the GCSE-AS 200 may deliver only the priority level to the PCRF 190, and the PCRF 190 may additionally differ from the priority level (for example, MBMS session indicator, MBMS SAI, TMGI, ServiceId, and group communication). The remaining values of the ARP (pre-emption capability, pre-emption vulnerability) may be generated using at least one piece of service characteristic.

On the other hand, PCRF 190 can derive the QoS parameters as follows:

QCI: can be determined by ServiceId and / or group communication service characteristics. Even in the same group communication service, the QCI may be designated differently according to the characteristics of the service. This may be determined by the exchange of information at the application end between the UE 100 and the GCSE-AS 200. For example, a higher priority QCI can be assigned to a bearer used by the UE 100 of a firefighter who has an important position in a group communication service between firefighters. In addition, when recognizing that the group communication service from the ServiceId or the group communication service from the nature of the group communication service, it may be determined as a newly defined QCI for the group communication service. On the other hand, the group communication service personality may include, for example, media or flow description and priority information. According to an embodiment, the priority information may be used for a purpose different from the priority level contained in the QoS (for example, priority information contained in the nature of group communication service is used to determine the priority of the QCI, and the priority level contained in the QoS is the priority of the ARP can be used to determine the level).

Priority level: According to an embodiment, the priority level contained in QoS may be derived as it is or processed. In addition, ServiceId may be considered. When deriving the priority level by processing the priority level contained in the QoS, the mapping between the priority level sent by the GCSE-AS 200 (for each ServiceId) and the priority level derived by the PCRF 190 is provided to the PCRF 190. ) Configuration information may exist.

Pre-emption capability / vulnerability: It may be appropriately set in consideration of the priority level and / or ServiceId contained in QoS.

In operation 275, the PCRF 190 may send an IP-CAN Session Modification message to the P-GW 160. The PCRF 190 sending the IP-CAN Session Modification message to the P-GW 160 may be caused by the message received in step 270. Alternatively, information related to the location of the UE 100 received from the P-GW 160 that the PCRF 190 receives the change notification message may be triggered, and the IP-CAN Session Modification message may be sent to the P-GW 160. You can also send. The IP-CAN Session Modification message may contain at least one of MBMS session indicator, MBMS SAI, TMGI, ServiceId, and QoS parameters. Accordingly, in step 280, the P-GW 160, the S-GW 150, the second eNB 110b, the MME 140, and the UE 100 may establish or update a bearer. The target of bearer establishment will mainly be a dedicated bearer (since a default bearer may already be established). However, in some embodiments, the target of bearer update may be a default bearer or a dedicated bearer. In this case, the Create / Update Bearer Request message that may be used when establishing / updating a bearer may include at least one of an MBMS session indicator, MBMS SAI, TMGI, ServiceId, and QoS parameters. The MME 140 compares the information (at least one of the MBMS session indicator, MBMS SAI, TMGI, ServiceId, and QoS parameters) with E-RAB related information corresponding to the second eNB 110b, and the E-RAB and PCRF. 190 may connect the bearer triggered. At this time, the MME 140 may allocate an appropriate EPS bearer identifier.

In more detail, in step 275, the P-GW 160 receives the MBMS session indicator, the MBMS SAI, TMGI, ServiceId, and QoS parameters from the PCRF 190, wherein the QoS parameters include at least one of QCI, GBR QoS information, and ARP. In this case, at least one of QCI, GBR QoS information, and ARP may have a value specifically assigned for group communication according to the provider network.) Can be. The P-GW 160 may use at least one of the above information to make a bearer decision differently than in the normal case (eg, when a QoS parameter is provided). For example, in the general case, the P-GW 160 may add only a new IP flow to a bearer that satisfies an already existing QoS parameter without creating a new bearer. However, according to the present embodiment, the P-GW 160 may create / update a new bearer because at least one of the MBMS session indicator, MBMS SAI, TMGI, ServiceId information, and QoS parameter is newly delivered. . The P-GW 160 may store at least one of MBMS session indicator, MBMS SAI, TMGI, ServiceId, and QoS parameters in a bearer related context managed by the P-GW 160.

Meanwhile, in operation 280, the P-GW 160 may deliver at least one of MBMS session indicator, MBMS SAI, TMGI, ServiceId, and QoS parameters to the S-GW 150. In this case, the message transmitting the information may be a Create / Update Bearer Request message. The S-GW 150 may store at least one of an MBMS session indicator, MBMS SAI, TMGI, ServiceId information, and QoS parameters in a bearer related context managed by the S-GW 150. The S-GW 150 may deliver at least one of MBMS session indicator, MBMS SAI, TMGI, ServiceId, and QoS parameters to the MME 140. The message delivering the information may be a Create / Update Bearer Request message. The MME 140 may store at least one of an MBMS session indicator, MBMS SAI, TMGI, ServiceId information, and QoS parameters in a bearer related context managed by the MME 140. The MME 140 may deliver at least one of the information to the target eNB (ie, the second eNB) 110b in the S1-based handover process. The delivery can follow step 230.

Subsequently, in step 280, the MME 140 may deliver at least one of MBMS session indicator, MBMS SAI, TMGI, ServiceId, and QoS parameters to the second eNB 110b. The message delivering the information may be an E-RAB SETUP REQUEST message. The second eNB 110b may store at least one of an MBMS session indicator, MBMS SAI, TMGI, ServiceId information, and QoS parameters in a bearer related context managed by the second eNB 110b.

On the other hand, bearers carrying data for group communication services are intermittent (e.g., characteristics of services such as Push To Talk, which may be representative characteristics of group communication services), and data may not be continuously transmitted. It may need to be displayed to reflect a short delay request (e.g., a request based on the use of users responsible for public safety, such as police). In this case, at least one of an MBMS session indicator, MBMS SAI, TMGI, ServiceId information, and QoS parameters that may be delivered to the second eNB 110b via the P-GW 160, the S-GW 150, and the MME 140. One can be used to make an indication that can reflect the above characteristics of the group communication service. For example, at least one of the MBMS session indicator, MBMS SAI, TMGI, and ServiceId information can identify the group communication service itself, so that the characteristics of the group communication service can be reflected. Meanwhile, the QoS parameter may be information reflecting characteristics of the group communication service.

