CN115396927A

CN115396927A - Communication method and device

Info

Publication number: CN115396927A
Application number: CN202210810156.0A
Authority: CN
Inventors: 耿婷婷; 严乐; 张宏平; 曾清海
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2018-12-29
Filing date: 2018-12-29
Publication date: 2022-11-25
Also published as: WO2020135850A1; CN111385830B; CN111385830A

Abstract

According to the communication method, the communication device and the communication system, the first access network equipment sends the first message comprising the identification information of the terminal equipment, the reason for the terminal equipment to initiate the establishment of the Radio Resource Control (RRC) connection and the identification information of the Public Land Mobile Network (PLMN) selected by the terminal equipment to the second access network equipment, and the first access network equipment receives the response message of the first message from the second access network equipment, so that the terminal equipment can be selected to be suitable service access network equipment as soon as possible, and the time delay of the terminal equipment for accessing the network is reduced.

Description

Communication method and device

Technical Field

The present application relates to the field of communications technologies, and in particular, to a communication method and apparatus capable of implementing fast handover.

Background

In a wireless communication system, for example, 5G (also referred to as new radio), when a serving base station cannot provide a service or a network service required by a terminal device, a Radio Resource Control (RRC) release message without security protection may be sent, and the RRC release message may be carried on a Signaling Radio Bearer (SRB) 0, for example. After receiving the RRC release message, the terminal device releases the RRC connection with the serving base station, and the terminal device may select to continue to camp on the cell under the serving base station or reselect to another new cell.

However, whether the terminal device selects a cell residing under the serving base station, or the terminal device reselects to another new cell and initiates an access procedure again in the new cell, the network access delay of the terminal device is increased.

Disclosure of Invention

The communication method provided by the embodiment of the application can reduce the time delay of the terminal equipment accessing the network.

In order to achieve the above purpose, the embodiment of the present application adopts the following technical solutions:

in a first aspect, a communication method is provided, including: a first access network device sends a first message to a second access network device, wherein the first message comprises identification information of a terminal device, a reason for the terminal device to initiate Radio Resource Control (RRC) connection establishment and identification information of a Public Land Mobile Network (PLMN) selected by the terminal device; the first access network device receives a response message (first response message) to the first message from the second access network device.

The communication method can be used for sending the first message to the second access network equipment through the first access network equipment under the condition that the first access network equipment cannot provide the service required by the UE, so that the proper service access network equipment can be selected for the UE as soon as possible, and the time delay of the terminal equipment accessing the network is reduced.

In a possible implementation manner of the first aspect, the first access network device may determine the target access network device (the second access network device) according to the measurement report and the service information sent by the terminal device. Optionally, the measurement report may be a measurement report, and the service information may include registered target core network node identification information and/or a list of single network slice selection support information. Therefore, the target access network equipment can be determined under the condition that the first access network equipment cannot support the requirement of the terminal equipment, and the time delay of the terminal equipment accessing the network is shortened.

In a possible implementation manner of the first aspect, the response message of the first message sent by the second access network device to the first access network device may include a content of the security mode command message and a content of the RRC reconfiguration message, so that the second access network device may, under the condition that the terminal device is allowed to access, transfer the content of the security mode command message and the content of the RRC reconfiguration message through the first access network device before the terminal device directly sends an access request to the second access network device, and shorten a time delay of accessing the terminal device to the network.

In a possible implementation manner of the first aspect, the content of the RRC reconfiguration message is security protection performed according to an initial key and a security algorithm, where the security protection includes integrity protection or includes integrity protection and ciphering protection. By the implementation mode, the influence on the terminal equipment is reduced, and the content of the RRC reconfiguration message is subjected to security protection, so that the authenticity and the privacy of the message can be ensured.

In a possible implementation manner of the first aspect, the content of the RRC reconfiguration message is security protection performed according to a first key and a security algorithm, where the first key is determined according to an initial key from a core network and information of a source cell, and the source cell belongs to the first access network device. Optionally, in this implementation, the response message of the first message received by the first access network device may further include information of the first key. By the implementation mode, the content of the RRC reconfiguration message is subjected to security protection, so that the authenticity and the privacy of the message can be ensured.

In the above first key information, the information of the first key includes first key indication information or a first key, so that the first access network device can transmit the information of the first key to the terminal device, so that the terminal device can use a correct key for security protection.

In a possible implementation manner of the first aspect, in a case that the terminal device sends a response message of the security mode command message to the first access network device, the first access network device receives a response message (a second response message) of the security mode command message from the terminal device, so that the first access network device knows that the terminal device activates the security mode or that the security mode activation fails.

In a possible implementation manner of the first aspect, in a case that the second access network device configures the terminal device to send the second response message to the second access network device, the first access network device receives second indication information from the second access network device, where the second indication information indicates that the first access network device does not receive the response message of the security mode command message, so that when the terminal device sends the second response to the second access network device, energy consumption caused by the fact that the first access network device receives a corresponding message of the security mode command message due to inconsistency in operations of the terminal device and the first access network device is avoided.

In a possible implementation manner of the first aspect, the measurement report is a measurement report in advance, and optionally, the measurement report in advance may be carried in a message (message) 3 or a message5, for example.

In a possible implementation manner of the first aspect, in a case that the advance measurement report is received through signaling or a message before message4, the advance measurement report to be sent by the terminal device may be determined based on information of a random access preamble sent by the terminal device, and uplink grant resource information for transmitting the advance measurement report may be sent to the terminal device through message 2. By the implementation mode, the terminal equipment can report the measurement report quickly, so that the service base station can execute mobility-related configuration quickly, and the data transmission experience of the terminal equipment is improved. It should be noted that this implementation may be implemented independently of other implementations of the first aspect.

In a second aspect, a communication method is provided, including: the second access network equipment receives a first message from the first access network equipment, and sends a response message (first response message) of the first message to the first access network equipment, wherein the first message comprises identification information of the terminal equipment, a reason for the terminal equipment to initiate Radio Resource Control (RRC) connection establishment, and identification information of a Public Land Mobile Network (PLMN) selected by the terminal equipment.

In a possible implementation manner of the second aspect, the first response message may include content of the security mode command message and content of the RRC reconfiguration message, so that the second access network device may, under the condition that the terminal device is allowed to access, transfer the content of the security mode command message and the content of the RRC reconfiguration message in advance, and shorten a time delay of accessing the network by the terminal device.

In a possible implementation manner of the second aspect, the content of the RRC reconfiguration message is security protection performed according to an initial key and a security algorithm, where the security protection includes integrity protection or includes integrity protection and ciphering protection. By the implementation mode, the influence on the terminal equipment is reduced, and the content of the RRC reconfiguration message is subjected to security protection, so that the authenticity and the privacy of the message can be ensured.

In a possible implementation manner of the second aspect, the content of the RRC reconfiguration message is security protection performed according to a first key and a security algorithm, where the first key is determined according to an initial key from a core network and information of a source cell, and the source cell belongs to the first access network device. Optionally, in this implementation, the response message of the first message received by the first access network device may further include information of the first key. Through the implementation mode, the content of the RRC reconfiguration message is subjected to security protection, so that the authenticity and the privacy of the message can be ensured

In a possible implementation manner of the second aspect, the information of the first key includes first key indication information or a first key, so that the first access network device can transmit the information of the first key to the terminal device, so that the terminal device can use a correct key for security protection.

In a possible implementation manner of the second aspect, in a case that the second access network device configures the terminal device to send the second response message to the second access network device, the second access network device sends second indication information to the first access network device, where the second indication information indicates that the first access network device does not receive the second response message, so that when the terminal device sends the second response to the second access network device, energy consumption caused by receiving, by the first access network device, a corresponding message of the security mode command message due to inconsistency between operations of the terminal device and the first access network device is avoided.

In a possible implementation manner of the second aspect, the second access network device receives the second response message from the terminal device, so that the second access network device learns that the terminal device activates the security mode or that the security mode activation fails.

In a possible implementation manner of the second aspect, the second access network device receives, from the terminal device, a third response message, for example, an RRC reconfiguration complete message or a handover complete message, which indicates that the RRC reconfiguration is complete, and may switch to the second access network device.

Optionally, assuming that the content of the RRC reconfiguration message is security-protected according to the initial key, the third response message may be security-protected according to the initial key, or may also be security-protected according to a second key, where the second key is determined (derived) according to the initial key and information of the target cell; assuming that the content of the RRC reconfiguration message is security protected according to the first key, the third response message may be security protected according to the third key, which is determined (derived) according to the first key and the information of the target cell, or may be security protected according to the second key. Optionally, the information of the target cell may include at least one of a Physical Cell Identity (PCI) of the target cell and frequency point information of the target cell, for example.

In a third aspect, a communication method is provided, including: the communication device receives a security mode command message from a first access network device, wherein the content of the security mode command message is consistent with the content of a security mode message determined by a second access network device, the security mode command message comprises information of a first key, and the first key is determined according to an initial key determined by a core network and information of a source cell, wherein the source cell belongs to the first access network device; and sending a response message of the security mode command message, wherein the response message of the security mode command is security-protected according to the first secret key.

In a possible implementation manner of the third aspect, the information of the first key includes first key indication information or a first key, where the first key indication information is used to indicate that the first key is determined according to the initial key and information of the source cell.

In a possible implementation manner of the third aspect, the communication device sends, to the second access network device, a second message indicating that RRC reconfiguration is completed, where the second message is used for security protection according to a second key, the second key is determined according to the first key, an identifier of a target cell, and a target cell frequency point, and the target cell belongs to the second access network device.

In a possible implementation manner of the third aspect, the communication device receives first indication information from the first access network device, where the first indication information is used to indicate a response message (second response message) for sending the security mode command message to the second access network device.

In a possible implementation manner of the third aspect, the communication device may be a response message that sends the security mode command message to the first access network device.

In a possible implementation manner of the third aspect, the communication device sends an advance measurement report to the first access network device, where the advance measurement report may be carried in a radio resource control, RRC, establishment request (message 3) or an RRC establishment complete message (message 5) in a random access procedure, for example.

In a possible implementation manner of the third aspect, in a case that the advanced measurement report is sent through signaling or a message before message4, the communication apparatus indicates that there is the advanced measurement report to be sent to the first access network device through a random access preamble (message 1); and receiving a random access response (message 2) from the first access network device, thereby obtaining uplink authorized resource information for sending the advanced measurement report. It should be noted that this implementation may be implemented independently of other implementations of the third aspect.

In a possible implementation manner of the third aspect, the communication device indicates, to the first access network device, that the advance measurement report is not completely sent, so that the first access network device may know whether sending of the advance measurement report is completed, so as to perform corresponding processing.

In a fourth aspect, a communication method is provided, including: the first node sends a message for transmitting a non-access stratum signaling of the terminal equipment to the core network node, receives a response message from the core network node, and sends a message comprising an initial context establishment response, a session resource identifier and address information for transmitting downlink data of the session resource to the core network node after the RRC reconfiguration of the terminal equipment is completed.

