CN115707029A - Communication method and communication device - Google Patents

Abstract

The present application provides a communication method and a communication device. The method includes: after the first IAB node receives the first RRC message from the IAB host CU and the first IAB node switches from the source parent node of the first IAB node to the target parent node of the first IAB node according to the first RRC message , and then send a second RRC message to the second IAB node to trigger the second IAB node to perform transport network layer migration according to the second RRC message, avoiding the successful switching of the second IAB node to access the first IAB node at the first IAB node The target parent node of the node starts to perform the transport network layer migration before, so it can avoid the migration failure caused by the premature execution of the transport network layer migration of the second IAB node, thereby reducing the service delay impact on the terminal served by the IAB node, and can Improve communication efficiency.

Description

A communication method and communication device

technical field

The present application relates to the technical field of communication, and in particular, to a communication method and a communication device.

Background technique

At present, in the integrated access and backhaul (IAB) network, the topology update of the IAB network is allowed, for example, an IAB node is switched from the source parent node to the target parent node, and the IAB is further completed after the switch The transport network layer (transport network layer, TNL) migration (migrating) of the node and the subordinate nodes of the IAB node, so as to complete the topology update. Wherein, the subordinate nodes of the IAB node are also IAB nodes, including child nodes and grandchildren nodes of the IAB node.

However, there is currently no good method for when to trigger the subordinate nodes of the IAB node to perform transport network layer migration so as to reduce the service delay impact on the terminals served by the IAB node.

Contents of the invention

The present application provides a communication method and a communication device, which are used to trigger IAB nodes to perform transmission network layer migration at an appropriate time, so as to reduce the impact of service delay on terminals served by IAB contacts, thereby improving communication efficiency.

In the first aspect, the embodiment of the present application provides a communication method, which can be executed by a first IAB node or a module (such as a chip) applied to the first IAB node, where the first IAB node is a migration IAB node. Taking the method performed by the first IAB node as an example, the first IAB node determines that the first condition is met, and the first condition includes: the first IAB node receives the first RRC message from the IAB host CU, and the first IAB node Handover from the source parent node of the first IAB node to the target parent node of the first IAB node according to the first RRC message. When the first condition is met, the first IAB node sends indication information to the second IAB node, where the indication information is used to trigger the second RRC message in the second IAB node to take effect. Or, when the first condition is satisfied, the first IAB node sends the second RRC message to the second IAB node. Wherein, the first RRC message includes first configuration information, the first configuration information is used for transport network layer migration between the first IAB node and the IAB host CU, and the second RRC message includes second configuration information, the The second configuration information is used for transport network layer migration between the second IAB node and the IAB host CU. The second IAB node is a child node of the first IAB node, the source parent node and the target parent node are connected to different IAB host DUs, and the first IAB node is connected to the IAB host DU through the different IAB host DUs before and after switching The IAB hosts the CU.

According to the above scheme, after the first IAB node receives the first RRC message from the IAB host CU and the first IAB node switches from the source parent node of the first IAB node to the target parent node of the first IAB node according to the first RRC message , and then send a second RRC message to the second IAB node to trigger the second IAB node to perform transport network layer migration according to the second RRC message, avoiding the successful switching of the second IAB node to access the first IAB node at the first IAB node The target parent node of the node starts to perform the transport network layer migration before, so it can avoid the migration failure caused by the premature execution of the transport network layer migration of the second IAB node, thereby reducing the service delay impact on the terminal served by the IAB node, and can Improve communication efficiency.

As a possible implementation method, the first condition further includes: the first IAB node has not received the first information from the IAB host CU, the first information is used for data transmission after the first IAB node switches, the The first information includes one or more of BAP route mapping configuration, BH RLC CH mapping configuration, or BAP route identification configuration.

According to the above solution, it is limited that the first IAB node sends the second RRC message to the second IAB node before receiving the first information from the IAB host node-CU, so that the second IAB node can start to perform transport network layer migration as early as possible, thereby reducing The impact on the service delay of the terminal served by the IAB contact can improve communication efficiency.

As a possible implementation method, the first condition further includes: the first IAB node has not completed the transport network layer migration between the first IAB node and the IAB host CU according to the first configuration information.

According to the above scheme, it is avoided that the first IAB node starts to send the second RRC message to the second IAB node after completing the transfer of the transport network layer, so it is possible to prevent the second IAB node from performing the transfer of the transport network layer too late and causing the terminal's service Interrupt latency is too long.

As a possible implementation method, different IAB host DUs connected to the source parent node and the target parent node belong to the IAB host CU, and the first configuration information includes the first BAP routing identifier. The first IAB node receives the uplink data packet, and the uplink data packet includes the second BAP routing identifier. When the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, the first IAB node sends the uplink data packet according to the first BAP routing identifier.

According to the above scheme, after the migrating IAB node is switched to the target parent node, and before the migration of the transmission network layer between the migrating IAB node and the IAB host node-CU is completed, after the first IAB node receives the uplink data packet, if the uplink The BAP address in the data packet is the same as the BAP address in the first BAP routing identifier, then the first IAB node can use the first BAP routing identifier to route the uplink data packet. In this way, it can be ensured that the received uplink data packets are sent successfully and packet loss is avoided. In addition, it is also possible to transmit the uplink data packet as early as possible, thereby reducing the service interruption delay of the terminal.

As a possible implementation method, when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, and the first IAB node has not received the first information from the IAB host CU, The first IAB node sends the uplink data packet according to the first BAP routing identifier. Wherein, the first information is used for data transmission after the first IAB node switches, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration.

According to this scheme, before the BAP routing configuration information is received on the target path, the routing of the above-mentioned data packets cannot be performed according to the BAP routing configuration information on the target path, but the above-mentioned method of the application can be used, and the first IAB node uses its own The received uplink data packet is routed with the first BAP routing identifier, so as to ensure that the received uplink data packet is successfully sent and avoid packet loss. As a possible implementation method, the IAB host DU connected to the source parent node belongs to the IAB host CU, and the IAB host DU connected to the target parent node belongs to another IAB host CU different from the IAB host CU. A configuration message includes a first BAP routing identifier. The first IAB node receives the uplink data packet, and the uplink data packet includes the second BAP routing identifier. When the BAP address in the second BAP routing identifier is the same as the BAP address allocated by the IAB host CU to the first IAB node, the first IAB node replaces the second BAP routing identifier in the downlink data packet with the first A BAP routing identifier. The first IAB node sends the uplink data packet according to the first BAP routing identifier.