Specific examples of how the QoS parameters can reflect the characteristics of the group communication service are as follows:

Introduction of new QCI values;

Create new indicator.

In this case, each QCI value has a combination of different Resource Type, Priority, Packet Delay Budget, and Packet Error Loss Rate. Therefore, when a new QCI value is introduced, a QCI value having a new combination of Resource Type, Priority, Packet Delay Budget, and Packet Error Loss Rate may be newly specified compared to the previously defined QCI value.

In this case, a new QCI value may be generated for at least one of the following. That is, mission critical Push To Talk voice data, non Mission critical Push To Talk voice data, Mission critical Push To Talk signaling, non Mission critical Push To Talk signaling , Push-to-talk signaling (without mission criticality), bearer for general group communication (which can also be further divided into signaling and user data), mission critical (video) data and public safety bearer (which is also detailed) In this case, new QCI values may be generated for at least one of signaling and user data). According to an embodiment, a Resource Type for a QCI value corresponding to voice data among the new QCI values may correspond to a guaranteed bit rate (GBR). And, the resource type for the QCI value corresponding to the signaling may correspond to non-GBR. Alternatively, in order to express the intermittency of the Push To Talk voice data, a new Resource Type value such as, for example, a bursty GBR or a hybrid GBR may be defined in addition to the existing GBR. It is obvious that other names indicating intermittentity are possible even if they are not necessarily bursty GBR or hybrid GBR). This new Resource Type value (for example, bursty GBR or hybrid GBR) may be designated as a Resource Type of a QCI value corresponding to Push To Talk voice data. Meanwhile, according to an embodiment, even when a bearer having the new Resource Type value may include GBR QoS information. In other words, even when the resource type is not GBR, GBR QoS information may be included. In this case, an entity (eg, a terminal) that is not aware of a new QCI value having a new Resource Type value may map it to an appropriate existing QCI value for GBR.

According to an embodiment, when generating a new indicator, an indicator indicating whether a bearer has at least one of intermittent and short delay requests may be included in a bearer related context.

The second eNB 110b uses at least one of MBMS session indicator, MBMS SAI, TMGI, ServiceId information, and QoS parameters stored in the bearer-related context. You can additionally perform:

At least one of MBMS session indicator, MBMS SAI, TMGI, ServiceId information, and QoS parameters is transmitted to another eNB (e.g., a third eNB) during X2 handover (this operation will be described later with reference to FIG. 3). Can follow 340);

Admission control;

For example, an intermittent bearer can accept the GBR QoS information even if it cannot support it right away.

Determining a corresponding group communication service PTP and PTM change;

Scheduling;

Setting and / or adjusting DRX parameters;

For example, if a relatively very low latency is required (even for the first packet of bursty downlink data / signaling), the DRX parameter can be shortened.

-Setting and / or adjusting inactivity timers.

For example, the second eNB 110b may recognize which group communication service-related bearer the bearer is, and if a lot of bearers for a specific group communication service are generated in the second eNB 110b, the group communication service is performed in the PTM method. May be determined to provide.

In operation 285, the P-GW 160 may transmit an IP-CAN Session Modification message to the PCRF 190. The message sent in step 285 may also include at least one of an MBMS session indicator, MBMS SAI, TMGI, ServiceId, and QoS parameters.

As a result, the UE 100 may receive a group communication service through a PTP scheme. In addition to the group communication data delivery method (transfer MBMS data from the first eNB (110a) to the second eNB (110b) and End Marker transmission for a specific time) described in the section related to the step 255, the group communication data by the method through the step 295 Consider ways to mitigate the loss of.

Some or all of the steps 270 to 290 may be applied to the X2 handover, which will be described later. In addition, it can be used to create and / or modify PTP bearers related to general group communication. In this case, the eNB 110b may be regarded as a general eNB 110.

Meanwhile, according to an embodiment, some of the steps 270 to 290 may be similarly applied when the PTM method is used. For example, in the PTP bearer creation and / or modification, information required for the PCRF 190 to set QoS parameters from the GCSE-AS 200 (MBMS session indicator, MBMS SAI, TMGI, ServiceId, QoS, group communication service characteristics, etc.). Receive at least one piece of information and use it to define the QoS parameters, which are then passed to each of the required communication elements (160, 150, 140, 110b, 100) for MBMS bearer creation and / or modification. It can be applied similarly.

In more detail, in the case of an MBMS bearer, the GCSE-AS 200 may deliver information of at least one of MBMS session indicator, MBMS SAI, TMGI, ServiceId, QoS, and group communication service characteristics to the BM-SC 180. have. The BM-SC 180 may derive QoS parameters from information received from the GCSE-AS 200 similarly to the operation performed by the PCRF 190. The BM-SC 180 then sets the derived new (if creating a new MBMS session) or modified (if updating existing MBMS session) QoS parameters MBMS GW 170, MME 140; It can be delivered to the MCE (120). Meanwhile, in the case of the PTP bearer, the MCE 120 may perform some of the tasks performed by the eNB 110b. That is, since the eNB 110b does not need complicated radio resource management for the MBMS bearer resource on the characteristics (broadcast) of the MBMS bearer, the eNB 110b simply provides data for the MBMS bearer to be released by the MCE 120. The MCE 120 may perform some of the functions that the eNB 110b performs instead of only transmitting the resource. At this time, the MCE 120 may perform at least one of the following operations using the new or modified QoS parameters included in the message MBMS SESSION START REQUEST or MBMS SESSION UPDATE REQUEST delivered through the M3 interface 125. have:

A pre-emption process between MBMS bearers using ARP information can be performed. In this case, the existing MBMS session may be deactivated or the creation of the MBMS session to be created may fail according to the priority level of the new MBMS session.

