Abstract: A method, including sending, by a first network device, to a second network device, a first message requesting a context of a terminal device from the second network device, and receiving, by the first network device, a second message from the second network device, where the second message comprises first mobility history information and second mobility history information, where the first mobility history information is recorded by the terminal device, where the second mobility history information is recorded by a network device, and where the second message is a response message of the first message.

Abstract: A mobility optimization method and a related apparatus are provided. The method includes: determining connection failure information; and sending the connection failure information and an identifier of a first cell to a first network device by using a radio resource control (RRC) message, wherein the identifier of the first cell comprises an identifier of a cell from which a reconfiguration message or a handover command message received by the terminal device comes or an identifier of a cell in which a connection failure occurs, wherein the connection failure information is in a form of a container in the RRC message and the identifier of the first cell is outside the container.

Abstract: A communication method and a communication apparatus, the method including receiving first information from a network device, where the first information indicates, to a terminal device, to suspend a secondary cell group (SCG), suspending the SCG based on the first information, and changing a configuration parameter of a master cell group (MCG), where the configuration parameter comprises at least one of an available uplink transmission time period, a maximum transmit power, or a control channel blind detection parameter.

Abstract: A second network device receives, from a first network device, configuration information corresponding to at least one first reference signal and configuration information corresponding to at least one synchronization signal block, where the at least one synchronization signal block is at least one synchronization signal block corresponding to a synchronization signal block frequency; and the second network device determines timing information of the at least one first reference signal based on timing information of a reference synchronization signal block, where the reference synchronization signal block belongs to the at least one synchronization signal block.

Abstract: A terminal device obtains first information or second information, where the terminal device supports a first user identity and a second user identity, the first information includes information about a serving cell of the first user identity, and the second information includes a band combination list or a band list supported by the second user identity; and the terminal device sends the first information or the second information to a first access network device by using the second user identity, where the first access network device is an access network device accessed by the terminal device by using the second user identity.

Abstract: This application provides a communication method, a network device, and a terminal. The communication method includes: determining, by a first network device, at least one candidate target cell and first configuration information, where the first configuration information is used to trigger a terminal to determine one of the at least one candidate target cell as a to-be-handed-over-to cell; and sending, by the first network device, a first message to the terminal, where the first message includes first cell indication information and the first configuration information, and the first cell indication information is used to indicate the at least one candidate target cell.

Abstract: This application discloses a communications method. The method may include: receiving, by a receiving party, indication information sent by a first device, where the indication information is used to indicate at least one intermediate sequence number; receiving a data packet of the bearer sent by the first device; and skipping the at least one intermediate sequence number based on the indication information, deciphering, by using the old key, a data packet that is located on the bearer and whose sequence number is followed by the at least one intermediate sequence number, and deciphering, by using the new key, a data packet that is located on the bearer and whose sequence number follows the at least one intermediate sequence number.

Abstract: A communication method and apparatus, the method including performing, by a terminal device or a chip of the terminal device, sending a master cell group (MCG) failure message to a master node (MN) via a secondary node (SN) in response to detecting that a wireless connection fails, and further in response to a secondary cell group (SCG) not failing, performing cell selection in response to the SCG failing, and accessing a target cell in response to the target cell being a candidate cell pre-configured by the MN, where the target cell is a cell selected by the terminal device during the cell selection, where the SCG is a group of cells associated with the SN, and where the MCG is a group of cells associated with the MN.

Abstract: This application provides a paging method and apparatus. The paging method may be applied to a terminal device including a first subscriber identity and a second subscriber identity, where the first subscriber identity corresponds to a first paging occasion, and the second subscriber identity corresponds to a second paging occasion. The method includes: First, the terminal device determines that a paging occasion collision occurs between the first paging occasion and the second paging occasion, and then the terminal device notifies a first access network device that the paging occasion collision occurs, where the first access network device corresponds to a first cell in which the terminal device is located by using the first subscriber identity.

Abstract: A wireless communication method and apparatus. The method includes sending, with a first subscriber identity a first message to a first access network device, the first message requesting establishment or resumption of a second radio resource control (RRC) connection with the second subscriber identity, the first message including auxiliary information indicating to determine to release or deactivate a first RRC connection established with the first subscriber identity, and the second RRC connection being a connection established with the second subscriber identity, and receiving, with the first subscriber identity, a second message from the first access network device and that indicates to release or deactivate the first RRC connection, where the terminal device is in an RRC connected state with the first subscriber identity and in an RRC idle state or an RRC deactivated state with the second subscriber identity.