According to the above scheme, after the migrating IAB node is switched to the target parent node, and before the migration of the transmission network layer between the migrating IAB node and the IAB host node-CU is completed, after the first IAB node receives the uplink data packet, if the uplink The BAP address in the data packet is the same as the BAP address of the first IAB node, indicating that the first IAB node needs to replace the BAP routing identifier in the uplink data packet, so the first IAB node uses the first BAP route of the first IAB node Identifies the routing of the uplink data packet. In this way, it can be ensured that the received uplink data packets are sent successfully and packet loss is avoided. In addition, it is also possible to transmit the uplink data packet as early as possible, thereby reducing the service interruption delay of the terminal.

As a possible implementation method, when the BAP address in the second BAP routing identifier is the same as the BAP address of the first IAB node, and the first IAB node has not received the first information from the IAB host CU, the first IAB node An IAB node sends the uplink data packet according to the first BAP routing identifier. Wherein, the first information is used for data transmission after the first IAB node switches, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration.

According to this scheme, before the BAP routing configuration information is received on the target path, the routing of the above-mentioned data packets cannot be performed according to the BAP routing configuration information on the target path, but the above-mentioned method of the application can be used, and the first IAB node uses its own The received uplink data packet is routed with the first BAP routing identifier, so as to ensure that the received uplink data packet is successfully sent and avoid packet loss.

As a possible implementation method, the first configuration information further includes the identifier of the BH RLC CH. The first IAB node determines a next-hop node of the first IAB node corresponding to the first BAP routing identifier. The first IAB node sends the uplink data packet to the next-hop node on the BHRLC CH.

As a possible implementation method, the next-hop node is the default parent node of the first IAB node. Alternatively, the first configuration information further includes the identifier of the next-hop node.

As a possible implementation method, the different IAB host DUs connected to the source parent node and the target parent node belong to the IAB host CU, and the first IAB node receives the downlink data packet, which contains the third BAP routing identifier. The first IAB node determines that the first RRC message has been received, and the first IAB node has not received the first information from the IAB host CU, and determines the first IAB node according to the BAP address in the third BAP routing identifier next hop node. The first IAB node sends the downlink data packet to the next-hop node. Wherein, the first information is used for data transmission after the first IAB node switches, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration.

According to the above scheme, after the migration IAB node is switched to the target parent node, and before the migration of the transmission network layer between the migration IAB node and the IAB host node-CU is completed, after the first IAB node receives the downlink data packet, when it is determined that the The rerouting trigger condition is to perform rerouting according to the BAP address in the third BAP routing identifier. In this way, it can be ensured that the received downlink data packets are sent successfully and packet loss is avoided. In addition, it is also possible to transmit the downlink data packet as early as possible, reducing the service interruption delay of the terminal.

As a possible implementation method, the IAB host DU connected to the source parent node belongs to the IAB host CU, and the IAB host DU connected to the target parent node belongs to another IAB host CU different from the IAB host CU. A configuration message includes a fourth BAP routing identifier. The first IAB node receives a downlink data packet, the downlink data packet includes a third BAP routing identifier, and the BAP address in the third BAP routing identifier is the BAP address of the first IAB node. The first IAB node replaces the third BAP routing identifier in the downlink data packet with the fourth BAP routing identifier. The first IAB node determines that the first RRC message has been received, and the first IAB node has not received the first information from the IAB host CU, and determines the first IAB node according to the BAP address in the fourth BAP routing identifier next hop node. The first IAB node sends the downlink data packet to the next-hop node. Wherein, the first information is used for data transmission after the first IAB node switches, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration.

According to the above scheme, after the migration IAB node is switched to the target parent node, and before the migration of the transmission network layer between the migration IAB node and the IAB host node-CU is completed, after the first IAB node receives the downlink data packet, when it is determined that the The rerouting trigger condition is to perform rerouting according to the BAP address in the fourth BAP routing identifier. In this way, it can be ensured that the received downlink data packets are sent successfully and packet loss is avoided. In addition, it is also possible to transmit the downlink data packet as early as possible, reducing the service interruption delay of the terminal.

As a possible implementation method, the first configuration information includes a new IP address allocated for the first IAB node.

As a possible implementation method, the first configuration information includes the first BAP routing identifier. The first IAB node determines a next-hop node of the first IAB node corresponding to the first BAP routing identifier. The first IAB node sends an uplink data packet to the next-hop node, and the uplink data packet includes the first BAP routing identifier.

According to the above scheme, after the migrating IAB node is switched to the target parent node, and before the migration of the transport network layer between the migrating IAB node and the IAB host node-CU is completed, after the first IAB node generates an uplink data packet, it uses the first BAP The routing identifier routes the uplink data packet. In this way, it can be ensured that the received uplink data packets are sent successfully and packet loss is avoided. In addition, it is also possible to transmit the uplink data packet as early as possible, thereby reducing the service interruption delay of the terminal.

In the second aspect, the embodiment of the present application provides a communication method, which can be executed by the first IAB node or a module (such as a chip) applied to the first IAB node, where the first IAB node is the migration IAB node subordinate nodes. Taking the method performed by the first IAB node as an example, the first IAB node determines that the first condition is met, and the first condition includes: the first IAB node receives the first indication information or the first RRC message from the second IAB node, The second IAB node is a parent node of the first IAB node, and the first indication information is used to trigger the first RRC message in the first IAB node to take effect. When the first condition is met, the first IAB node sends second indication information to the third IAB node, where the second indication information is used to trigger a second RRC message in the third IAB node to take effect. Or, when the first condition is satisfied, the first IAB node sends the second RRC message to the third IAB node, and the third IAB node is a child node of the first IAB node. Wherein, the first RRC message includes first configuration information, the first configuration information is used for transport network layer migration between the first IAB node and the IAB host CU, and the second RRC message includes second configuration information, the first The second configuration information is used for transport network layer migration between the third IAB node and the IAB host CU, and the first IAB node is connected to the IAB host CU through different IAB host DUs before and after transport network layer migration.

