Communication method and communication device

Abstract

A communication method and a communication device are disclosed. The method includes the following. That is, for a terminal device that transitions to the non-connection mode, when a network device calls the terminal device to receive the first multicast service, the network device may further instruct the terminal device in the RRC non-connection mode whether to provide the first multicast service. The terminal device may perform at least one of the following based on the paging and instruction of the network device. That is, receiving the first multicast service in the RRC non-connection mode. Or, performing an RRC connection control procedure. According to this method, network congestion caused by the simultaneous access of a large number of terminal devices can be avoided, and the access of the terminal device can be effectively managed.

Description

Technical Field

[0001] Embodiments of the present application relate to the field of communications, and more specifically, to a communication method and a communication device.

Background Art

[0002] This application was filed with the State Intellectual Property Office of China on May 26, 2022, claims priority to Chinese Patent Application No. 202210580782.5 entitled "Communication Method and Communication Device", which is hereby incorporated by reference in its entirety.

[0003] Multicast and broadcast services (MBS) are classified into two types, namely broadcast services and multicast services. When network congestion occurs, for terminal devices receiving multicast services, the network device may release the terminal device from the radio resource control (RRC) connected mode to the RRC idle mode, whereby the terminal device receives the multicast service in the RRC idle mode. When the network congestion is alleviated, the network device may send a paging message to call a plurality of terminal devices receiving the multicast service in the RRC idle mode and cause them to transition to the connected mode. The plurality of called terminal devices may simultaneously execute an RRC connection establishment procedure or an RRC connection resume procedure. However, when a large number of terminal devices access the network simultaneously, network congestion occurs.

Summary of the Invention

[0004] Embodiments of the present application provide a communication method and a communication device to more effectively manage the access of terminal devices.

[0005] According to a first aspect, a communication method is provided. This method may be executed by a terminal device or by a component (such as a chip or circuit) of the terminal device. This is not limited in this specification. For ease of explanation, an example where this method is executed by a terminal device is used for the following description.

[0006] The method may include the following. That is, the terminal device receives a group paging message from a network device. Here, the group paging message includes first information, and the first information is used to call a terminal device group to receive a first multicast service, and the terminal device group includes terminal devices. And, the terminal device executes at least one of the following based on the first information and second information. Here, the second information is that the network device performs radio resource control ( RRC ) indicates whether to provide the first multicast service to a terminal device group in the non-connected mode. That is, the step of receiving the first multicast service in the RRC non-connected mode. Or, the step of executing an RRC connection control procedure.

[0007] In the above-described technical solution, the terminal device is notified whether the first multicast service should be provided in the RRC non-connected mode. As a result, some terminal devices can migrate to the RRC non-connected mode to receive the multicast service, and some terminal devices can migrate to the RRC connected mode to receive the multicast service. The access control procedure is extended, thereby avoiding network congestion caused by a large number of terminal devices accessing simultaneously after receiving the paging message, and effectively managing the access of the terminal devices.

[0008] In some implementations of the first aspect, for a terminal device to determine to receive a first multicast service in RRC idle mode based on first information and second information includes the following. That is, if the second information indicates that a network device provides a first multicast service to a group of terminal devices in RRC idle mode, the terminal device receives the first multicast service in RRC idle mode. Or, the terminal device starts an access control procedure based on the first information. If the terminal device is not permitted to access the network device, the terminal device receives the first multicast service in RRC idle mode, and the second information indicates that the network device provides a first multicast service to a group of terminal devices in RRC idle mode.

[0009] In some implementations of the first aspect, if the second information indicates that a network device provides a first multicast service to a terminal device in idle mode, the terminal device does not start an access control procedure.

[0010] In some implementations of the first aspect, for a terminal device to determine to receive a first multicast service in RRC idle mode based on first information and second information includes the following. That is, if the second information indicates that a network device does not provide a first multicast service to a group of terminal devices in RRC idle mode, the terminal device executes an RRC connection control procedure. Or, the terminal device starts an access control procedure based on the first information. If the terminal device is permitted to access the network device, the terminal device executes an RRC connection control procedure.

[0011] In some implementations of the first aspect, the second information is carried in a group paging message or is carried on a multicast control channel.

[0012] In some implementations in the first aspect, when the terminal device is not permitted to access the network device, the method further includes the following. That is, when the terminal device monitors the physical downlink control channel ( PDCCH ) corresponding to the multicast control channel within the running time of the first timer to obtain the configuration information of the first multicast service, the terminal device shall either terminate the access control procedure, or the terminal device shall stop starting the access control procedure after the first timer expires.

[0013] In some implementations in the first aspect, when the terminal device is not permitted to access the network device, the method further includes the following. That is, when the terminal device fails to obtain the configuration information of the first multicast service by monitoring the PDCCH of the multicast control channel within the running time of the first timer, the terminal device shall restart the access control procedure after the first timer expires. Here, the running time of the first timer is the duration that the terminal device needs to wait after it is not permitted to access the network device and before restarting the access control procedure again.

[0014] In some implementations in the first aspect, when the terminal device is not permitted to access the network device, the method further includes the following. That is, when the terminal device monitors the physical downlink control channel ( PDCCH ) corresponding to the multicast control channel within the running time of the first timer to obtain the configuration information of the first multicast service, the terminal device shall receive the first multicast service in the RRC idle mode, and without stopping the first timer, restart the access control procedure after the first timer expires. Here, the running time of the first timer is the duration that the terminal device needs to wait after it is not permitted to access the network device and before restarting the access control procedure again.

[0015] In some implementations in the first aspect, if the terminal device is not permitted to access the network device, the method further includes the following. That is, when the group paging message includes second information indicating that the network device provides a first multicast service to the terminal device in the non-connected mode, the terminal device either ends the access control procedure, or the terminal device skips starting the first timer, or the terminal device stops starting the access control procedure after the first timer expires. Here, the running time of the first timer is the duration that the terminal device needs to wait after the terminal device is not permitted to access the network device and before the terminal device restarts the access control procedure.

[0016] According to a second aspect, a communication method is provided. The method may be executed by a network device or may be executed by a component (such as a chip or a circuit) of the network device. This is not limited in this specification. For ease of explanation, an example where the method is executed by a network device is used to describe as follows.

[0017] The method may include the following. That is, the network device transmits a group paging message to the terminal device. Here, the group paging message includes first information, and the first information is used to call a terminal device group to receive a first multicast service, and the terminal device group includes the terminal device. Here, the network device transmits second information to the terminal device, and the second information indicates whether the network device provides a first multicast service to the terminal device group in the non-connected mode. ( RRC ) indicates whether to provide a first multicast service to the terminal device group in the non-connected mode.

[0018] In some implementations of the second aspect, the second information is carried in a group paging message, or the second information is carried on a multicast control channel.

[0019] For the effects corresponding to the second aspect, refer to the description of the effects in the first aspect. Details will not be described again in this specification.

[0020] According to a third aspect, a communication method is provided. This method may be executed by a terminal device, or may be executed by a component (such as a chip or a circuit) of the terminal device. This is not limited in this specification. For the sake of easy explanation, an example where this method is executed by a terminal device will be used to describe below.

[0021] This method may include the following. That is, when the terminal device is in the radio resource control ( RRC ) connected mode, steps of participating in a multicast service. When the terminal device is in the RRC connected mode, a step of receiving first information from a network device, where the first information indicates a multicast radio bearer ( MRB ) configuration, and the MRB configuration is the MRB configuration used by the terminal device to receive the multicast service in the RRC non-connected mode, steps. And a step of the terminal device determining the MRB configuration based on the first information.

[0022] In the above-described technical solution, when the terminal device is released from the non-connected mode, the MRB configuration used to receive the multicast service is specified. Therefore, before being released from the non-connected mode, the terminal device can determine early the MRB configuration used to receive the multicast service in the non-connected mode, thereby facilitating the continuous reception of the multicast service in the process of the terminal device being released from the non-connected mode.

[0023] In some implementations in the third aspect, the second information from the network device is received when the terminal device is in the RRC connected mode. Here, the second information indicates to the terminal device to receive the multicast service in the RRC idle mode. The terminal device migrates to the RRC idle mode. And when the terminal device is in the RRC idle mode, the multicast service is received by using the determined MRB configuration.

[0024] For example, the second information may be carried in an RRC release message, and the RRC release message indicates to the terminal device to migrate to the RRC idle mode. Further, the terminal device may still receive the multicast service based on the second information even after migrating to the idle mode. In this application, the second information may be understood as the reason for the terminal device to release the RRC connection is to receive the multicast service in the RRC idle mode.

[0025] In some implementations in the third aspect, the first information is used to operate the terminal device to obtain the MRB configuration, and the terminal device determining the MRB configuration based on the first information includes the following. That is, the terminal device monitors the physical downlink control channel ( PDCCH ) corresponding to the multicast control channel. And the terminal device determines the MRB configuration carried on the multicast control channel.

[0026] In some implementations in the third aspect, the first information indicates to the terminal device to receive the multicast service by using the MRB configuration used by the terminal device when the terminal device is in the RRC idle mode and receiving the multicast service in the RRC connected mode. The terminal device determining the MRB configuration based on the first information includes the following. That is, the terminal device determines, based on the first information, that the MRB configuration used by the terminal device is the MRB configuration for receiving the multicast service in the RRC connected mode.

[0027] According to a fourth aspect, a communication method is provided. This method may be executed by a network device or by a component (such as a chip or a circuit) of the network device. This is not limited in this specification. For the sake of easy explanation, an example in which this method is executed by a network device is used to explain as follows.

[0028] This method may include the following. That is, the network device determines that the terminal device participates in the multicast service. And the network device transmits the first information to the terminal device in the RRC ( RRC ) connected mode. Here, the first information indicates the multicast radio bearer ( MRB ) configuration, and the MRB configuration is the MRB configuration used by the terminal device to receive the multicast service in the RRC idle mode.

[0029] In some implementations in the fourth aspect, this method further includes the following. The network device transmits second information to the terminal device, and the fourth information indicates to the terminal device to transition to the RRC idle mode to receive the multicast service.

[0030] In some implementations of the fourth aspect, the first information is used to operate the terminal device to obtain the MRB configuration, and the method further includes the following. The network device transmits the MRB configuration to the terminal device. Here, the MRB configuration is carried in the multicast control channel information.

[0031] In some implementations of the fourth aspect, the network device transmitting the first information to a terminal device in the RRC connected mode includes the following. That is, the network device determines that the MRB configuration is the MRB configuration used by the terminal device to receive the multicast service in the RRC connected mode. And the network device transmits the first information to the terminal device in the connected mode. Here, the first information indicates to the terminal device that it can receive the multicast service by receiving the multicast service in the RRC connected mode using the MRB configuration used by the terminal device when the terminal device is in the RRC idle mode.

[0032] In some implementations of the fourth aspect, the method further includes the following. That is, the network device receives first indication information from the core network device. Here, the first indication information indicates the priority of one or more terminal devices. And the network device determines, based on the first indication information, the terminal devices that need to be released to the idle mode to receive the multicast service.

[0033] For the effects corresponding to the fourth aspect, refer to the description of the effects in the third aspect. Details will not be described again in this specification.

[0034] According to a fifth aspect, a communication device is provided. This device is configured to execute the method provided in the first aspect or the second aspect. Specifically, this device may include a unit and / or a module configured to execute the method in the first aspect or the second aspect, and any possible implementation in the first aspect or the second aspect, for example, a processing unit and / or a communication unit.

[0035] In one implementation, this device is a terminal device. When this device is a terminal device, the communication unit may be a transceiver or an input / output interface, and the processing unit may be at least one processor. Optionally, the transceiver may be a transceiver circuit. Optionally, the input / output interface may be an input / output circuit.

[0036] In another implementation, this device is a chip, a chip system, or a circuit used in a terminal device. When the device is a chip, a chip system, or a circuit used in a terminal device, the communication unit may be an input / output interface, an interface circuit, an output circuit, an input circuit, a pin, a related circuit, or the like on the chip, the chip system, or the circuit. And the processing unit may be at least one processor, a processing circuit, a logic circuit, or the like. When the device is a chip, a chip system, or a circuit used in a terminal device, it can be understood that the terminal device in the method in the first aspect or the second aspect, and any possible implementation in the first aspect or the second aspect is this device.

[0037] According to a sixth aspect, a communication device is provided. This device is configured to execute the method provided in the third aspect or the fourth aspect. Specifically, this device may include a unit and / or a module configured to execute the method in the third aspect or the fourth aspect, and any possible implementation in the third aspect or the fourth aspect, for example, a processing unit and / or a communication unit.

[0038] In one implementation, the present apparatus is a network device. When the present apparatus is a network device, the communication unit may be a transceiver or an input / output interface, and the processing unit may be at least one processor. Optionally, the transceiver may be a transceiver circuit. Optionally, the input / output interface may be an input / output circuit.

[0039] In another implementation, the present apparatus is a chip, chip system, or circuit used within a network device. When the present apparatus is a chip, chip system, or circuit used within a network device, the communication unit may be an input / output interface, interface circuit, output circuit, input circuit, pin, related circuit, or the like on the chip, chip system, or circuit. And the processing unit may be at least one processor, processing circuit, logic circuit, or the like. When the present apparatus is a chip, chip system, or circuit used within a network device, it can be understood that the terminal device in the method in the third aspect or the fourth aspect, and any possible implementation in the third aspect or the fourth aspect is the present apparatus.

[0040] According to a seventh aspect, a communication apparatus is provided. The present apparatus includes the following. That is, it includes at least one processor. Here, the at least one processor is coupled to at least one memory, the at least one memory is configured to store a computer program or instructions, and the at least one processor calls a computer program or instructions from the at least one memory and executes the computer program or instructions to enable the communication apparatus to execute the method in the first aspect or the second aspect, and any possible implementation in the first aspect or the second aspect.

[0041] In one implementation, the present apparatus is a terminal device.

[0042] In another implementation, the device is a chip, chip system, or circuit used within a terminal device. When the device is a chip, chip system, or circuit used within a terminal device, it can be understood that the method in the first aspect or the second aspect, and the terminal device in any possible implementation in the first aspect or the second aspect is the device.

[0043] According to an eighth aspect, a communication device is provided. The device includes at least one processor. Here, the at least one processor is coupled to at least one memory, the at least one memory is configured to store a computer program or instructions, and the at least one processor calls a computer program or instructions from the at least one memory and executes the computer program or instructions to enable the communication device to execute the method in the third aspect or the fourth aspect, and any possible implementation in the third aspect or the fourth aspect.

[0044] In one implementation, the device is a network device.

[0045] In another implementation, the device is a chip, chip system, or circuit used within a network device. When the device is a chip, chip system, or circuit used within a network device, it can be understood that the method in the third aspect or the fourth aspect, and the terminal device in any possible implementation in the third aspect or the fourth aspect is the device.

[0046] According to a ninth aspect, the present application provides a processor configured to execute the method provided in the above-described aspect.

[0047] Operations such as transmission and acquisition / reception related to the processor, unless otherwise specified or conflicting with the actual function or internal logic of the operations in the related descriptions of the operations, can be understood as operations such as the output and reception or input of the processor, or operations such as transmission and reception performed by the radio frequency circuit and the antenna. This is not limited in this application.

[0048] According to a tenth aspect, a computer-readable storage medium is provided. This computer-readable storage medium stores program code to be executed by a device, and the program code is used to execute the methods in the first aspect, the second aspect, the third aspect, or the fourth aspect, and any possible implementations in the first aspect, the second aspect, the third aspect, or the fourth aspect.

[0049] According to an eleventh aspect, a computer program product including instructions is provided. When this computer program product is executed on a computer, the computer can execute the methods in the first aspect, the second aspect, the third aspect, or the fourth aspect, and any possible implementations in the first aspect, the second aspect, the third aspect, or the fourth aspect.

[0050] According to a twelfth aspect, a chip is provided. This chip includes a processor and a communication interface. The processor reads instructions stored in the memory via the communication interface and executes the methods in the first aspect, the second aspect, the third aspect, or the fourth aspect, and any possible implementations in the first aspect, the second aspect, the third aspect, or the fourth aspect.

