A communication method includes: selecting an i.sup.th level user plane node corresponding to an i.sup.th level control plane node, i=1, . . . , N, N being a positive integer; transmitting a user plane MBS session establishment request to an i.sup.th level user plane node, and receiving a user plane MBS session establishment response fed back by the i.sup.th level user plane node; and transmitting an MBS session start request to a son control plane node of the i.sup.th level control plane node, so that the son control plane node allocates son user plane nodes to the i.sup.th level user plane node, the MBS session start request including identification information of the i.sup.th level user plane node and a first MBS Internet Protocol (IP) multicast transmission address and a first common-tunnel endpoint identifier (C-TEID) that are allocated by the i.sup.th level user plane node.

The disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. According to an embodiment of the disclosure, a method of controlling multicast and broadcast service (MBS) by a session management function (SMF) in a wireless communication system includes transmitting a first message including information about an MBS area and an MBS session identifier (ID) to an access and mobility management function (AMF), receiving a second message indicating that a user equipment receiving a service within the MBS area is located outside the MBS area from the AMF, determining that the UE is located outside the MBS area based on the second message, and processing a quality of service (QoS) flow applied to MBS traffic delivered by individual delivery.

A communication method and apparatus for a multicast broadcast service, a computer-readable storage medium, and an electronic device. The method includes: transmitting a first user plane multicast broadcast service (MBS) session establishment request to a first user plane node corresponding to an i.sup.th level control plane node, and receiving a first user plane MBS session establishment response fed back by the first user plane node, i=1, . . . , N; transmitting a second user plane MBS session establishment request to a second user plane node, and receiving a second user plane MBS session establishment response fed back by the second user plane node; and transmitting a first MBS session start request to a son control plane node of the i.sup.th level control plane node.

A handover method and a communication apparatus are provided. The method includes: A target access network device obtains a first message and information used for transmitting multicast data, where the first message is used for requesting to establish a resource for handing over a terminal device to the target access network device. The target access network device sends a second message, where the second message indicates the established resource on the target access network device; receives a first packet from a user plane network element, where the first packet corresponds to the information used for transmitting the multicast data; and sends the first packet to the terminal device. In this way, the terminal device is handed over from a source access network device to the target access network device when the terminal device receives the multicast data.

Embodiments of the present invention provide a method for mode switching and a device. The method includes: invoking a mode switch operation towards a second network function, where a parameter of the mode switch operation includes first information, and the first information includes a mode switch command; and the mode switch command is used to notify a target party to perform a mode switch operation.

Even when a radio terminal cannot receive content data from a base station to which the radio terminal serves, the radio terminal receives the content data from other base station. A wireless communication system (1) includes a plurality of radio base stations (21 to 23) and a radio terminal (40). The radio terminal (40) serves to a specific radio base station (serving radio base station) among the radio base stations (21 to 23). Moreover, the radio terminal (40) receives content data which is broadcasted or multicasted from a non-serving radio base station among the radio base stations (21 to 23) according to a gap pattern.

A method of processing state information relating to user equipment in a communications system comprising a radio access network, the method comprising: maintaining current state information relating to the user equipment; and on the basis of a change of connection of the user equipment from a first cell to a second cell: transmitting a current value associated with a given state information part to the target radio access node in response to detecting at least one of one or more predetermined triggers that indicate that the target radio access node may not have received the current value from the source radio access node; or relying on the target radio access node having received the current value from the source radio access node if said at least one of said one or more predetermined triggers is not detected.

A method and a base station for a mobile communications network. The base station includes a first transceiver configured to communicate over radio signals with a plurality of mobile terminals, in which the first transceiver configured to: transmit a first signal to serve a mobile terminal over multicast; receive from the mobile terminal information derived from the signal quality of a second signal received at the mobile terminal from a second transceiver; and receive from the mobile terminal further information on the quality of the first signal received at the mobile terminal from the first transceiver and on the quality of a third signal received at the mobile terminal from a third transceiver. The base station also includes a processor configured to, on the basis of a comparison of the quality of the second signal with a threshold, switch communications between the first transceiver and the mobile terminal from multicast to unicast; and on the basis of a comparison of the quality of the first signal and the quality of the third signal, instruct the mobile terminal to transition from being served by the first transceiver to being served by the third transceiver.

Methods, systems, and devices for wireless communications are described. A communication device, otherwise known as a user equipment (UE) may receive signaling indicating a set of multicast configurations for a set of multicast modes supported by the UE. Each multicast mode of the set of multicast modes may be associated with one or more radio resource control (RRC) states. The UE may determine a multicast configuration of the set of multicast configurations based on an RRC state according to which the UE is operating. The UE may receive, while operating according to the RRC state, multicast data according to the determined multicast configuration.

A base station for communication with a plurality of mobile terminals in a mobile communications network is disclosed. The base station includes a plurality of transmitters, in which each transmitter is configured to provide a transmit radio signal to a distinct space when compared to the other transmitters. A first transmitter is configured to provide to a first space, a transmit radio signal carrying a multicast service. A second transmitter is configured to provide to a second space, distinct from the first space, a transmit radio signal carrying a unicast service, and the second space shares a first boundary with the first space.