A new MBMS session creation process can be performed.

MBMS scheduling information process considering the new or modified QoS parameter may be performed (for example, physical multicast channel (PMCH) configuration information and / or to satisfy a condition required by the QoS parameter). Alternatively, the subframe configuration information may be delivered to the eNB 110b.).

Returning to the PTP bearer again, in step 295a, the GCSE-AS 200 sends at least one of an End Marker, a UE 100 identifier, and a source cell identifier to the BM-SC 180 immediately before sending the group communication data sent through the PTP scheme. You can send After the

steps

295b and 295c, the BM-SC 180 sends the MBMS GW 170 to the first eNB 110a at the MBMS GW 170 and at least one of an end marker, a UE 100 identifier, and a source cell identifier. Can be delivered. In operation 295d, the first eNB 110a may transmit an end marker to the second eNB 110b. Thereafter, the first eNB 110a may not deliver MBMS data to the second eNB 110b.

The second eNB 110b preferentially delivers the data received from the first eNB 110a to the UE 100 until it receives the end marker. After the end marker, the second eNB 110b delivers the data delivered from the S-GW 150 to the UE 100.

In the above embodiment, in order to appropriately handle the bearer for the group communication service according to its characteristics (intermittent and / or short latency requirements) in a Radio Access Network (RAN) and / or a Core Network (CN). A method of displaying a new QCI value in a bearer for group communication service has been described.

At this time, if all eNBs 110 in the operator network are upgraded and all eNBs 110 are aware of the new QCI value and know how to handle it, the bearer for group communication service can be handled appropriately. However, considering that there are also a number of eNBs 110 in the operator network, it is difficult to upgrade all at once, and there are also eNBs 110 that are difficult for the operator to directly manage, such as the home eNB 110. Is hard to expect right away.

In this case, the non-upgraded eNB 110b may request to establish a bearer with an unsupported QCI value and / or do not support through at least one of a bearer creation procedure, a bearer modification procedure, and a handover procedure. When a request is made to modify a bearer by value, an appropriate cause may indicate that the bearer establishment and / or modification has failed. An example of Cause value that can be used at this time is Not supported QCI value. If so, the failure to bearer establishment and / or modification is known as P-GW 160 via MME 140 and S-GW 150 and the bearer may be deleted or returned to its previous state.

In this case, a message indicating / suggesting that a new bearer establishment or an existing bearer modification is required for smooth group communication service is delivered to the P-GW 160 via the PCRF 190 or the S-GW 150. Can be. The P-GW 160 receiving the message may decide to establish a new bearer or modify an existing bearer. The P-GW 160 may, for example, send a Create / Update Bearer Request message to request creation of a bearer having a new QCI value. Alternatively, the P-GW 160 may send an Update Bearer Request message requesting to modify the QCI value of the existing bearer to the new QCI value.

The non-upgraded eNB 110 that does not support the new QCI value may inform that the bearer establishment and / or modification has failed with an appropriate cause of failure. In this case, the bearer may be deleted or returned to the previous state, and again, the P-GW 160 may request bearer establishment / modification. According to an embodiment, this may continue to occur while the UE 100 is serviced by the eNB 110 which is not upgraded.

The above-described situation may lead to signaling waste and group communication service failure. Thus, it is necessary to be known as P-GW 160 and / or PCRF 190 that the eNB 110 does not support the new QCI value.

According to the present embodiment, the eNB 110 serving the UE 100 to the P-GW 160 and / or the PCRF 190 may recognize that the new QCI value is not supported. Further, a bearer having a (suboptimal) QCI value suitable for the group communication service may be established, or an existing bearer may be modified to have a (suboptimal) QCI value suitable for the group communication service.

Referring to FIG. 9, in step 910, the eNB 110 may inform the MME 140 that it does not support a new QCI value. In operation 920, the MME 140 may inform the S-GW 150 that the eNB 110 does not support the corresponding QCI value. Thereafter, the S-GW 150 may inform the P-GW 160 that the eNB 110 does not support the corresponding QCI value.

When the MME 140 recognizes that the eNB 110 does not support the corresponding QCI value from the step 910, it notifies the S-GW 150 that the eNB 110 does not support the corresponding QCI value in the step 920. The available method may correspond to at least one of the following:

Inserting an appropriate Cause (eg, Denied in RAT, Not supported QCI value) in at least one message of Create Bearer Response, Update Bearer Response and Modify Bearer Response; And

Insert an indicator indicating that the eNB 110 does not support the corresponding QCI value.

Meanwhile, in step 920, the S-GW 150 uses the P-P using at least one of the methods in which the MME 140 notifies the S-GW 150 that the eNB 110 does not support the corresponding QCI value. It will be apparent that the GW 150 can be used to inform the eNB 110 that the QCI value is not supported.

In step 930, the P-GW 160 may exchange information about the QoS parameters with the PCRF 190. Accordingly, at least one of the PCRF 190 and the P-GW 160 may know that the eNB 110 does not support the corresponding QCI value. Subsequently, when making a decision about bearer creation and modification or sending QoS parameters required for the determination, considering that the eNB 110 does not support the corresponding QCI, group communication among the QCI values supported by the eNB 110 is performed. You can specify the appropriate QCI value for your service.

Meanwhile, according to an embodiment, the message delivered in step 920 may include an identifier (ECGI) of a cell in the eNB 110 that serves the UE 100. Thus, if there is ECGI configuration information in the P-GW 160 and / or PCRF 190, then in step 940 the P-GW 160 and / or PCRF 190 contains the message transmitted in step 920. By looking at the ECGI, the eNB 110 can infer information about whether or not the corresponding QCI is supported.