According to the above solution, after the first IAB node receives the first RRC message or the first indication information from the second IAB node, it can start to perform the migration of the transport network layer on the one hand, and on the other hand, immediately transfer to the child nodes of the first IAB node Sending the second RRC message or the second instruction information to trigger the child nodes of the first IAB node to start performing the transport network layer migration as early as possible, which can avoid the terminal caused by the child nodes of the first IAB node performing the transport network layer migration too late The service interruption delay is too long, thereby reducing the impact on the service delay of the terminal served by the IAB contact, and improving communication efficiency.

As a possible implementation method, the first condition further includes: the first IAB node has not received the first information from the second IAB node, and the first information is used for the first IAB node after the migration of the transport network layer For data transmission, the first information includes one or more of BAP route mapping configuration, BH RLC CH mapping configuration, or BAP route identification configuration.

According to the above solution, it is limited that the first IAB node sends the second RRC message to the third IAB node before receiving the first information from the second IAB node, so that the third IAB node can start to perform transport network layer migration as early as possible, avoiding the first The sub-nodes of the IAB node perform the migration of the transport network layer too late, resulting in too long service interruption delay of the terminal, thereby reducing the impact of service delay on the terminal served by the IAB node, and improving communication efficiency.

As a possible implementation method, the first condition further includes: the first IAB node has not completed the transport network layer migration between the first IAB node and the IAB host CU according to the first configuration information.

According to the above solution, it is avoided that the first IAB node starts to send the second RRC message to the third IAB node after completing the transfer of the transport network layer, so it is possible to prevent the third IAB node from performing the transfer of the transport network layer too late and causing the terminal's service The interruption delay is too long, thereby reducing the service delay impact on the terminal served by the IAB contact, and improving communication efficiency.

As a possible implementation method, the first configuration information includes the first BAP routing identifier. The first IAB node receives the uplink data packet, and the uplink data packet includes the second BAP routing identifier. When the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, the first IAB node sends the uplink data packet according to the first BAP routing identifier.

According to the above scheme, after the migrating IAB node is switched to the target parent node, and before the migration of the transmission network layer between the migrating IAB node and the IAB host node-CU is completed, after the first IAB node receives the uplink data packet, if the uplink The BAP address in the data packet is the same as the BAP address in the first BAP routing identifier, then the first IAB node can use the first BAP routing identifier to route the uplink data packet. In this way, it can be ensured that the received uplink data packets are sent successfully and packet loss is avoided. In addition, it is also possible to transmit the uplink data packet as early as possible, thereby reducing the service interruption delay of the terminal.

As a possible implementation method, when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, and the first IAB node has not received the first information from the second IAB node , the first IAB node sends the uplink data packet according to the first BAP route identifier. Wherein, the first information is used for data transmission after the first IAB node switches, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration.

According to this scheme, before the BAP routing configuration information is received on the target path, the routing of the above-mentioned data packets cannot be performed according to the BAP routing configuration information on the target path, but the above-mentioned method of the application can be used, and the first IAB node uses its own The received uplink data packet is routed with the first BAP routing identifier, so as to ensure that the received uplink data packet is successfully sent and avoid packet loss.

As a possible implementation method, the first configuration information further includes the identifier of the BH RLC CH. The first IAB node determines a next-hop node of the first IAB node corresponding to the first BAP routing identifier. The first IAB node sends the uplink data packet to the next-hop node on the BHRLC CH.

As a possible implementation method, the next-hop node is the default parent node of the first IAB node. Alternatively, the first configuration information further includes the identifier of the next-hop node.

As a possible implementation method, the first IAB node receives the downlink data packet, and the downlink data packet includes the third BAP routing identifier. The first IAB node determines that the first RRC message has been received, and the first IAB node has not received the first information from the IAB host CU, and determines the first IAB node according to the BAP address in the third BAP routing identifier next hop node. The first IAB node sends the downlink data packet to the next-hop node. Wherein, the first information is used for data transmission after the first IAB node switches, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration.

According to the above scheme, after the migration IAB node is switched to the target parent node, and before the migration of the transmission network layer between the migration IAB node and the IAB host node-CU is completed, after the first IAB node receives the downlink data packet, when it is determined that the The rerouting trigger condition is to perform rerouting according to the BAP address in the third BAP routing identifier. In this way, it can be ensured that the received downlink data packets are sent successfully and packet loss is avoided. In addition, it is also possible to transmit the downlink data packet as early as possible, reducing the service interruption delay of the terminal.

As a possible implementation method, the first configuration information includes a new IP address allocated for the first IAB node.

In a third aspect, the embodiment of the present application provides a communication device, and the device may be an IAB node, or may be a chip for the IAB node. The device has the function of realizing any realization method of the above-mentioned first aspect to the second aspect. This function may be implemented by hardware, or may be implemented by executing corresponding software on the hardware. The hardware or software includes one or more modules corresponding to the above functions.

In a fourth aspect, the embodiment of the present application provides a communication device, including a processor and a memory; the memory is used to store computer instructions, and when the device is running, the processor executes the computer instructions stored in the memory so that the device executes Any implementation method in the first aspect to the second aspect above.

In a fifth aspect, the embodiment of the present application provides a communication device, including a unit or means (means) for performing each step of any implementation method in the first aspect to the second aspect.

In a sixth aspect, an embodiment of the present application provides a communication device, including a processor and an interface circuit, the processor is configured to communicate with other devices through the interface circuit, and execute any implementation method in the first aspect to the second aspect above. The processor includes one or more.

In the seventh aspect, the embodiment of the present application provides a communication device, including a processor coupled to the memory, and the processor is used to call the program stored in the memory to execute any implementation method in the first aspect to the second aspect above . The memory may be located within the device or external to the device. And there may be one or more processors.

In the eighth aspect, the embodiment of the present application also provides a computer-readable storage medium, where instructions are stored in the computer-readable storage medium, and when the computer-readable storage medium is run on a communication device, the above-mentioned first aspect to the second aspect Any implementation method is executed.

In the ninth aspect, the embodiment of the present application further provides a computer program product, the computer program product includes computer programs or instructions, and when the computer programs or instructions are run by the communication device, any of the above first to second aspects can be realized method is executed.