Abstract: This application provides a method for quality of experience QOE measurement and a communication apparatus. A network device configures configuration information for QOE measurement for a terminal device when signal quality is lower than a specific threshold. In addition, the terminal device may also perform QOE measurement or report a measurement result when the quality is lower than the specific threshold.

Abstract: This application provides a communication method and apparatus. The method includes: A terminal device receives indication information from a master node, where the indication information indicates that a key used for signaling transmission performed between the terminal device and a first secondary node by using a second SRB is a first key, the first key is a key used for signaling transmission performed between the terminal device and the master node by using a first SRB, and the first secondary node and the master node share one CU. In a scenario in which the master node and a secondary node share one CU, the terminal device determines that a key for signaling transmission performed between the terminal device and the secondary node is the same as a key for signaling transmission performed between the terminal device and the master node, which avoids complexity.

Abstract: Embodiments of this application provide a communication method and a communications system. The method includes: receiving, by a second network device from a first network device, information used to indicate that a terminal initiates a radio access network notification area update (RNAU), generating, by the second network device based on the information, a radio resource control release message on which security protection has been performed, and sending, to the first network device, the radio resource control release message on which the security protection has been performed.

Abstract: A data transmission method includes: receiving, by a user equipment (UE), first indication information from a wireless access device, where the first indication information is activation indication information or deactivation indication information; and when the first indication information is the activation indication information, executing, by the UE, a processing operation; or when the first indication information is the deactivation indication information, stopping, by the UE, the processing operation; where the processing operation includes at least one of a duplication operation and a switching operation; the duplication operation means transmitting same data through a plurality of links; and the switching operation means selecting one from a plurality of links to perform data transmission.

Abstract: A communication method and a related device, the method including receiving a radio access capability of a terminal device, detecting whether a target radio access capability the same as the received radio access capability of the terminal device exists in a terminal device access capability set, where the terminal device access capability set is a set of radio access capability information corresponding to radio access capabilities, and, when the target radio access capability exists in the terminal device access capability set, indexing second access capability indication information in a context of the terminal device to radio access capability information corresponding to the target radio access capability.

Abstract: In a method, a first band combination set reported by a terminal device may include a first band combination and a second band combination, the first band combination is a fallback band combination that has a same capability as the second band combination, and the first band combination and the second band combination correspond to different radio access technology types.

Abstract: The present disclosure relates to measurement methods and apparatus. In one example method, a terminal device receives N synchronization signal/physical broadcast channel block measurement timing configurations (SMTCs) from a network device. The terminal device obtains M measurement gaps based on M SMTCs in the N SMTCs respectively, where N and M are positive integers, and M is less than or equal to N.

Abstract: Embodiments of this application provide a synchronization signal/physical broadcast channel block (SSB) measurement method and an apparatus. One example method includes that a terminal device receives first information and second information. The first information indicates a time domain position of an SSB sent by a serving cell, and the second information indicates a set of SSBs that the terminal device needs to measure and that are sent by a neighboring cell. The terminal device measures, in a first measurement window based on the first information, the SSB sent by the serving cell. The terminal device measures, in a second measurement window based on the second information, the SSB sent by the neighboring cell.

Abstract: A communication method and apparatus, the method including obtaining, by a master access network device, handover triggering condition information of one or more cells corresponding to at least one candidate secondary access network device, sending a first message to a terminal device, where the first message comprises the handover triggering condition information, and receiving a first response message from the terminal device, where the first response message is used to indicate a cell identifier of a second cell corresponding to a second secondary access network device in the at least one candidate secondary access network device, and the second cell meets a handover triggering condition indicated by handover triggering condition information of the second cell.

Abstract: Example cell measurement methods and apparatus are described. One example method includes obtaining, by a first network device, a first paging parameter of a cell served by a second network device. The first paging parameter is used to indicate a first time domain position at which a terminal device monitors a paging message from the second network device. The first network device sends a reference signal based on the first paging parameter. A time domain position of the reference signal is determined based on the first time domain position.