By the communication method, the multi-connection configuration is configured for the terminal equipment in advance in the process of establishing the initial connection for the terminal equipment by the first node and the core network node, so that the signaling overhead between the first node and the core network node is reduced.

In a fifth aspect, a communication method is provided, including: the method comprises the steps of receiving a message for transferring non-access stratum signaling of a terminal device to a core network node from a first node, sending a response message to the first node, and receiving a message comprising an initial context establishment response, a session resource identification and address information for transmitting downlink data of the session resource from the first node after RRC reconfiguration of the terminal device is completed.

In a sixth aspect, a communication device is provided for implementing the method of the first aspect. The communication device may be the first access network device in the first aspect, or a device including the first access network device, or a component (chip or circuit) configured in the first access network device.

In a seventh aspect, a communication device is provided for implementing the method of the second aspect. The communication device may be the second access network device in the second aspect, or a device including the second access network device, or a component (chip or circuit) configured in the second access network device.

In an eighth aspect, a communication device is provided for implementing the method of the third aspect. The communication device may be a terminal device, or a device including the terminal device, or a component (chip or circuit) configured in the second access network device.

In a ninth aspect, a communication device is provided for implementing the method of the fourth aspect. The communication device may be a first node (access network equipment), or a device including the first node, or a component (chip or circuit) configured in the first node.

In a tenth aspect, a communication device is provided for implementing the method of the fifth aspect. The communication device may be a core network node or a device including the core network node, or a component (chip or circuit) configured at the core network node.

The communication device of any one of the sixth to tenth aspects includes modules, units, or means (means) for implementing the method, and the modules, units, or means may be implemented by hardware, software, or hardware executing corresponding software. The hardware or software includes one or more modules or units corresponding to the above functions.

In an eleventh aspect, there is provided a communication apparatus comprising: a processor and a memory; the memory is configured to store computer instructions that, when executed by the processor, cause the communication device to perform the method of any of the above aspects.

In a twelfth aspect, a communication apparatus is provided, including: a processor; the processor is configured to be coupled to the memory, and after reading the instructions in the memory, perform the method according to any of the above aspects according to the instructions. In a sixth aspect, there is provided a computer readable storage medium having stored therein instructions which, when run on a computer, cause the computer to perform the method of any of the above aspects.

In a thirteenth aspect, there is provided a computer program product containing instructions which, when executed, enable a communication device to perform the method of any of the above aspects.

In a fourteenth aspect, there is provided a communication device (which may be a chip or a system of chips, for example) comprising a processor configured to implement the method referred to in any of the above aspects. In one possible design, the communication device further includes a memory for storing necessary program instructions and data. When the communication device is a chip system, the communication device may be constituted by a chip, or may include a chip and other discrete devices.

A fifteenth aspect provides a communication system comprising the communication apparatus of the sixth aspect and the communication apparatus of the seventh aspect, or comprising the communication apparatuses of the sixth-eighth aspects, or comprising the communication apparatuses of the ninth and tenth aspects.

Drawings

Fig. 1 is a schematic structural diagram of a communication system according to an embodiment of the present application;

fig. 2 is a schematic structural diagram of an access network device and a terminal device according to an embodiment of the present application;

fig. 3 is a flowchart illustrating a communication method according to an embodiment of the present application;

fig. 4 is a flowchart illustrating another communication method according to an embodiment of the present application;

fig. 5 is a flowchart illustrating a further communication method according to an embodiment of the present application;

fig. 6 is a flowchart illustrating a further communication method according to an embodiment of the present application;

fig. 7 is a flowchart illustrating a further communication method according to an embodiment of the present application;

fig. 8 is a flowchart illustrating a further communication method according to an embodiment of the present application;

fig. 9 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 11 is a schematic structural diagram of a communication device according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Where in the description of the present application, "/" indicates a relationship where the objects associated before and after are an "or", unless otherwise stated, for example, a/B may indicate a or B; in the present application, "and/or" is only an association relationship describing an associated object, and means that there may be three relationships, for example, a and/or B, and may mean: a exists alone, A and B exist simultaneously, and B exists alone, wherein A and B can be singular or plural. Also, in the description of the present application, "a plurality" means two or more than two unless otherwise specified. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of the singular or plural items. For example, at least one (one) of a, b, or c, may represent: a, b, c, a-b, a-c, b-c, or a-b-c, wherein a, b, c may be single or multiple. In addition, in order to facilitate clear description of technical solutions of the embodiments of the present application, in the embodiments of the present application, terms such as "first" and "second" are used to distinguish the same items or similar items having substantially the same functions and actions. Those skilled in the art will appreciate that the terms "first," "second," etc. do not denote any order or quantity, nor do the terms "first," "second," etc. denote any order or importance.

In addition, the network architecture and the service scenario described in the embodiment of the present application are for more clearly illustrating the technical solution of the embodiment of the present application, and do not constitute a limitation to the technical solution provided in the embodiment of the present application, and it can be known by a person skilled in the art that the technical solution provided in the embodiment of the present application is also applicable to similar technical problems along with the evolution of the network architecture and the appearance of a new service scenario.

As shown in fig. 1, a communication system 10 is provided in accordance with an embodiment of the present application. The communication system 10 includes

access network devices

20 and 40, and one or more terminal devices 30 connected to the

access network devices

20 and 40. The access network device 20 shown in fig. 1 interacts with the access network device 40 and with any of the terminal devices 30, for example. In this embodiment, access network device 20 sends a first message to access network device 40, where the first message includes identification information of terminal device 30, a reason for RRC establishment initiated by terminal device 30, and identification information of a public land mobile network selected by terminal device 30, and access network device 40 sends a corresponding response message to access network device 20 after receiving the first message. The first message may be, for example, an access request message for initiating an access request to access network device 40, so that access network device 40 can determine whether to admit terminal device 30.

In a possible manner, in the case where access network device 40 determines to accommodate terminal device 30, an acknowledgement message (one type of response message) may be sent to access network device 20. Optionally, the acknowledgement message may carry the content of the security mode command message and the content of the RRC reconfiguration message. Further, the access network device 20 may forward the content of the security mode command message and the content of the RRC reconfiguration message to the terminal device 30, and after receiving the content of the Security Mode Command (SMC) message and the content of the RRC reconfiguration message, the terminal device 30 may perform corresponding operations, for example, send a security mode command complete message to the

access network device

20 or 40 and send an RRC reconfiguration complete message to the access network device 40, which is not limited in this embodiment of the present application. It should be noted that, in the embodiment of the present application, accepting a terminal device is a brief expression manner for allowing the terminal device to access.

In yet another possible manner, in the case where access network device 40 determines not to accommodate terminal device 30, negative acknowledgement information may be sent to access network device 20, so that access network device 20 knows that access network device 40 does not accommodate terminal device 30.

It is understood that one access network device 40 is illustrated here as an example. Alternatively, access network device 20 may interact similarly with multiple access network devices 40, and the response messages sent by different access network devices 40 to access network device 20 may differ.

Here, the RRC establishment cause may include, for example, at least one of: emergency calls, high Priority access, passive services, actively triggered signaling services, actively triggered data services, actively triggered voice calls, actively triggered video calls, actively triggered Short Message Services (SMS), high Priority access for Multimedia Priority Services (MPS), high Priority access for critical services (MCS), and other RRC establishment causes. It is understood that the RRC establishment cause may also be referred to as an RRC connection establishment cause.

Optionally, the terminal device may also have a communication connection with multiple access network devices and may send and receive data at the same time, which may be referred to as a multi-connectivity (MC), where one of the multiple access devices may be responsible for interacting with the terminal device for radio resource control messages and interacting with a core network control plane entity, and then the access device may be referred to as an MN, and the remaining access devices may be referred to as an SN.

Optionally, as shown in fig. 2, a schematic diagram of a hardware structure of the access network device 20 and the terminal device 30 provided in the embodiment of the present application is shown.

The terminal device 30 includes at least one processor (illustrated in fig. 2 by including one processor 301) and at least one transceiver (illustrated in fig. 2 by including one transceiver 303). Optionally, the terminal device 30 may further include at least one memory (exemplarily illustrated in fig. 2 by including one memory 302), at least one output device (exemplarily illustrated in fig. 2 by including one output device 304) and at least one input device (exemplarily illustrated in fig. 2 by including one input device 305).

The processor 301, the memory 302 and the transceiver 303 are connected by a communication line. The communication link may include any path that conveys information between the aforementioned components.

The processor 301 may be a general-purpose Central Processing Unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of programs in accordance with the present disclosure. In a specific implementation, the processor 301 may also include a plurality of CPUs, and the processor 301 may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor, as an example. A processor herein may refer to one or more devices, circuits, or processing cores that process data (e.g., computer program instructions).

The memory 302 may be a device having a storage function. Such as, but not limited to, read-only memory (ROM) or other types of static memory devices that can store static information and instructions, random Access Memory (RAM) or other types of dynamic memory devices that can store information and instructions, electrically erasable programmable read-only memory (EEPROM), compact disk read-only memory (CD-ROM) or other optical disk storage, optical disk storage (including compact disk, laser disk, optical disk, digital versatile disk, blu-ray disk, etc.), magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. The memory 302 may be separate and coupled to the processor 301 via a communication link. The memory 302 may also be integrated with the processor 301.

The memory 302 is used for storing computer-executable instructions for executing the present application, and is controlled by the processor 301. Specifically, the processor 301 is configured to execute computer-executable instructions stored in the memory 302, so as to implement the communication method described in the embodiment of the present application. Optionally, the computer execution instruction in the embodiment of the present application may also be referred to as an application program code or a computer program code, which is not specifically limited in this embodiment of the present application.

The transceiver 303 may use any transceiver or the like for communicating with other devices or communication networks, such as ethernet, radio Access Network (RAN), wireless Local Area Network (WLAN), or the like. The transceiver 303 includes a transmitter Tx and a receiver Rx. The transceiver 303 may also be an interface circuit.

The output device 304 is in communication with the processor 301 and may display information in a variety of ways. For example, the output device 304 may be a Liquid Crystal Display (LCD), a Light Emitting Diode (LED) display device, a Cathode Ray Tube (CRT) display device, a projector (projector), or the like.

The input device 305 is in communication with the processor 301 and may accept input from a user in a variety of ways. For example, the input device 305 may be a mouse, a keyboard, a touch screen device, or a sensing device, among others.

The access network device 20 includes at least one processor (illustrated in fig. 2 as including one processor 201), at least one transceiver (illustrated in fig. 2 as including one transceiver 203), and at least one network interface (illustrated in fig. 2 as including one network interface 204). Optionally, the access network device 20 may further include at least one memory (the example in fig. 2 is illustrated as including one memory 202). The processor 201, the memory 202, the transceiver 203, and the network interface 204 are connected via a communication line. The network interface 204 is configured to connect with a core network device through a link (e.g., S1 interface), or connect with a network interface of another access network device through a wired or wireless link (e.g., X2 interface) (not shown in fig. 2), which is not specifically limited in this embodiment of the present application.