In a tenth aspect, the embodiment of the present application further provides a chip system, including: a processor, configured to execute any implementation method in the above-mentioned first aspect to the second aspect.

Description of drawings

Figure 1 is a schematic diagram of an IAB independent networking scenario;

Figure 2 is a schematic diagram of an IAB non-independent networking scenario;

Fig. 3 is a schematic diagram of the IAB network user plane protocol stack;

Fig. 4 is a schematic diagram of the IAB network control plane protocol stack;

FIG. 5 is a schematic diagram of topology update in the IAB network host;

6 is a schematic diagram of IAB network cross-host topology update;

Fig. 7(a) is a schematic flow diagram of the communication method provided by the embodiment of the present application;

FIG. 7(b) is a schematic flow diagram of the communication method provided by the embodiment of the present application;

FIG. 8(a) is a schematic flowchart of a communication method provided by an embodiment of the present application;

FIG. 8(b) is a schematic flow diagram of the communication method provided by the embodiment of the present application;

FIG. 9 is a schematic flowchart of a data transmission method provided in an embodiment of the present application;

FIG. 10 is a schematic flowchart of a data transmission method provided in an embodiment of the present application;

FIG. 11 is a schematic flowchart of a data transmission method provided in an embodiment of the present application;

FIG. 12 is a schematic flow diagram of a data transmission method provided in an embodiment of the present application;

FIG. 13 is a schematic flowchart of a data transmission method provided in an embodiment of the present application;

FIG. 14 is a schematic diagram of a communication device provided in an embodiment of the present application;

FIG. 15 is a schematic diagram of a communication device provided by an embodiment of the present application.

Detailed ways

Compared with the fourth generation (4th generation, 4G) mobile communication system, the fifth generation (5th generation, 5G) mobile communication puts forward more stringent requirements for various performance indicators of the network. For example, the capacity index has been increased by 1000 times, wider coverage requirements, ultra-high reliability and ultra-low latency, etc. On the one hand, considering the abundance of high-frequency carrier frequency resources, in hotspot areas, in order to meet the demand for 5G ultra-high capacity, the use of high-frequency small cell networking is becoming more and more popular. The propagation characteristics of high-frequency carriers are poor, the attenuation is serious due to occlusion, and the coverage area is not wide, so a large number of densely deployed small stations are required. Correspondingly, the cost of providing optical fiber backhaul for these densely deployed small cells is high, and the construction is difficult. Therefore, an economical and convenient backhaul solution is required. On the other hand, from the perspective of wide coverage requirements, it is difficult and costly to deploy optical fibers to provide network coverage in some remote areas, and it is also necessary to design flexible and convenient access and backhaul solutions. IAB technology provides an idea to solve the above two problems: its access link (access link) and backhaul link (backhaul link) both use wireless transmission solutions to avoid fiber deployment.

Referring to FIG. 1 , it is a schematic diagram of an IAB independent (standalone, SA) networking scenario. Wherein, both the IAB node and the user equipment (user equipment, UE) establish a connection with the network through an air interface of a new radio (new radio, NR) standard. In the IAB network, the IAB node (IAB node) can also be called a relay node (relay node, RN), which can provide wireless access services for the UE, and the service data of the UE is connected to the IAB by the IAB node through a wireless backhaul link Host node (IAB donor node) transmission. In this application, the IAB donor node may also be referred to as a donor node or a donor base station (donor gNodeB, DgNB).

The IAB node includes a mobile terminal (mobile termination, MT) part and a distributed unit (distributed unit, DU) part. The MT part of the IAB node has some or all functions of the UE, and can be used to provide data backhaul for its child nodes. The DU part of an IAB node can be used to provide access services for its child nodes. The MT part of the IAB node may be referred to as IAB-MT for short, and the DU part of the IAB node may be referred to as IAB-DU for short. The IAB node can communicate with the parent node of the IAB node through the MT part of the IAB node, and at this time, the IAB node is regarded as a UE. The IAB node can communicate with the child nodes of the IAB node through the DU part of the IAB node, and at this time the IAB node is regarded as a network device. The child node of the IAB node may be another IAB node or a normal UE.

The IAB nodes can be divided into access IAB nodes and intermediate IAB nodes, where the IAB nodes accessed by the UE are called access IAB nodes, and the IAB nodes on the path between the access IAB node and the IAB host node are called intermediate IAB nodes. For example, IAB node 4 and IAB node 5 in FIG. 1 are called access IAB nodes, and IAB node 1 , IAB node 2 and IAB node 3 are called intermediate IAB nodes.

The IAB host node may be an access network element having some or all functions of a base station, or an access network element including a centralized unit (centralized unit, CU) and a DU. The IAB host node can be connected to the core network serving the UE (for example, connected to the 5G core network), and provide the wireless backhaul function for the IAB node. In the embodiment of this application, the CU in the IAB host node can be called IAB host CU, IAB host node-CU, host node-CU or donor CU, and the DU of the IAB host node can be called IAB host DU, IAB host node -DU, host node-DU or donor DU. The donor CU may also be a form in which the control plane (control plane, CP) and the user plane (user plane, UP) are separated. For example, the donor CU includes one CU-CP and at least one CU-UP.

In this embodiment of the present application, a terminal may also be referred to as a terminal device, a UE, a mobile station, a mobile terminal, and the like. Terminals can be widely used in various scenarios, for example, device-to-device (device-to-device, D2D), vehicle-to-everything (V2X) communication, machine-type communication (machine-type communication, MTC), Internet of Things (Internet of Things) of things, IOT), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grid, smart furniture, smart office, smart wear, smart transportation, smart city, etc. Terminals can be mobile phones, tablet computers, computers with wireless transceiver functions, wearable devices, vehicles, drones, helicopters, airplanes, ships, robots, robotic arms, smart home devices, etc. The embodiment of the present application does not limit the specific technology and specific device form adopted by the terminal.