Meanwhile, according to an embodiment, it is not known to the P-GW 160 whether the eNB 110 supports the corresponding QCI value through step 920, and ECGI setting information is provided to the P-GW 160 and / or the PCRF 190. It may not be. In this case, in step 950, information about whether the eNB 110 supports the corresponding QCI value may be known to the P-GW 160 and / or the PCRF 190 in the bearer creation / modification process.

In more detail, one method is receiving information on whether the eNB 110 supports the corresponding QCI value through the MME 140 (step 950-a), and another method is GCSE-. Receiving information on whether the eNB 110 supports the corresponding QCI value through the AS (200) (step 950-b).

That is, in step 950-a, the MME 140 may issue a command to bearer resource modification to the S-GW 150 / P-GW 160. The message used at this time may be, for example, a Bearer Resource Command message. In this case, the message may include an indicator indicating that the eNB 110 does not support the corresponding QCI value. According to an embodiment, the MME 140 may store the Cause value received in step 910 to recognize that the eNB 110 does not support the corresponding QCI value, and set up S1 between the eNB 110 and the MME 140 in advance. In the process, the eNB 110 may have received information on whether the corresponding QCI value is supported.

In step 950-b, the GCSE-AS 200 receives the request for bearer establishment / modification from the UE 100 or recognizes the need for bearer establishment / modification by itself, and the eNB 110 supports the corresponding QCI value. It can be delivered to the P-GW 160 including an indicator indicating not to. In this case, according to an embodiment, the indicator may be delivered through the PCRF 190.

According to another embodiment of the present invention, in the case of X2-based handover, a disconnection phenomenon of the group communication service may be alleviated by generating a radio bearer for the group communication service in advance in the target eNB 110b.

Referring to FIG. 3, before starting the X2-based handover, the MCE 120 may plant MBMS bearer related information when the MBMS session is generated to the first eNB 110a. In step 310, the MCE 120 may send a message including MBMS bearer related information to the first eNB 110a. The MBMS bearer related information may include a QoS parameter. Detailed description of the QoS parameters has been described above and will be omitted. The message may mean at least one of an MBMS SESSION START REQUEST message and an MBMS SESSION UPDATE REQUEST message.

According to an embodiment, the delivery of MBMS bearer related information through step 310 may be targeted only to the optional first eNB 110a. The transfer of MBMS bearer related information to the first eNB 110a is for generating a radio bearer in advance to the first eNB 110b that does not support the MBMS and delivering MBMS data. Therefore, the MBMS bearer related information transfer may be targeted only to the first eNB 110a located at the edge of the MBMS service area or MBSFN area, for example.

In step 310, the first eNB 110a receiving the message including the MBMS bearer related information may store the received MBMS bearer related information. In operation 315, the first eNB 110a may transmit a response message to the message received through operation 310 to the MCE 120. The response message may mean at least one of an MBMS SESSION START RESPONSE message and an MBMS SESSION UPDATE RESPONSE message.

When the MBMS session is normally generated and the MBMS related wireless channel setup and modification in the first eNB 110a is completed, the UE 100 serviced by the first eNB 110a may receive the service through the MBMS. In this case, as shown by a dotted line in FIG. 3, the group communication data is transmitted to the UE 100 via the GCSE-AS 200, the BM-SC 180, the MBMS-GW 170, and the first eNB 110a. Delivered.

In operation 318, the UE 100 receiving the MBMS service may send a message including information indicating that the UE is receiving the MBMS service or is interested in the MBMS service to the first eNB 110a. The message may mean an MBMSInterestIndication message or an MBMSCountingResponse message.

In operation 320, the first eNB 110a receiving a message indicating that the UE 100 receives the MBMS service or is interested in the MBMS service may update bearer information about the UE 100 that has been stored. In more detail, the first eNB 110a may modify the bearer information for the UE 100 such that the bearer information for the UE 100 may include MBMS bearer related information received from the MCE 120 through step 310. Can be.

Meanwhile, the first eNB and the

second eNBs

110a and 110b may share information on which MBMS service they support. The information sharing may be achieved by the first eNB 110a and the second eNB 110b exchanging the Served Cell Information IE including the TMGI in step 325.

Thereafter, as the UE 100 moves, the first eNB 110a may no longer be an eNB suitable for servicing the UE 100. In this case, the first eNB 110a may select a second eNB 110b suitable for servicing the UE 100 and decide to handover the UE 100.

In operation 340, the first eNB 110a may send a message including information for requesting handover to the second eNB 110b, for example, a HANDOVER REQUEST message. In this case, the HANDOVER REQUEST message may include an IE for notifying MBMS bearer related information. The IE may include at least one of a QoS parameter, a bearer identifier, a DL transfer proposal indicator, a transport layer address of the S-GW 150, and a TEID of the S-GW 150 for the UL PDU. According to an embodiment, when MBMS bearer related information is included in the message, a new indicator may be included in the MBMS bearer related information to inform the second eNB 110b that the information is information related to MBMS. Alternatively, in addition to the method of including a new indicator, a bearer identifier that can be assigned only to the MBMS bearer may be promised so that the second eNB 110b may know that the bearer indicated by the bearer identifier is an MBMS bearer.

In step 340, the first eNB 110a informs the MBMS bearer related information when the MB100 bearer is handed over to the second eNB 110b in which the UE 100 is being serviced. Can be passed. The delivery condition may likewise apply to step 225.

Since data transmission through the MBMS is made from the MBMS GW 170 rather than the S-GW 150, and UL data transmission is not allowed, unlike the general PTP type bearer and the related information, the MBMS bearer related information is obtained from the S-GW ( The transport layer address of 150) and the TEID for the UL PDU may not be needed. In this case, according to an embodiment, the first eNB 110a may arbitrarily set the transport layer address of the S-GW 150 and the TEID for the UL PDU and transmit the same to the second eNB 110b. Or, using this point, the specific transport layer address and / or the TEID for the UL PDU may refer to the MBMS bearer, so that the second eNB 110b transmits the specific transport layer address and / or the UL PDU TEID for the corresponding bearer. May be aware that it is an MBMS bearer.