[0051] Optionally, in one implementation, the chip further includes memory. The memory stores a computer program or instructions. The processor is configured to execute the computer program or instructions stored in the memory. When the computer program or instructions are executed, the processor is configured to execute the method in the first, second, third, or fourth aspect, and any possible implementation in the first, second, third, or fourth aspect.

[0052] According to a thirteenth aspect, a communication system is provided. The communication system includes the communication devices shown in the seventh and eighth aspects.

Brief Description of the Drawings

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Embodiments for Carrying Out the Invention

[0054] With reference to the accompanying drawings, the technical solutions of the embodiments of the present application will be described below.

[0055] The technical solutions in the embodiments of the present application can be applied to various communication systems, such as long term evolution (LTE), 5th generation (5G), new radio (NR), internet of things (IoT), wireless-fidelity (Wi-Fi), wireless communication related to the 3rd generation partnership project (3GPP), or other wireless communications that may emerge in the future.

[0056] The technical solution provided in this application can be further applied to machine type communication (MTC), device-to-device (D2D) network, machine-to-machine (M2M) network, internet of things (IoT) network, or another network.

[0057] FIG. 1 is a diagram showing a communication system according to an embodiment of the present application. This communication system includes at least one network device, for example, the network device 110 shown in FIG. 1. The communication system 100 may further include at least one terminal device, for example, the terminal device 120 and / or the terminal device 130 shown in FIG. 1. The network device 110 can communicate with the terminal device 120 / 130 via a wireless link to exchange information. It can be understood that the network device and the terminal device may also be called communication devices.

[0058] The network device is a network-side device having a wireless transceiver function. The network device is within a radio access network (RAN) and can be a device that provides a wireless communication function to a terminal device, and is called a RAN device. For example, the network device can be a base station, an evolved NodeB (eNodeB), a next generation NodeB (gNB) in a 5G mobile communication system, a subsequent evolved 3GPP base station, a transmission reception point (TRP), an access node in a Wi-Fi system, a wireless relay node, or a wireless backhaul node. In communication systems using various radio access technologies (RATs), the name of the device having the base station function may be different. For example, the base station may be called an eNB or an eNodeB in an LTE system, and may be called a gNB in a 5G system or an NR system. The specific name of the base station is not limited in this application. The network device may include one or more transmission reception points at a co-located or non-co-located site. As another example, the network device may include one or more central units (CUs), one or more distributed units (DUs), or one or more CUs and one or more DUs. For example, the function of the CU can be implemented by one entity or various entities. For example, the function of the CU is further divided. In other words, the control plane and the user plane are separated and implemented by various entities, which are respectively a control plane CU entity (i.e., a CU-CP entity) and a user plane CU entity (i.e., a CU-UP entity). The CU-CP entity and the CU-UP entity can be coupled to the DU to jointly complete the function of the access network device.For example, the CU is responsible for processing non-real-time protocols and non-real-time services, and implementing the functions of the radio resource control (RRC) layer and the packet data convergence protocol (PDCP) layer. The DU is responsible for processing physical layer protocols and real-time services, and implementing the functions of the radio link control (RLC) layer, the media access control (MAC) layer, and the physical (PHY) layer. In this way, some functions of the radio access network device can be implemented by multiple network function entities. These network function entities may be network elements within a hardware device, or software functions executed on dedicated hardware, or virtual functions instantiated on a platform (such as a cloud platform, etc.). The network device may further include an active antenna unit (AAU). The AAU implements some physical layer processing functions and functions related to radio frequency processing and active antennas. Information in the RRC layer ultimately becomes information in the PHY layer or is converted from information in the PHY layer. Therefore, in this architecture, upper layer signaling such as RRC layer signaling can also be regarded as being targeted for transmission by the DU, or targeted for transmission by the DU and the AAU. It can be understood that the network device can be a device including one or more of the CU node, the DU node, and the AAU node. Furthermore, the CU may be classified as a network device within the radio access network (RAN), or the CU may be classified as a network device within the core network (CN). This is not limited in this application.As another example, in vehicle-to-everything (V2X) technology, the access network device can be a road side unit (RSU). Multiple access network devices in a communication system may be of the same type of base station, or may be of various types of base stations. The base station may communicate with the terminal device, or may communicate with the terminal device via a relay station. In the embodiments of the present application, the device configured to implement the function of the network device may be a network device, or a device capable of supporting the network device when implementing the function, for example, a chip system or a composite component, or a component capable of implementing the function of the access network device. This device can be installed within the network device. In the embodiments of the present application, the chip system may include a chip, or may include a chip and another individual component.

[0059] The terminal device is a user-side device having a wireless transceiver function, and can be a fixed device, a mobile device, a handheld device (such as a mobile phone, etc.), a wearable device, an in-vehicle device, or a wireless device built into the above-described device (such as a communication module, a modem, or a chip system, etc.). The terminal device is configured to connect people, things, mines, and the like, and can be widely used in various scenarios, such as device-to-device (D2D) communication between cellular communication devices, vehicle-to-everything (V2X) communication, machine-to-machine / machine-type communication (M2M / MTC), Internet of Things, virtual reality (VR), augmented reality (AR), industrial control, self-driving, remote medical, smart grid, smart furniture, smart office, smart wearable, smart transportation, smart city, unmanned aerial vehicle, and robots, etc. For example, the terminal device can be a handheld terminal in cellular communication, a communication device in D2D communication, an Internet of Things device in MTC, a surveillance camera in smart transportation and smart city, or a communication device in an unmanned aerial vehicle. The terminal device may also be called a user equipment (UE), a user terminal, a user device, a participant unit, a participant station, a terminal, an access terminal, an access station, a UE station, a remote station, a mobile device, a wireless communication device, or the like. In the embodiments of the present application, the device configured to implement the functions of the terminal device may be the terminal device itself, or a device that can support the terminal device when implementing the functions, such as a chip system or a composite component, or a component that can implement the functions of the terminal device. This device can be installed inside the terminal device. For the sake of simplicity of explanation, the terminal device is used as an example in this application for explanation.

[0060] To facilitate the understanding of the technical solutions in this application, related concepts in the embodiments of this application will be briefly described.

[0061] 1. RRC Mode

[0062] There are three modes in NR. That is, the RRC idle (RRC_IDLE) mode, the RRC inactive (RRC_INACTIVE) mode, and the RRC connected (RRC_CONNECTED) mode. The following briefly describes the three RRC modes.

[0063] (1) RRC_CONNECTED (RRC connected mode): The RAN has the context of the UE, and the UE has a signaling connection with the RAN. The UE can receive system messages and messages delivered by the RAN, which are used to control the UE to perform data transmission and handover and notify the UE of related scheduling information, and the RAN can receive the channel quality information fed back by the UE.

[0064] (2) RRC_INACTIVE (RRC inactive mode): The connection between the RAN and the core network is maintained, and resources are not allocated to the air interface, whereby the service can be quickly restored and the experience of delay-sensitive applications is improved. Furthermore, the power-saving effect of the user terminal in the inactive mode is almost the same as that in the idle mode. This extends the battery life of the mobile phone.

[0065] (3) RRC_IDLE (RRC Idle Mode): The RAN does not have the UE's context, and the UE does not have a signaling connection with the RAN. In this mode, the UE can receive system messages and paging messages for cell selection and reselection. If the UE needs to establish a connection with the network for specific purposes (such as service requests, location updates, and paging), the establishment of an RRC connection is triggered. After the RRC connection is established, the UE transitions to the RRC connected mode.

[0066] It should be understood that the RRC disconnected mode in this application can be the RRC idle mode and / or the RRC inactive mode. The disconnected mode in this application can be replaced with the RRC idle mode and / or the RRC inactive mode.

[0067] Furthermore, the UE connection management (CM) mode includes an idle mode (CM-IDLE), a connected mode with an inactive mode (CM-CONNECTED with RRC_INACTIVE), and a connected mode (CM-CONNECTED). It should be understood that in the CM-IDLE mode, the UE does not establish a signaling connection with the core network. For example, in the RRC_IDLE mode, the UE moves between various cells through cell reselection. In the CM-CONNECTED mode, the UE establishes a signaling connection with the core network, such as the RRC_CONNECTED mode and the RRC_INACTIVE mode.

[0068] 2. Multicast and Broadcast Service (MBS)

[0069] MBS is a service targeted at multiple UEs, such as a live broadcast service, a program playback service incorporating a schedule, and a batch software update service. From the perspective of the management and control procedures between terminals and the transmission method, MBS designed for NR is classified into two types. That is, a broadcast service and a multicast service. As shown in Figure 2, MBS is transmitted from a data server. First, the data server transmits MBS data to core network equipment, then the core network equipment transmits the MBS data to the base station, and finally, the base station transmits the MBS data to at least one UE that receives the MBS. When the core network equipment transmits the MBS data to the base station, the MBS data is transmitted through the public transmission channel MBS session, and each MBS session may include at least one MBS quality of service (QoS) flow. When the base station transmits the MBS data to the UE, the MBS data is transmitted through the MBS radio bearer. For one MBS radio bearer, there are two transmission methods. That is, first, the point to multi-point (PTM) transmission method, and second, the point to point (PTP) transmission method.

[0070] 3. Multicast service

[0071] The multicast service is designed for services with high QoS requirements. The multicast service can provide the same QoS level as that of the unicast service. In the existing protocol, the multicast service is radio resource control ( RRC )It can be provided only to UEs in the connected mode, and the access network device and the core network device need to hold UE information corresponding to the multicast service group. Specifically, for the multicast service, the core network needs to manage the participation and withdrawal of UEs. The control signaling between the core network and the base station depends on the protocol data unit (PDU) session, and a new MBS QoS flow is introduced. The base station supports the transmission of data to UEs in two modes, namely PTP and PTM, and supports dynamic switching between PTP and PTM, which is controlled by the base station. As shown in Figure 3, the base station can transmit the same multicast service to multiple UEs, that is, execute PTM transmission, by using the group radio network temporary identifier (G-RNTI). Furthermore, the base station can further allocate a cell radio network temporary identifier (C-RNTI) corresponding to each UE. Here, the C-RNTI is used to execute PTP transmission as needed. The multicast service further supports the invalidation or activation of the MBS session caused by the core network. The UE does not recognize the service mode.

[0072] 4. Broadcast Service

[0073] The broadcast service is designed for services with low QoS requirements. The broadcast service supports UEs in any RRC mode. The core network and base stations do not need to maintain a group of UEs that receive the relevant broadcast service. When the broadcast service is being provided, the UE autonomously receives the broadcast service based on the configuration information. Similar to the multicast service, the broadcast service is designed only for the downlink (DL). Different from the multicast service, the broadcast service supports only the PTM transmission mode. For the UE, the configuration for receiving the broadcast service is completely independent of the configuration for receiving the multicast service.

[0074] 5. Multicast Control Channel and Multicast Traffic Channel

[0075] Two logical channels, namely the Multicast Control Channel ( multicast control channel, MCCH) and the Multicast Traffic Channel ( multicastThe traffic channel (MTCH) is introduced into the broadcast technology of NR MBS. The MCCH is used to transmit control information. The MCCH periodically transmits control information, and the MBS broadcast configuration information is carried on the MCCH. The MBS broadcast configuration information is the configuration information of the MTCH. For example, the configuration information of the MTCH includes configurations required to receive broadcast services, such as the G-RNTI corresponding to the MTCH and the temporary multicast group identifier (TMGI). The MTCH carries the user data of the broadcast service. The MTCH is scheduled through the MCCH. The MTCH is configured per G-RNTI, that is, per MBS. The base station can simultaneously schedule service data to multiple UEs through the G-RNTI, and each G-RNTI can be associated with at least one broadcast service.

[0076] It should be understood that in various communication systems, the channels described above may correspond to various names. For example, in the 4th generation (4G) communication system, the multicast control channel may be the single cell multicast traffic control channel (SC-MCCH). As another example, in the 5G communication system, the multicast control channel may be the MC-MCCH. In the future technology development process, channels having similar functions to those of the multicast traffic control channel may have different names, or in various communication environments, communication scenarios, or communication technologies, channels having the same function may have different names. However, different names of channels having similar or the same functions in various systems do not constitute limitations on the channel content and functions. The multicast control channel in this application can be used to transmit control information, and the multicast traffic channel can be used to transmit user data.

[0077] 6. Multicast Control Channel Change Notification (MCCH change notification)

[0078] As shown in Figure 4, the MCCH is repeatedly transmitted in each modification period (MP), and the repetition period (RP) is included in the figure. In one MP, the content of the MCCH is the same. When the MCCH within different MPs changes, the network device transmits a physical downlink control channel (PDCCH). Here, the PDCCH includes an MCCH change notification. When the UE detects a field corresponding to the MCCH change notification, for example, 2 bits, on the PDCCH, it is regarded that the content of the MCCH has changed, and the UE re-acquires the MCCH. The first bit in the MCCH change notification indicates that the reason for changing the MCCH is session start, and the second bit in the MCCH change notification indicates that the reason for changing the MCCH is session change, session stop, or update of the neighbor cell list. When acquiring the MCCH, the UE needs to detect the PDCCH scrambled by using the MCCH-RNTI to obtain the scheduling information of the MCCH.

[0079] 7. Multicast Session Identifier (MBS session ID)

[0080] The MBS session ID identifies multicast and broadcast services. For example, one multicast session identifier can be associated with one multicast and broadcast service. For example, the multicast session identifier can be the TMGI.

[0081] 8. Procedures for Invalidation, Activation, and Release of MBS Sessions

[0082] The procedure for invalidating an MBS session is applicable to multicast. The MBS session invalidation procedure is triggered by a multicast session management function (MB-SMF) network element. When there is no downlink data to be transmitted within a certain time period, the MB-SMF receives a notification from a user plane function (MB-UPF) network element, or when the MB-SMF directly receives a request forwarded by an application function (AF) network element or a network exposure function (NEF), the MBS session invalidation procedure is used to invalidate the MBS data resources of a 5G access network (NG-RAN) node. As shown in Figure 5, when triggered by a 5G core network (5GC), for example, the access and mobility management function (AMF) network element in Figure 5 sends a multicast session invalidation request to the RAN, and the RAN releases the radio resources of the multicast session and stops transmitting multicast session data to the UE. The multicast session mode changes from the active mode to the inactive mode. The base station may or may not release the RRC connection of the UE, but the base station does not explicitly notify the UE of the invalidation of the MBS session.

[0083] The activation process of the MBS session is applicable only to multicast. The activation process of the MBS session is triggered by the MB-SMF. When the MB-SMF receives a notification regarding MBS downlink data from the MB-UPF, or when the MB-SMF directly receives a request forwarded by the AF or NEF, the activation procedure of the MBS session is triggered. The activation procedure of the MBS session activates the MBS data resources of the NG-RAN node, such as radio resources for establishing a multicast session, and is used to transmit multicast session data to the UE. Further, UEs participating in the multicast session and in the CM-IDLE mode and CM-CONNECTED+RRC inactive mode, i.e., UEs in the RRC disconnected mode, are paged. The activation procedure for these UEs can be triggered by an AF request or a notification regarding the data of the MB-UPF, and the multicast session mode changes from the inactive mode to the active mode. In Figure 6, the message used by the AMF to page a UE in the CM-IDLE mode may be a group paging message (when the base station supports multicast), or a unicast paging message (when the multicast service is provided in the unicast manner without the base station supporting multicast). When the AMF sends a multicast session activation request message to the RAN, the paging procedure of the RAN can be triggered.

[0084] The MBS release procedure is actuated by the core network. If the CN decides to release one multicast service or remove one UE from the multicast service, the procedure shown in FIG. 7 may be executed. As shown in FIG. 7, if the CN determines that there is a UE in the CM-IDLE mode, the CN starts paging to enable the UE to transition to the connected mode. After the UE has transitioned to the connected mode, the CN may initiate a PDU session modification request to the RAN. The detailed message sent for paging may be a group paging message (if the base station supports multicast) or a unicast paging message (if the multicast service is provided in unicast fashion without the base station supporting multicast).