In the current 5G standard, considering the small coverage of the high-frequency band, in order to ensure the coverage performance of the network, multi-hop networking can be used in the IAB network. In addition, considering the requirements of service transmission reliability, IAB nodes can be enabled to support dual connectivity (DC) or multi-connectivity (multi-connectivity) to deal with possible abnormalities in the backhaul link. For example, abnormalities such as link interruption or blockage (blockage) and load fluctuations improve the reliability of transmission. Therefore, the IAB network supports multi-hop networking and can also support multi-connection networking. Between the UE served by the IAB node and the IAB host node, there is at least one transmission path composed of multiple links. A transmission path contains multiple nodes, such as UE, one or more IAB nodes and IAB host nodes (if the IAB host node is in the form of CU and DU separation, the IAB host node is replaced by the IAB host node-DU and IAB host Node-CU). Each IAB node regards the adjacent nodes that provide access and backhaul services to the IAB node as a parent node, and accordingly, each IAB node can be regarded as a child node of its parent node.

For example, in FIG. 1, the IAB host node is the parent node of the IAB node 1, and the IAB node 1 is the child node of the IAB host node. IAB node 1 is the parent node of IAB node 2 and IAB node 3 , and IAB node 2 and IAB node 3 are child nodes of IAB node 1 . IAB node 2 is the parent node of IAB node 4 and IAB node 5 , and IAB node 4 and IAB node 5 are child nodes of IAB node 2 . IAB node 3 is a parent node of IAB node 4, and IAB node 4 is a child node of IAB node 3.

In the uplink direction, the UE's uplink data packet can be transmitted to the IAB host node through one or more IAB nodes, and then sent to the mobile gateway device by the IAB host node (such as the user plane function (UPF) in the 5G core network) . In the downlink direction, the IAB host node sends the downlink data packet to the UE through the IAB node after receiving the downlink data packet from the mobile gateway device.

The IAB independent networking scenario shown in Figure 1 is only exemplary. In the IAB scenario combining multi-hop and multi-connection, there are more other possibilities. For example, the IAB host node in Figure 1 can communicate with another IAB The IAB node under the host node forms a dual connection to provide services for the UE, that is, the UE supports dual connectivity, and one of the connections 1 is that the UE accesses the cell served by the IAB host node-DU in Figure 1 through the IAB node in Figure 1. Another connection 2 is that the UE establishes a connection with the IAB node X, and the IAB host connected to the IAB node X is different from the IAB host node corresponding to the above connection 1.

Referring to FIG. 2 , it is a schematic diagram of an IAB non-standalone (NSA) networking scenario. The IAB node supports dual connectivity of 4G and 5G networks. The long term evolution (LTE) base station (i.e. eNB) is the master base station (mastereNB, MeNB). The eNB provides an LTE air interface (i.e. LTE Uu) connection for the IAB node, and is connected to the 4G core network, i.e. the evolved packet core The network (evolved packet core, EPC) establishes an S1 interface for user plane and control plane transmission. The IAB host node is a secondary base station, and the IAB host node can be a 5G gNB, which can provide an NR air interface (NR Uu) connection for the IAB node, and establish an S1 interface with the EPC for user plane transmission. The UE is connected to the primary base station (that is, eNB) through the LTE Uu interface, and connected to the secondary base station (which may be an IAB node or an IAB host node) through the NR Uu interface.

It should be noted that Figure 2 is only a networking example, and the NSA scenario of the IAB network also supports multi-hop IAB networking. For example, one or more IAB nodes can be added between the UE and the IAB node in Figure 2, that is, the IAB node It can be connected to the IAB host node through a multi-hop wireless backhaul link.

In the current IAB network, a new protocol layer is introduced into the wireless backhaul link, that is, the backhaul adaptation protocol (BAP) layer, and the BAP layer is located above the radio link control (radio link control, RLC) layer. It can be used to realize the routing of data packets on the wireless backhaul link, as well as bearer mapping and other functions.

An F1 interface is established between the DU part of the IAB node and the IAB host node-CU, and the F1 interface supports the user plane protocol (F1-U) and the control plane protocol (F1-C). Wherein, the user plane protocol includes one or more of the following protocols: General Packet Radio Service (General Packet Radio Service, GPRS) tunneling protocol user plane (GPRS tunnelingprotocol user plane, GTP-U) protocol, user datagram protocol (user datagram protocol , UDP), Internet Protocol (internet protocol, IP). The control plane protocol includes one or more of the following protocols: F1 application protocol (F1 application protocol, F1AP), stream control transport protocol (stream control transport protocol, SCTP), and IP protocol.

Referring to FIG. 3 , it is a schematic diagram of the IAB network user plane protocol stack. If the IAB host node adopts the CP-UP separation architecture, an F1-U interface is established between the DU part of the IAB node (IAB node 1 and IAB node 2 shown in FIG. 3 ) and the IAB host node-CU-UP. And for the access IAB node, a GTP tunnel with UE bearer granularity (per UE bearer) is also established on the F1-U interface between the access IAB node and the IAB host node-CU-UP. That is to say, each UE DRB established on the interface between the UE and the DU accessing the IAB node corresponds to a separate GTP on the F1-U interface between the accessing IAB node and the IAB host node-CU-UP tunnel.

Referring to FIG. 4 , it is a schematic diagram of the IAB network control plane protocol stack. If the IAB host node adopts the CP-UP separation architecture, an F1-C interface is established between the DU part of the IAB node (IAB node 1 and IAB node 2 as shown in FIG. 4 ) and the IAB host node-CU-CP. The radio resource control (radio resource control, RRC) message of the UE is encapsulated in the F1AP message of the F1-C interface for transmission.

Currently, IAB nodes are allowed to perform topology updates within the scope of a single IAB host node-CU service. Referring to FIG. 5 , it is a schematic diagram of topology update in the IAB network host. As the migration IAB node, IAB node 1 is connected to the source parent node before the topology update, and then due to the poor link quality or load sharing between IAB node 1 and the source parent node (ie IAB node 5), the IAB node A topology update is required. After the topology update, the IAB node 1 accesses the target parent node (ie, the IAB node 6 ), and communicates with the IAB host node via the target parent node.

Considering that in the IAB network, the IP address of the IAB node is related to the IAB host node-DU to which it is connected, therefore, if during the topology update process, the IAB host node-DU to which the target parent node of IAB node 1 is connected is the same as the IAB host node-DU The IAB host node-DU to which the source parent node of node 1 is connected is different, so IAB node 1 needs to be configured with different IP addresses before and after migration. That is, when IAB node 1 is connected to the source parent node, the IP address of IAB node 1 is related to IAB host node-DU 1, and even the IP address of IAB node 1 can be allocated by IAB host node-DU 1, and IAB node 1 When connecting to the target parent node, the IP address of the IAB node 1 is related to the IAB host node-DU 2, and even the IP address of the IAB node 1 can be assigned by the IAB host node-DU 2.