Optionally, the access network device 20 in this embodiment is a device that accesses the terminal device 30 to a wireless network, and may be an evolved Node B (eNB or eNodeB) in Long Term Evolution (LTE); or a base station in eLTE; or a base station in a fifth generation (5 g) network or a Public Land Mobile Network (PLMN) for future evolution, a broadband network service gateway (BNG), a convergence switch or a non-third generation partnership project (3 rd generation partnership project,3 gpp) access device, etc., which is not specifically limited in this embodiment of the present application. Optionally, the base station in the embodiment of the present application may include various forms of base stations, for example: a macro base station, a micro base station (also referred to as a small station), a relay station, an access point, and the like, which are not specifically limited in this embodiment of the present application.

In one network configuration, the access network may comprise Centralized Unit (CU) nodes, or Distributed Unit (DU) nodes, or RAN equipment comprising CU nodes and DU nodes, or control plane CU nodes (CU-CP nodes) and user plane CU nodes (CU-UP nodes) and DU nodes.

The communication between the access network device and the terminal device follows a certain protocol layer structure. For example, the control plane protocol layer structure may include functions of protocol layers such as a Radio Resource Control (RRC) layer, a Packet Data Convergence Protocol (PDCP) layer, a Radio Link Control (RLC) layer, a Medium Access Control (MAC) layer, and a physical layer. The user plane protocol layer structure can comprise functions of protocol layers such as a PDCP layer, an RLC layer, an MAC layer, a physical layer and the like; in one implementation, a Service Data Adaptation Protocol (SDAP) layer may be further included above the PDCP layer.

The functions of these protocol layers may be implemented by one node, or may be implemented by a plurality of nodes; for example, in an evolved structure, a RAN device may include a Centralized Unit (CU) and a Distributed Unit (DU), and a plurality of DUs may be centrally controlled by one CU.

The CU and the DU may be divided according to protocol layers of the radio network, for example, functions of a PDCP layer and above protocol layers are provided in the CU, and functions of protocol layers below the PDCP layer, for example, functions of an RLC layer and a MAC layer, are provided in the DU. Alternatively, the CU has functions above the PDCP layer (including PDCP, RRC, and SDAP), and the DU has functions below the PDCP layer (including RLC, MAC, and PHY).

This division of the protocol layers is only an example, and it is also possible to divide the protocol layers at other protocol layers, for example, at the RLC layer, and set the functions of the RLC layer and the protocol layers above to CU, and the functions of the protocol layers below the RLC layer to DU; alternatively, the functions may be divided into some protocol layers, for example, a partial function of the RLC layer and a function of a protocol layer above the RLC layer may be provided in the CU, and the remaining function of the RLC layer and a function of a protocol layer below the RLC layer may be provided in the DU. In addition, the processing time may be divided in other manners, for example, by time delay, a function that needs to satisfy the time delay requirement for processing is provided in the DU, and a function that does not need to satisfy the time delay requirement is provided in the CU.

Optionally, the terminal device 30 in this embodiment may be a device for implementing a wireless communication function, for example, a terminal or a chip that can be used in the terminal. The terminal may be a User Equipment (UE), an access terminal, a terminal unit, a terminal station, a mobile station, a distant station, a remote terminal, a mobile device, a wireless communication device, a terminal agent or a terminal device, etc. in a 5G network or a PLMN which is evolved in the future. The access terminal may be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device or a wearable device, a Virtual Reality (VR) terminal device, an Augmented Reality (AR) terminal device, a wireless terminal in industrial control (industrial control), a wireless terminal in self driving (self), a wireless terminal in remote medical (remote medical), a wireless terminal in smart grid (smart grid), a wireless terminal in transport security (transport security), a wireless terminal in city (smart), a wireless terminal in smart home (smart), etc. The terminal may be mobile or stationary.

Optionally, in this embodiment of the application, the access network device 20 and the terminal device 30 shown in fig. 1 or fig. 2 may also be referred to as a communication apparatus, which may be a general device or a special device, and this is not specifically limited in this embodiment of the application.

In various embodiments of the present application, a beam (beam) may be understood as a spatial resource, and may refer to a transmission or reception precoding vector having energy transmission directivity. Moreover, the sending or receiving precoding vector can be identified by index information, where the index information may correspond to a resource Identifier (ID) of the configured terminal, for example, the index information may correspond to an identifier or a resource of the configured SSB; the identifier or resource of the configured CSI-RS can be corresponded; or may be an identifier or resource of a correspondingly configured uplink Sounding Reference Signal (SRS). Optionally, the index information may also be index information explicitly or implicitly carried by a signal or channel carried by a beam. The energy transmission directivity may refer to precoding a signal to be transmitted by using the precoding vector, the signal subjected to precoding has a certain spatial directivity, and the received signal subjected to precoding by using the precoding vector has a good receiving power, such as meeting a receiving demodulation signal-to-noise ratio; the energy transmission directivity may also mean that the same signal transmitted from different spatial locations received through the precoding vector has different reception powers. Alternatively, the same communication device (such as a terminal device or a network device) may have different precoding vectors, and different devices may also have different precoding vectors, that is, corresponding to different beams. One communication device may use one or more of a plurality of different precoding vectors at the same time, i.e. may form one beam or a plurality of beams at the same time, depending on the configuration or capabilities of the communication device.

In the embodiments of the present application, as an implementation manner, the message 1-message 4 may correspond to a first message-a fourth message in a contention random access procedure, where the message may also be abbreviated as MSG. It is understood that message 1 may also be referred to as message 1, message 2 may also be referred to as message 2, and so on. As another implementation manner, the competitive random access may also be implemented through a two-step process, where messages included in the competitive random access flow of the two-step process may be referred to as message a (first message) and message b (second message), where the function implemented by message a is the same as that implemented by message 1 plus message3 described above, and the function implemented by message b is the same as that implemented by message 2 and message4 described above. Therefore, when referring to message3 in the following of the embodiments of the present application, it may refer to another message having the function of message3, such as message a, and when referring to message4 in the following of the embodiments of the present application, it may refer to another message having the function of message4, such as message b. In the embodiment of the present application, the first message transmitted by the terminal device after the message having the function of message4 is collectively referred to as message 5. The function of each message in the contention random access process is not described in detail in the embodiments of the present application.

The following will explain the communication method provided by the embodiment of the present application with reference to fig. 1 and fig. 2.

It should be noted that, in the following embodiments of the present application, names of messages between network elements or names of parameters in messages are only an example, and other names may also be used in a specific implementation, which is not specifically limited in this embodiment of the present application.

As shown in fig. 3, a communication method provided for the embodiment of the present application includes the following steps:

s301, the terminal device sends a measurement report to the first access network device.

Here, the terminal device may perform signal quality measurement, obtain a signal quality measurement result, and generate a measurement report according to the signal quality measurement result.

It is understood that the terminal device herein may be a terminal device in an idle (idle) or deactivated (Inactive) state. The deactivated (inactive) state is an RRC state, and may also be referred to as "RRC deactivated dynamic" or "deactivated dynamic". Similar to the idle state, in the deactivated state, the terminal device disconnects RRC connection from the network. But unlike the idle state, in the deactivated state, the terminal device and the access network device preserve the context of the terminal. The access network device that configures the terminal device to enter the deactivated state and stores the context information of the terminal device is generally referred to as a source network device or an anchor (anchor) network device. Optionally, the definition of the deactivated state may refer to the related description in 3gpp ts38.300.

The measurement report may include identification information of at least one cell, or include identification information of at least one cell and a corresponding signal quality measurement result. Optionally, the method may further include identification information of at least one beam in the at least one cell, or may further include identification information of at least one beam in the at least one cell and a corresponding beam measurement result. The at least one cell may include a cell where the terminal device is currently located and other cells, where the other cells may include other cells belonging to the first network device and/or other cells not belonging to the first network device. The number of other cells may be an integer greater than or equal to 0, which is not limited in this embodiment of the present application. Optionally, the identification information of at least one cell carried in the measurement report may be identification information of a cell whose signal quality meets a first preset condition, and the identification information of at least one beam may be identification information of a beam whose signal quality meets a second preset condition, or identification information of all beams belonging to the cell. The first preset condition and the second preset condition may be configured by the access network device, or may be predefined, which is not limited in this embodiment of the present application. The measurement report in the embodiments of the present application may also be referred to as a signal quality measurement report or a signal quality measurement result, or other names.

Optionally, for the terminal device in the idle state, the measurement report may be sent to the first access network device through an RRC setup request message (e.g., message 3) or an RRC setup complete message (e.g., message 5) in the random access process. The first access network device is the access network device where the terminal device is currently located. In one possible approach, the first access network device may also be referred to as a source base station.

Optionally, for the terminal device in the inactive state, the measurement report may be sent to the first access network device through message3 (or message a). The first access network device may be an anchor network device or a non-anchor network device.

In the embodiment of the present application, the measurement report sent by the message3 (or the message a) or the message5 may be referred to as an Early Measurement Report (EMR). Of course, the EMR may also be sent by other messages or signaling, for example, before the access network device sends the collision resolution message (message 4 (or message b)), the measurement report and the message3 (or message a) are multiplexed in the same MAC packet, for example, multiplexed in a MAC Service Data Unit (SDU), or the measurement report and the message3 (or message a) are respectively sent on different uplink grant resources before the message4 (or message b).

Optionally, the message3 may include, for example, identification information of the terminal device and an RRC establishment cause (RRC establishment cause), where the identification information of the terminal device may be, for example, initial UE-Identity (initial UE-Identity). The initial ue identity information may be, for example, information related to S-temporary mobile subscriber identity (S-TMSI). In the case where the measurement report is transmitted by the message3, the measurement report may be included in the message 3.

Optionally, the message5 may include identification information of a selected Public Land Mobile Network (PLMN). Further, the message5 may include, in addition to the selected PLMN identification information, registered target core network node identification information and a single network slice selection support information (S-NSSAI) list and other information, which is not limited in this embodiment of the present application. In the case where the measurement report is transmitted by the message5, the measurement report may be included in the message 5.

It may be understood that the terminal device may also send the measurement report to the first access network device at other occasions, as long as the first access network device can determine a suitable target access network device (second access network device) in advance, which is not limited in this embodiment of the present invention.

S302, the terminal device sends service information to the first access network device.

The service information here refers to information indicating a service or a network requirement of the terminal device, and optionally, the service information may also be referred to as network information.

In a possible manner, the service information may include registered target core network node identification information and/or an S-NSSAI list.