According to an embodiment, the HANDOVER REQUEST message may include E-RAB related information. The bearer for group communication service delivery among the E-RABs may include at least one of MBMS session indicator, MBMS SAI, TMGI, and ServiceId. Since the description thereof has been described above with reference to FIG. 2, a detailed description thereof will be omitted.

In operation 345, the second eNB 110b may send a HANDOVER REQUEST ACKNOWLEDGE message to the first eNB 110a. The second eNB 110b may determine whether to accept each bearer having information in the HANDOVER REQUEST message. The HANDOVER REQUEST ACKNOWLEDGE message may include bearer related information including the MBMS bearer accommodated in the second eNB 110b. The MBMS bearer related information may include at least one of a bearer identifier, a QoS parameter, and a TEID / Transport Layer address for UL / DL data to be transmitted from the first eNB 110a.

According to an embodiment, the HANDOVER REQUEST ACKNOWLEDGE message may include E-RAB related information. The bearer for group communication service delivery among the E-RABs includes at least one of MBMS session indicator, MBMS SAI, TMGI, ServiceId, and TEID / Transport Layer address for UL / DL data to be transmitted from the first eNB 110a. can do. In more detail, the second eNB 110b may receive E-RAB information including at least one of the MBMS session indicator, MBMS SAI, TMGI, and ServiceId from the first eNB 110a through step 340. have. The second eNB 110b is an MBMS session indicator, MBMS SAI, TMGI, ServiceId as it is in E-RAB related information including at least one of the MBMS session indicator, MBMS SAI, TMGI, and ServiceId received from the first eNB 110a. At least one of the information can be carried. In addition, the second eNB 110b may additionally include a TEID / Transport Layer address for UL / DL data to be transmitted from the first eNB 110a in the E-RAB related information.

Subsequently, in step 350, the first eNB 110a sends an RRCConnectionReconfiguration message to the UE 100 so that the UE 100 can synchronize with the cell of the second eNB 110b so that the UE 100 can receive service from the second eNB 110b. can do.

Meanwhile, as shown by a dotted line in FIG. 3, the first eNB 110a receiving the HANDOVER REQUEST ACKNOWLEDGE message in step 345 transmits MBMS data to the second eNB 110b using the transport layer address and the TEID included in the message. Can be.

In step 355 UE 100 may send a message to the RRCConnectionReconfigurationComplete eNB 2 (110b) in answer to the RRCConnectionReconfiguration message. In this case, UL and DL data may be exchanged between the UE 100 and the second eNB 110b. In addition, the UE 100 may receive MBMS data transmitted through the GCSE-AS 200, the BM-SC 180, the MBMS GW 170, the first eNB 110a, and the second eNB 110b. According to an embodiment, the first eNB 110a may deliver MBMS data to the second eNB 110b for a specific time. The specific time may be a preset value or a value calculated in consideration of at least one of time stamp information included in a SYNC layer header of MBMS data and a time of receiving a HANDOVER REQUEST ACKNOWLEDGE message. If the specific time is too short, the group communication service may be temporarily disconnected before the UE 100 can receive the group communication service through the PTP method (after step 390). On the contrary, if the specific time is too long, MBMS data transfer from the first eNB 100a to the second eNB 100b will occur unnecessarily even though the UE 100 has already been able to receive the group communication service through the PTP scheme. Can be. According to an embodiment, after the specific time, the first eNB 100a may stop the MBMS data transfer and send a packet containing an end marker to the second eNB 100b to inform that the data transfer is complete.

Meanwhile, since the first eNB 110a provides the second eNB 110b with information about the S-GW 150 through step 340, UL data is transmitted to the UE 100, the second eNB 110b, and the S-. It may be delivered to the GCSE-AS 200 via the GW 150 and the P-GW 160.

In step 360, the UE 100 may send a message including information indicating that the MBMS service is not supported to the GCSE-AS 200 using the UL data path. The message including the information that the MBMS service is not supported includes a first eNB 110a identifier, a second eNB 110b identifier, a source cell identifier, a target cell identifier, a UE 100 identifier, and a UE 100. The information indicating that the mobile station is moved to an unsupported cell may include one or more of one or more MBMS SAI, TMGI, and ServiceId. The message may be, for example, an MBMS Service Unavailable message.

Meanwhile, the second eNB 110b receiving the RRCConnectionReconfigurationComplete message from step 355 may send a PATH SWITCH REQUEST message indicating that the handover was successfully performed to the MME 140 in step 365. The message may contain MBMS bearer related information. The MBMS bearer related information may include at least one of a bearer identifier, a transport layer address of the second eNB 110b, a TEID for DL PDU, and an indicator indicating that the bearer is an MBMS bearer. Instead of the method of notifying the bearer directly through the indicator indicating that it is an MBMS bearer, an indirect indication method using the aforementioned bearer identifier, TEID, and / or transport layer address may also be applied.

Meanwhile, according to an embodiment, the MME 140 may not have previously recognized the MBMS bearer related information contained in the PATH SWITCH REQUEST message. If the existing MME 140, the bearer may include information indicating that the bearer is unacceptable in the PATH SWITCH REQUEST ACKNOWLEDGE message. For example, the identifier of the MBMS bearer may be sent to the E-RAB To Be Released List IE. However, if the MME 140 recognizes in advance that the second eNB 110b is located just outside an arbitrary MBSFN Area boundary and sets it, the MMS 140 may accommodate the MBMS bearer even if it is not distinguished from the general PTP bearer. To this end, location information of the second eNB 110b may be set in advance in the MME 140 through a device such as an OAM. If the MME 140 and the second eNB (110b) can recognize each other that the bearer is an MBMS bearer (including an indicator indicating that the bearer is an MBMS bearer, a contracted bearer identifier, TEID, and / and transport layer address Indirect instruction method using the), the location information setting of the second eNB (110b) via the device such as OAM in advance in the MME 140 is not necessarily required.