In addition to IAB node 1, the subordinate nodes of IAB node 1, such as its child node IAB node 2, grandchild node IAB node 4, etc., after following IAB node 1 to connect to IAB host node-DU 2, also need to be configured with a new IP address.

Wherein, the "grandchild node" in the embodiment of the present application refers to the child node of the child node. Taking Figure 5 as an example, the child node of IAB node 1 includes IAB node 2, and the child node of IAB node 2 includes IAB node 4, so The IAB node 4 is the grandson node of the IAB node 1 , correspondingly, the IAB node 1 can be called the grandparent node of the IAB node 4 . It is explained here uniformly, and will not be described in detail later.

In the embodiment of the present application, "the subordinate node of the migrating IAB node" includes the child node of the migrating IAB node and the nodes below the child node, or is understood as the IAB node on the transmission path between the UE and the migrating IAB node. Specifically, the subordinate nodes of the migrated IAB node include child nodes of the migrated node, grandchild nodes, child nodes of the grandchild nodes, grandchild nodes of the grandchild nodes, and so on, and so on. Taking FIG. 5 as an example, IAB node 1 is a relocated IAB node, and subordinate nodes of IAB node 1 include IAB node 2 , IAB node 3 and IAB node 4 . In the embodiment of the present application, the subordinate node of the migrating IAB node is also referred to as the subordinate IAB node of the migrating IAB node, or as the downstream node of the migrating IAB node, or as the downstream IAB node of the migrating IAB node. It is explained here uniformly, and will not be described in detail later. After the new IP address is configured, the IAB node can use the new IP address to establish a new transport network layer association (association) with the IAB host node-CU, and perform Internet protocol security (internet protocol security, IPsec) again. Security negotiation. Then migrate the F1-C connection between the DU part of the IAB node and the IAB host node CU and the GTP-U tunnel of F1-U to a new transmission path, and use a new IP address on the new transmission path .

In the embodiment of the present application, the IAB node uses a new IP address to establish a stream control transmission protocol (stream control transmission protocol, SCTP) layer connection (or called a transmission network layer coupling, or SCTP coupling) on a new transmission path , and/or the process of re-negotiating IPsec security is called transport network layer migration of the IAB node.

The transport network layer migration of the IAB node can also include any one or more of the following: the control plane of the F1 interface of the IAB node is carried on the SCTP layer coupling established on the new transmission path, and the F1 interface of the IAB node The user plane of the interface is migrated to the new transmission path. Wherein, when the control plane of the F1 interface of the IAB node is carried on the SCTP layer coupling established on the new transmission path, the new SCTP layer coupling will use a new IP address. When the user plane of the F1 interface of the IAB node is migrated to a new transmission path, the GTP-U tunnel at F1-U will use a new IP address.

Both the migration of the IAB node and the migration of the subordinate nodes of the IAB node need to perform transport network layer migration.

The above describes the process of the IAB node updating the topology within the service range of an IAB host node-CU. In another scenario, there is also a topology update problem of IAB node migration across IAB host nodes. Referring to FIG. 6 , it is a schematic diagram of IAB network cross-host topology update. Among them, IAB node 1 is the migration IAB node, IAB host node 1 is the source IAB host node, IAB host node 1 includes IAB host node-CU 1 and IAB host node-DU 1, IAB host node 2 is the target IAB host node, and IAB host node 1 is the target IAB host node. Host node 2 includes IAB host node-CU2 and IAB host node-DU2. Before the topology update, the migrated IAB node is connected to the source parent node (i.e. IAB node 5), which is managed by the source IAB host node. After the topology update, the migrated IAB node is connected to the target parent node (i.e. IAB node 6) , the target parent node is managed by the target IAB host node.

In this embodiment of the application, the migrated IAB node in the cross-host topology update scenario of the IAB network can also be called a border node. The source parent node and the target parent node of the border node are connected to different IAB host nodes-DU, and the different IAB The host node-DU belongs to a different IAB host node-CU, or there is an F1 interface between the different IAB host node-DU and a different IAB host node-CU.

As an implementation method, it can be considered to only update the MT part of the migrated IAB node to be managed by the target IAB host node (or the RRC connection of the MT part of the migrated IAB node is migrated to the target IAB host node), while the DU of the IAB node is migrated The part and its subordinate nodes are still controlled by the source IAB host node (or in other words, the DU part of the migrated IAB node and its subordinate nodes are still connected to the source IAB host node). For example, referring to Figure 6, before the topology update, IAB node 1 and the subordinate nodes of IAB node 1 are managed by IAB host node 1. After the topology update, the MT part of IAB node 1 is managed by IAB host node 2, and the IAB node 1’s The DU part and the subordinate nodes of the IAB node 1 are still managed by the IAB host node 1 . Based on this implementation method, since the parent node of the migrated IAB node is updated, the transmission path also changes. Therefore, after the topology update, the F1 connection between the DU part of the migrated IAB node and the IAB host node-CU1 needs to be migrated to the new On the transmission path, the new transmission path is shown in Figure 6, so it is necessary to perform the process of migration of the transmission network layer. Correspondingly, if the child nodes of the IAB node are migrated, the transfer network layer migration process also needs to be performed. That is to say, both the migrating IAB node and the subordinate nodes of the migrating IAB node need to execute the migration process of the transport network layer.

It can be seen from the above description that whether it is a topology update within a single IAB host or a topology update across IAB hosts, it is necessary to perform transport network layer migration on the migrated IAB node and the subordinate nodes of the migrated IAB node.

In order to realize the transfer of the transport network layer of the subordinate nodes of the migrated IAB node, the embodiment of the present application provides two different methods, which are as follows.