For example, in the 5G system, the core network node may be an access mobility management function (AMF). In the LTE system, the core network node may be, for example, a Mobility Management Entity (MME).

It should be understood that the service information may be sent through the message5, or may be sent in other manners, which is not limited in this embodiment of the application.

It should be noted that S301 and S302 may be executed simultaneously. For example, the measurement report and the service information may be sent to the first access network device via a message (e.g., message 5).

In addition, S301 and S302 may also be executed at different times, that is, the measurement report and the service information may be sent to the first access network device through different messages, and the sequence of S301 and S302 is not limited in this embodiment of the application.

According to the measurement report and the service information, the first access network device may determine the second access network device.

For example, the first access network device determines whether the terminal device can be supported or meet the requirement of the terminal device according to the service information, so as to determine whether to provide the service for the terminal device. If the first access network device determines that the terminal device cannot be provided with the service, the second access network device may be further determined according to the measurement report, and S304 and subsequent processes are executed. It can be understood that, if the first access network device determines that the service can be provided for the terminal device, a suitable core network node may be selected for the terminal device according to the service information of the terminal device without performing the subsequent process of the embodiment of the present application, and the service required by the terminal device may be provided. Or, if the first access network device cannot determine the appropriate second access network device, the subsequent process of the embodiment of the present application may not be executed, and a reject message or a release message is sent to the terminal device, so as to reject providing the service required by the terminal device.

In a possible manner, for the terminal device in the deactivated state, in addition to the service information and the measurement report, the first access network device may further determine, based on configuration information of a Radio Network Area (RNA) of the terminal device, the second access network device, for example, the second access network device that meets the condition in the RNA is preferentially selected to provide a service for the terminal device.

The first access network device may not support or cannot meet the requirement of the terminal device according to the service information:

the first access network equipment determines that the target core network node is congested or the target core network node does not support the terminal equipment to access, wherein the target core network node is the target core network node identified by the registered target core network node identification information; and/or the presence of a gas in the atmosphere,

the first access network device determines that a slice is not congested or the slice does not support the terminal device access, wherein the slice is one or more slices identified by the S-NSSAI list.

Optionally, the first access network device may select a suitable second access network device according to the measurement report sent in S302, for example, select an access network device whose cell signal quality meets a preset condition as the second access network device. The preset condition here may be, for example, that the cell signal quality is greater than or equal to a preset threshold, which is not limited in this embodiment of the application. Here, the suitable second access network device is the second access network device determined by the first access network device, and it is understood that there may be more than one second access network device.

It can be understood that S301 to S302 are all optional steps, that is, the second access network device may not be determined in the above manner, but the first message may be sent to any one or more second access network devices, and this process of sending the first message to any one or more second access network devices may also be referred to as blind selection. Optionally, the first network device may determine, according to the service information in S302, that the first message needs to be sent to any one or more second access network devices, or may send the first message to any one or more second access network devices at other occasions, which is not limited in this embodiment of the present invention. And the second access network equipment is determined according to the service information and the measurement report, so that the target access network equipment can be determined by the first access network equipment under the condition that the first access network equipment cannot support the requirement of the terminal equipment, and the time delay of the terminal equipment for accessing the network is shortened.

If there are a plurality of second access network devices, the following processes are respectively executed between the first access network device and each of the second access network devices. The following is an example of a second access network device. In this embodiment, the second access network device may also be referred to as a target access network device.

S303, the first access network device sends the first message to the second access network device.

The first message at least includes identification information of the terminal device, a Radio Resource Control (RRC) establishment cause and identification information of a Public Land Mobile Network (PLMN) selected by the terminal device. The PLMN identification information selected by the terminal device is provided to the second access network device, so that the second access network device can select the core network node according to the PLMN identification information, and the identification information of the terminal device and the RRC establishment cause can be used for subsequent interaction between the second access network device and the core network node.

The identification information of the terminal device, the reason for RRC establishment, and the identification information of the public land mobile network PLMN selected by the terminal device may be obtained from information sent by the terminal device, for example, from message3 and message5 sent by the terminal device.

Optionally, the first message may further include one or more of the following information: registered core network identification information, globally Unique core network identification type (gurie-type), S-NSSAI list, dedicated NAS message. The above information may be acquired by the first access network device from a message (for example, message 5) sent by the terminal device.

In a possible manner, the first message may include part or all of the contents included in the messages 3 (or message a) and 5 sent by the terminal device to the first access network device.

Optionally, for an idle terminal device, the identifier information of the terminal device may be the identifier information of a non-access stratum, for example, a Temporary Mobile Subscriber Identity (TMSI) or a 5G-TMSI.

Optionally, for an inactive state terminal device, the identifier information of the terminal device may be an inactive radio network temporary identifier (I-RNTI).

S304, the second access network device sends a response message of the first message to the first access network device.

Accordingly, the first access network device receives a response message to the first message from the second access network device. The response message may also be referred to as a first response message.

Here, after receiving the first message, the second access network device may determine whether to allow the terminal device to access according to a network load condition or a base station function, and so on, so as to send a corresponding first response message to the first access network device. It should be noted that, in the embodiment of the present application, how the second access network device determines whether to allow the terminal device to access is not limited.

In one possible approach, in the case where the second access network device determines to admit the terminal device, an acknowledgement message (an example of the first response message) may be sent to the first access network device. Optionally, the acknowledgement message may include the content of the security mode command message and the content of the RRC reconfiguration message. It is to be understood that the contents of the security mode command message and the contents of the RRC reconfiguration message may be contained in the same acknowledgement message, or may be contained in different acknowledgement messages. Here, the RRC reconfiguration message may also be referred to as a handover message, and the name of the message is not limited in the embodiments of the present application. The content of the security mode command message is used to activate the access stratum security of the terminal device, and the content of the RRC reconfiguration message is used to switch the terminal device to the target cell, where it can be understood that the target cell is a cell to which the second access network device belongs. It is to be understood that the content of the security mode command message may also be referred to as security mode command information, and the content of the RRC reconfiguration message may also be referred to as RRC reconfiguration information. Before the terminal equipment directly sends the access request at the second access network equipment, the content of the security mode command message and the content of the RRC reconfiguration message are transmitted through the first access network equipment, and the time delay of the terminal equipment accessing the network is shortened. It is to be understood that the contents of the security mode command message and the contents of the RRC reconfiguration message may also be sent to the first access network device separately through different messages.

As an implementation manner, the content of the security mode command message and the content of the RRC reconfiguration message are included in the acknowledgement response message in the form of an encapsulated packet data convergence protocol control protocol data unit (PDCP-C PDU). Optionally, when the second access network device encapsulates the content of the security mode command message, no security protection may be performed, or only integrity protection may be performed; the second access network device may perform integrity protection, or may perform integrity protection and ciphering protection while encapsulating the content of the RRC reconfiguration message. In the embodiment of the application, the security protection includes integrity protection, or includes integrity protection and encryption protection.

In yet another possible approach, in a case where the second access network device determines not to admit the terminal device, negative acknowledgement information (another example of the first response message) may be sent to the first access network device, so that the first access network device knows that the second access network device does not admit the terminal device.

Optionally, in the embodiment of the present application, the following steps may also be included:

s305, the first access network device sends the content in the received first response message to the terminal device.

In this step, the first access network device sends the content of the security mode command message and the content of the RRC reconfiguration message to the terminal device. For example, the first access network device transparently transmits a security mode command message and an RRC reconfiguration message to the terminal device. The content of the security mode command message and the content of the RRC reconfiguration message may be sent to the terminal device through one message, or may be sent to the terminal device through different messages at different occasions. For example, the content of the security mode command message may be sent to the terminal device by a security mode command message (SMC), and the content of the RRC reconfiguration message may be sent to the terminal device by an RRC reconfiguration message. It is understood that the terminal device may send a response message to the first access network device after receiving the contents of the security mode command message transmitted by the first access network device. Or, after receiving the content of the security mode command message, the terminal device sends a response message to the first access network device or the second access network device according to the corresponding indication information. Optionally, if the first access network device receives the response message sent by the terminal device, the first access network device forwards the second response message to the second access network device. In addition, after receiving the content of the RRC reconfiguration complete message transmitted by the first access network device, the terminal device sends a response message to the second access network device. The response message mentioned in connection with this embodiment may refer to the description of the embodiment of fig. 4 in detail.

In the embodiment of the application, the first message is sent to the second access network device through the first access network device, so that a proper service access network device can be selected for the terminal device as soon as possible, and the time delay of the terminal device accessing the network is reduced.

It is to be understood that there may be different security mechanisms for the content of the RRC reconfiguration message in the response message of the first message sent by the second access network device, which will be described in detail below.

As shown in fig. 4, an embodiment of the present application further provides a communication method, which may include:

s401, the terminal device sends a measurement report to the first access network device.

S402, the terminal device sends service information to the first access network device.

S403, the first access network device sends a first message to the second access network device.

For the implementation and specific description of S401 to S403, reference may be made to the related description at S301 to S303, which is not described herein again.

S404, the second access network device sends a first response message to the first access network device.

Taking the second access network device determining to admit the terminal device as an example, the first response message includes the content of the security mode command message and the content of the RRC reconfiguration message. It is to be understood that the contents of the security mode command message and the contents of the RRC reconfiguration message may be contained in the same acknowledgement message, or may be contained in different acknowledgement messages.

In one possible approach, the content of the RRC reconfiguration message may be security protected according to an initial key and a certain security algorithm (which may be referred to as a first security algorithm). The method can reduce the influence on the terminal equipment, and moreover, the security protection is carried out on the content of the RRC reconfiguration message, so that the authenticity and the privacy of the message can be ensured.

The initial key may be from the core network device, for example, the core network device determines the initial key and sends the initial key to the second access network device.

Optionally, the first security algorithm includes an integrity protection algorithm, or the first security algorithm includes an integrity protection algorithm and an encryption algorithm. In one possible approach, the first security algorithm may be determined by the second access network device. For example, the second access network device may select an algorithm with a higher priority among security algorithms that it supports as the first security algorithm. The embodiment of the present application does not limit how to determine the first security algorithm, and the specific security algorithm.

In addition, the content of the security mode command message may include the information of the first security algorithm, so that the terminal device may know what security algorithm is used by the content of the RRC reconfiguration information. It should be noted that the information of the first security algorithm may also be sent to the first access network device through other messages or signaling, which is not limited in this embodiment of the application.

In yet another possible approach, the content of the RRC reconfiguration message may be security protected according to a first key and a first security algorithm, where the first key is determined according to the initial key and information of the source cell. Optionally, the information of the source cell may include at least one of a physical cell identifier of the source cell and a frequency point of the source cell. The source cell is a cell belonging to the first access network device and initiating an access request for the terminal device. The process of determining the first key from the initial key and the information of the source cell may also be referred to as key derivation. In this way, the content of the RRC reconfiguration message is secured so that the authenticity and privacy of the message can be guaranteed.

