Abstract: A communication method includes receiving a capability query message from a network device. The communication method also includes reporting capability information of a terminal device to the network device. The capability information includes an indication information set of N band set pairs, where N is a positive integer. Each piece of indication information in the indication information set is associated with one band set pair. The indication information indicates switching of a transmission branch performed by the terminal device between two band sets in the band set pair. The band set includes at least one of L bands in the band set pair, where L is an integer greater than or equal to 3.

Abstract: Embodiments of this application provide a communication method and a communication apparatus. The method includes: A terminal device receives first information, where the first information is related to a status of a first multicast service, and/or the first information is related to configuration information of the first multicast service in a second cell. The terminal device determines, based on the first information, whether to send first request information to the second cell, where the first request information is used by the terminal device to establish or resume an RRC connection. The terminal device is a terminal device that receives the first multicast service, the terminal device is a terminal device in a radio resource control RRC non-connected state, and the terminal device is a terminal device that performs handover or reselection from the first cell to the second cell.

Abstract: A communication method and apparatus are provided, so that an access network device can configure an initial hyper frame number (HFN) and a reference sequence number (SN) for a terminal device in time when no data packet is received from a core network device. The method includes: A first core network device obtains an initial multicast/broadcast service (MBS) quality of service flow identifier (QFI) SN corresponding to a first MBS session, and sends the initial MBS QFI SN in a first procedure. The first procedure is a procedure before a the 1st data packet of the first MBS session is sent to an access network device. After receiving the initial MBS QFI SN in the first procedure, the access network device may determine an initial HFN and a reference SN based on the initial MBS QFI SN, and send the initial HFN and the reference SN to a terminal device.

Abstract: A communication method and apparatus are provided, relate to the field of communication technologies, and are used to alleviate a problem of how to set a PDCP window variable when a terminal device performs packet data convergence protocol PDCP entity suspending or PDCP entity re-establishment. The method may include: The terminal device receives, from a network device, first information indicating packet data convergence protocol PDCP suspending, and sets, to an initial value, a PDCP window variable associated with a radio bearer RB other than a first RB. The first RB may include a multicast and broadcast service radio bearer MRB.

Abstract: A communication method, apparatus, and system are provided. The method may include: A terminal apparatus determines first indication information, where the first indication information indicates a status of a multicast/broadcast service, and the status of the multicast/broadcast service includes an inactive state; and the terminal apparatus stops, based on the first indication information, using a first radio network temporary identifier to monitor a physical downlink control channel corresponding to a multicast broadcast traffic channel. In the method, a network apparatus indicates the status of the multicast/broadcast service to the terminal apparatus. When determining that the status of the multicast/broadcast service is inactive, the terminal apparatus may not monitor the physical downlink control channel corresponding to the multicast broadcast traffic channel. This reduces power consumption of the terminal apparatus.

Abstract: A communication method and a communication apparatus are disclosed. The method includes: For a terminal device that enters a non-connected mode, when a network device pages the terminal device to receive a first multicast service, the network device may further indicate whether to provide the first multicast service for the terminal device in an RRC non-connected mode. The terminal device may perform at least one of the following based on the paging and indication of the network device: receiving the first multicast service in the RRC non-connected mode; or performing an RRC connection control procedure. According to the method, network congestion caused by simultaneous access of a large quantity of terminal devices can be avoided, and access of the terminal devices can be effectively managed.

Abstract: A mobility management method and an apparatus can improve continuity of a multicast service of a terminal device. The method includes: A source access network device sends, to a target access network device, a first message for requesting to hand over a first multicast service of a first terminal device to a first target cell, and the target access network device sends a second message to the source access network device as a response to the first message, where the second message includes first information indicating a first candidate cell, and the first candidate cell is a cell that provides a multicast service for a terminal device in an RRC non-connected mode. After receiving the second message, the source access network device sends, to the first terminal device, third information indicating a second candidate cell.

Abstract: A terminal device receives a SIB of a SCell, where the SIB includes information used for obtaining an MCCH configuration of an MBS; and sends an MII message, where the MII message carries an identifier of an MBS service of interest to the terminal device. In this way, in some embodiments, for example, in a scenario in which the secondary cell can provide a broadcast service, the terminal device may report, based on the received SIB of the SCell, the identifier of the MBS service of interest to the terminal device.