[0085] Unless otherwise specified in this application, the mode of MBS may also be understood as the mode of the MBS session, and it should be understood that releasing MBS may also be understood as releasing the MBS session. In other words, unless otherwise specified in this application, "service" and "session" may be replaced with each other.

[0086] 9. Multicast Radio Bearer( multicast radio bearer, MRB)

[0087] Network devices and terminal devices have a specific protocol stack structure and communicate with each other. As shown in FIG. 8, the user plane protocol stack structure may include an RRC layer, a service data adaptation protocol (SDAP) layer, a PDCP layer, an RLC layer, a MAC layer, a physical (PHY) layer, and the like. The physical layer is located at the lowest layer (layer 1), the MAC layer, RLC layer, PDCP layer, and SDAP layer belong to the second layer (layer 2), and the RRC layer belongs to the third layer (layer 3). For the user plane protocol stack of MBS transmission, data is transmitted in the direction indicated by the arrow in FIG. 8 (for the MBS service, the transmission direction is from the base station to the UE). The data first arrives at the SDAP layer of the base station, is mapped by the SDAP layer, and then transmitted to the corresponding PDCP entity. After being processed by the PDCP layer of the base station, the data is transmitted to the RLC layer and the MAC layer. After the corresponding processing, the data is transmitted from the physical layer and transmitted to the UE side through the air interface. Then, each protocol layer on the UE side sequentially performs corresponding processing on the data packet in the reverse processing order of that of the base station. At the base station and the UE side, the processing performed on the data packet by each layer is sometimes collectively called a radio bearer (RB) in general. Each part of the data within the radio bearer needs to be processed by each layer, and each layer has a corresponding functional entity to execute the corresponding function. Each radio bearer configuration includes one PDCP entity, each radio bearer configuration is associated with at least one RLC entity, and each RLC entity corresponds to one logical channel.

[0088] It should be understood that the protocol stack structure described in FIG. 8 is merely an example and does not constitute a limitation. The number of layers may be less or more, and the functions of some layers may be integrated into one of the layers, or a structural change may be made. This is not limited in this application.

[0089] For MBS, user plane data is carried by MRBs. In particular, MRBs include the following three types, namely, PTP-only MRBs, PTM-only MRBs, and split MRBs. Here, split MRBs include PTP MRBs and PTM MRBs. As shown in Figure 9, a PTP-only MRB is associated with one PTP RLC entity, a PTM-only MRB is associated with one PTM RLC entity, and a split MRB is associated with one PTM RLC entity and one PTP RLC entity. PTM RLC is the same for multiple UEs, and the multiple UEs monitor PDCCH by using the same G-RNTI. PTP RLC is independent for each UE, and each UE monitors PDCCH by using its respective C-RNTI.

[0090] It should be understood that one MBS session corresponds to one or more MRBs, that is, one service may correspond to one or more MRBs.

[0091] Furthermore, it should be understood that one MRB corresponds to only one G-RNTI, but one G-RNTI may correspond to multiple MRBs, and the multiple MRBs corresponding to one G-RNTI may or may not be MRBs of the same service.

[0092] 10. Access Control

[0093] Access control is a solution for controlling network congestion on the network side. In a possible scenario, when the load on the network side is heavy, before starting the RRC connection control, the terminal device needs to perform access control to determine whether the terminal device is permitted to perform access. In this way, some terminal devices can be prohibited from starting the RRC connection control, and the network load can be limited. Optionally, the terminal device can be prohibited from starting the RRC connection control access within a timer. The RRC connection control includes an RRC connection establishment procedure (specific procedures are shown in FIG. 10) or an RRC connection resume procedure (specific procedures are shown in FIG. 11).

[0094] Unified access control (UAC) is a common access control method in 5G systems and LTE systems, and the random mechanism of UAC can separate the access opportunities of UEs. In a 5G system, a UE can determine whether its access is prohibited according to the UAC parameters. Hereinafter, the steps of UAC will be briefly described.

[0095] Step 1: The UE receives the UAC parameters broadcast by the network device through the system information block (SIB) 1.

[0096] Step 2: When the UE starts a service, the non-access stratum (NAS) of the UE determines an access category (AC) based on the service type of the service for the RRC layer of the UE to perform an access decision.

[0097] Step 3: The UE determines whether its access is prohibited based on the AC.

[0098] When the value of AC is 0, it indicates that the UE is permitted to perform access and the RRC connection control procedure is executed. When the value of AC is not equal to 0, it indicates that the access of the UE is prohibited and Step 4 is executed.

[0099] Step 4: Based on AC, the UE determines a set of barring parameters (denoted as parameter #1 in this specification) corresponding to AC in the UAC parameter. Here, parameter #1 includes barring for access identity, barring factor, and barring time. The barring factor can be understood as the ratio at which the terminal device is permitted to perform access.

[0100] Step 5: Based on the configuration of the UE, the UE determines one access identity (AI). Regarding the barring for access identity in parameter #1, if the bit corresponding to the AI determined by the UE is 0, it indicates that the UE is permitted to perform access. Regarding the barring for access identity in parameter #1, if the bit corresponding to the AI determined by the UE is not 0, it indicates that the access of the UE is prohibited, and based on the barring factor and barring time within parameter #1, the access control decision continues to be executed.

[0101] The two parameters are used as follows. That is, the UE randomly selects a value between [0,1]. If the random value is smaller than the prohibition coefficient (for example, the prohibition coefficient is 50%), it means that the UE is permitted to execute access. If the random value is greater than or equal to the prohibition coefficient (for example, the prohibition coefficient is 50%), the access of the UE is prohibited. When the access of the UE is prohibited, the UE continues to determine the duration #1 based on the prohibition time (for example, the prohibition time is 128 seconds) and starts a timer. The execution time of the timer is the duration #1. The terminal device can restart the determination of the UAC access only after the timer expires. For example, the timer may be T390 or T302. T390 is a timer that is started when an access attempt is prohibited during the access prohibition check for the access category. T302 is a timer that is started when the UE receives an RRC connection rejection or after receiving an RRC connection rejection during a specific duration.

[0102] It should be understood that the above-described procedure only briefly explains some implementation steps in the UAC procedure. The specific UAC procedure does not constitute a limitation to this application, and it may be another AC not mentioned or a special design.

[0103] When network congestion occurs, for a UE receiving a multicast service, the network device may release the UE from the RRC connection mode (abbreviated as the "connected mode" in this application) to the RRC disconnected mode (abbreviated as the "disconnected mode" in this application), so that the UE receives the multicast service in the disconnected mode. However, currently, for a UE released from the connected mode to the disconnected mode, the processing of the MRB when the UE receives the multicast service in the disconnected mode is not specified, and currently, it is also unclear which UE can be released to the disconnected mode to receive the multicast service.

[0104] From such a perspective, the present application provides a method for effectively solving the above-described technical problems. Hereinafter, the method provided in the present application will be described in detail.

[0105] FIG. 12 is a schematic flowchart showing a communication method according to the present application. This method may include the following steps.

[0106] S1201: The terminal device participates in the multicast service in the connected mode. Accordingly, the network device determines that the terminal device is participating in the multicast service.

[0107] It should be understood that when the terminal device participates in the multicast service, when the network device transmits the multicast service, the terminal device can receive the data of the multicast service.

[0108] Furthermore, even when the terminal device participates in the multicast service in the connected mode, if the network device does not transmit any data of the multicast service, it should be understood that the terminal device will not receive the data of the multicast service.

[0109] Therefore, optionally, the network device may transmit the multicast service to the terminal device in the connected mode. Accordingly, the terminal device in the connected mode receives the multicast service from the network device.

[0110] S1202: The network device transmits first information to the terminal device in the connected mode. Here, the first information indicates an MRB configuration, and the MRB configuration is the MRB configuration used by the terminal device to receive the multicast service in the non-connected mode. Accordingly, the terminal device in the connected mode receives the first information from the network device.

[0111] Optionally, when a network device determines that a terminal device participates in multiple multicast services, the first information may indicate part or all of the MRB configurations of part or all of the multiple multicast services. For example, in S1201, when a network device determines that a terminal device participates in multicast service #1, multicast service #2, and multicast service #3, the first instruction in S1202 may instruct the terminal device to receive part or all of the MRB configuration of the multicast services within multicast service set #1 in the disconnected mode. Multicast service set #1 includes at least one of multicast service #1, multicast service #2, and multicast service #3.

[0112] For ease of explanation, an example in which the first information indicates part or all of the required MRB configuration when a terminal device receives services within multicast service set #1 in the disconnected mode in S1202 will be used to explain below.

[0113] It should be understood that the terminal device that receives the first information may then need to be released from the disconnected mode to receive the multicast service and is the terminal device determined by the network device. Therefore, optionally, before S1202, the method further includes the following. That is, the network device determines at least one terminal device that needs to be released from the disconnected mode to receive the multicast service. For example, the network device may determine the terminal device that needs to release the RRC connection in the following manner.

[0114] Method 1: The network device determines the terminal device that needs to release the RRC connection based on the type of multicast service received by the terminal device. For example, the network device determines that a terminal device that only receives multicast services is a terminal device that needs to release the RRC connection, or the network device determines that a terminal device that only receives multicast services and for which the network device provides multicast services when the terminal device is in the disconnected mode is a terminal device that needs to release the RRC connection.

[0115] Method 2: The network device determines the terminal device that needs to release the RRC connection based on the priority information of the terminal device from the core network. As can be seen from the above description, the core network needs to manage the terminal devices participating in the multicast service. Therefore, the core network can indicate the priority information of the terminal device to the network device.

[0116] In a possible implementation, the priority information of the terminal device can be indicated by using a value. Optionally, the larger the value, the higher the priority of the terminal device (i.e., the more important the terminal device), or the smaller the value, the higher the priority of the terminal device. Optionally, the priority of the terminal device can be one of positive integers such as 1, 2, and 3. Optionally, the priority information can indicate the importance of the terminal device. For example, if the priority is 1, it means that the terminal device is an important terminal device. Or, if the priority is 2 or less, it means that the terminal device is an important terminal device. Or, if the priority is 2 or more, it means that the terminal device is an important terminal device. In this implementation, the network device can determine, based on the priority information of the terminal device, that important terminal devices remain in the connected mode and that some unimportant terminal devices are terminal devices that need to release the RRC connection.

[0117] In another possible implementation, the priority information of the terminal device can be indicated through a field or information element with enumerated values {important, unimportant}, enumerated values {priority, non - priority}, or enumerated values {yes, no}. For example, the priority of the terminal device is indicated through the enumerated value {important} which represents that the terminal device is an important terminal device, and the network device maintains the terminal device in the connection mode. Or, the priority of the terminal device is indicated through the enumerated value {unimportant} which represents that the terminal device is not an important terminal device. The network device determines that the terminal device can be disconnected.

[0118] In yet another possible implementation, the priority information of the terminal device can be indicated through the enumerated values {important}, {priority}, or {yes}. When the enumerated value exists, it represents that the corresponding terminal device is an important terminal device. When the enumerated value does not exist, it represents that the corresponding terminal device is not an important terminal device.

[0119] As can be seen in this way, in the above - described implementation, the terminal device that needs to release the RRC connection is determined based on various requirements. For example, a terminal device with a low priority executes RRC release, and a terminal device with a high priority maintains the RRC connection mode to more accurately select the terminal device that needs to be disconnected to receive the multicast service.

[0120] S1203: The terminal device determines the MRB configuration based on the first information. The MRB configuration is part or all of the MRB configuration required by the terminal device to receive services within the multicast service set #1 in the non - connected mode.

[0121] For example, based on various indication methods in the first information, there may be several ways as to how the first information indicates the MRB configuration and how the terminal device determines the MRB configuration.

[0122] Method 1:

[0123] The first information is used to operate the terminal device so as to obtain the MRB configuration. Accordingly, the terminal device in the connected mode monitors the PDCCH corresponding to the multicast control channel based on the first information, and in the connected mode, obtains the MRB configuration included in the multicast control channel. Alternatively, the terminal device in the connected mode starts monitoring the PDCCH corresponding to the multicast control channel based on the first information and obtains a part of the MRB configuration. In the process of obtaining the MRB configuration, the terminal device may transition to the non-connected mode, and after transitioning to the non-connected mode, the terminal device continues to obtain the remaining part of the MRB configuration.

[0124] It can be understood that the MRB configuration in Method 1 is all of the MRB configuration required by the terminal device to receive services within the multicast service set #1 in the non-connected mode.

[0125] For example, the multicast control channel may be a multicast control channel for multicast or a multicast control channel for multiplexed broadcast. This is not particularly limited in this application. In the present embodiment of this application, MCCH represents the multicast control channel, but it should be understood that MCCH does not need to constitute any limitation on the content and function of the channel. This application does not exclude the possibility of naming the multicast control channel by using another name. For example, the multicast control channel for multicast may continue to use the name MCCH of the multicast control channel for broadcast, or may use another name.

[0126] For example, the first information may be a MAC control element (CE), or may also be downlink control information (DCI). For example, when the first information is a MAC CE, the MAC CE may be scrambled by using the C-RNTI of the terminal device or by using the G-RNTI of the service within the multicast service set #1 monitored by the terminal device in the connected mode.

[0127] In one implementation, after determining the MRB configuration, the terminal device may establish a new MRB used by the terminal device to receive services within the multicast service set #1 in the connected mode and in the non-connected mode based on the MRB configuration. After transitioning to the non-connected mode, the terminal device releases or suspends the MRB previously used by the terminal device to receive services within the multicast service set #1 in the connected mode and reserves the newly established MRB used by the terminal device to receive services within the multicast service set #1 in the non-connected mode.

[0128] In another implementation, after determining the MRB configuration and after transitioning to the non-connected mode, the terminal device establishes a new MRB used by the terminal device to receive services within the multicast service set #1 in the non-connected mode based on the MRB configuration, and releases or suspends the MRB previously used by the terminal device to receive services within the multicast service set #1 in the connected mode.

[0129] In order to receive services within multicast service set #1 in the non-connection mode, the MRB (abbreviated as "non-connection mode MRB" in method 1) used by the terminal device is established based on the MRB configuration (referred to as "MRB configuration in the non-connection mode" in method 1) used by the terminal device to receive services within multicast service set #1 in the non-connection mode. It should be understood that in order to receive services within multicast service set #1 in the connection mode, the MRB (abbreviated as "connection mode MRB" in method 1) used by the terminal device is established based on the MRB configuration (referred to as "MRB configuration in the connection mode" in method 1) used by the terminal device to receive services within multicast service set #1 in the connection mode.

[0130] As can be seen in this way, in the above-described method, the network device operates the terminal device to pre-acquire the MRB configuration in the non-connection mode through the first information in the connection mode. In this way, the terminal device in the RRC connection mode can pre-establish the MRB in the non-connection mode based on the MRB configuration in the non-connection mode. Thus, when the terminal device is released from the connection mode to the non-connection mode, the terminal device can receive multicast services by using the established MRB in the non-connection mode, ensuring the continuity of receiving multicast services by the terminal device. After transitioning to the non-connection mode, compared with the case where the terminal device starts to acquire the MRB configuration in the non-connection mode, in this embodiment, after transitioning to the non-connection mode, the terminal device may establish the MRB in the non-connection mode by using the pre-acquired MRB configuration in the non-connection mode, or it can be understood that before transitioning to the non-connection mode, a part of the MRB configuration can be pre-acquired. In this way, the time period of interruption of receiving multicast services by the terminal device can be shortened, and the continuity of multicast services can be improved.

[0131] Method 2:

[0132] The first information indicates whether the terminal device in the non - connected mode receives the services within the multicast service set #1 by using the MRB configuration used by the terminal device to receive the services within the multicast service set #1 in the connected mode.

[0133] Optionally, the first information indicates each MRB corresponding to each service within the multicast service set #1. That is, the indication granularity of the first information is each MRB. For example, the first information indicates that MRB #11 of service #1 within the multicast service set #1 can continue to be used, and MRB #12 of service #1 within the multicast service set #1 indicates that it cannot continue to be used. Further, the first information indicates that MRB #21 of service #2 within the multicast service set #1 cannot continue to be used, and MRB #22 of service #2 within the multicast service set #1 indicates that it cannot continue to be used. Details will not be described again in this specification.

