Abstract: This application provides a method, includes: receiving a second message from a second network node, wherein the second message comprises identification information of a terminal device, and wherein the identification information of the terminal device is in association with context information of the terminal device that is stored at a first network node; retrieving based on the identification information of the terminal device, the context information of the terminal device stored at the first network node; and, replacing the original cell radio network temporary identifier with a new cell radio network temporary identifier allocated by the first network node for the context information of the terminal device.

Abstract: This application provides a random access method and a communication apparatus. The method includes: receiving, by a terminal device, a response message from a network device; determining, by the terminal device, a message format of the response message, where the message format includes a first format or a second format; and parsing, by the terminal device, the response message based on the determined message format, where the response message in the first format includes a contention resolution identity and a control plane message; and the response message in the second format includes a contention resolution identity and includes no control plane message. A two-step random access method provided in this application includes two message formats of a random access response.

Abstract: Embodiments of this application provide a configuration method and apparatus. When indicating, by using an RRC connection release message, a terminal to enter an inactive state from a connected state, a network device may include, in the RRC connection release message, a configuration parameter allocated to the terminal in the inactive state. That is, the terminal receives the radio resource control RRC connection release message sent by the network device, where the RRC connection release message includes first information used to indicate a target configuration parameter. In this way, the terminal may enter the inactive state based on the RRC connection release message, and determine a context parameter of the inactive state based on the first information, so that the configuration parameter is properly allocated to the terminal in the inactive state.

Abstract: A signal transmission method includes receiving configuration information from a network device. The configuration information is used to indicate a serving cell that is allowed or forbidden to be used by a terminal for a first service or first control information. The method also includes adjusting the serving cell that is allowed or forbidden to be used by the terminal for the first service or the first control information. The method further includes transmitting the first service or the first control information by using an adjusted serving cell.

Abstract: This application provides a communication method and apparatus, and relates to the field of communication technologies, to resolve problems of a long data transmission delay and high signaling overheads. A first access network device receives uplink user plane data from a user equipment in an inactive state, and sends an uplink control plane information element and the uplink user plane data to a second access network device through a same interface. The method is applied to a data transmission process.

Abstract: This application provides a method for processing timing advance (TA) of a terminal, and an apparatus. A terminal obtains a correspondence between first TA and a beam, determines, based on the correspondence, the beam corresponding to the first TA, and further determines, based on the beam corresponding to the first TA, whether the first TA is invalid. According to this application, the terminal may determine, by using a finer granularity, whether the first TA is invalid, and this helps trigger selection of more appropriate TA, thereby further reducing interference between uplink transmission.

Abstract: This application discloses a communication method and apparatus. The method includes: A terminal device receives, in a first cell, configuration information of at least one candidate cell from an access network device; and selects a second cell when a radio link of the first cell meets a first condition (that is, a problem occurs on the radio link of the first cell). If the second cell belongs to the at least one candidate cell, the terminal device is handed over from the first cell to the second cell, and communicates with the access network device in the second cell based on configuration information of the second cell.

Abstract: This application provides a method, includes: a first network node sends an inactivity timer of a terminal device to a second network node, the first network node receives an inactive state indication of the terminal device from the second network node, wherein the inactive state indication of the terminal device is used by the first network node to determine whether the terminal device to enter an inactive state, the first network node notifies the second network node that the terminal device enters the inactive state.

Abstract: This application provides a data transmission method and apparatus. A terminal: receives a first uplink grant from a network device; sends first uplink data in to-be-sent data to the network device by using the first uplink grant; receives a second uplink grant from the network device; and sends second uplink data to the network device by using the second uplink grant, where the second uplink data is at least a part of uplink data in the to-be-sent data except the first uplink data, where the terminal is in a first state, and where the first state includes an idle state or an inactive state. The embodiments of this application help reduce a latency in a data transmission process.

Abstract: This application provides a random access method and a communications apparatus. The method includes: determining at least one random access preamble from at least one 2-step random access preamble, or determining one type of random access preamble from at least one 2-step random access preamble and at least one 4-step random access preamble, and performing random access by using the determined random access preamble. According to the application, the terminal device can determine a type of random access to be performed, thereby reducing an access latency.

Abstract: A method includes: triggering, by a terminal device, a scheduling request (SR); in response to determining that a physical uplink control channel (PUCCH) carrying the SR and a physical uplink shared channel (PUSCH) carrying a first data packet overlap in time domain of a first uplink resource and a processing status of the PUSCH on the first uplink resource is processing completed, sending, based on the processing status of the PUSCH on the first uplink resource, the PUCCH on an overlapping time domain resource. According to the method, when the PUCCH carrying the SR and the PUSCH overlap in time domain of the first uplink resource, the terminal device considers the processing status of the PUSCH on the first uplink resource, and may determine, based on the processing status of the PUSCH on the first uplink resource, to send the PUCCH or the PUSCH on the overlapping time domain resource.