Abstract: This application provides a communication method and an apparatus. The method is applied to a terminal device. The terminal device includes a first multicast radio bearer MRB, the first MRB includes a first packet data convergence protocol PDCP entity and a first RLC entity, and the first RLC entity uses an acknowledged mode AM. The method includes: The terminal device receives first indication information sent by a source node, where the first indication information indicates to adjust a receive window of the first PDCP entity when the first PDCP entity is re-established; and the terminal device adjusts the receive window of the first PDCP entity based on the first indication information.

Abstract: Embodiments of this application provide a communication method and a communication apparatus. In this application, a terminal device receives a preconfigured measurement gap MG indicated by a network device and MG status information corresponding to each CC in at least one CC after the CC is deactivated. The MG status information is activated or deactivated. In a case that M CCs in the at least one CC are deactivated, the terminal device activates or deactivates the MG based on M pieces of MG status information corresponding to the M deactivated CCs, so that the terminal device can accurately determine, based on the MG status information of the deactivated CC, whether to activate or deactivate a preconfigured MG.

Abstract: A communication method and apparatus, to improve performance of a harmonized communication and sensing technology. The method includes: executing a first sensing task; determining that the first sensing task is to be switched; and sending first information to a second network device, where the first information is used for requesting to switch the first sensing task to another network device, and the second network device is configured to manage a plurality of network devices including a first network device. When the first network device that executes a sensing task determines that the sensing task needs to be switched to the another network device, the first information is used for triggering the second network device to select an appropriate network device to execute the sensing task, so that interruption duration of the sensing task can be reduced, continuity of the sensing task can be improved.

Abstract: A method includes: determining capability information, and sending the capability information to an access network device, where the capability information indicates a multicast service receiving capability corresponding to a band, and/or a multicast service receiving capability corresponding to a component carrier. The capability information indicates a multicast service capability at a band level or a component carrier level.

Abstract: This application provides a communication method and apparatus, to improve performance of a sensing technology. The method includes: sending a sensing signal in response to a sensing request from a first device, and receiving an echo signal of the sensing signal, where the sensing request carries at least one of the following: a sensing data type, sensing configuration information, access network device identifier information, a sensing requirement, and a sensing service identifier; and after the echo signal is received, sending a sensing result to the first device, where the sensing result includes sensing data determined based on the echo signal. Triggering, configuration, execution, processing, reporting, and other functions of a sensing function may be implemented through interaction between the first device and a first access network device.

Abstract: A communication method includes: obtaining first information from a first core network device, where the first information is used to request to add a first terminal device to a multicast service session corresponding to a first multicast service; and adding the first terminal device to a multicast service session corresponding to a second multicast service when a first condition is met, where the first condition includes that the first multicast service and the second multicast service are a same multicast service, and the second multicast service is provided by a second core network device. The first terminal device is added to the multicast service session corresponding to the second multicast service, so that service data of the second multicast service can be simultaneously provided for terminal devices in two networks by using an established resource related to the second multicast service.

Abstract: This application provides a session setup method and an apparatus. The method includes: when an access network device obtains a first session setup request from a first core network device, if the access network device determines that a multicast broadcast service corresponding to a first session that the first session request requests to set up is the same as a multicast broadcast service corresponding to a second session, determining that an air interface resource corresponding to the first session is the same as an air interface resource corresponding to the second session, where the first session setup request is used to request to set up the first session corresponding to a first multicast broadcast service, and the second session is a session set up between the access network device and a second core network device.

Abstract: A communication method and apparatus are provided. The method includes: A first node determines a sending time point of a second PDCP PDU based on first sending status information from a second node, where the first sending status information is associated with a first PDCP PDU, so that the first node can adjust the sending time point of the second PDCP PDU based on a sending situation of the first PDCP PDU, to avoid too many packet losses caused when a MAC PDU of the second PDCP PDU is not completely sent in a timely manner due to splitting and concatenation, so as to improve reliability of a synchronous data transmission mechanism in an NR system, and improve resource utilization.

Abstract: Data transmission methods and apparatuses, relate to the field of communications technologies are described. In an example method, a distributed unit (DU) receives a first packet data convergence protocol (PDCP) packet data unit (PDU) from a central unit (CU), where the first PDCP PDU carries data of a multicast broadcast service (MBS). The DU sends the first PDCP PDU to at least two terminal devices. The DU sends a status report to the CU, where the status report indicates results of sending the first PDCP PDU to the at least two terminal devices.