[0134] Optionally, the first information indicates all the MRBs of each service within the multicast service set #1. That is, the indication granularity of the first information is each service. For example, the first information indicates that all the MRBs of service #1 within the multicast service set #1 can continue to be used. As another example, it indicates that all the MRBs of service #2 within the multicast service set #1 cannot continue to be used. Details will not be described again in this specification.

[0135] Optionally, the first information indicates all MRBs of all services within multicast service set #1. That is, the indication granularity of the first information is each UE. For example, the first information indicates that all MRBs of all services within multicast service set #1 can continue to be used. As another example, the first information indicates that all MRBs of all services within multicast service set #1 can no longer continue to be used.

[0136] [1] When the first information indicates that the MRB configuration used by the terminal device to receive services within multicast service set #1 in the connected mode can continue to be used, the terminal device continues to use all or part of the MRB configuration used by the terminal device to receive service #1 in the connected mode.

[0137] Regardless of whether the indication granularity of the first information is any of each MRB, each service, or each UE, it should be understood that further processing needs to be performed for each type of MRB. For ease of understanding, an example where multicast service set #1 includes service #1 and the MRB corresponding to service #1 includes MRB #1 is used to explain in more detail below. For example, in case [1], the terminal device may perform at least one of the following operations.

[0138] (1) When the MRB #1 used by the terminal device to receive service #1 in the connected mode is a PTP dedicated MRB, the PTP dedicated MRB is suspended. In this case, the terminal device can monitor the PDCCH corresponding to the MCCH in the connected mode or the non-connected mode to obtain (determine) the MRB configuration used by the terminal device to receive service #1 in the non-connected mode. The terminal device establishes a new MRB based on the MRB configuration and receives service #1 in the non-connected mode.

[0139] When the terminal device is in the non-connected mode, it should be understood that the MRB configuration used to receive Service #1 is carried on the MCCH.

[0140] Furthermore, when the indication granularity of the first information is each MRB, and when MRB #1 used to receive Service #1 in the connected mode is a PTP dedicated MRB, it should also be understood that the first information indicates that MRB #1 cannot be continuously used.

[0141] (2) When MRB #1 used to receive Service #1 when the terminal device is in the connected mode is a PTM dedicated MRB, the PTM dedicated MRB is not paused, and the terminal device continuously receives Service #1 in the non-connected mode by using the PTM dedicated MRB.

[0142] (3) When MRB #1 used to receive Service #1 when the terminal device is in the connected mode is a split MRB, the terminal device continuously receives Service #1 in the non-connected mode by using the PTM MRB within the split MRB. Optionally, the PTP MRB within the split MRB is paused.

[0143] [2] When the first information indicates that the MRB configuration used by the terminal device to receive services within the multicast service set #1 in the connected mode is not used, the terminal device pauses all MRBs used by the terminal device to receive services within the multicast service set #1 in the connected mode. The terminal device obtains, through monitoring, the MRB configuration used to receive services within the multicast service set #1, and establishes new MRBs based on the MRB configuration obtained to receive services within the multicast service set #1 in the non-connected mode.

[0144] [3] If the first piece of information does not exist, that is, if it does not indicate whether the network device can continue to use the MRB configuration in the connection mode, the terminal device determines whether it can use the MRB in the connection mode. If the terminal device can use the MRB in the connection mode, it receives the services within the multicast service set #1 in the non-connection mode. If the terminal device cannot use the MRB in the connection mode (for example, the MRB in the connection mode is a PTP dedicated MRB), the terminal device suspends the unusable MRB and, in the non-connection mode, establishes a new MRB to receive the services within the multicast service set #1.

[0145] For ease of understanding, an example where the multicast service set #1 includes service #1 and the MRB of service #1 includes MRB #1 is used to explain in more detail below. For example, in case [3], the terminal device may perform the following operations.

[0146] (1) If the MRB used by the terminal device to receive service #1 in the connection mode is a PTP dedicated MRB, the PTP dedicated MRB is suspended. In this case, the terminal device monitors the PDCCH corresponding to the MCCH in the connection mode to obtain the MRB configuration included in the MCCH, which is the MRB configuration used by the terminal device to receive service #1 in the non-connection mode. The terminal device establishes a new MRB based on the MRB configuration to receive service #1 in the non-connection mode.

[0147] (2) When the MRB used by the terminal device is a PTM dedicated MRB in order to receive Service #1 in the connected mode, the terminal device may obtain the MRB configuration used by the terminal device to receive Service #1 in the non-connected mode through monitoring in the connected mode or the non-connected mode. The terminal device checks whether it is necessary to update the MRB used by the terminal device to receive Service #1 in the connected mode. If it is necessary to update the MRB used by the terminal device to receive Service #1 in the connected mode, the terminal device establishes a new MRB based on the MRB configuration obtained through monitoring and receives Service #1 in the non-connected mode. If it is not necessary to update the MRB used by the terminal device to receive Service #1 in the connected mode, the terminal device continues to receive Service #1 in the non-connected mode by using the PTM dedicated MRB.

[0148] (3) When the MRB used by the terminal device is a split MRB in order to receive Service #1 in the connected mode, similarly, the terminal device can obtain the MRB configuration used to receive Service #1 in the connected mode through monitoring and check whether it is necessary to update the PTM MRB in the split MRB. If it is necessary to update the PTM MRB in the split MRB, the terminal device establishes a new PTM MRB based on the MRB configuration obtained through monitoring. This new PTM MRB is used to receive Service #1 in the non-connected mode. If it is not necessary to update the PTM MRB in the split MRB, the terminal device continues to receive Service #1 in the non-connected mode by using the PTM MRB in the split MRB and, optionally, suspends the PTP MRB in the split MRB.

[0149] As can be understood in this way, in the above-described method, the terminal device can determine in advance, through the first information, whether the MRB configuration in the non-connection mode is the same as the MRB configuration in the connection mode in the connection mode. If the MRB configuration in the non-connection mode is the same as the MRB configuration in the connection mode, the terminal device does not need to establish a new MRB, which can reduce the energy consumption of the terminal device and the network device, and the terminal device can start receiving services in the non-connection mode earlier. If the MRB configuration in the non-connection mode is different from the MRB configuration in the connection mode, the terminal device can obtain the MRB configuration in the non-connection mode in advance. In this way, when the terminal device establishes a new MRB in the non-connection mode based on the MRB configuration in the non-connection mode in the connection mode, the continuity of receiving the multicast service can be ensured when the terminal device is released from the connection mode to the non-connection mode. After migrating to the non-connection mode, compared with the case where the terminal device starts to obtain the MRB configuration in the non-connection mode, in this embodiment, after migrating to the non-connection mode, it can be understood that the terminal device establishes a new MRB in the non-connection mode based on the MRB configuration in the non-connection mode. In this way, the time period of interruption of receiving the multicast service by the terminal device can be shortened, and the continuity of the multicast service can be improved.

[0150] Method 3:

[0151] Method 3 can be a combination of Method 1 and Method 2. The terminal device receives the first information in Method 1 and the first information in Method 2, and based on the first information in Method 1 and the first information in Method 2, the terminal device determines whether all or part of the MRB configuration used by the terminal device should continue to be used or re-acquired in order to receive Service #1 in the connection mode. For example, the terminal device determines whether the MRB configuration in the non-connection mode is the same as the MRB configuration in the connection mode based on the first information in Method 2. If the MRB configuration in the non-connection mode is the same as the MRB configuration in the connection mode, after being released from the non-connection mode, the terminal device continues to receive the services within the multicast service set #1 by using the MRB in the connection mode. If the MRB configuration in the non-connection mode is different from (completely different or partially different from) the MRB configuration in the connection mode, the terminal device may establish a new non-connection mode MRB in the connection mode based on the MRB configuration in the non-connection mode indicated by the first information in Method 1. Further, after transitioning to the non-connection mode, the terminal device receives the services within the multicast service set #1 based on the newly established non-connection mode MRB. Alternatively, the terminal device may establish a new MRB in the connection mode. The MRB corresponds to the difference between the MRB configuration in the non-connection mode and the MRB configuration in the connection mode. In the MRB configuration in the non-connection mode and the MRB configuration in the non-connection mode, the MRB corresponding to the same MRB configuration is reserved and remains unchanged. After transitioning to the non-connection mode, the terminal device receives the services within the multicast service set #1 based on the newly established MRB and the reserved MRB.

[0152] As can be seen in this way, compared with the case where the terminal device starts to acquire the MRB configuration in the non-connection mode after transitioning to the non-connection mode in the above-described method, in this embodiment, the time period of interruption of receiving the multicast service by the terminal device can be shortened, and the continuity of the multicast service can be improved.

[0153] Method 4:

[0154] The first information indicates the MRBs that need to be reserved or paused in the MRB used by the terminal device to receive services within the multicast service set #1 in the connection mode.

[0155] Optionally, the first information indicates the MBS session IDs of the multicast services received by the terminal device in the connection mode that need to be reserved or paused. As can be seen from the above, one MBS session can correspond to one or more MRBs. Therefore, the need to reserve or pause one MBS session implicitly indicates the need to reserve or pause the multiple MRBs corresponding to the MBS session.

[0156] Optionally, the first information indicates the G-RNTIs of the multicast services received by the terminal device in the connection mode that need to be reserved or paused. As can be seen from the above, one MRB corresponds to only one G-RNTI, but one G-RNTI can correspond to multiple MRBs. Therefore, the need to reserve or pause one G-RNTI implicitly indicates the need to reserve or pause one or more MRBs corresponding to the G-RNTI.

[0157] Optionally, the method further includes: The terminal device receives second information from the network device in the connected mode. Here, the second information instructs the terminal device to receive services within the multicast service set #1 in the non-connected mode. The terminal device migrates to the non-connected mode based on the RRC release message, and in the non-connected mode, the terminal device continues to receive services within the multicast service set #1 based on the second information by using the MRB (or MRB configuration) determined in S1203.

[0158] Optionally, the first information may be transmitted to the terminal device before the second information, or the first information and the second information may be transmitted to the terminal device simultaneously.

[0159] Optionally, the second information may be carried in an RRC release message transmitted by the network device to the terminal device. The RRC release message instructs the terminal device to migrate to the non-connected mode, and the second information indicates that the reason for the terminal device to release the RRC connection is for the terminal device to receive multicast services in the non-connected mode.

[0160] In the above-described embodiment, when the terminal device is released to the non-connected mode, the MRB configuration used to receive the multicast service is specified. Therefore, before being released to the non-connected mode, the terminal device may determine the MRB configuration used to receive the multicast service in the non-connected mode, thereby facilitating the continuity of the reception of the multicast service in the process of the UE being released to the non-connected mode.

[0161] When network congestion is alleviated (completely alleviated or alleviated to a certain extent), when a multicast service is enabled, or when it is necessary to cancel the multicast service, it can be understood that the network device can further call the terminal device that is released from the connected mode to receive the multicast service through the paging message and transition to the connected mode. After receiving the paging message, the terminal device performs access control, for example, performs UAC processing. When the terminal device is permitted to perform access, the terminal device starts the RRC connection control procedure and transitions to the RRC connected mode. However, for a terminal device that receives a multicast service in the RRC idle mode, after receiving the paging message, since the AC corresponding to the paging service becomes equal to 0, a plurality of terminal devices called by the paging message can directly execute the RRC connection control procedure. In this case, a large number of terminal devices may access the network simultaneously, causing network congestion.

[0162] From such a perspective, the present application provides another method for effectively solving the above-described technical problems. Hereinafter, the method provided in the present application will be described in detail.

[0163] FIG. 13 is a schematic flowchart showing another communication method according to the present application. This method includes the following steps.

[0164] S1301: The network device transmits a group paging message to the terminal device. In response, the terminal device receives the group paging message from the network device.

[0165] Optionally, the group paging message includes first information, and the first information is used to call a terminal device group to receive the first multicast service. Here, the terminal device group includes the terminal devices that receive the group paging message.

[0166] The terminal device group called through the first information is a terminal device that participates in the first multicast service and is in the non-connected mode, which should be understood.

[0167] S1302: Based on the first information and the second information, the terminal device performs at least one of the following. That is, receiving the first multicast service in the non-connected mode. Or, performing the RRC connection control procedure. The second information indicates whether the network device provides the first multicast service to the terminal device in the non-connected mode.

[0168] When the network device provides the first multicast service to the device in the non-connected mode, it should be understood that in the connected mode, only by participating in the first multicast service, the terminal device in the non-connected mode can receive the first multicast service. Therefore, it can be understood that the second information also indicates whether the network device provides the first multicast service to the called terminal device group in the non-connected mode.

[0169] Optionally, the second information may be carried in the group paging message, or the second information may be carried on the multicast control channel, or the second information may be carried in another message. This is not limited in this application. For example, both the first information and the second information are carried in the group paging message. The first information may be the TMGI of the first multicast service, and the second information may be 1-bit indication information. For example, 0 represents that the network device provides the first multicast service to the terminal device in the non-connected mode, 1 represents that the network device does not provide the first multicast service to the terminal device in the non-connected mode, and vice versa. As another example, the first information is carried in the group paging message, and the second information is carried on the multicast control channel.

[0170] For example, the multicast control channel may be a multicast control channel for multicast or a multicast control channel for multiplexed broadcast. This is not particularly limited in this application. In the present embodiment of this application, MCCH represents a multicast control channel, but it should be understood that MCCH does not need to constitute any limitation on the content and function of the channel. This application does not exclude the possibility of naming the multicast control channel by using another name. For example, the multicast control channel for multicast may continue to use the name MCCH of the multicast control channel for broadcast, or may use another name.

[0171] As can be understood from the above description, it should be understood that before executing the RRC connection control procedure, the terminal device usually needs to first execute an access control procedure. Hereinafter, with reference to FIGS. 14, 15, and 16, several possible implementations of S1302 are provided. For example, an example in which both the first information and the second information are carried in a group paging message is used for the following description.

[0172] FIG. 14 is a flowchart showing a first implementation. In this implementation, the terminal device determines whether to receive the first multicast service in the non-connection mode or execute the RRC connection control procedure based on the second information. This implementation may particularly include the following steps.

[0173] Step 1: The terminal device determines, based on the second information, whether the network device provides the first multicast service to the terminal device in the non-connection mode.

[0174] When second information indicates that, optionally, a network device provides a first multicast service to a terminal device in a non-connected mode, the terminal device does not execute an access control procedure nor a subsequent RRC connection control procedure, and the terminal device receives the first multicast service in the non-connected mode. When second information indicates that a network device provides a first multicast service to a terminal device in a non-connected mode, the terminal device may obtain configuration information of the first multicast service by monitoring a PDCCH corresponding to an MCCH, and it should be understood that the terminal device receives the first multicast service based on the obtained configuration information of the first multicast service.

[0175] When second information indicates that, optionally, a first multicast service used to be received by a terminal device in a non-connected mode is not provided, step 2 is executed.

[0176] When, optionally, a terminal device has a high priority or is an important terminal device or a specific terminal device indicated by a core network, the terminal device may ignore the second information, skip the access control procedure, and directly execute the RRC connection control procedure, or the terminal device may ignore the second information and execute the access control procedure, the terminal device is permitted to execute the access, and the terminal device continues to execute the RRC connection control procedure.

[0177] Step 2: The terminal device executes an access control procedure. Then, the terminal device executes step 3.

[0178] For example, the access control procedure may particularly be a UAC.

[0179] For example, the access control procedure can be further implemented in the following two ways. Method 1: The group paging message includes a set of prohibited parameters (which can be understood as a function and whose meaning or value range is equivalent to the prohibited parameters in step 4 of Concept Explanation 10). In this way, compared with the UAC procedure, the terminal device does not need to determine the AC, and based on the set of prohibited parameters provided in the group paging message, the terminal device can directly determine whether the terminal device is permitted to execute the access (i.e., it can execute step 3). Method 2: The group paging message includes an index corresponding to the set of prohibited parameters. In this way, the terminal device also does not need to determine the AC, and based on the index, it can directly determine the corresponding set of prohibited parameters (which can be understood as a function and whose meaning or value range is equivalent to the prohibited parameters in step 4 of Concept Explanation 10), and then the terminal device can determine whether the terminal device is permitted to execute the access (i.e., it can execute step 3).