As described above, in step 360, the GCSE-AS 200 is informed that the UE 100 has moved to an inappropriate cell to receive the MBMS service through a message including information indicating that the MBMS service is not supported, such as an MBMS Service Unavailable message. Could. According to an embodiment, although not shown, in addition, the MME 140 receiving the PATH SWITCH REQUEST message through step 365 may send a message indicating that the handover has been made to the S-GW 150. In this case, the message may be a Change Notification message. In this case, the change notification message may contain a target cell identifier. Subsequently, the change notification message may be transmitted from the S-GW 150 to the P-GW 160. In addition, the P-GW 160 may transmit the target cell identifier to the PCRF 190 and / or the GCSE-AS 200.

Although not shown in FIG. 3, the MME 140 subsequently changes the bearer information while the S-GW 150 and / or the S-GW 150 exchanges the P-GW 160 with a Modify Bearer Request / Response message. For example, a transport layer address (TEID) may be exchanged.

In step 370, the GCSE-AS 200 may determine to provide the group communication service to the UE 100 in a PTP manner, and may exchange information with the PCRF 190 for establishing a new bearer and updating an existing bearer. In this case, the GCSE-AS 200 may provide the PCRF 190 with at least one information of TMGI, ServiceId, and QoS.

In step 375, the PCRF 190 may send an IP-CAN Session Modification message to the P-GW 160. The PCRF 190 sending the IP-CAN Session Modification message to the P-GW 160 may be caused by the message received in step 370. Alternatively, information related to the location of the UE 100 received from the P-GW 160 that the PCRF 190 receives the change notification message may be triggered, and the IP-CAN Session Modification message may be sent to the P-GW 160. You can also send. This IP-CAN Session Modification message may contain QoS parameters. Accordingly, the P-GW 160, the S-GW 150, the second eNB 110b, the MME 140, and the UE 100 may establish or update a bearer in operation 380. In operation 385, the P-GW 160 may transmit an IP-CAN Session Modification message to the PCRF 190. The message sent in step 385 may also include a QoS parameter.

As a result, the UE 100 may receive a group communication service through a PTP scheme. In addition to the group communication data delivery method (transferring MBMS data from the first eNB 110a to the second eNB 110b and transmitting End Marker for a specific time) described in the part related to the step 355, the group communication data by the method of step 395. Consider ways to mitigate the loss of.

In step 395a, the GCSE-AS 200 may send at least one of an end marker, a UE 100 identifier, and a source cell identifier to the BM-SC 180 immediately before sending the group communication data sent through the PTP scheme. After the

steps

395b and 395c, the BM-SC 180 transmits at least one of an end marker, a UE 100 identifier, and a source cell identifier to the MBMS GW 170 and the first eNB 110a at the MBMS GW 170. Can be delivered. In operation 395d, the first eNB 110a may transmit an end marker to the second eNB 110b. Thereafter, the first eNB 110a may not deliver MBMS data to the second eNB 110b.

According to another embodiment of the present invention, by counting the number of the UE (100) that is actually being serviced for the bearer and delivers it to the GCSE-AS 200, the GCSE-AS 200 between the PTP scheme and MBMS scheme You can make a transition decision.

Referring to FIG. 4, in step 400, the MCE 120 may send an MBMS SERVICE COUNITING REQUEST message to the eNB 110. The message may include a TMGI to indicate which service 100 the UE 100 wants to know about. According to an embodiment, the step 400 may be based on a request that the MCE 120 receives from another entity (eg, GCSE-AS 200, BM-SC 180, etc.) directly or indirectly through other entities. It may be triggered.

In operation 410, the eNB 110 and the UE 100 may examine whether the UE 100 receives the MBMS service by exchanging an MBMSCountingRequest message and an MBMSCountingResponse message.

In step 420, the eNB 110 may send a result of checking the number of UEs 100 serviced for the TMGI requested to the MCE 120.

Thereafter, in step 430, the MCE 120 may send all or part of the information included in the MBMS SERVICE COUNTING RESULT REPORT message received from the eNB 110 to the GCSE-AS 200 in step 420. The information may be transferred directly through a new interface between the MCE 120 and the GCSE-AS 200, and the MCE 120-MME 140-MBMS GW 170-BM-SC 180-GCSE- It may be delivered via a path via the AS 200. In the latter case, counting result information for each TMGI may be delivered to the GCSE-AS 200 through a newly defined GC2 185 interface through group communication. The GCSE-AS 200 receiving the information may make a decision about switching between the PTP scheme and the MBMS scheme. For example, the GCSE-AS 200 switches to the MBMS method when there are a lot of UEs 100 to be serviced / received for the corresponding TMGI (if the UE 100 is serviced by the PTP method) / maintenance (if If the UE 100 was being serviced by the MBMS method). In addition, the GCSE-AS 200 switches to the PTP method when there are few UEs 100 to receive / receive service for the corresponding TMGI (if the UE 100 is being serviced by the MBMS method) / maintenance (if UEs). If 100 is being serviced in a PTP fashion). The method of switching to delivering the service by the PTP method may follow some or all of the above-described step 270 to step 290.

In addition to the above-described method, the GCSE-AS 200 needs information for determining the switching between the PTP scheme and the MBMS scheme through a GC1 (which may be an interface between the GCSE-AS 200 and the UE 100 and an application level) message. Can be obtained. In this case, the GCSE-AS 200 may inform the UE 100 that it wants to check how the service is provided in the GC1 message. Accordingly, the UE 100 may notify the GCSE-AS 200 whether it is receiving a service using the PTP method or MBMS method (after switching to the connected mode if it is in the idle mode). Based on this, the GCSE-AS 200 may make a decision about switching between the PTP scheme and the MBMS scheme.

5 is a flowchart for providing a group communication service to the idle mode UE 100 without interruption according to another embodiment of the present invention.