Optionally, in a case that the content of the RRC reconfiguration message is security protected according to the first key, the second access network device may send information of the first key to the first access network device, for example, the content of the security mode message in the first response message may include the information of the first key. By including the information of the first key in the content of the security mode message, the terminal device can know that the content of the RRC reconfiguration message is security protected according to the first key. The information of the first key may be the first key itself, or may be indication information of the first key (indicating that the first key is used). In the case that the information of the first key is indication information of the first key, the terminal device may derive the first key according to the initial key and the information of the source cell. In this embodiment, the method for sending the information of the first key to the first access network device by the second access network device is not limited.

S405, the first access network device sends the content of the security mode command message to the terminal device.

Accordingly, the terminal device receives the contents of the security mode command message.

In a possible manner, the first access network device may forward the content of the security mode command message sent by the second access network device to the terminal device through the security mode command message. Here, the content of the security mode command message sent by the first access network device to the terminal device is the same as the content of the security mode command message sent by the second access network device to the first access network device.

In one possible approach, the first access network device transparently forwards security mode command messages received from the second access network device.

S406, the terminal device sends a second response message.

The terminal device may send the second response message to the first access network device, or send the second response message to the second access network device. Optionally, the terminal device may send the second response message to the first access network device after receiving the content of the security mode command message transmitted by the first access network device. Alternatively, the terminal device may determine whether to send the second response message to the first access network device or to send the second response message to the second access network device according to the first indication information from the second access network device. The first indication information may be forwarded to the terminal device through the first access network device. For example, first indication information for instructing the terminal device to send the second response message to the second access network device may be included in the content of the security mode command message in the first response message. It is to be understood that if the first indication information is not included in the first response message, the terminal device sends the second response message to the first access network device by default. In addition, the first indication information may indicate that the second response message is sent to the first access network device, and if the first indication information is not included in the first response message, the terminal device defaults to send the second response message to the second access network device. In this embodiment of the present application, how to specifically indicate the first indication information is not limited, as long as the terminal device can determine whether to send the second response message to the first access network device or the second access network device.

It can be understood that, in the case that the second access network device instructs the terminal device to send the second response message to the second access network device, the second access network device may also send second indication information to the first access network device, where the second indication information indicates that the first access network device does not receive the second response message. Through the second indication information, when the terminal device sends the second response to the second access network device, energy consumption caused by the fact that the first access network device receives the corresponding message of the security mode command message due to the fact that the terminal device and the first access network device are inconsistent in operation can be avoided. It should be noted that the first indication information and the second indication information may be sent in the same message or in different messages, which is not limited in this embodiment of the present application.

In a possible manner, the terminal device correctly receives the content of the security mode command message, and sends a second response message to the first access network device or the second access network device according to the content of the security mode command message, so that the first access network device or the second access network device knows that the terminal device activates the security mode. The second response message may be, for example, a secure mode complete message.

In a possible manner, when the terminal device cannot activate the security mode according to the content of the security mode command message, the terminal device sends a second response message, so that the first access network device or the second access network device learns that the terminal device fails to activate the security mode. The second response message may be, for example, a security mode failure message.

Further, if the terminal device sends the second response message to the first access network device, the method shown in fig. 4 may further include: the first access network device forwards the second response message to the second access network device. For example, when the first access network device receives the second response message sent by the terminal device, the first access network device forwards the second response message to the second access network device.

It can be understood that, according to the security mechanism of the content of the RRC reconfiguration message sent by the second access network device and the sending object of the second response message (the first access network device or the second access network device), the second response message has a corresponding security mechanism:

for example, assuming that the content of the RRC reconfiguration message sent by the second access network device is security-protected according to the initial key and the first security algorithm, and the second response message is sent to the first access network device, the second response message may also be security-protected according to the initial key and the first security algorithm; or, assuming that the content of the RRC reconfiguration message sent by the second access network device is security-protected according to the initial key and the first security algorithm, and the second response message is sent to the second access network device, the second response message may be security-protected according to the same security mechanism as the third response message, which may be specifically described in the following description of the security mechanism of the third response message;

or, assuming that the content of the RRC reconfiguration message sent by the second access network device is security-protected according to the first key and the first security algorithm, and the second response message is sent to the first access network device, the second response message may also be security-protected according to the first key and the first security algorithm; or, assuming that the content of the RRC reconfiguration message sent by the second access network device is security-protected according to the first key and the first security algorithm, and the second response message is sent to the second access network device, the second response message may be security-protected according to the same security mechanism as the third response message, which may be specifically described in the following description of the security mechanism of the third response message. It can be seen that, in the case that the second response message is sent to the first access network device, the second response message may be secured according to the same security mechanism as the content of the RRC reconfiguration message described in S404, and in the case that the second response message is sent to the second access network device, the second response message may be secured according to the same security mechanism as the third response message.

On the basis of the above flow, the method shown in fig. 4 may further include the following steps:

s407, the first access network device sends the content of the RRC reconfiguration message to the terminal device.

Correspondingly, the terminal receives the content of the RRC reconfiguration message. Here, the content of the RRC reconfiguration message sent by the first access network device to the terminal device is the same as the content of the RRC reconfiguration message sent by the second access network device to the first access network device.

In a possible manner, the first access network device may transparently forward the content of the RRC reconfiguration message sent by the second access network device to the terminal device through the RRC reconfiguration message.

S408, the terminal device sends a third response message to the second access network device.

In case the RRC reconfiguration can be successfully completed, the terminal device may send a third response message (which may also be called a second message) to the second access network device. Optionally, if the RRC reconfiguration is not successfully completed, the terminal device may enter an idle state, and it can be understood that the terminal device does not need to perform S408.

In one possible approach, the third response message may be an RRC reconfiguration complete message or a handover complete message.

It is understood that the third response message may also be secured according to a certain security mechanism:

for example, assuming that the content of the RRC reconfiguration message in S404 is secured according to the initial key, the third response message may be secured according to the initial key, or may also be secured according to a second key determined (derived) according to the initial key and the information of the target cell; assuming that the content of the RRC reconfiguration message in S404 is security protected according to the first key, the third response message may be security protected according to the third key, which is determined (derived) according to the first key and the information of the target cell, or may be security protected according to the first key. Optionally, the information of the target cell may include at least one of a Physical Cell Identity (PCI) of the target cell and frequency point information of the target cell, for example. The target cell is a cell belonging to the second access network device. In a possible manner, the terminal device may obtain the information of the target cell from the content of the RRC reconfiguration message.

It should be noted that S405 and S407 may also be executed simultaneously, for example, the content of the security mode command message and the content of the RRC reconfiguration message are sent to the terminal device in one message; s407 may also be executed after S405, or S407 may also be executed before S405, which is not limited in this embodiment of the application.

In the communication method shown in the embodiment of fig. 4, through the security mechanism, the second access network device may perform security activation and reconfiguration processes on the terminal device through the first access network device, so as to switch the terminal device from the first access network device to the second access network device as soon as possible, thereby reducing the time delay of the terminal device accessing the network.

As for a manner in which a terminal device sends a measurement report in advance before message4, an embodiment of the present application provides a communication method, as shown in fig. 5, including:

s501, receiving the random access resource configuration information of the advanced measurement report from the access network equipment.

Optionally, in this embodiment of the present application, the configuration information of the random access resource may be any combination of random access preamble information, random access time domain resource information, or random access frequency domain resource information.

For example, the configuration information of the random access resource may include random access preamble information; or, the configuration information of the random access resource may include random access time domain resource information; or, the configuration information of the random access resource may include random access frequency domain resource information; or, the configuration information of the random access resource may include random access preamble information on the random access frequency domain resource, that is, the configuration information of the random access resource includes random access frequency resource information and random access preamble information; or, the configuration information of the random access resource may include random access preamble information on the random access time domain resource, that is, the configuration information of the random access resource includes the random access time domain resource information and the random access preamble information; alternatively, the configuration information of the random access resource may include a random access time domain resource and a random access preamble on the random access frequency domain resource, that is, the configuration information of the random access resource includes random access time domain resource information, random access frequency resource information and random access preamble information. Optionally, in this embodiment of the present application, the information of the random access time domain resource may include, for example, an identifier of the random access time domain resource or a configuration of the random access time domain resource, where the configuration of the random access time domain resource may include, for example, a configuration of a frame (frame), a symbol (symbol), a slot (slot), and the like.

Optionally, in this embodiment of the application, the random access frequency domain resource information may include, for example, an identifier of the random access frequency domain resource or a configuration of the random access frequency domain resource. The configuration of the random access frequency domain resource may include, for example, configuration of a bandwidth, a resource block, and the like.

Optionally, in this embodiment of the present application, the random access preamble information may include, for example, an identifier of the random access preamble or a configuration for determining the random access preamble. The configuration of the random access preamble may include, for example, a preamble.

It is to be understood that S501 is an optional step, that is, the access network device may not send the random access resource configuration information of the advanced measurement report, and the advanced measurement report may correspond to the predefined random access resource.

S502, the terminal device sends a random access preamble (preamble) to the access network device.

It is understood that the terminal device sends a preamble to the access network device, which may also be referred to as sending message 1 (message 1), and accordingly, the access network device receives the random access preamble sent by the terminal device. In the case where the terminal device has the advance measurement report to transmit, the terminal device may transmit the random access preamble according to the random access resource corresponding to the random access resource configuration information described in S501.

S503, the access network device determines whether the terminal device has a measurement report in advance to be sent according to the information of the random access preamble.

Here, the information of the random access preamble may be any one or more of: the random access preamble itself, time domain resource information used for transmitting the random access preamble, and frequency domain resource information used for transmitting the random access preamble. If the access network device learns that the information of the random access preamble code is consistent with the random access resource of the advanced measurement report configured or predefined by the access network device, the access network device determines the advanced measurement report to be sent by the terminal device, and executes S503; if the access network device learns that the information of the random access lead code does not conform to the random access resources of the advanced measurement report configured or predefined by the access network device, the access network device determines that the terminal device does not have the advanced measurement report to be sent, and processes the advanced measurement report according to a normal flow. The information of the random access preamble and the random access resource of the advance measurement report configured or predefined by the access network device may be that the information of the random access preamble is random access resource information corresponding to configuration information of a random access resource configured or predefined by the access network device.

S504, the access network equipment sends the uplink scheduling information of the advanced measurement report to the terminal equipment.

In a possible manner, the access network device may send uplink scheduling of the advanced measurement report, such as uplink grant (uplink grant) resource information, to the terminal device through a random access response (message 2). It is understood that the message 2 may include not only the uplink scheduling information of the advance measurement report, but also optionally include the uplink scheduling information of the message 3. The uplink scheduling information of the advanced measurement report and the uplink scheduling information of the message3 may be the same or different. For example, the message 2 includes 2 pieces of uplink scheduling information, grant 1, grant 2 and grant 3, grant 1 may be used to send the message3, and grant 2 may be used to send the advanced measurement report.