[0180] Step 3: The terminal device determines whether the terminal device is permitted to execute the access.

[0181] Optionally, if the terminal device is permitted to execute the access, the terminal device executes the RRC connection control procedure.

[0182] Optionally, if the access of the terminal device is prohibited, the terminal device executes step 4.

[0183] For example, when the access control procedure is UAC, in the step of determining whether access is permitted in UAC, the terminal device may have the AC corresponding to the group paging service being the same as the AC of the existing paging service, that is, the AC is 0, or the AC of the paging service may be extended, whereby it is determined that the AC is not equal to 0. When the AC is equal to 0, the terminal device permits the execution of the access, and the terminal device executes the RRC connection control procedure. When the AC is not equal to 0, the terminal device may not be permitted to execute the access or the access may be prohibited.

[0184] For example, when the access control procedure is UAC and the AC is not equal to 0, but the network device expects that all terminal devices can directly access, that is, there is no terminal device whose access is prohibited, the prohibition parameter corresponding to the AC in the UAC parameter may be deleted from the SIB. In this way, when the terminal device cannot find the prohibition parameter corresponding to the AC, the terminal device directly accesses, whereby all terminal devices can directly access. Alternatively, a 100% ratio is introduced into the value of the prohibition coefficient of the AC of the group paging service, whereby all terminal devices can directly access. This method is improved based on the fact that the maximum value of the prohibition coefficient corresponding to the AC in the existing UAC parameter is 95% and not 100%.

[0185] For example, when the access control procedure is implemented in Method 1 or Method 2 in Step 2 and the network device expects that all terminal devices can directly access, the network device may not include a prohibition parameter in the paging message. In this way, when the terminal device cannot find the prohibition parameter, the terminal device directly accesses, whereby all terminal devices can directly access.

[0186] For example, if the network device expects that all terminal devices can directly execute access, the network device may more directly indicate that the called terminal device group is permitted to execute access.

[0187] Step 4: The terminal device determines a first duration based on the prohibited time in the prohibition parameter, and then starts a first timer. The execution time of the first timer is the first duration.

[0188] Before the first timer expires, the terminal device is prohibited from restarting the access control procedure. After the first timer expires, the terminal device executes Step 2, that is, executes the access control procedure again.

[0189] Optionally, the terminal device may continue to monitor the PDCCH of the MCCH within the execution time of the first timer to detect whether the network device provides the first multicast service to the terminal device in the non-connected mode. The reason for the terminal device to continue the monitoring when the access of the terminal device is prohibited is that when transmitting the second information, the network device may not provide the first multicast service to the terminal device in the non-connected mode, but after transmitting the second information, the network device may provide the first multicast service to the terminal device in the non-connected mode, which should be understood. For example, when the network device performs paging, there is no terminal device performing access. In this case, the network device regards that there is no terminal device that has performed access, and therefore does not provide the configuration information of the first multicast service in the non-connected mode. After the terminal device accesses normally, in order to reduce the simultaneous access of a large number of terminal devices in the same time period, the network device may start to provide the configuration information of the first multicast service in the non-connected mode. Therefore, when the access of the terminal device is prohibited, the terminal device that is prohibited from accessing may obtain the configuration information of the first multicast service within the execution time of the first timer through monitoring.

[0190] Optionally, when monitoring the PDCCH of MCCH within the execution time of the first timer, it can also be understood as another way for the network device to detect whether to provide the first multicast service to the terminal device in the non-connected mode, or for the terminal device to obtain the second information. Optionally, after the access of the terminal device is prohibited, whether the terminal device needs to execute the monitoring procedure can be controlled through the first indication information. For example, the first indication information may indicate whether the current cell supports the multicast service in the non-connected mode, or the first indication information may indicate whether the current cell has the multicast service in the non-connected mode, or the first indication information may indicate whether the current cell provides transmission for the service in the non-connected mode. For example, if the first indication information indicates that the current cell does not support the multicast service in the non-connected mode, the terminal device does not need to execute the above-described procedure. It should be understood that the current cell is the cell where the terminal device receives the group paging message, and the current cell is the cell that receives the service provided by the network device.

[0191] Optionally, the first indication information may be included in the SIB message, or when the terminal device is in the connected mode, the first indication information is carried in the dedicated signaling.

[0192] In this case, the terminal device may have several specific implementations according to whether the configuration information of the first multicast service is obtained through monitoring within the execution time of the first timer. These implementations are applicable to the other implementation procedures provided in S1302 of this application.

[0193] (1) If the configuration information of the first multicast service is obtained through monitoring within the execution time of the first timer, the terminal device receives the first multicast service in the non-connection mode and stops attempting to access the network device. Stopping the terminal device from attempting to access the network device can also be understood as the terminal device directly ending the access control procedure, or after the first timer expires, the terminal device stops starting the access control procedure, or the terminal device stops the first timer and stops starting the access control procedure.

[0194] It should be noted that when the timer that prohibits the access of the terminal device expires or stops, the case where the access of the terminal device is prohibited is released, that is, it is considered that the terminal device can start the next access control procedure.

[0195] (2) If the configuration information of the first multicast service is obtained through monitoring within the execution time of the first timer, the terminal device in the non-connection mode can receive the first multicast service, but without stopping the first timer, after the first timer expires, the access control procedure is restarted.

[0196] (3) If the configuration information of the first multicast service is not obtained through monitoring within the execution time of the first timer, the terminal device restarts the access control procedure after the first timer expires.

[0197] Optionally, within the execution time of the first timer, the terminal device may further monitor whether the MCCH includes wake-up information indicating that the MCCH wakes up the terminal device. Here, the wake-up information is used to enable the terminal device to transition from the non-connected mode to the connected mode. If the wake-up information is obtained through monitoring, the terminal device stops the first timer and executes step 2. If the wake-up information is not obtained through monitoring, after the first timer expires, the terminal device executes step 2. In a possible scenario, when the terminal device waits for another access within the first timer execution time and the current congestion of the network device is alleviated, some terminals that were prohibited from accessing may attempt another access. Therefore, the network device may include wake-up information in the MCCH. In this way, after receiving the wake-up information, the terminal device may stop the first timer and attempt another access. For example, the wake-up information may be explicitly indicated through the MCCH, or the wake-up information may be implicitly indicated through the TMGI of the first multicast service that does not exist in the TMGI list of the MCCH.

[0198] The first implementation shown in FIG. 14 can be used in various scenarios, such as the activation of a multicast service, the deactivation of a multicast service, the complete alleviation of network congestion, or the partial alleviation of network congestion. For example, the execution methods that can use the first implementation in various scenarios are as follows.

[0199] [1] Activation of a multicast service

[0200] It should be understood that the reason why the called terminal device is released to the non-connected mode in S1301 may be that the terminal device may receive a multicast service in the non-connected mode or the deactivation of RRC.

[0201] Optionally, in this scenario, if the second information indicates that the network device provides a multicast service to a terminal device in the disconnected mode, in the called terminal device group, regardless of whether the reason for the terminal device to be released from the disconnected mode is that the terminal device needs to receive the multicast service in the disconnected mode or the inactivation of RRC, the terminal device can remain in the disconnected mode and receive the multicast service based on the instruction of the second information.

[0202] Optionally, in this scenario, if the second information indicates that the network device does not provide a multicast service to a terminal device in the disconnected mode, the terminal device executes an access control procedure. In one implementation, in order to enable all the called terminal devices to access, the access control prohibition parameter can be set so that all the called terminal devices are permitted to access. For any possible specific setting method, refer to the description in step 3 in the embodiment in FIG. 14. Details are not described again in this specification.

[0203] Optionally, in this scenario, if the reason for the terminal device to be released from the disconnected mode is the inactivation of RRC, it can be stipulated that the terminal device ignores the second information and directly executes the RRC connection control procedure, or the terminal device ignores the second information and executes the access control procedure.

[0204] [2] Release of Multicast Service

[0205] In the scenario of canceling the multicast service, usually when the core network activates the cancellation of the multicast service, network devices do not provide the multicast service to terminal devices in the disconnected mode. In this case, the called terminal devices need to return to the connected mode as much as possible to receive the multicast service. Therefore, the network device may indicate through the second information that the network device does not provide the multicast service to terminal devices in the disconnected mode. In this case, the terminal device performs access control. In one implementation, the prohibited parameters of access control may be set so as to permit all the called terminal devices to access in order to enable all the called terminal devices to access. For the specific setting method, refer to the description in step 3 in the embodiment in FIG. 14. Details will not be described again in this specification.

[0206] [3] Relief of congestion (complete)

[0207] In the scenario where the congestion in the network device is completely relieved, the called terminal devices need to return to the connected mode as much as possible to receive the multicast service. Therefore, the network device may indicate through the second information that the network device does not provide the multicast service to terminal devices in the disconnected mode. In this way, the terminal device performs access control. For example, for the specific setting method to enable all the called terminal devices to access, refer to the description in step 3 in the embodiment in FIG. 14. Details will not be described again in this specification.

[0208] [4] Relief of congestion (partial)

[0209] When a network device has several resources that can be used to provide multicast services in the connection mode, some terminal devices in the called terminal device need to be controlled to access the network device. In this case, the network device further provides a multicast service to the called terminal device in the non-connection mode, so that it should be understood that the terminal device can receive the multicast service when the access of the terminal device is prohibited. Further, after the called terminal device receives a group paging message, when the network device provides a multicast service to the terminal device in the non-connection mode, if the called terminal device determines, it should be understood that the called terminal device continues to stay in the non-connection mode. Therefore, in this scenario, the network device can further provide a multicast service to the called terminal device in the non-connection mode, but the network device also needs to indicate through the second information that the network device does not provide a multicast service to the terminal device in the non-connection mode. Further, the terminal device also supports checking whether the MCCH has the configuration information of the multicast service within the duration of the timer when the access of the terminal device is prohibited. In this way, the terminal device in the non-connection mode executes the access control procedure. In this way, some terminal devices are permitted to execute access, and the access of some terminal devices is prohibited. The terminal device in the non-connection mode whose access is prohibited can obtain the MCCH and receive the multicast service when the access is prohibited.

[0210] Optionally, in this scenario, in the process of executing the access control procedure, the terminal device receives the multicast service without being paused and continuously monitors the PDCCH corresponding to the MCCH.

[0211] Optionally, a terminal device in a disconnected mode where access cannot be executed may continue to remain in the disconnected mode, may receive a multicast service, or may re-execute access control after the duration of a timer that prohibits access by the terminal device has expired.

[0212] FIG. 15 is a flowchart showing a second implementation. The difference from the procedure in FIG. 14 is that in this implementation, the terminal device first executes an access control procedure after receiving a group paging message, and determines subsequent steps based on second information after the terminal device is not permitted to execute access. This implementation may include the following steps.

[0213] Step 1: The terminal device executes an access control procedure. Then, the terminal device executes Step 2.

[0214] For a specific manner in which the access control procedure may be implemented, refer to the description in Step 2 in FIG. 14. Details will not be described again in this specification.

[0215] Optionally, if the terminal device has a high priority or is an important terminal device or a specific terminal device instructed by the core network, the terminal device may skip the access control procedure and directly execute the RRC connection control procedure, or the terminal device may execute the access control procedure, the terminal device is permitted to execute access, and the terminal device continues to execute the RRC connection control procedure.

[0216] Step 2: The terminal device determines whether the terminal device is permitted to execute access.

[0217] Optionally, if the terminal device is permitted to execute access, the terminal device executes an RRC connection resumption procedure or an RRC connection establishment procedure.

[0218] Optionally, when access to the terminal device is prohibited, after the access is prohibited, the terminal device needs to determine a second duration based on the prohibited time of the access control prohibition parameter. Here, the second duration is the execution time of the second timer.

[0219] Optionally, in this implementation, before determining whether to start the second timer, the terminal device first needs to execute step 3. For example, when the access control procedure is UAC, in the step of determining whether access is permitted in UAC, the terminal device may determine that the AC corresponding to the group paging service can be the same as the AC of the existing paging service, that is, the AC is 0, or the AC of the paging service can be extended, so that it is determined that the AC is not equal to 0. If the AC is equal to 0, the terminal device permits the execution of the access, and the terminal device executes the RRC connection control procedure. If the AC is not equal to 0, the terminal device may not be permitted to execute the access or the access may be prohibited.

[0220] For example, when the access control procedure is UAC and the network device wants to control so that none of the terminal devices are permitted to execute the access, the network device may extend the AC of the group paging service, so that the AC is not equal to 0, and then may set the prohibition coefficient of the prohibition parameter in the AC of the group paging to 0. In this way, none of the terminal devices are permitted to execute the access, and all terminal devices remain in the non-connected mode and receive the first multicast service.

[0221] For example, when the network device wants to control so that none of the terminal devices are permitted to execute the access, the network device may alternatively directly instruct the terminal device group that has been called to have the access prohibited.

[0222] Step 3: Based on the second piece of information, the terminal device determines whether the network device provides the first multicast service to the terminal device in the disconnected mode.

[0223] Optionally, if the second piece of information indicates that the network device provides the first multicast service to the terminal device in the disconnected mode, the terminal device does not start the second timer or ends the access control procedure (i.e., stops attempting to access the network device), and the terminal device monitors the PDCCH corresponding to the MCCH in the disconnected mode to obtain the configuration information of the first multicast service. Then, based on the obtained multicast configuration information in the first multicast service, the terminal device receives the first multicast service in the disconnected mode.

[0224] Optionally, if the second piece of information indicates that the network device does not provide the first multicast service to the terminal device in the disconnected mode, Step 4 is executed.

[0225] Step 4: The terminal device starts the second timer. Before the second timer expires, the terminal device is prohibited from restarting the access control procedure. After the second timer expires, Step 1 is executed, and the terminal device restarts the access control procedure.

[0226] Optionally, within the execution time of the second timer, the terminal device may monitor whether the network device provides the first multicast service to the terminal device in the disconnected mode. The actions that may be executed after the terminal device obtains or does not obtain the configuration information of the first multicast service through monitoring are shown in FIG. 15. For specific explanations, refer to the explanations in Step 4 in FIG. 14. Details are not described again in this specification.

[0227] Optionally, in this implementation, the terminal device can directly execute step 4 after step 2. Specifically, regardless of whether the second information indicates that the first multicast service is provided, the terminal device starts the second timer. If the second information indicates that the network device provides the first multicast service to the terminal device, the terminal device in the disconnected mode receives the first multicast service within the execution period of the second timer, and after the first timer expires, executes the access control procedure again. In this implementation, it should be understood that the order of step 3 does not need to constitute a limitation to this application. The terminal device can determine whether the network device provides the first multicast service to the terminal device in the disconnected mode based on the second information at any time after the terminal device receives the second information. For example, before step 1, it can be determined based on the second information whether the network device provides the first multicast service to the terminal device in the disconnected mode.

[0228] For example, for the second implementation corresponding to FIG. 15, possible execution methods in various scenarios are as follows.

[0229] [1] Activation of multicast service

[0230] It should be understood that the reason why the called terminal device is released from the disconnected mode in S1301 is that the terminal device may receive the multicast service in the disconnected mode or it may be deactivated.

[0231] Optionally, in this scenario, the access control procedure is executed first. If the second information indicates that the access of the terminal device is prohibited and the network device provides a multicast service to the terminal device in the disconnected mode, then, in the called terminal device, both the terminal device released due to the need to receive the multicast service in the disconnected mode and the terminal device released due to inactivation can remain in the disconnected mode based on the instruction of the second information in order to receive the multicast service.