Implementation method 1. The IAB host node-CU first encapsulates the configuration information required for the subordinate nodes of the migrating IAB node to perform transport network layer migration in an RRC message, and sends the RRC messages of these subordinate nodes to each subordinate from the source transmission path in advance. The parent node of the node, the parent node will first cache these RRC messages, and then send them to the corresponding subordinate nodes after meeting the first condition (also called the trigger condition). After each IAB node receives its own RRC message, it performs configuration according to the configuration information in the RRC message, and initiates transport network layer migration.

The RRC message appearing anywhere in the embodiment of the present application may be an RRC configuration message or an RRC reconfiguration message, which are uniformly described here and will not be described in detail later.

Taking FIG. 5 as an example, the migrated IAB node is IAB node 1, and the subordinate nodes of IAB node 1 include IAB node 2, IAB node 3, and IAB node 4. The IAB host node-CU first carries the RRC message of IAB node 2 and the RRC message of IAB node 3 in the F1AP message sent to IAB node 1-DU (for example, it can be carried in the same F1AP message or carried in different F1AP messages respectively) message), the IAB node 1 first caches the RRC message of the IAB node 2 and the RRC message of the IAB node 3, and the IAB node 1 can specifically cache the IAB node 2 according to the indication information in the F1AP message carrying the RRC message of the IAB node 2/3 /3 RRC messages. After satisfying the first condition, IAB node 1 sends the RRC message of IAB node 2 to IAB node 2, and sends the RRC message of IAB node 3 to IAB node 3. After IAB node 2 receives its own RRC message, it The configuration information in the message initiates transport network layer migration, and the IAB node 3 initiates transport network layer migration according to the configuration information in the RRC message after receiving its own RRC message.

Similarly, the IAB host node-CU first carries the RRC message of the IAB node 4 in the F1AP message sent to the IAB node 2-DU, and/or carried in the F1AP message sent to the IAB node 3-DU. The IAB node 2 and/or the IAB node 3 buffer the RRC message of the IAB node 4 first. After the first condition is satisfied, the IAB node 2 and/or the IAB node 3 sends the RRC message of the IAB node 4 to the IAB node 4 again. After receiving its own RRC message, the IAB node 4 initiates transport network layer migration according to the configuration information in the RRC message.

Implementation method 2: The IAB master node-CU encapsulates the configuration information required for the transfer network layer migration of the subordinate nodes of the migrating IAB node into an RRC message, and sends the RRC messages of these subordinate nodes to each subordinate node from the source transmission path in advance . After the subordinate node receives its own RRC message, it does not take effect of the RRC message first, but after receiving the indication information sent by the parent node of the subordinate node to indicate that the cached RRC message is valid, and then according to the cached RRC message The configuration information in initiates transport network layer migration. Wherein, the parent node of the subordinate node sends the indication information to the subordinate node when it is determined that the first condition is satisfied.

Taking FIG. 5 as an example, the migrated IAB node is IAB node 1, and the subordinate nodes of IAB node 1 include IAB node 2, IAB node 3, and IAB node 4. The IAB host node-CU first carries the RRC message of the IAB node 2 in the F1AP message sent to the IAB node 1-DU, and the IAB node 1 sends the RRC message of the IAB node 2 carried in the F1AP message to the IAB node 2, and the IAB Node 2 first caches the RRC message but does not take effect of the configuration information in the RRC message. After receiving the instruction information sent by IAB node 1, IAB node 2 initiates transport network layer migration according to the configuration information in the cached RRC message. Similarly, the IAB host node-CU first carries the RRC message of the IAB node 3 in the F1AP message sent to the IAB node 1-DU, and the IAB node 1 sends the RRC message of the IAB node 3 carried in the F1AP message to the IAB node 3. IAB node 3 caches the RRC message first but does not take effect of the configuration information in the RRC message. After receiving the instruction information sent by IAB node 1, IAB node 3 initiates the transmission network layer according to the configuration information in the cached RRC message. migrate. Similarly, the IAB host node-CU first carries the RRC message of the IAB node 4 in the F1AP message sent to the IAB node 2-DU or the IAB node 3-DU, and the IAB node 2 or the IAB node 3 carries the RRC message in the F1AP message The RRC message of IAB node 4 is sent to IAB node 4, and IAB node 4 caches the RRC message first. After receiving the instruction information sent by IAB node 2 or IAB node 3, IAB node 4 initiates according to the configuration information in the cached RRC message. Transport network layer migration.

The above implementation method 1 and implementation method 2 are applicable not only to the topology update scenario within a single IAB network host, but also to the topology update scenario across IAB network hosts.

Regardless of whether the migration of the transmission network layer of the IAB node is realized through the above-mentioned implementation method 1 or the transmission network layer migration of the IAB node is realized through the above-mentioned realization method 2, the same problem is faced: how should the above-mentioned first condition be set? That is, when will the subordinate nodes of the migrating IAB node be triggered to perform transport network layer migration?

If the first condition is set unreasonably, it may cause the subordinate nodes of the migrating IAB node to perform the migration of the transport network layer too early, for example, before the migrating IAB node is connected to the target parent node of the migrating IAB node, migrating the IAB node The subordinate nodes of the IAB node start to try to perform the migration of the transport network layer, which will cause the subordinate nodes of the migrating IAB node to fail to perform the migration of the transport network layer.

If the first condition is set unreasonably, it may also cause the subordinate nodes of the migrating IAB node to perform the migration of the transport network layer too late, for example, when the migrating IAB node has connected to the target parent node of the migrating IAB node, and the migrating IAB node After the migration of the transport network layer has been completed, the subordinate nodes of the migrated IAB node perform the transport network layer migration in sequence, which will cause the waiting time for the transport network layer migration of these subordinate nodes to be too long. Especially when the relocated IAB node has multiple levels of subordinate nodes, the time between the completion of the transfer network layer migration of the relocated IAB node and the completion of the transfer of the transfer network layer by the subordinate nodes of the relocated IAB node is very long. The interruption of the UE) service to the subordinate node serving cell has a great impact.

From the above analysis, it can be seen that the selection of the timing for the subordinate nodes of the migrating IAB node to perform the migration of the transmission network layer is very important, so how to reasonably set the first condition, so as to instruct the subordinate nodes of the migrating IAB node to perform transmission at an appropriate time Network layer migration, to be resolved.