According to another embodiment of the present invention, an indicator is sent to the UE 100 receiving MBMS service at the edge of the MBSFN area and / or MBMS service area, and the UE 100 decides itself to change to the connected mode. You can do that. Meanwhile, if the present embodiment is applied to the UE 100 in the connected mode, the present embodiment may be used to preserve service continuity of the UE 100 located at the edge of the MBSFN area and / or the MBMS service area.

Referring to FIG. 5, in step 500, the eNB 110 may send an edge indicator to the UE 100. According to an embodiment, the eNB 110 sending the edge indicator may be the eNB 110 located at the edge of the MBSFN area and / or MBMS service area. According to an embodiment, the edge indicator may be delivered through BCCH or MCCH. In this case, the edge indicator may include at least one of an indicator indicating that the corresponding cell / eNB 110 is located at an edge, TMGI, ServiceId, MBMS session identifier, and one or more MBMS SAIs.

Alternatively, according to an embodiment, the UE 100 may independently determine that the UE 100 is at the edge through the measurement result. For example, the UE 100 may determine whether it is at the edge by comparing at least one parameter of the measurement result with a specific threshold. In this case, the threshold on which the determination is based may be a value received from the GCSE-AS 200, the eNB 110, and / or the EPC 199. For example, the UE 100 may receive a threshold through a GC1 message, an RRC, a SystemInformationBlock, or a NAS message.

In some embodiments, the measurement result may mean a result of measuring a reference signal (RS). Examples of the reference signal include channel state information (CSI) RS (CSI-RS), cell-specific (Cell-specific) RS (CRS), and the like. The UE 100 may determine whether it is at the edge by comparing the measurement result with a threshold.

In addition, in relation to the threshold, according to an embodiment, the eNB 100 or the EPC 199 may be directly or from at least one entity (eg, BMSC, MBMS-GW, MCE, P-) from the GCSE-AS 200. GW, S-GW, MME) may receive a threshold value. In addition, the eNB 100 or the EPC 199 may transmit the received threshold value to the UE 100. Although not shown at this time, the threshold value may be transferred from the GCSE-AS 200 to the eNB 100 or the EPC 199 via the MCE 120, the MBMS-GW 170, or the BM-SC 180.

In operation 510, the UE 100 may switch to the connected mode. At this time, an RRCConnectionRequest message can be sent. Established because (EstablishmentCause) of the message may choose to set a new one because associated with mo-Signalling, mo-Data, delayTolerantAccess, highPriorityAccess, MBMS. Furthermore, the UE 100 may trigger a service request or bearer resource update process.

The UE 100 in the connected mode or the UE 100 in the originally connected mode (in the case of the UE in the originally connected mode, the step 510 may be omitted) may provide service continuity to the GCSE-AS 200. Action for and / or trigger for receiving a keep-alive message. The trigger can be made by sending a GC1 message to the GCSE-AS 200.

In more detail, in step 520, the UE 100 includes the eNB 110 identifier, the cell identifier, an indicator indicating that it has left the corresponding MBSFN region and / or MBMS service region and / or an edge indicator to the GCSE-AS 200. At least one of some / all of the information may be sent. Meanwhile, even if the UE 100 sends only the eNB 110 identifier or the cell identifier to the GCSE-AS 200 according to the exemplary embodiment, if the eNB 110 related location information is previously set in the GCSE-AS 200, the UE 100 may be determined. It may not be necessary to inform the GCSE-AS 200 that it is an edge of the MBSFN area and / or MBMS service area. As such, the GCSE-AS 200 may recognize that the UE 100 is located at the edge of the MBSFN area and / or MBMS service area.

According to an embodiment, in addition to the method in which the GCSE-AS 200 recognizes that the UE 100 is located at the edge of the MBSFN region and / or MBMS service region through the edge indicator sent in step 520, the GCSE-AS 200 ) May receive cell information from the EPC 199 serving the UE 100. In more detail, although not shown, the P-GW 160 may receive a Change Notification message through the MME 140 and the S-GW 150. In addition, the P-GW 160 may directly transfer the cell information included in the change notification to the GCSE-AS 200 or the GCSE-AS 200 through the PCRF 190.

In this case, if the UE 100 stays at the edge of the MBSFN area and / or MBMS service area for a long time, the UE 100 may change between idle mode and connected mode unnecessarily. Therefore, in order to prevent this, in step 530, the GCSE-AS 200 may send a keep-alive message to the UE 100 located at the edge at an appropriate period. Depending on the embodiment, the suitable period may need to be shorter than the UE inactivity timer.

In addition to the operation of sending a keep-alive message at an appropriate period, the GCSE-AS 200 may transmit and receive the corresponding group communication data through the PTP path to maintain service continuity. In this case, even if it is impossible to transmit / receive group communication data through the PTM path, the UE 100 may receive the group communication service through the PTP path. The eNB that is a target when generating or modifying a PTP path may be an eNB including a cell in which the UE 100 is serviced through an MBMS path, or may be another eNB. The other eNB may be, for example, an eNB outside the MBSFN area and / or the MBMS service area that the UE 100 was serviced / received. Since a detailed description thereof has been described with reference to FIGS. 2 and 3, a detailed description thereof will be omitted. For example, some or all of the above steps 270 to 290 may be followed.

Referring to FIG. 6, a base station according to an embodiment of the present invention may include a communication unit 620 and a control unit 610. The controller 610 of the base station controls the base station to perform any one of the above-described embodiments. For example, the controller 610 receives MBMS bearer related information including QoS parameters from an MCE, updates bearer information for a terminal using the received MBMS bearer related information, and performs handover of the terminal. Determine, transmit a handover request message including MBMS bearer information to a second base station that does not support MME or MBMS, send a handover command message to the second base station to the terminal, and send an MBMS to the second base station The data may be controlled to be delivered for a preset time.