And S505, the terminal equipment sends a measurement report to the access network equipment in advance.

After receiving the uplink scheduling information sent by the access network device, the terminal device sends a message3 and simultaneously (may also be understood as accompanying the message 3) an advance measurement report to the access network device, or sends an advance measurement report immediately following the message3, according to the uplink scheduling information.

In a possible manner, the advance measurement report and the message3 may be sent in the same MAC packet in a multiplexing manner, such as a MAC Service Data Unit (SDU), or the measurement report and the message3 are sent on different uplink authorized resources before the message4 respectively; alternatively, the advance measurement report is included in the message 3. Optionally, if the advance measurement report to be sent is not sent completely according to the uplink scheduling information, the method may further include:

s506, indicating to the access network device that the advanced measurement report is not sent with complete information.

After the terminal device sends the advance measurement report according to the uplink scheduling information configured in S504, if the terminal device finds that the configured uplink scheduling information is not enough to completely send the advance measurement report, that is, the terminal device cannot send the advance measurement report all at once, the terminal device may indicate, to the access network device, that the advance measurement report is not sent with complete information. It will be appreciated that this information indicating that the advanced measurement report has not been sent in its entirety may be implemented in different ways: for example, the indication information indicates whether the advance measurement report is completely transmitted, and may indicate by 1 bit information (e.g., "0" indicates that the advance measurement report is completely transmitted, "1" indicates that the advance measurement report is not completely transmitted); or, the corresponding indication information may be sent only when the advance measurement report is not completely sent, and if the corresponding indication information is not completely sent, the advance measurement report is completely sent; alternatively, the corresponding indication information may be transmitted only when the transmission of the advance measurement report is complete, or if there is no corresponding indication information, the transmission of the advance measurement report is not complete.

Optionally, the indication information may be sent through a physical uplink control channel, or may be carried in an advance measurement report, which is not limited in this embodiment of the application, as long as the access network device can know whether the advance measurement report is completely sent, so as to perform corresponding processing.

It should be noted that the communication method in the embodiment shown in fig. 5 may be applied to a terminal device in an inactive state, a terminal device in an idle state, or a terminal device in which radio link re-establishment occurs, and in any scenario, the advanced measurement report may be sent according to a communication method similar to that shown in fig. 5.

It is to be understood that the communication method shown in fig. 5 may be independent of any other embodiment in the present application, and may also be combined with other embodiments in the present application. For example, the communication method shown in fig. 5 may be combined with the communication method shown in fig. 3 or fig. 4, and used for sending the advance measurement report of the communication method shown in fig. 3 or fig. 4, where the access network device shown in fig. 5 is the first access network device.

The communication method in the embodiment shown in fig. 5 enables the terminal device to report the measurement report quickly, so that the serving base station can execute mobility-related configuration faster, and improve data transmission experience of the terminal device.

An embodiment of the present application further provides a communication method, as shown in fig. 6, which may include:

s601, the first node sends a message A to the core network node.

Here, the first node may also be referred to as a first base station or a Master Node (MN). The core network node may be, for example, an AMF or an MME. The message a is a message for transmitting non-access stratum signaling of the terminal device to the core network node, and may be, for example, an initial user equipment message (initial UE message).

Optionally, before S601, the method may further include: the terminal device sends information indicating that there is a measurement report to the first node.

S602, the core network node sends a message B to the first node.

Here, the message B is used to establish a connection configuration between the first node and the core network node for the terminal device, and may be, for example, an initial context setup request (initial context setup request).

In the prior art, the first node sends a response message of the message B, for example, an initial context setup response (initial context setup response) to the core network node, in this embodiment of the present application, after S602, the response message of the message B is not sent immediately, but is sent after being merged with other message contents in the subsequent flow.

S603, the terminal device sends a measurement report to the first node.

Regarding the measurement report, reference may be made to the related description at S301, and details are not repeated here.

It is understood that, before S603, performing a security mode interaction procedure between the first node and the terminal device may further include: the first node sends a security mode command to the terminal device, and the terminal device sends a security mode completion message to the first node after activating the security mode.

It is understood that the sequence of S603 and S601, S602 is only an example, and the embodiment of the present application is not limited thereto. S603 may precede S601, or S603 may follow S601 before S602.

S604, the first node sends a request for adding the second node to provide service for the terminal equipment to the second node.

Here, the second node may also be referred to as a second base station or a Secondary Node (SN). Optionally, the request for adding the second Node to provide the service for the terminal device may be, for example, an auxiliary Node addition request (S-Node addition request). The first node sends a request to the second node, for requesting the second node to allocate resources for multi-connection operation for the terminal device. In a possible manner, the first node may determine the second node according to the measurement report and add the second node, or may determine the second node in another manner and add the second node.

S605, the second node sends a response to the first node.

Wherein the second node sends a response to the first node based on the request of the first node,

in a possible manner, the response sent by the second Node to the first Node may be, for example, an S-Node addition request response (S-Node addition request response), which is used to enable the first Node to know that the second Node can provide a service for the terminal device. The response sent by the second node to the first node may include resource configuration information for multi-connection operation allocated by the second node to the terminal device.

In a possible manner, for example, when the second Node cannot provide the required bearer or service, the response sent by the second Node to the first Node may be, for example, an auxiliary Node addition request reject (S-Node addition request reject) for making the first Node know that the second Node cannot provide the service for the terminal device. .

S606, the first node sends a message C to the terminal equipment.

The message C is used for RRC reconfiguration, and may be referred to as an RRC reconfiguration message, for example.

Optionally, the message C may include configuration information of the second node, which is used for the terminal device to establish a connection with the second node.

And after the terminal equipment receives the message C, the terminal equipment establishes connection with the second node according to the configuration information of the second node carried in the message C.

S607, the terminal equipment sends the response message of the message C to the first node.

Correspondingly, the first node receives a response message of the message C sent by the terminal device, where the response message is used to notify the first node that the terminal device completes the corresponding configuration according to the message C.

In one possible approach, the response message of the message C may be an RRC reconfiguration complete message.

S608, the first node sends a message D to the core network node.

Correspondingly, the core network node receives message D. Message D may include the initial context setup response, the session resource identifier and the corresponding address information for transmitting the downstream data of the session resource in the prior art.

In the embodiment of the application, the multi-connection configuration is configured for the terminal equipment in advance in the process of establishing the initial connection for the terminal equipment by the first node and the core network node, so that the signaling overhead between the first node and the core network node is reduced.

Another embodiment of the present application further provides a communication method, as shown in fig. 7, including:

s701, the terminal device A sends a measurement report in advance to the access network device A.

For the content of the advanced measurement report and the transmission manner, reference may be made to the related description of the foregoing embodiments.

The terminal device may be a deactivated terminal device or a terminal device in a radio link failure recovery process. Access network device a may also be referred to as a third access network device or a target access network device.

S702, the access network device A sends a message E to the access network device B to request to acquire the context of the terminal device.

After the access network device a obtains the pre-measurement report, it determines whether to request to obtain the context of the terminal device a, for example, the access device a may determine that the access network device needs to be replaced according to the cell load or other factors, and selects a suitable target access network device according to the measurement report, and if a suitable target access network device can be found, requests to obtain the context of the terminal device.

Optionally, the target access network device may be the same access network device as the access network device a, or the target access network device may be the same access network device as the access network device B, or the target access network device is an access network device different from the access network device a and the access network device B.

In the case where the target access network device is the same access network device as access network device B: when requesting to acquire the context of the terminal device, the access network device a may also send the identifier information of the target cell to the access network device B, and optionally, may also send the measurement result related to the access network device B to the access network device.

The access network device B is an access network device in which the context of the terminal device a is stored. For example: for the terminal device a in the deactivated state, the access network device B may be an access network device that configures the terminal device a to enter the deactivated state, and the access network device B may also be referred to as a source access network device or an anchor access network device; or, for the terminal device in the radio link failure recovery process, the access network device B may be an access network device where the terminal device a has a radio link failure, and the access network device B may also be referred to as a source access network device.

Alternatively, access network device B may also be referred to as a fourth access network device.

In a possible manner, the message E may be a retrieve user equipment context request (retrieve UE context request) message requesting to retrieve the context of the terminal device. Message E may also be referred to as a third message.

S703, the access network device B sends a next hop link count (NCC) to the access network device a.

Under different scenes, the NCC sent by the access network device B is different:

(1) For the deactivated scenario, the NCC sent by the access network device B to the access network device a is the same as the NCC sent by the access network device B to the terminal device when the terminal device enters the deactivated state. For example, the NCC sent by the access network device B to the access network device a may be the NCC carried in the RRC release message that the access network device B configures the terminal device to enter the deactivated state.

(2) For the scenario of radio link failure recovery, the NCC fed back to the access network device a by the access network device B may be the NCC used by the terminal device a in the access network device B or the NCC not used by the terminal device a in the access network device B (which may also be referred to as the NCC not used by the terminal device). For example, if an NCC that is not used by the terminal device a exists at the access network device B, the access network device B feeds back the NCC that is not used by the terminal device a to the access network device a, and if an NCC that is not used by the terminal device a does not exist at the access network device B, the access network device B feeds back the NCC that is used by the terminal device a at the access network device B to the access network device a. It will be appreciated that the NCC used by terminal device a at access network device B is that which access network device B is configured for. It should be noted that in this scenario, the access network device B may not send the NCC to the access network device B based on the request of the access network device a, but may send the NCC to the access network device a in advance, and at this time, S702 may not be executed. Optionally, when the access network device sends the NCC to the access network device a in advance, the execution order of S701 and S703 is not limited, for example, S703 may also be executed before S701.

In a possible manner, the access network device B may send the NCC to the access network device a in the request for obtaining the context of the terminal device, and it is understood that the name of the message for sending the NCC is not limited in this embodiment of the present application.

Optionally, the access network device B may further send the key a to the access network device a, where the key a may be based on a key used by the terminal device a when the access network device a initiates an access request or a key corresponding to the terminal device a and stored by the access network device B. The information of the cell where the terminal device a initiates the access request (the cell is a cell belonging to the access network device a) includes at least one of the following: the physical cell identity and frequency point information of the cell.

S704, the access network device a sends a handover request to the target access network device.

S705, the target access network device replies a handover response to the access network device a.

Here, the handover preparation is completed by S704 and S705. It should be noted that S704 and S705 are optional steps, that is, S704 and S705 may not be executed or exist, and then S706 is executed after S703. For example, in the case where the target access network device is the same access network device as the access network device a or the access network device B, S704 and S705 need not be performed.

S706, the access network device a sends a message4 to the terminal device a.