Abstract: A random access method is provided including: a terminal side device obtains first uplink data from a first message buffer, wherein the first message buffer is a buffer specific to a first random access procedure, the first random access procedure is a procedure in which the terminal side device sends a first random access request, sends the first uplink data on a first uplink resource, and receives response information, and the response information is a first random access response to the first random access request or a response to the first uplink data. The terminal side device sends the first random access request to a network side device, and sends the first uplink data to the network side device on the first uplink resource. The terminal side device detects downlink control information, wherein the downlink control information indicates a resource of the response information.

Abstract: An entity establishment processing method and an apparatus are provided. The processing method includes: A terminal side device receives first indication information from a first network side device, where the first indication information is used to trigger reestablishment of a first PDCP entity of the terminal side device. When a first bearer corresponding to the first PDCP entity is not a radio bearer used to perform duplication transmission between the terminal side device and a core network side device, in a process in which the terminal side device reestablishes the first PDCP entity based on the first indication information, the terminal side device sets a parameter of the first PDCP entity to an initial value.

Abstract: The present disclosure relates to time synchronization methods and apparatus. In one example method, a terminal receives a system information block (SIB) sent by a distributed unit (DU), where the SIB is generated by the DU, the SIB includes time information, and the time information indicates a moment corresponding to a boundary of a system frame number (SFN) at which an end boundary of a system information (SI) window for sending the SIB is located, or indicates a moment corresponding to a boundary of an SFN immediately after an end boundary of an SI window for sending the SIB. The UE processes the time information to obtain a time reference.

Abstract: Embodiments of this application provide a secure communication method. In the method, security check is introduced in a plaintext information transmission process. An access network device preconfigures a security check value or a correspondence between a security check value and plaintext information, and performs security check in subsequent communication.

Abstract: This application discloses a communication method. The communication method includes: First UE receives a first message from a first access network device, where the first message is used by the first UE to perform RRC reconfiguration, the first message includes a network coding NC configuration parameter, the NC configuration parameter includes first indication information, and the first indication information indicates the terminal first UE to perform an NC operation with a second access network device; and the first UE separately performs NC operations on a first coded packet and a second coded packet based on the first message, where the first coded packet is a coded packet generated or received by the first access network device, and the second coded packet is a coded packet generated or received by the second access network device.

Abstract: Embodiments of this application provide a communication method and apparatus. The method includes: A DU receives uplink data from a terminal device; the DU allocates a first cell radio network temporary identifier C-RNTI and a first DU interface identifier to the terminal device; the DU sends a first message to a central unit CU, where the first message includes the first C-RNTI and the first DU interface identifier; and the DU receives a second message from the CU, where the second message includes the first C-RNTI or the first DU interface identifier. The communication method and apparatus provided in embodiments of this application can reduce processing load of the DU and improve communication efficiency.

Abstract: This application provides a data transmission method and a communication apparatus. The data transmission method includes: A terminal device receives first information from a first access network device, where the first information indicates the terminal device to be handed over and connected to a second access network device. The terminal device sends a first data packet to the second access network device after the terminal device successfully accesses the second access network device, where the first data packet is a data packet that has been sent by the terminal device to the first access network device before the terminal device successfully accesses the second access network device.

Abstract: A data transmission method and corresponding apparatus are provided. The method implemented by a terminal device includes: receiving indication information from a network device, where the indication information includes a bit sequence, a value of an ith bit in the bit sequence indicates a usage status of an ith logical channel in M logical channels associated with a radio bearer, and a duplication transmission function is configured for the radio bearer; transmitting data based on the indication information through at least one logical channel associated with the radio bearer. According to the application, the M logical channels are sorted based on IDs of cell groups associated with the M logical channels and IDs of the M logical channels, and the ith bit indicates the usage status of the ith logical channel, thereby enabling the terminal transmitting data via at least one logical channel associated with the radio bearer.

Abstract: This application provides a communication method and a communications apparatus, to provide a solution for processing a conflict between uplink resources. The method includes: a terminal device obtains a first uplink resource, where the first uplink resource is used to send a first service. The terminal device obtains a second uplink resource, where the second uplink resource is used to send a second service, and the first uplink resource and the second uplink resource completely or partially overlap in a time domain. The terminal device determines a target uplink resource to be used in the time domain, where the target uplink resource is the first uplink resource or the second uplink resource. The terminal device sends data on the target uplink resource in the time domain.