[0232] Optionally, in this scenario, the access control procedure is executed first. If the second information indicates that the access of the terminal device is prohibited and the network device does not provide a multicast service to the terminal device in the disconnected mode, the terminal device executes the access control procedure. In one implementation, the prohibition parameter can be set to allow all the called terminal devices to access in order to enable all the called terminal devices to access. For the specific setting method, refer to the description in step 3 in FIG. 14. Details will not be described again in this specification.

[0233] Optionally, in this scenario, if the reason for the terminal device to be released from the disconnected mode is inactivation, it is also stipulated that the terminal device ignores the second information and directly executes the RRC connection control procedure, or the terminal device ignores the second information and executes the access control procedure.

[0234] [2] Release of Multicast Service

[0235] In the scenario of canceling the multicast service, it is necessary to ensure that the terminal device can access the network device as much as possible. Usually, when the core network activates the cancellation of the multicast service, the network device does not provide the multicast service to the terminal device in the disconnected mode. Therefore, when the multicast service is canceled, the second information may indicate that the network device does not provide the multicast service to the terminal device in the disconnected mode. In one implementation corresponding to FIG. 15, the terminal device first performs access control. If the access is denied, the access control procedure is executed again based on the instruction content of the second information. For example, in order to enable all terminal devices to access, the prohibition parameter may be set to allow all called terminal devices to access. For the specific setting method, refer to the description in step 3 in FIG. 14. Details will not be described again in this specification.

[0236] [3] Relief of congestion (complete)

[0237] When the congestion in the network device is completely relieved, the terminal device needs to return to the connected mode as much as possible to receive the multicast service. Therefore, in this scenario, all called terminal devices may be permitted to execute access during access control. For example, for the specific setting method to enable all called terminal devices to access, refer to the description in step 3 corresponding to FIG. 11. Details will not be described again in this specification.

[0238] [4] Relief of congestion (partial)

[0239] If a network device has several resources that can be used to provide multicast services in the connection mode, some of the terminal devices in the called terminal device need to be controlled to access the network device. In this scenario, if the network device configures appropriate prohibition parameters for access control for the terminal device, the desired effect can be achieved. For example, set the prohibition coefficient in the appropriate prohibition parameters to control the proportion of terminal devices allowed to execute access.

[0240] In this case, the network device further provides a multicast service to the called terminal device in the non-connection mode. Thus, it should be understood that the terminal device can receive the multicast service when the access of the terminal device is prohibited. In an implementation corresponding to FIG. 15, when the terminal device first executes the access control procedure after receiving the group paging message, some of the terminal devices are allowed to execute access, and some of the terminal devices are prohibited from accessing. Then, the terminal device in the non-connection mode where access is prohibited can determine whether to receive the multicast service or execute the RRC connection control procedure in the non-connection mode based on the instruction of the second information.

[0241] FIG. 16 is a flowchart showing a third implementation. In this implementation, the network device does not send the second information, that is, it implicitly indicates that the group paging message does not carry the second information and the network device does not provide the first multicast service to the terminal device in the non-connection mode. This implementation may include the following steps.

[0242] Step 1: When it is not indicated by the group paging message whether the first multicast service is provided to the terminal device in the non-connection mode (that is, when the second information does not exist in the group paging message), the terminal device executes the access control procedure. Then, the terminal device executes Step 2.

[0243] Optionally, if the terminal device has a high priority or is an important terminal device or a specific terminal device instructed by the core network, the terminal device may ignore the second information, skip the access control procedure, and directly execute the RRC connection control procedure, or the terminal device may ignore the second information and execute the access control procedure. The terminal device is permitted to perform the access, and the terminal device continues to execute the RRC connection control procedure.

[0244] Step 2: The terminal device determines whether the terminal device is permitted to perform the access.

[0245] Optionally, if the terminal device is permitted to perform the access, the terminal device executes the RRC connection control procedure.

[0246] Optionally, if the access of the terminal device is prohibited, the terminal device executes Step 3.

[0247] For example, when the access control procedure is UAC and the network device wants to control so that none of the terminal devices is permitted to perform the access, the network device may extend the AC of the group paging service, so that the AC does not become equal to 0, and then the inhibition coefficient of the inhibition parameter in the AC of the group paging may be set to 0. In this way, without any of the terminal devices being permitted to perform the access, the terminal devices remain in the non-connected mode and receive the first multicast service.

[0248] For example, when the access control procedure is UAC and the network device wants to control so that none of the terminal devices are permitted to execute access, the network device can extend the AC of the group paging service, whereby the AC is not made equal to 0, and then the inhibition coefficient of the inhibition parameter in the AC of the group paging can be set to 0. In this way, without any of the terminal devices being permitted to execute access, the terminal devices remain in the non-connected mode and receive the first multicast service.

[0249] Similarly, for example, when the access control procedure is implemented in Method 1 or Method 2 in Step 2 in FIG. 14 and the network device wants to control so that none of the terminal devices are permitted to execute access, the network device can set the inhibition coefficient in the set of inhibition parameters included in the paging message to 0. In this way, without any of the terminal devices being permitted to execute access, the terminal devices remain in the non-connected mode and receive the first multicast service.

[0250] For example, when the network device wants to control so that none of the terminal devices are permitted to execute access, alternatively, the network device can directly instruct the group of terminal devices to which access has been called to be prohibited.

[0251] Step 3: The terminal device determines a third duration based on the prohibition time of the access control prohibition parameter, and then the terminal device starts a third timer. The execution time of the third timer is the third duration.

[0252] It should be understood that the restart of the access control procedure is prohibited before the third timer expires. After the third timer expires, the terminal device executes Step 1, that is, executes the access control procedure again.

[0253] Optionally, within a third duration, the terminal device may monitor whether the network device provides a first multicast service to the terminal device in the disconnected mode. After the terminal device obtains or does not obtain the configuration information of the first multicast service through monitoring within a third timer, the actions that can be executed are shown in FIG. 16. For specific descriptions, please refer to the description in FIG. 14. Details will not be described again in this specification.

[0254] Regarding the third implementation shown in FIG. 16, possible execution methods in various scenarios are as follows.

[0255] [1] Activation of Multicast Service

[0256] Optionally, in this scenario, an access control procedure is first executed. If the access of the terminal device is prohibited, the terminal device decides to execute the access control procedure based on the case where the network device does not provide a multicast service to the terminal device in the disconnected mode. To enable all called terminal devices to access, the access control prohibition parameter can be set so that all called terminal devices are allowed to access. For the specific setting method, please refer to the description in step 3 in FIG. 14. Details will not be described again in this specification.

[0257] Optionally, in this scenario, if the reason for the terminal device to be released from the disconnected mode is invalidation, it may also be stipulated that the terminal device ignores the content implicitly indicated by the group paging message and directly executes the RRC connection control procedure or the access control procedure.

[0258] [2] Deactivation of Multicast Service

[0259] In the scenario of canceling the multicast service, it is necessary to ensure that the terminal device can access the network device as much as possible. Usually, when the core network activates the cancellation of the multicast service, the network device does not provide the multicast service to the terminal device in the non-connected mode. Therefore, when the group paging message is sent due to the cancellation of the multicast service, the second information in the group paging message may indicate that the network device does not provide the multicast service to the terminal device in the non-connected mode. In one implementation corresponding to FIG. 16, the terminal device first performs access control. If the access control is rejected, the terminal device monitors whether there is configuration information corresponding to the multicast service. For example, for a specific setting method to enable all terminal devices to access, refer to the description in step 3 of FIG. 14. Details will not be described again in this specification.

[0260] [3] Relief of congestion (complete)

[0261] When the congestion in the network device is completely relieved, the terminal device needs to return to the connected mode as much as possible to receive the multicast service. For example, in this scenario, for a specific setting method to enable all terminal devices to access, refer to the description in step 3 of FIG. 14. Details will not be described again in this specification.

[0262] [4] Relief of congestion (partial)

[0263] If the network device has some resources that can be used to provide the multicast service in the connected mode, some of the terminal devices in the called terminal device group need to be controlled to access the network device. In this scenario, if the network device configures appropriate prohibition parameters for access control for the terminal device, the desired effect can be achieved.

[0264] In this case, the network device further provides a multicast service to the called terminal device group in the disconnected mode, so that it should be understood that the terminal device can receive the multicast service when the access of the terminal device is prohibited. In one implementation corresponding to FIG. 16, when the terminal device executes determining UAC access after receiving the group paging message, some terminal devices are permitted to execute the access, and some terminal devices are prohibited from accessing. For example, a terminal device in the disconnected mode with access prohibited may then determine whether to receive the multicast service based on the PDCCH of the MCCH obtained through monitoring, or execute the RRC connection control procedure in the disconnected mode.

[0265] According to this embodiment, for the terminal device transitioning to the disconnected mode, the access control procedure is extended, so that some terminal devices can receive the multicast service in the disconnected mode, and some terminal devices transition to the connected mode to receive the multicast service, avoiding network congestion caused by simultaneous access of a large number of terminal devices and effectively managing the access of the terminal devices.

[0266] The above is provided by using an example where the first information and the second information are carried in the group paging message. Hereinafter, the above method will be continuously described by using an example where the first information and the second information are carried on the MCCH. This method includes the following steps.

[0267] S1801: The network device transmits the first information and the second information to the terminal device. Here, the first information and the second information are carried on the MCCH. Accordingly, the terminal device receives the first information and the second information from the network device. The first information is used to call a terminal device group to receive the first multicast service, and the terminal device group includes the terminal device that receives the first information. The second information indicates whether the network device provides the first multicast service to the terminal device in the disconnected mode.

[0268] Optionally, the first information on the MCCH can be understood as wake-up information in the first implementation of S1302.

[0269] S1802: Based on the first information and the second information, the terminal device performs at least one of the following. That is, the step of receiving the first multicast service in the disconnected mode. Or the step of performing the RRC connection control procedure.

[0270] For the detailed description of S1802, please refer to S1302. For details, it will not be described again in this specification.

[0271] As can be seen from the above description, it should be understood that before performing the RRC connection control procedure, the terminal device usually needs to first perform the access control procedure. With reference to FIGS. 14, 15, and 16, some possible implementations of S1802 will be described below.

[0272] FIG. 14 can also be regarded as a flowchart showing the first implementation of S1802. In this implementation, the terminal device determines whether to receive the first multicast service in the disconnected mode or perform the RRC connection control procedure based on the second information. This implementation may particularly include the following steps.

[0273] Step 1: Based on the second information, the terminal device determines whether the network device provides the first multicast service to the terminal device in the disconnected mode.

[0274] Step 2: The terminal device starts to execute the UAC access control procedure. Then, the terminal device executes Step 3.

[0275] Step 3: The terminal device determines whether the execution of access by the terminal device is permitted.

[0276] Optionally, if the execution of access by the terminal device is permitted, the terminal device executes the RRC connection control procedure.

[0277] Optionally, if the access by the terminal device is prohibited, the terminal device executes Step 4.

[0278] Step 4: Based on the prohibited time in the prohibition parameter, the terminal device determines the first duration, and then starts the first timer. The execution time of the first timer is the first duration. Before the first timer expires, the restart of the access control procedure is prohibited for the terminal device. After the first timer expires, the terminal device executes Step 2, that is, executes the access control procedure again.

[0279] For other descriptions of Steps 1 to 4 and the application of the implementation in various scenarios, refer to the description of FIG. 14 in S1302. Details are not described again in this specification.

[0280] FIG. 15 can also be regarded as a flowchart of the second implementation of S1802. The difference from the second implementation of S1802 is that in this implementation, after receiving the group paging message, the terminal device first executes the access control UAC procedure, and after the execution of access by the terminal device is not permitted, subsequent steps are determined based on the second information. This implementation may include the following steps.

[0281] Step 1: The terminal device starts to execute the access control procedure. Then, the terminal device executes Step 2.

[0282] Step 2: The terminal device determines whether the terminal device is permitted to execute the access.

[0283] Optionally, if the terminal device is permitted to execute the access, the terminal device executes the RRC connection control procedure.

[0284] Optionally, if the access of the terminal device is prohibited, after the access is prohibited, the terminal device needs to determine a second duration based on the prohibited time of the prohibition parameter. Here, the second duration is the execution time of the second timer. It should be noted that in this implementation, the terminal device needs to execute Step 3 first before determining whether to start the second timer.

[0285] Step 3: The terminal device determines whether the network device provides a first multicast service to the terminal device in the non-connection mode based on the second information.

[0286] Optionally, if the second information indicates that the network device provides a first multicast service to the terminal device in the non-connection mode, the terminal device monitors the PDCCH corresponding to the MCCH in the non-connection mode without starting the second timer to obtain the configuration information of the first multicast service. Then, the terminal device receives the first multicast service in the non-connection mode based on the obtained multicast configuration information in the first multicast service.

[0287] Optionally, if the second information indicates that the network device does not provide a first multicast service to the terminal device in the non-connection mode, Step 4 is executed.

[0288] Step 4: The terminal device starts a second timer. Before the second timer expires, the terminal device is prohibited from restarting the access control procedure. After the second timer expires, Step 1 is executed, and the terminal device restarts the access control procedure.

[0289] For other descriptions of Steps 1 to 4 and the application of the implementation in various scenarios, refer to the description of FIG. 15 in S1302. Details will not be described again in this specification.

[0290] FIG. 16 can also be regarded as a flowchart showing a third implementation of S1802. In this implementation, the network device does not transmit the second information, that is, in this method, the fact that the MCCH does not carry the second information implicitly indicates that the network device does not provide the first multicast service to the terminal device in the non-connected mode. This implementation may include the following steps.

[0291] Step 1: When the MCCH does not indicate whether to provide the first multicast service in the non-connected mode, the terminal device starts to execute the access control procedure. Then, the terminal device executes Step 2.

[0292] Step 2: The terminal device determines whether the terminal device is permitted to execute the access.

[0293] Optionally, when the terminal device is permitted to execute the access, the terminal device executes the RRC connection control procedure.

[0294] Optionally, when the access of the terminal device is prohibited, the terminal device executes Step 3.

[0295] Step 3: The terminal device determines a third duration based on the prohibited time of the access control prohibition parameter, and then the terminal device starts a third timer. The execution time of the third timer is the third duration.

[0296] It should be understood that the terminal device is prohibited from restarting the access control procedure before the third timer expires. After the third timer expires, the terminal device executes Step 1, that is, executes the access control procedure again.

[0297] For other descriptions of Steps 1 to 3 and the application of the implementation in various scenarios, refer to the description of FIG. 16 in S1302. Details will not be described again in this specification.

[0298] Optionally, the first information and the second information may be further separately carried in any one of the group paging message, unicast paging message, MCCH message, system message, and message (MSG 2 / 4 / B) in the random access procedure, or may be jointly carried in one of the above-mentioned messages. This is not limited in this application. For specific implementation procedures, refer to the above description. Details will not be described again in this specification.

[0299] It should be understood that the sequence numbers of the above-mentioned processes do not mean the execution order. The execution order in the process needs to be determined based on the functions and internal logics of the processes, and should not constitute any limitation to the implementation process of the embodiments of this application.

[0300] Furthermore, in various embodiments of this application, unless otherwise specified or there is no logical contradiction, the terms and / or descriptions in various embodiments are consistent and can be mutually referred to. It should be understood that the technical features in various embodiments can be combined based on their internal logical relationships to form new embodiments.

[0301] Furthermore, in some of the above-described embodiments, it should be understood that devices in existing network architectures are mainly used as an example for the purpose of explanation. It should be understood that the specific form of the device is not limited in the embodiments of the present application. For example, all devices that can implement the same function in the future are applicable to the embodiments of the present application.

[0302] In the embodiments of the method described above, it can also be understood that the methods and operations implemented by a device (such as a terminal device or a network device) can be implemented by components of the device (such as a chip or a circuit).

[0303] The above will be described in detail with reference to FIGS. 12 and 16 for the methods provided in the embodiments of the present application. The above methods are mainly described from the perspective of the interaction between terminal devices and network devices. To implement the above functions, it can be understood that the terminal device and the network device include corresponding hardware configurations and / or software modules for executing each function.