Wherein, the message4 includes the target cell information. Wherein the target cell information includes at least one of: physical cell identification of the target cell and frequency point information of the target cell. Optionally, the message4 may further include the reserved non-contention random access resource configuration information of the target cell. Further, the message4 may further include information for determining the key B and/or a second security algorithm. The information used to determine key B may include NCC. Alternatively, the NCC may be the NCC received by access network device a from access network device B. The second security algorithm may be the security algorithm that access network device a receives from the target access network device. It is understood that the message4 may not include information and/or security algorithm for the key B, and in this case, the terminal device a adopts the relevant information in the saved context by default.

S707, the terminal device a sends a fourth message to the target access device.

Wherein the fourth message is used for accessing the target access device. Optionally, the fourth message may be, for example, an RRC recovery complete message or an RRC reconfiguration complete message. In one possible approach, this fourth message may be secured, for example, using key B (which may also be referred to as a new key). Key B may be determined from the information of key a, NCC and the target cell.

In the embodiment of the application, the appropriate target access network equipment is determined for the terminal equipment in time in the connection recovery or reestablishment process of the terminal equipment, so that the service is better provided for the terminal equipment.

An embodiment of the present application further provides a communication method, as shown in fig. 8, which may include:

s801, the terminal device a sends an advance measurement report to the access network device a.

S802, the access network device a sends a fifth message to the access network device B.

The fifth message may carry part or all of the content of the advance measurement report received by the access network device a from the terminal device a.

Or the fifth message may carry information of the target access network device and/or the target cell, which is used by the access network device B to identify the target access network device and/or the target cell.

S803, the access network device B sends a sixth message to the target access network device.

Wherein the sixth message is a message for implementing a handover request.

The target access network device may be determined by access network device B based on some or all of the contents of the advance measurement report received from access network device a; alternatively, the target access network device may be determined by access network device a and then sent to access network device B.

Wherein, the sixth message carries a target key (a key used in communication between the terminal device a and the target cell). Optionally, the sixth message may further include information of the target cell, and further may further include a measurement result of the target cell.

As one implementation, the target key is determined by the following method: the access network equipment B determines a first key according to an old key when the terminal equipment A and the access network equipment B carry out service transmission and cell information of an access request initiated by the terminal equipment A (the cell belongs to the access network equipment A); and then the access network equipment B determines a target key according to the first key and the target cell information.

Optionally, the sixth message may further include a target NCC (NCC used in communication between the terminal device a and the target cell).

S804, the target access network device replies a response of the sixth message to the access network device B.

The response may carry a target security algorithm selected by the target access network device.

S805, the access network device B sends a response message of the fifth message to the access network device a.

Wherein, the response message may carry the target cell information. Optionally, the response message may also carry the reserved non-contention random access resource configuration information of the target cell.

Optionally, the response message may also carry information used by the terminal device a to determine the target key and/or the target security algorithm. The information used to determine the target key may include the target NCC.

S806, the access network device a sends a message4 to the terminal device a.

S807, the terminal device a sends a fourth message to the target access device.

For S806 and S807, reference may be made to the related descriptions in S706-S707, and details are not repeated here.

It is to be understood that, in the above embodiments, the method and/or the step implemented by the terminal device may also be implemented by a component (e.g., a chip or a circuit) available for the terminal device, the method and/or the step implemented by the access network device (e.g., the first access network device, the second access network device, the access network device a, or the access network device B), the method and/or the step implemented by the access network device, the core network device, or the core network node, and the component available for the core network device or the core network node.

It is understood that, in the embodiments of the present application, the terminal device and/or the access network device may perform some or all of the steps in the embodiments of the present application, and these steps or operations are merely examples, and the embodiments of the present application may also perform other operations or various modifications of the operations. Further, the various steps may be performed in a different order presented in the embodiments of the application, and not all operations in the embodiments of the application may be performed.

The above mainly introduces the solutions provided in the embodiments of the present application from the perspective of interaction between network elements. Correspondingly, the embodiment of the application also provides a communication device, and the communication device is used for realizing the various methods. The communication device may be the terminal device involved in the above method embodiments, or a device including the above terminal device, or a component that can be used for the terminal device; alternatively, the communication device may be an access network device (e.g., a first access network device, a second access network device, an access network device a, or an access network device B) involved in the foregoing various method embodiments, or a device including the above access network device, or a component that can be used for the access network device; alternatively, the communication device may also be a core network node involved in the foregoing method embodiments, or a device including the foregoing core network node, or a component that can be used for a core network node. It is understood that the communication device comprises hardware structures and/or software modules for performing the respective functions in order to realize the functions. Those of skill in the art will readily appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is performed in hardware or computer software drives hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the embodiment of the present application, the communication apparatus may be divided into functional modules according to the method embodiments, for example, each functional module may be divided corresponding to each function, or two or more functions may be integrated into one processing module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. It should be noted that, in the embodiment of the present application, the division of the module is schematic, and is only one logic function division, and another division manner may be available in actual implementation.

For example, the communication device is taken as the first access network device in the above method embodiment. Fig. 9 shows a schematic structural diagram of a communication device 90. The communication device 90 includes a transmitting module 901 and a receiving module 902. The sending module 901 and the receiving module 902 may exist independently in the form of an interface, or may be integrated into a transceiving module, which may also be referred to as a transceiving unit to implement sending and/or receiving functions, for example, may be a transceiving circuit, a transceiver, or a communication interface.

All relevant contents of the steps related to the above method embodiments may be referred to as a functional description of the corresponding functional module, which is exemplified below and not described in detail herein.

For example, the sending module 901 may be configured to send the first message to the second access network device, where reference may be made to the description of the foregoing embodiment for the first message.

A receiving module 902 may be configured to receive a response message of the first message from the second access network device.

Optionally, the receiving module 902 may be further configured to receive a measurement report and service information from the terminal device.

Optionally, the access network device 90 may further include a processing module 903, configured to determine the second access network device according to the measurement report and the service information.

Optionally, the sending module 901 may be further configured to send, by the terminal device, the content of the security mode command message and the content of the RRC reconfiguration message.

Optionally, the receiving module 902 may further receive second indication information from the second access network device, where the second indication information indicates that the first access network device does not receive the response message of the security mode command message.

Optionally, the receiving module 902 may be further configured to receive a response message of the security mode command message from the terminal device.

Optionally, in the case that the advanced measurement report is sent through a message or signaling before message 4: the receiving module 902 may further be configured to receive a random access preamble from the terminal device, the processing module 903 is configured to determine a pre-measurement report to be sent by the terminal device according to information of the random access preamble, and the sending module 901 may be configured to send a random access response (message 2) to the terminal device, where the random access response includes uplink scheduling information for the pre-measurement report. It is to be understood that the structures and interactions between the modules involved in this case may also be implemented independently.

A "module" in embodiments of the present application may refer to an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor and memory that execute one or more software or firmware programs, an integrated logic circuit, and/or other devices that may provide the described functionality. In a simple embodiment, the communication means 90 may be in the form of an access network device 20 according to fig. 2, as will be appreciated by those skilled in the art.

For example, the processor 201 in the access network device 20 shown in fig. 2 may cause the access network device 20 to execute the communication method in the above-described method embodiment by calling a computer stored in the memory 202 to execute the instructions.

In one possible manner, the functions/implementation procedures of the sending module 901 and the receiving module 902 in fig. 9 may be implemented by the processor 201 in the access network device 20 shown in fig. 2 calling the computer execution instructions stored in the memory 202. Alternatively, the functions/implementation procedures of the sending module 901 and the receiving module 902 in fig. 9 may be implemented by the transceiver 203 in the access network device 20 shown in fig. 2, and the functions/implementation procedures of the processing module 903 in fig. 9 may be implemented by the processor 201 described in fig. 2.

Since the communication apparatus 90 provided in this embodiment can perform the above-mentioned communication method, the technical effects obtained by the communication apparatus can refer to the above-mentioned method embodiment, and are not described herein again.

For example, the communication device is taken as the second access network device in the above method embodiment. Fig. 10 shows a schematic structural diagram of a communication device 1000. The communication device 1000 includes a receiving module 1001 and a transmitting module 1002. The receiving module 1001 and the sending module 1002 may exist independently in the form of an interface, or may be integrated into a transceiving module, which may also be referred to as a transceiving unit to implement a sending and/or receiving function, for example, may be a transceiving circuit, a transceiver, or a communication interface.

All relevant contents of each step related to the above method embodiment may be referred to the functional description of the corresponding functional module, which is exemplified below and will not be described in detail herein.

For example, the receiving module 1001 may be configured to receive a first message from a first access network device, where the first message includes identification information of a terminal device, a reason for the terminal device to initiate a radio resource control, RRC, connection establishment, and identification information of a public land mobile network, PLMN, selected by the terminal device.

The sending module 1002 may be configured to send a response message (first response message) of the first message to the first access network device.

In a possible manner, the first response message sent by the sending module 1002 may further include information of the first key.

Optionally, the sending module 1002 may further send second indication information to the first access network device, where the second indication information indicates that the first access network device does not receive the second response message.

Optionally, the receiving module 1001 may be further configured to receive a second response message from the terminal device.

Optionally, the receiving module 1001 may be further configured to receive a third response message from the terminal device.

For the related description of each message, reference may be made to the related description in the method embodiment, and details are not repeated here.

In this embodiment, a "module" may refer to an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor and memory that execute one or more software or firmware programs, an integrated logic circuit, and/or other devices that provide the described functionality. In a simple embodiment, those skilled in the art will appreciate that the communication apparatus 1000 may be in the form of an access network device 20 as shown in fig. 2.

In one possible approach, the functions/implementation procedures of the receiving module 1001 and the sending module 1002 in fig. 10 may be implemented by the processor 201 in the access network device 20 shown in fig. 2 calling the computer execution instructions stored in the memory 202. Alternatively, the functions/implementation procedures of the receiving module 1001 and the sending module 1002 in fig. 10 may be implemented by the transceiver 203 in the access network device 20 shown in fig. 2.

For example, the communication device is taken as the terminal device in the above method embodiment. Fig. 11 shows a schematic structural diagram of a communication device 11. The communication device 11 includes a transmitting module 1101 and a receiving module 1102. The sending module 1101 and the receiving module 1102 may be independent in the form of an interface, or may be integrated into a transceiving module, which may also be referred to as a transceiving unit to implement a sending and/or receiving function, for example, may be a transceiving circuit, a transceiver, or a communication interface.

For example, the receiving module 1102 may be configured to receive a security mode command message from the first access network device, where content of the security mode command message is consistent with content of a security mode message determined by the second access network device, the security mode command message includes information of a first key, and the first key is determined according to an initial key determined by a core network, a physical cell identifier of a source cell, and a source cell frequency point, where the source cell belongs to the first access network device.

And the sending module 1101 is configured to send a response message of the security mode command message, where the response message of the security mode command may be sent to the first access network device or the second access network device.

Further, optionally, the sending module 1101 may be further configured to send the measurement report and the traffic information to the first access network device.