In addition, the communication unit 620 of the base station transmits and receives a signal in accordance with any one of the above-described embodiments. For example, the communication unit 620 may receive MBMS bearer related information including QoS parameters from the MCE, and transmit MBMS data to the second base station for a preset time.

Referring to FIG. 7, the terminal according to an embodiment of the present invention may include a communication unit 720 and a control unit 710. The controller 710 of the terminal controls the terminal to perform any one of the above-described embodiments. For example, the control unit 710 transmits a message including information indicating that the MBMS service is received or is interested in the MBMS service to the first base station that has received the MBMS bearer related information including the QoS parameter from the MCE, In response to the handover decision of the first base station, a handover command message to the second base station that does not support MBMS is received from the first base station, the connection is performed with the second base station, and the second base station is previously determined. Receive the MBMS message received from the first base station from the second base station for a set time, transmit a message including information that MBMS service is unavailable to GCSE-AS, and establish a bearer with the second base station can do.

In addition, the communication unit 720 of the terminal transmits and receives a signal in accordance with any one of the above-described embodiments. For example, the communication unit 720 may transmit a message including information indicating that the first base station receives or is interested in the MBMS service, and may receive MBSM data through the first base station and the second base station. .

The GCSE-AS according to an embodiment of the present invention may include a communication unit 820 and a control unit 810. The controller 810 of the GCSE-AS controls the GCSE-AS to perform the operation of any of the above-described embodiments. For example, the controller 810 may receive a message including information indicating that the MBMS service is not available from the terminal, and control to provide the PTP service between the second base station and the terminal accordingly. Alternatively, the controller 810 may receive an edge indicator indicating that the terminal is located at the edge of the MBMS service area from the terminal, and may control to transmit a keep-alive message to the terminal. In addition, the controller may control to switch between the PTP scheme and the MBMS scheme according to the information on the number of terminals receiving the MBMS service from the MCE.

In addition, the communication unit 820 of the GCSE-AS transmits and receives a signal according to any one of the above-described embodiments. For example, the communication unit 820 may receive a message including information indicating that the MBMS service is not available from the terminal, or receive an edge indicator indicating that the terminal is located at the edge of the MBMS service area from the terminal. In addition, a keep-alive message may be transmitted to the terminal. In addition, the communication unit 820 may receive information about the number of terminals receiving MBMS service from the MCE.

In the above embodiments, all steps and messages may optionally be subject to execution or subject to omission. In addition, in each embodiment, the steps need not necessarily occur in order and may be reversed. Message delivery doesn't necessarily have to happen in order, but can be reversed.

On the other hand, the embodiments of the present invention disclosed in the specification and drawings are merely presented specific examples to easily explain the technical contents of the present invention and help the understanding of the present invention, and are not intended to limit the scope of the present invention. That is, it will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention can be implemented.

Accordingly, the above detailed description should not be construed as limiting in all aspects and should be considered as illustrative. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

Claims

In a communication method of a group communication service enabler application server (GCSE-AS) in a mobile communication system,

Receiving information from the terminal that the multimedia multicast broadcast service (MBMS) including the group communication service identifier is not supported; And

If bearer update of the terminal is required, transmitting information necessary for bearer update to a policy and charging rules function (PCRF) or a broadcast multicast service center (BM-SC);

GCSE-AS communication method comprising a.
The method of claim 1, wherein the information required for bearer update is

And at least one of a group communication service identifier, a group communication service personality, and a priority level.
According to claim 1,

Determining a group communication service identifier and a priority level to be transmitted to the PCRF or the BM-SC using the group communication service identifier received from the terminal;

Communication method of the GCSE-AS further comprises.
In the communication method of the policy and charging rules function (PCRF) in a mobile communication system,

Receiving information necessary for bearer update from a group communication service enabler application server (GCSE-AS); And

Updating a bearer configuration by using the received bearer update information;

PCRF communication method comprising a.
The method of claim 4, wherein the information required for bearer update is

And at least one of a group communication service identifier, a group communication service personality, and a priority level.
The method of claim 4, wherein

Determining at least one of a QoS Class Identifier (QCI), a priority level, pre-emption capability, and pre-emption vulnerability;

Communication method of PCRF characterized in that it further comprises.
The method of claim 6, wherein the QCI value,

Indicating at least one of Mission critical Push To Talk voice data, non Mission critical Push To Talk voice data, Mission critical Push To Talk signaling, and Mission critical data PCRF communication method.
In a group communication service enabler application server (GCSE-AS) of a mobile communication system,

A communication unit for communicating with another network entity; And

If the terminal receives information that the Multimedia Multicast Broadcast Service (MBMS) including the group communication service identifier is not supported and the bearer update of the terminal is required, the policy and charging rule function (PCRF: policy and charging) is received. a control unit controlling to transmit information necessary for bearer update to a rules function or a broadcast multicast service center (BM-SC);

GCSE-AS, including.
The method of claim 8, wherein the information required for bearer update is

GCSE-AS, characterized in that it comprises at least one of a group communication service identifier, a group communication service personality and a priority level.
The method of claim 8, wherein the control unit,

And a group communication service identifier and a priority level to be transmitted to the PCRF or the BM-SC using the group communication service identifier received from the terminal.
In the policy and charging rules function (PCRF) of a mobile communication system,

A communication unit for communicating with another network entity; And

A controller configured to receive information necessary for bearer update from a group communication service enabler application server (GCSE-AS) and to update bearer configuration using the received bearer update information;

PCRF comprising a.
The method of claim 11, wherein the information required for bearer update,

And at least one of a group communication service identifier, a group communication service personality, and a priority level.
The method of claim 11, wherein the control unit,

PCRF, characterized by controlling to determine at least one of a QoS Class Identifier (QCI), priority level, pre-emption capability, and pre-emption vulnerability.
The method of claim 13, wherein the QCI value,

Indicating at least one of Mission critical Push To Talk voice data, non Mission critical Push To Talk voice data, Mission critical Push To Talk signaling, and Mission critical data PCRF.