[0304] Those skilled in the art should recognize that the present application may be implemented by hardware or by a combination of hardware and computer software in combination with the example units and algorithm steps described in the embodiments disclosed herein. Whether a function is executed by hardware or by hardware driven by computer software depends on the specific application and the design constraints of the technical solution. Those skilled in the art may use various methods to implement the described functions for each specific application, but such implementation should not be considered as exceeding the scope of the present application.

[0305] Hereinafter, with reference to FIGS. 17 and 18, the communication device provided in the embodiments of the present application will be described in detail. It should be understood that the description of the device embodiments corresponds to the description of the method embodiments. Therefore, for the content that is not described in detail, please refer to the method embodiments. For the sake of brevity, some content will not be described again in this specification. In the embodiments of the present application, based on the above-described method examples, the terminal device or the network device can be divided into functional modules. For example, each functional module may be obtained through division based on each corresponding function, or two or more functions may be integrated into one processing module. The integrated module may be implemented in the form of hardware or in the form of a software functional module. It should be noted that in the present embodiment of the present application, the module division is an example and is merely a logical function division. In actual implementation, other division methods may be used. By using an example in which each functional module is obtained through division based on each corresponding function, the following description is provided.

[0306] FIG. 17 is a block diagram showing a communication device 1000 according to the present application.

[0307] In a possible design, the communication device 1000 includes a receiving unit 1100 and a processing unit 1200. The communication device 1000 can implement the steps or procedures executed by the terminal device in the above-described method embodiments, or the corresponding steps or procedures. For example, the communication device 1000 may be a terminal device, or a chip or circuit within the terminal device. The receiving unit 1100 is configured to execute the receiving-related operations in the terminal device in the above-described method embodiments, and the processing unit 1200 is configured to execute the processing-related operations in the terminal device in the above-described method embodiments.

[0308] In a possible implementation, the processing unit 1200 is such that the terminal device performs radio resource control ( RRC )When in the connected mode, the receiving unit 1100 is configured to participate in the multicast service and receive first information from the network device when the terminal device is in the RRC connected mode. Here, the first information indicates the multicast radio bearer ( MRB ) configuration, and the MRB configuration is the MRB configuration used by the terminal device to receive the multicast service in the RRC idle mode. And the processing unit 1200 is further configured to determine the MRB configuration based on the first information.

[0309] Optionally, the receiving unit 1100 is further configured to receive second information from the network device when the terminal device is in the RRC connected mode. Here, the second information indicates to the terminal device to receive the multicast service in the RRC idle mode. The processing unit 1200 is further configured to enable the terminal device to transition to the RRC idle mode. And the receiving unit 1100 is configured to receive the multicast service by using the MRB configuration when the terminal device is in the RRC idle mode.

[0310] Optionally, the first information is used to operate the terminal device to obtain the MRB configuration, and the processing unit 1200 is specifically configured to perform the following based on the first information. That is, the physical downlink control channel corresponding to the multicast control channel ( PDCCH ) is monitored. And the MRB configuration carried on the multicast control channel is determined.

[0311] Optionally, the first information instructs the terminal device to receive the multicast service by using the MRB configuration used by the terminal device to receive the multicast service in the RRC connected mode when the terminal device is in the RRC idle mode. And the processing unit 1200 is specifically configured to perform the following. That is, based on the first information, it is determined that the MRB configuration used by the receiving unit to receive the multicast service in the RRC connection mode is the MRB configuration.

[0312] In another possible implementation, the receiving unit 1100 is configured to receive a group paging message from a network device. Here, the group paging message includes the first information, and the first information is used to call a group of terminal devices to receive the first multicast service, and the group of terminal devices includes terminal devices. And the processing unit 1200 is configured to perform at least one of the following based on the first information and the second information. That is, the receiving unit is radio resource control ( RRC ) Enable receiving the first multicast service in the non-connection mode. Or, the processing unit executes an RRC connection control procedure. Here, the second information indicates whether the network device provides the first multicast service to a group of terminal devices in the RRC non-connection mode.

[0313] Optionally, when the second information indicates that the network device provides the first multicast service to a group of terminal devices in the RRC non-connection mode, the receiving unit 1100 receives the first multicast service when the terminal device is in the RRC non-connection mode. Or, when the second information indicates that the network device provides the first multicast service to a group of terminal devices in the RRC non-connection mode without the terminal device being permitted to access the network device, the processing unit 1200 starts an access control procedure based on the first information, and the receiving unit 1100 receives the first multicast service when the terminal device is in the RRC non-connection mode.

[0314] Optionally, when the second information indicates that the network device does not provide the first multicast service to the terminal device group in the RRC idle mode, the processing unit 1200 executes an RRC connection control procedure. Alternatively, the processing unit 1200 starts an access control procedure based on the first information. When the terminal device is permitted to access the network device, the processing unit 1200 executes an RRC connection control procedure.

[0315] Optionally, the processing unit 1200 is further configured to monitor a physical downlink control channel PDCCH corresponding to a multicast control channel to obtain second information within the execution time of a first timer. Here, the duration of the first timer is the duration that the terminal device needs to wait after it is no longer permitted to access the network device and before it restarts the access control procedure. Then, the processing unit 1200 is further configured to stop the first timer and / or stop the start of the access control procedure. Alternatively, the group paging message includes the second information, and the processing unit 1200 is further configured to skip the start of the first timer and / or stop the start of the access control procedure.

[0316] Optionally, the communication device 1000 further includes a transmission unit 1300. The transmission unit 1300 and the reception unit 1100 may be integrated into one transceiver unit and may have both a reception function and a transmission function. This is not limited in this specification.

[0317] Optionally, in one implementation where the communication device 1000 is a terminal device in an embodiment of the method, the transmission unit 1300 may be a transmitter, and the reception unit 1100 may be a receiver. Also, the receiver and the transmitter may be integrated into one transceiver. The processing unit 1200 may be a processing device.

[0318] The functions of the processing device may be implemented by hardware or by hardware that executes the corresponding software. For example, the processing device may include a memory and a processor. The memory is configured to store a computer program, and the processor reads and executes the computer program stored in the memory to enable the communication device 1000 to execute the operations and / or processes performed by the terminal device in the method embodiments. Optionally, the processing device may include only a processor, and the memory configured to store the computer program is disposed outside the processing device. The processor is connected to the memory via a circuit / wiring to read and execute the computer program stored in the memory. As another example, the processing device may be a chip or an integrated circuit.

[0319] Optionally, in one implementation where the communication device 1000 is a chip or an integrated circuit installed in the terminal device, the transmission unit 1300 and the reception unit 1100 may be a communication interface or an interface circuit. For example, the transmission unit 1300 is an output interface or an output circuit, and the reception unit 1100 is an input interface or an input circuit. The processing unit 1200 may be a processor or a microprocessor integrated on a chip or an integrated circuit. This is not limited in this specification.

[0320] In another possible design, the communication device 1000 includes a processing unit 1200 and a transmitting unit 1300. The communication device 1000 may implement the steps or procedures executed by the network device in the above-described method embodiments, or the corresponding steps or procedures. For example, the communication device 1000 may be a network device, or a chip or circuit within a network device. The processing unit 1200 is configured to execute the processing-related operations of the network device in the above-described method embodiments. The transmitting unit 1300 is configured to execute the reception-related operations of the network device in the above-described method embodiments.

[0321] In a possible implementation, the processing unit 1200 is configured to determine that the terminal device participates in the multicast service. Then, the transmitting unit 1300 is ( RRC ) configured to transmit first information to the terminal device in the connected mode. Here, the first information indicates the multicast radio bearer ( MRB ) configuration, and the MRB configuration is the MRB configuration used by the terminal device to receive the multicast service in the RRC idle mode.

[0322] Optionally, the transmitting unit 1300 is further configured to transmit second information to the terminal device. Here, the second information instructs the terminal device to migrate to the RRC idle mode and receive the multicast service.

[0323] Optionally, the processing unit 1200 is further configured to determine, for the MRB configuration to receive multicast services in the RRC connected mode, the MRB configuration used by the terminal device. And the transmitting unit 1300 is further configured to transmit first information to the terminal device in the connected mode. Here, the first information instructs the terminal device to receive the multicast service by using the MRB configuration used by the terminal device to receive the multicast service in the RRC connected mode when the terminal device is in the RRC idle mode.

[0324] Optionally, the apparatus 1000 further includes a receiving unit 1100. The receiving unit 1100 is configured to perform the receiving-related operations of the network device in the embodiments of the above-described method. The receiving unit 1100 is configured to receive first indication information from the core network device. Here, the first indication information indicates the priority of one or more terminal devices. And the processing unit 1200 is further configured to determine, based on the first indication information, the terminal devices that need to be released to the idle mode to receive the multicast service.

[0325] Optionally, the transmitting unit 1300 and the receiving unit 1100 may be integrated into one transceiver unit and have both receiving and transmitting functions. This is not limited in this specification.

[0326] In another possible implementation, the transmitting unit 1300 is configured to transmit a group paging message to the terminal device. Here, the group paging message includes the first information, and the first information is used to call the terminal device group to receive the first multicast service, and the terminal device group includes the terminal devices. Here, the transmitting unit 1300 is further configured to transmit second information to the terminal device. Here, the second information indicates whether the network device provides the first multicast service to the terminal device group in the radio resource control (RRC) idle mode.

[0327] Optionally, the second information is carried in a group paging message, or the second information is carried on a multicast control channel.

[0328] Optionally, communication device 1000 further includes a receiving unit 1100. The transmitting unit 1300 and the receiving unit 1100 may be integrated into one transceiver unit and may have both receiving and transmitting functions. This is not limited in this specification.

[0329] Optionally, in one implementation where communication device 1000 is a network device in a method embodiment, the transmitting unit 1300 may be a transmitter, and the receiving unit 1100 may be a receiver. Also, the receiver and the transmitter may be integrated into one transceiver. The processing unit 1200 may be a processing device.

[0330] The functions of the processing device may be implemented by hardware or by hardware that executes corresponding software. For example, the processing device may include a memory and a processor. The memory is configured to store a computer program, and the processor reads and executes the computer program stored in the memory to enable communication device 1000 to perform the operations and / or processes executed by a network device in a method embodiment. Optionally, the processing device may include only a processor, and the memory configured to store a computer program is disposed outside the processing device. The processor is connected to the memory via a circuit / wiring to read and execute the computer program stored in the memory. As another example, the processing device may be a chip or an integrated circuit.

[0331] In one implementation, where the communication device 1000 is optionally a chip or integrated circuit installed within a network device, the transmission unit 1300 and the reception unit 1100 may be communication interfaces or interface circuits. For example, the transmission unit 1300 is an output interface or output circuit, and the reception unit 1100 is an input interface or input circuit. The processing unit 1200 can be a processor or microprocessor integrated on the chip or integrated circuit. This is not limited in this specification.

[0332] FIG. 18 is a diagram showing the configuration of the communication device 10 according to the present application. The device 10 includes a processor 11. The processor 11 is coupled to a memory 12. The memory 12 is configured to store computer programs or instructions and / or data. The processor 11 is configured to perform the following. That is, execute the computer programs or instructions stored in the memory 12. Or read the data stored in the memory 12 and execute the methods in the embodiments of the methods described above.

[0333] Optionally, there is one or more processors 11.

[0334] Optionally, there is one or more memories 12.

[0335] Optionally, the memory 12 and the processor 11 are either integrated together or disposed separately.

[0336] Optionally, as shown in FIG. 18, the device 10 further includes a transceiver 13. The transceiver 13 is configured to receive and / or transmit signals. For example, the processor 11 is configured to control the transceiver 13 to receive and / or transmit signals.

[0337] In the solution, the device 10 is configured to implement the operations performed by the terminal device in the embodiments of the methods described above.

[0338] For example, the processor 11 executes a computer program or instructions stored in the memory 12 to implement related operations executed by the terminal device in the embodiments of the above-described method, for example, the method executed by the terminal device in the embodiments shown in FIG. 12 or FIG. 13.

[0339] In another solution, the apparatus 10 is configured to implement operations executed by the network device in the embodiments of the above-described method.

[0340] For example, the processor 11 executes a computer program or instructions stored in the memory 12 to implement related operations executed by the network device in the embodiments of the above-described method, for example, the method executed by the network device in the embodiments shown in FIG. 12 or FIG. 13.

[0341] Furthermore, the present application further provides a computer-readable storage medium. The computer-readable storage medium stores computer instructions. When the computer instructions are executed on a computer, the operations and / or procedures executed by the terminal device or the network device in the embodiments of the method of the present application are executed.

[0342] The present application further provides a computer program product. The computer program product includes computer program code or instructions. When the computer program code or instructions are executed on a computer, the operations and / or procedures executed by the terminal device or the network device in the embodiments of the method of the present application are executed.

[0343] In addition, this application further provides a chip. Here, the chip includes a processor. A memory configured to store a computer program is disposed independently of the chip. The processor is configured to execute the computer program stored in the memory, whereby the operations and / or processes executed by the terminal device or network device in any method embodiment are executed.

[0344] Furthermore, the chip may further include a communication interface. The communication interface may be an input / output interface, an interface circuit, or the like. Furthermore, the chip may further include a memory.

[0345] In addition, this application further provides a communication system. This communication system includes the terminal device and network device in the embodiments of this application.

[0346] The processor in the embodiments of the present application can be an integrated circuit chip, and it should be understood that it has signal processing capabilities. In the implementation process, each step of the embodiments of the above-described method can be completed by using the integrated logic circuit of the hardware in the processor or instructions in the form of software. The processor may be a central processing unit (CPU), or another general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or another programmable logic device, discrete gate or transistor logic device, discrete hardware component, or the like. The general-purpose processor may be a microprocessor, or the processor may be any conventional processor or the like. The steps of the method disclosed in the embodiments of the present application may be directly executed and completed by a hardware-encoded processor, or may be executed and completed by using a combination of the hardware in the encoded processor and a software module. The software module can be arranged in a mature storage medium in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or a register. The storage medium is arranged in the memory. The processor reads the information in the memory and completes the steps of the above-described method in combination with the hardware of the processor.

[0347] The memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include a volatile memory and a non-volatile memory. The non-volatile memory can be a read-only memory (ROM), a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), or a flash memory. The volatile memory can be a random access memory (RAM) used as an external cache. This is a non-limiting illustration, and as an example, many forms of RAM can be used. For example, static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchlink DRAM (SLDRAM), and direct rambus RAM (DR RAM), etc.

[0348] It should be noted that when the processor is a general-purpose processor, a DSP, an ASIC, an FPGA, or another programmable logic device, an individual gate, or a transistor logic device, or a discrete hardware component, the memory (storage module) can be integrated into the processor.

[0349] It should be further noted that the memory described in this specification is intended to include these memories and any other suitable types of memory, but is not limited thereto.

[0350] One skilled in the art can recognize that, in combination with the examples described in the embodiments disclosed herein, the units and algorithm steps can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether a function is executed by hardware or by software depends on the specific application and the design constraints of the technical solution. One skilled in the art may use different methods to implement the described functions for each specific application, but such implementation should not be regarded as exceeding the scope of this application. For the purpose of a convenient and simple description, regarding the detailed operation processes of the systems, devices, and units described above, it can be clearly understood by one skilled in the art to refer to the corresponding processes in the embodiments of the methods described above. Details will not be described again in this specification. In some embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the described embodiments of the device are merely examples. For example, the division into units is merely a logical function division, and in actual implementation, other divisions may be possible. For example, multiple units or components may be combined or integrated into another system, or some functions may be ignored or not executed. Furthermore, the shown or described mutual coupling, or direct coupling, or communication connection may be implemented through some interfaces. The indirect coupling or communication connection between devices or units may be implemented in an electrical form, a mechanical form, or another form. The units described as separate parts may or may not be physically separate, and the parts shown as units may or may not be physical units, or may be located in one position or distributed on multiple network units. Some or all of the units can be selected based on actual requirements to achieve the purpose of the solution of the embodiment.In addition, the functional units in the embodiments of the present application may be integrated into one processing unit, each unit may physically exist independently, or two or more units may be integrated into one unit. may also be 。

[0351] When the function is implemented in the form of a software functional unit and sold or used as an independent product, the function may be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present application may be implemented in the form of a software product. The computer software product is stored in a storage medium and contains several instructions for instructing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method described in the embodiments of the present application. The above-mentioned storage medium includes the following. That is, any medium that can store program code, such as a USB flash drive, a removable hard disk, a ROM, a RAM, a magnetic disk, or an optical disk.