Optionally, the sending module 1101 may be further configured to send a second message indicating that the radio resource control RRC reconfiguration is completed to the second access network device.

Optionally, the receiving module 1102 may be further configured to receive first indication information from the first access network device, where the first indication information is used to indicate a response message for sending the security mode command message to the second access network device. In a possible manner, in case of receiving the first indication information, the sending module 1101 sends a response message of the security mode command message to the second access network device.

In one possible approach, in case the advance measurement report is sent by signaling or messaging before message 4: the sending module 1101 may be further configured to send a random access preamble to the first access network device, the receiving module 1102 may be configured to receive a random access response (message 2) from the first access network device, where the random access response includes uplink scheduling information for the advanced measurement report, and the sending module 1101 is configured to send the advanced measurement report to the first access network device according to the uplink scheduling information received by the receiving module 1102. It is to be understood that the structures and interactions between the modules involved in this case may also be implemented independently.

In this embodiment, a "module" may refer to an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor and memory that execute one or more software or firmware programs, an integrated logic circuit, and/or other devices that provide the described functionality. In a simple embodiment, the person skilled in the art realises that the communication means 11 may be in the form of a terminal device 30 according to fig. 2.

For example, the processor 301 in the terminal device 30 shown in fig. 2 may execute the instructions by calling a computer stored in the memory 302, so that the terminal device 30 executes the communication method in the above-described method embodiment.

In a possible manner, the functions/implementation procedures of the sending module 1101 and the receiving module 1102 in fig. 11 can be implemented by the processor 301 in the terminal device 30 shown in fig. 2 calling the computer execution instructions stored in the memory 302. Alternatively, the functions/implementation procedures of the transmitting module 1101 and the receiving module 1102 in fig. 11 may be implemented by the transceiver 303 in the terminal device 30 shown in fig. 2.

The embodiment of the present application further provides a communication apparatus, configured to implement the relevant function/implementation process of the first node in the foregoing method embodiment. For example, the communication apparatus may include a sending module configured to send, to a core network node, a message for delivering non-access stratum signaling of the terminal device to the core network node, and a receiving module configured to receive a response message from the core network node, and further, the sending module may send, to the core network node, a message including an initial context setup response, a session resource identifier, and address information for transmitting downlink data of the session resource after RRC reconfiguration of the terminal device is completed. It should be noted that the sending module and the receiving module may exist independently in the form of an interface, or may be integrated into a transceiving module, and the transceiving module may also be referred to as a transceiving unit to implement a sending and/or receiving function, for example, the transceiving module may be a transceiving circuit, a transceiver, or a communication interface.

The embodiment of the present application further provides a communication apparatus, configured to implement the relevant function/implementation process of the core network node in the foregoing method embodiment. For example, the communications apparatus may include means for receiving a message from a first node conveying non-access stratum signaling for a terminal device to a core network node; and a sending module, configured to send a response message to the first node, and further, after the RRC reconfiguration of the terminal device is completed, the receiving module is configured to receive, from the first node, a message that includes an initial context setup response, a session resource identifier, and address information for transmitting downlink data of the session resource. The sending module and the receiving module may exist independently in the form of an interface, or may be integrated into a transceiving module, which may also be referred to as a transceiving unit to implement a sending and/or receiving function, and may be, for example, a transceiving circuit, a transceiver, or a communication interface.

The embodiment of the present application further provides a communication apparatus, which includes a module for implementing the relevant functions/implementation processes corresponding to the access network device a in the embodiment shown in fig. 7 or fig. 8. For example, for the sending module and the receiving module, for specific interaction between the sending module and the receiving module, reference may be made to steps related to sending and receiving in the method embodiment, and details are not described here again.

The embodiment of the present application further provides a communication apparatus, which includes a module for implementing the relevant functions/implementation procedures corresponding to the access network device B in the embodiment shown in fig. 7 or fig. 8. For example, for the sending module and the receiving module, for the specific interaction between the sending module and the receiving module, reference may be made to the steps related to sending and receiving in the method embodiment, and details are not described here again.

The embodiment of the present application further provides a communication apparatus, which includes a module for implementing the relevant functions/implementation procedures corresponding to the target access network device in the embodiment shown in fig. 7 or fig. 8. For example, for the sending module and the receiving module, for specific interaction between the sending module and the receiving module, reference may be made to steps related to sending and receiving in the method embodiment, and details are not described here again.

The embodiment of the present application further provides a communication apparatus, which includes a module for implementing the relevant function/implementation process corresponding to the terminal device a in the embodiment shown in fig. 7 or fig. 8. For example, for the sending module and the receiving module, for the specific interaction between the sending module and the receiving module, reference may be made to the steps related to sending and receiving in the method embodiment, and details are not described here again.

Optionally, an embodiment of the present application further provides a communication device (for example, the communication device may be a chip or a system-on-chip), where the communication device includes a processor, and is configured to implement the method in any of the above method embodiments. In one possible design, the communication device further includes a memory. The memory for storing the necessary program instructions and data, the processor may call the program code stored in the memory to instruct the communication device to perform the method of any of the above-described method embodiments. Of course, the memory may not be in the communication device. When the communication device is a chip system, the communication device may be composed of a chip, or may include a chip and other discrete devices, which is not specifically limited in this embodiment of the present application.

In the above embodiments, all or part of the implementation may be realized by software, hardware, firmware, or any combination thereof. When implemented using a software program, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. The procedures or functions described in accordance with the embodiments of the present application are all or partially generated upon loading and execution of computer program instructions on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website, computer, server, or data center to another website, computer, server, or data center via wire (e.g., coaxial cable, fiber optic, digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or can comprise one or more data storage devices, such as servers, data centers, and the like, that can be integrated with the medium. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid State Disk (SSD)), among others. In the embodiment of the present application, the computer may include the foregoing apparatus.

While the present application has been described in connection with various embodiments, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed application, from a review of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Although the present application has been described in conjunction with specific features and embodiments thereof, it will be evident that various modifications and combinations can be made thereto without departing from the spirit and scope of the application. Accordingly, the specification and drawings are merely illustrative of the present application as defined in the appended claims and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of the application. It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

Claims

1. A communication method applied to a communication system including a first access network device and a second access network device, the method comprising:

a first access network device sends a first message to a second access network device, wherein the first message comprises identification information of a terminal device, a reason for the terminal device to initiate Radio Resource Control (RRC) connection establishment and identification information of a Public Land Mobile Network (PLMN) selected by the terminal device;

and the second access network equipment sends a response message of the first message to the first access network equipment.

2. A method of communication, comprising:

the method comprises the steps that a second access network device receives a first message from a first access network device, wherein the first message comprises identification information of a terminal device, a reason for the terminal device to initiate Radio Resource Control (RRC) connection establishment and identification information of a Public Land Mobile Network (PLMN) selected by the terminal device;

3. The method according to claim 1 or 2,

the second access network device is determined by the first access network device according to the measurement report and the service information.

4. The method according to claim 3, wherein the traffic information comprises registered target core network node identification information and/or a list of single network slice selection support information.

5. The method according to any of claims 1-4, wherein the response message of the first message is used to determine that the terminal device is allowed to access, and the response message of the first message comprises the content of a security mode command message and the content of an RRC reconfiguration message.

6. The method of claim 5, wherein the content of the RRC reconfiguration message is security protected according to an initial key and a security algorithm, wherein the initial key is from a core network.

7. The method of claim 5, wherein the content of the RRC reconfiguration message is security protected according to a first key and a security algorithm, wherein the first key is determined according to an initial key from a core network and information of a source cell, wherein the source cell belongs to the first access network device, and wherein the information of the source cell comprises at least one of a physical cell identifier of the source cell and a frequency point of the source cell.

8. The method according to claim 7, wherein the content of the security mode command message in the response message of the first message includes information of the first key, wherein the information of the first key includes first key indication information or a first key, and the first key indication information is used to instruct the terminal device to determine the first key according to the initial key and information of a source cell.

9. The method according to any of claims 5-8, wherein the content of the security mode command message in the response message of the first message includes first indication information, and the first indication information is used to instruct the terminal device to send the response message of the security mode command message to the second access network device.

10. The method of claim 9, further comprising the second access network device sending second indication information indicating that the first access network device does not receive the response message of the security mode command message from the terminal device.

11. The method of claim 3, wherein the measurement report is an advanced measurement report.

12. A method of communication, comprising:

receiving a security mode command message from a first access network device, wherein the content of the security mode command message is consistent with the content of a security mode message determined by a second access network device, the security mode command message includes information of a first key, the first key is determined according to an initial key determined by a core network and information of a source cell, wherein the source cell belongs to the first access network device, and the information of the source cell includes at least one of a physical cell identifier of the source cell and a frequency point of the source cell;

and sending a response message of the security mode command message, wherein the response message of the security mode command is security-protected according to the first secret key.

13. The method according to claim 12, wherein the information of the first key includes first key indication information or a first key, and the first key indication information is used to indicate that the first key is determined according to the initial key, a physical cell identifier of a source cell, and a frequency point of the source cell.

14. The method of claim 12 or 13, further comprising:

and sending a second message indicating that Radio Resource Control (RRC) reconfiguration is completed to the second access network equipment, wherein the second message is subjected to security protection according to a second key, the second key is determined according to the first key and information of a target cell, the target cell belongs to the second access network equipment, and the information of the target cell comprises at least one of a physical cell identifier of the target cell and a frequency point of the target cell.

15. The method according to any one of claims 12-14, further comprising: receiving first indication information from the first access network device, wherein the first indication information is used for indicating a response message of the security mode command message sent to the second access network device;

the response message to send the security mode command message includes: sending a response message to the second access network device to the security mode command message.

16. The method according to any of claims 12-15, wherein said sending a response message to said secure mode command message comprises: sending a response message to the first access network device to the security mode command message.

17. The method of any of claims 12-16, wherein prior to receiving the security mode command message from the first access network device, further comprising: an advance measurement report is sent to the first access network device.

18. The method of claim 17, wherein in the case that the advanced measurement report is sent before a collision resolution message, the method further comprises:

sending a random access preamble (message 1) to the first access network device indicating the advance measurement report to be sent;

receiving a random access response (message 2) from the first access network device, wherein the random access response includes uplink scheduling information for the advanced measurement report;

the sending of the advance measurement report to the first access network device includes:

and sending the advanced measurement report to the first access network equipment according to the uplink scheduling information.

19. The method of claim 18, further comprising: indicating to the first access network device that the advanced measurement report did not send full information.

20. A communication device arranged to implement the method of any of claims 2 to 11.

21. A communication device arranged to implement the method of any of claims 12 to 19.

22. A communication system for implementing the method of any of claims 1 or 3-11.

23. A computer-readable storage medium comprising instructions that, when executed, cause a method according to any one of claims 1-19 to be performed.