[0352] It should be understood that the "one embodiment" referred to throughout this specification means that the specific features, structures, or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, the embodiments throughout this specification do not necessarily refer to the same embodiment. In addition, these specific features, configurations, or characteristics may be combined in one or more embodiments in any appropriate manner.

[0353] Furthermore, the ordinal numbers such as "first" and "second" in the embodiments of the present application are for distinguishing between a plurality of objects, but it should be understood that they do not limit the size, content, order, time series, priority, importance, or the like among the plurality of objects. For example, the first information and the second information do not indicate differences in the amount of information, content, priority, importance, or the like.

[0354] Furthermore, in this application, both "when" and "if" mean that the network element executes the corresponding process in an objective situation, and are not intended to limit time. It should be understood that the network element does not need to execute a decision action during implementation and does not mean any other arbitrary limitation.

[0355] Furthermore, in this application, it should be understood that "at least one" means one or more, and "a plurality" means two or more. "At least one item (part)" or similar expressions thereof refer to any combination of these items, including one item (part) or a plurality of items (parts), that is, any combination of a single item (part) or a plurality of items (parts). For example, at least one of a, b, or c represents a, b, c, a and b, a and c, b and c, or a and b and c.

[0356] Furthermore, unless otherwise specified, the same meaning as "the item includes one or more of the following, namely, A, B, and C" in this application usually means that the item can be any one of the following. That is, A. B. C. A and B. A and C. B and C. A, B, and C. A and A. A, A, and A. A, A, and B. A, A, and C. A, B, and B. A, C, and C. B and B, B, B, and B, B, B, and C, C and C, C, C, and C. And other combinations of A, B, and C. The above is an example using three elements A, B, and C to explain the optional items in the project. When the expression is "the item includes at least one of the following, namely, A, B,..., and X", that is, when there are more elements in the expression, the items applicable to the item can also be obtained according to the above rules.

[0357] Furthermore, it should be understood that the term "and / or" in the present application only describes the relationship between related objects and represents that three relationships can exist. For example, A and / or B can represent the following cases. That is, A exists alone, both A and B exist, and B exists alone. Here, A and B can be singular or plural. The character " / " generally indicates the relationship "or" between related objects. For example, A / B indicates A or B.

[0358] Furthermore, in the embodiments of the present application, it should be understood that "B corresponding to A" indicates that B is associated with A and B can be determined based on A. However, it should be further understood that determining B based on A does not mean that B is determined only based on A, and B can be determined based on A and / or other information.

[0359] The above description is only a specific implementation in the present application and does not limit the protection scope of the present application. Any modifications or alternatives that can be easily conceived by those skilled in the art within the technical scope disclosed in the present application shall fall within the protection scope of the present application. Therefore, the protection scope of the present application shall follow the protection scope of the claims.

Claims

1. A communication method, comprising: A step of receiving, by a terminal device in a radio resource control (RRC) non-connected mode, a group paging message from a network device, wherein the group paging message includes first information, and the first information is used to call a terminal device group to receive a first multicast service, and the terminal device group includes the terminal device; A step of, by the terminal device, based on the first information and second information, Receiving the first multicast service in the RRC non-connected mode, or Executing an RRC connection control procedure Wherein at least one of the steps is executed, and the second information indicates whether the network device provides the first multicast service to the terminal device group in the RRC non-connected mode; A method comprising the above.

2. The step of, by the terminal device, determining to receive the first multicast service in the RRC non-connected mode based on the first information and the second information includes: When the second information indicates that the network device provides the first multicast service to the terminal device group in the RRC non-connected mode, the step of, by the terminal device, receiving the first multicast service in the RRC non-connected mode, or The step of, by the terminal device, starting an access control procedure based on the first information; When the second information indicates that the network device provides the first multicast service to the terminal device group in the RRC non-connected mode and the terminal device is not permitted to access the network device, the step of, by the terminal device, receiving the first multicast service in the RRC non-connected mode The method according to claim 1, comprising

3. The step of executing, by the terminal device, an RRC connection control procedure based on the first information and the second information is When the second information indicates that the network device does not provide the first multicast service to the terminal device group in the RRC idle mode, the step of executing, by the terminal device, the RRC connection control procedure, or The step of starting, by the terminal device, an access control procedure based on the first information, and when the terminal device is permitted to access the network device, the step of executing, by the terminal device, the RRC connection control procedure The method according to claim 1, comprising

4. The second information is carried in the group paging message, or The second information is transmitted on a multicast control channel The method according to any one of claims 1 to 3

5. When the terminal device is not permitted to access the network device, the method is The step of monitoring, by the terminal device, a physical downlink control channel PDCCH corresponding to a multicast control channel within an execution time of a first timer to obtain the second information, wherein the execution time of the first timer is a duration that the terminal device needs to wait after the terminal device is not permitted to access the network device and before the terminal device restarts the access control procedure, and After the first timer expires, the step of ending, by the terminal device, the access control procedure or stopping, by the terminal device, the start of the access control procedure, or If the group paging message includes the second information, the terminal device either ends the access control procedure, or the terminal device skips starting the first timer, or after the first timer expires, the terminal device stops starting the access control procedure, where the execution time of the first timer is the duration that the terminal device needs to wait before restarting the access control procedure after the terminal device is not permitted to access the network device. The method according to claim 2, further comprising

6. A communication method A step of a network device transmitting a group paging message to a terminal device in a radio resource control (RRC) non-connection mode, where the group paging message includes first information, the first information is used to call a terminal device group to receive a first multicast service, and the terminal device group includes the terminal device. A step of the network device transmitting second information to the terminal device, where the second information indicates whether the network device provides the first multicast service to the terminal device group in the RRC non-connection mode. A method comprising

7. The second information is carried in the group paging message, or The second information is transmitted on a multicast control channel. The method according to claim 6.

8. A communication method When the terminal device is in a radio resource control (RRC) connection mode, a step of participating in a multicast service. When the terminal device is in the RRC connected mode, a step of receiving first information from a network device, where the first information indicates a multicast radio bearer (MRB) configuration, and the MRB configuration is an MRB configuration used by the terminal device to receive the multicast service in the RRC idle mode. A step of determining, by the terminal device, the MRB configuration based on the first information. A method comprising the above.

9. When the terminal device is in the RRC connected mode, a step of receiving second information from the network device, where the second information instructs the terminal device to receive the multicast service in the RRC idle mode. A step of the terminal device transitioning to the RRC idle mode. When the terminal device is in the RRC idle mode, a step of receiving the multicast service by using the MRB configuration. The method according to claim 8, further comprising the above.

10. The first information is used to cause the terminal device to acquire the MRB configuration, and the step of the terminal device determining the MRB configuration based on the first information A step of the terminal device monitoring a physical downlink control channel (PDCCH) corresponding to a multicast control channel based on the first information. A step of the terminal device determining the MRB configuration transmitted on the multicast control channel. The method according to claim 8 or 9, including the above.

11. When the first information is in the RRC idle mode, the terminal device receives the multicast service by using the MRB configuration used by the terminal device, and instructs the terminal device to receive the multicast service in the RRC connected mode. The step of determining the MRB configuration by the terminal device based on the first information is By the terminal device, based on the first information In the RRC connected mode, for receiving the multicast service, the step of determining that the MRB configuration used by the terminal device is the MRB configuration The method according to claim 8 or 9, comprising

12. A communication method The step of determining by the network device that the terminal device participates in the multicast service The step of transmitting, by the network device, first information to the terminal device in a radio resource control (RRC) connected mode, where the first information indicates a multicast radio bearer (MRB) configuration, and the MRB configuration is the MRB configuration used by the terminal device to receive the multicast service in the RRC idle mode A method comprising

13. The step of transmitting, by the network device, second information to the terminal device, where the second information instructs the terminal device to migrate to the RRC idle mode and receive the multicast service The method according to claim 12, further comprising

14. The first information is used to cause the terminal device to acquire the MRB configuration, and the method is The step of transmitting, by the network device, the MRB configuration to the terminal device, where the MRB configuration is carried by multicast control channel information The method according to claim 12 or 13, further comprising

15. The step of transmitting first information to the terminal device in the RRC connection mode by the network device comprises: The step of determining, by the network device, that the MRB configuration is the MRB configuration used by the terminal device to receive the multicast service in the RRC connection mode; and The step of transmitting the first information to the terminal device in the connection mode by the network device, wherein the first information instructs the terminal device to receive the multicast service by using the MRB configuration used by the terminal device to receive the multicast service in the RRC connection mode when the terminal device is in the RRC idle mode. The method according to claim 12 or 13, comprising

16. The step of receiving, by the network device, first indication information from a core network device, the first indication information indicating priorities of one or more terminal devices; and The step of determining, by the network device, a terminal device that needs to be released to the idle mode to receive the multicast service based on the first indication information The method according to any one of claims 12 to 15, further comprising

17. A communication device, comprising A receiving unit configured to receive a multicast service from a network device when a terminal device is in a radio resource control (RRC) connection mode When the receiving unit is in the RRC connected mode, the receiving unit is further configured to receive first information from the network device, where the first information indicates a multicast radio bearer (MRB) configuration, and the MRB configuration is an MRB configuration used by the terminal device to receive multicast services in the RRC idle mode. a processing unit configured to determine the MRB configuration based on the first information A communication device comprising:

18. When the receiving unit is in the RRC connected mode, the receiving unit is further configured to receive second information from the network device, where the second information instructs the terminal device to receive the multicast service in the RRC idle mode. The processing unit is further configured to enable the terminal device to transition to the RRC idle mode. When the receiving unit is in the RRC idle mode, the receiving unit is further configured to receive the multicast service by using the MRB configuration. The apparatus according to claim 17.

19. The first information is used to cause the terminal device to acquire the MRB configuration, and the processing unit monitors a physical downlink control channel (PDCCH) corresponding to a multicast control channel based on the first information, and determines the MRB configuration transmitted on the multicast control channel. is specifically configured to perform the above operations. The apparatus according to claim 17 or 18.

20. When the first information is in the RRC idle mode, in order for the terminal device to receive the multicast service in the RRC connected mode, by using the MRB configuration used by the terminal device, the terminal device is instructed to receive the multicast service, and the processing unit Based on the first information, it is determined that the MRB configuration used by the receiving unit to receive the multicast service in the RRC connected mode is the MRB configuration The apparatus according to claim 17 or 18, which is specifically configured to perform the above.

21. A communication device A transmitting unit configured to transmit a multicast service to a terminal device in a radio resource control (RRC) connected mode, The transmitting unit is further configured to transmit first information to the terminal device in the RRC connected mode, the first information indicating a multicast radio bearer (MRB) configuration, the MRB configuration being the MRB configuration used by the terminal device to receive the multicast service in the RRC idle mode. Communication device.

22. The transmitting unit is further configured to transmit second information to the terminal device, the second information instructing the terminal device to switch to the RRC idle mode and receive the multicast service. The apparatus according to claim 21.

23. The first information is used to cause the terminal device to acquire the MRB configuration, The transmitting unit is further configured to transmit the MRB configuration to the terminal device, the MRB configuration being transmitted on a multicast control channel. The apparatus according to claim 21 or 22.

24. A processing unit configured to determine that the MRB configuration is an MRB configuration used by the terminal device to receive the multicast service in the RRC connected mode further comprising The transmission unit is further configured to transmit the first information to the terminal device in the connected mode, where the first information is used by the terminal device to receive the multicast service in the RRC connected mode when the terminal device is in the RRC idle mode, and the first information is used to instruct the terminal device to receive the multicast service by using the MRB configuration used by the terminal device The apparatus according to claim 21 or 22. **Claim 25** A receiving unit configured to receive first indication information from a core network device, where the first indication information indicates the priority of one or more terminal devices further comprising The processing unit is further configured to determine, based on the first indication information, a terminal device that needs to be released to the idle mode to receive the multicast service The apparatus according to any one of claims 21 to 24. **Claim 26** A communication device A receiving unit configured to receive a group paging message from a network device, where the group paging message includes first information, the first information is used to call a terminal device group to receive a first multicast service, and the terminal device group includes a terminal device Based on the first information and second information Enabling the receiving unit to receive the first multicast service in the radio resource control (RRC) idle mode, or Executing an RRC connection control procedure by a processing unit A processing unit configured to execute at least one of the above, wherein the second information indicates whether the network device provides the first multicast service to the terminal device group in the RRC idle mode, and the processing unit A communication device comprising

27. When the second information indicates that the network device provides the first multicast service to the terminal device group in the RRC idle mode, the receiving unit receives the first multicast service when the terminal device is in the RRC idle mode, or The processing unit starts an access control procedure based on the first information, When the second information indicates that the network device provides the first multicast service to the terminal device group in the RRC idle mode without the terminal device being permitted to access the network device, the receiving unit receives the first multicast service when the terminal device is in the RRC idle mode. The device according to claim 26.

28. When the second information indicates that the network device does not provide the first multicast service to the terminal device group in the RRC idle mode, the processing unit executes an RRC connection control procedure, or The processing unit starts an access control procedure based on the first information, and when the terminal device is permitted to access the network device, the processing unit executes an RRC connection control procedure. The device according to claim 26.

29. The second information is carried in the group paging message, or the second information is transmitted on a multicast control channel. The device according to any one of claims 26 to 28.

30. The processing unit is further configured to monitor a physical downlink control channel PDCCH corresponding to a multicast control channel within an execution time of a first timer to obtain the second information, where the execution time of the first timer is a duration that the terminal device needs to wait before restarting the access control procedure after the terminal device is not permitted to access the network device, The processing unit is further configured to end the access control procedure or stop the start of the access control procedure by the terminal device after the first timer expires, or When the group paging message includes the second information, the processing unit is configured to end the access control procedure, skip the start of the first timer, or stop the start of the access control procedure after the first timer expires, and the execution time of the first timer is the duration that the terminal device needs to wait before restarting the access control procedure after the terminal device is not permitted to access the network device. The apparatus according to claim 27.

31. A communication device A transmission unit configured to transmit a group paging message to a terminal device, where the group paging message includes first information, the first information is used to call a terminal device group to receive a first multicast service, and the terminal device group includes the terminal device, The transmission unit is further configured to transmit second information to the terminal device, where the second information indicates whether the network device provides the first multicast service to the terminal device group in a radio resource control RRC non-connection mode. A communication device.

32. The apparatus according to claim 31, wherein the second information is carried in the group paging message or the second information is carried in a multicast control channel.

33. A communication device, comprising at least one processor and at least one memory, the at least one memory being configured to store a computer program or instructions, the at least one processor being configured to execute the computer program or the instructions in the memory to enable the method according to any one of claims 1 to 5 to be executed or to enable the method according to any one of claims 8 to 11 to be executed.

34. A communication device, comprising at least one processor and at least one memory, the at least one memory being configured to store a computer program or instructions, the at least one processor being configured to execute the computer program or the instructions in the memory to enable the method according to claim 6 or 7 to be executed or to enable the method according to any one of claims 12 to 16 to be executed.

35. A computer-readable storage medium storing computer instructions, wherein when the computer instructions are executed on a computer, the method according to any one of claims 1 to 5 is executed or the method according to any one of claims 8 to 11 is executed.

36. A computer-readable storage medium storing computer instructions, wherein when the computer instructions are executed on a computer, the method according to claim 6 or 7 is executed or the method according to any one of claims 12 to 16 is executed.

37. A computer program product, wherein the computer program product includes computer program code, and when the computer program code is executed on a computer, the method according to any one of claims 1 to 5 is executed, or the method according to any one of claims 8 to 11 is executed.

38. A computer program product, wherein the computer program product includes computer program code, and when the computer program code is executed on a computer, the method according to claim 6 or 7 is executed, or the method according to any one of claims 12 to 16 is executed.

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