In order to instruct the subordinate nodes of the migrating IAB node to perform transport network layer migration at an appropriate time, the embodiment of the present application provides a communication method, which corresponds to the above-mentioned implementation method 1. This method provides the above-mentioned implementation method 1. Migrating the IAB node A first condition that needs to be met when sending an RRC message to a child node of the migrating IAB node.

This method is applicable not only to the topology update scenario within the IAB network host, but also to the topology update scenario across IAB network hosts.

With reference to Fig. 7 (a), this method comprises the following steps:

Step 701a, the first IAB node determines that the first condition is satisfied.

The first IAB node here refers to the migration IAB node, such as IAB node 1 in FIG. 5 or FIG. 6 .

This first condition includes:

Condition 1): The first IAB node receives the first RRC message from the IAB host CU.

Condition 2): The first IAB node switches from the source parent node of the first IAB node to the target parent node of the first IAB node according to the first RRC message.

Both condition 1) and condition 2) above need to be met.

Wherein, the first RRC message includes first configuration information, and the first configuration information is used for transport network layer migration between the first IAB node and the IAB host CU. The first RRC message may also be referred to as an RRC message of the first IAB node. Taking Fig. 5 or Fig. 6 as an example, when IAB node 1 receives the RRC message of IAB node 1, and IAB node 1 switches from the source parent node (i.e. IAB node 5) to successfully accessing to target parent node (that is, IAB node 6), then IAB node 1 determines that the first condition is met.

Wherein, the source parent node and the target parent node of the first IAB node are connected to different IAB host nodes-DU, and the first IAB node is connected to the same IAB host node-CU through the different IAB host node-DU before and after switching . Referring to the topology update scenario within the IAB network host shown in Figure 5 or the topology update scenario between IAB network hosts shown in Figure 6, the migrated IAB node is IAB node 1, and the source parent node of IAB node 1 before switching is IAB node 5. And IAB node 5 is connected to IAB host node-DU 1, the target parent node of IAB node 1 after switching is IAB node 6, and IAB node 6 is connected to IAB host node-DU2, and IAB host node-DU 1 is connected to IAB host node- DU 2 is a different IAB host node - DU. The IAB node 1 is connected to the IAB host node-CU through the IAB host node-DU1 before the handover, and the IAB node 1 is also connected to the IAB host node-CU through the IAB host node-DU2 after the handover. Among them, in the scenario in Figure 5, the IAB host node-DU 1 and the IAB host node-DU 2 connected to the IAB node 1 before and after the handover are managed by the same IAB host node-CU, while in the scenario in Figure 6, the IAB node 1 The IAB host node-DU 1 and the IAB host node-DU 2 connected before and after the handover are managed by different IAB host nodes-CU.

Step 702a, when the first condition is satisfied, the first IAB node sends a second RRC message to the second IAB node. Correspondingly, the second IAB node receives the second RRC message.

The second IAB node is a child node of the first IAB node. Taking FIG. 5 or FIG. 6 as an example, the first IAB node is IAB node 1, and the second IAB node is IAB node 2 or IAB node 3.

The second RRC message includes second configuration information, and the second configuration information is used for transport network layer migration between the second IAB node and the IAB host CU. The second RRC message may also be referred to as an RRC message of the second IAB node.

After the second IAB node receives the second RRC message, it may start to perform transport network layer migration. Taking FIG. 5 or FIG. 6 as an example, after the IAB node 2 receives the RRC message of the IAB node 2 from the IAB node 1, it may start to execute the transport network layer migration according to the RRC message of the IAB node 2. As an implementation method, after receiving the second RRC message, the second IAB node can start to perform transport network layer migration, which specifically includes: after the MT part of the second IAB node receives the second RRC message, according to the second RRC The second configuration information in the message performs reconfiguration, and then the MT part of the second IAB node sends an RRC reconfiguration complete (RRCReconfigurationComplete) message to the IAB host node-CU, and if the second RRC message carries a Migrate related configuration information, then the second IAB node performs transport network layer migration. Here, the second IAB node performs transport network layer migration as an example for illustration. For other nodes that need to perform transport network layer migration, they can also perform transport network layer migration according to this method. A unified description is given here, and details will not be described later.

According to the above scheme, after the first IAB node receives the first RRC message from the IAB host CU and the first IAB node switches from the source parent node of the first IAB node to the target parent node of the first IAB node according to the first RRC message , and then send a second RRC message to the second IAB node to trigger the second IAB node to perform transport network layer migration according to the second RRC message, avoiding the successful switching of the second IAB node to access the first IAB node at the first IAB node The target parent node of the node starts to perform the transport network layer migration before, so it can avoid the migration failure caused by the premature execution of the transport network layer migration of the second IAB node, thereby reducing the service delay impact on the UE served by the IAB node, and can Improve communication efficiency.

As an implementation method, on the basis that the above-mentioned first condition includes the above-mentioned condition 1) and the above-mentioned condition 2), the above-mentioned first condition also includes the following condition 3):

Condition 3): The first IAB node does not receive the first information from the IAB host node-CU.

Wherein, the first IAB node does not receive the first information from the IAB host node-CU, which may also be understood as before the first IAB node receives the first information from the IAB host node-CU.

The first information is used for data transmission after the handover of the first IAB node, where the data transmission may be data transmission on the user plane, or signaling transmission on the control plane. The first information may also be referred to as BAP routing configuration information on the target path, or as updated BAP routing configuration.

The first information includes one or more of a BAP route mapping configuration, a backhaul radio link control channel (BH RLC CH) mapping configuration, or a BAP route identification configuration.

Wherein, the BAP routing mapping configuration includes an updated routing mapping table to be used by the BAP layer of the first IAB node based on the new network topology after the first IAB node performs the handover, and the updated routing mapping table is used for the first IAB After the node is switched, routing is performed on the uplink data packet or the downlink data packet at the BAP layer. In the updated route mapping table, one or more entries are included, wherein each entry contains a BAP routing ID (BAP routing ID), and the identification of the next hop node corresponding to the BAP routing ID (for example BAP address of the next hop node).

The BH RLC CH mapping configuration includes the updated BH RLC CH mapping relationship to be used by the BAP layer of the first IAB node based on the new network topology after the first IAB node performs the handover, and the updated BH RLC CH mapping relationship is used for After the first IAB node switches, perform quality of service (QoS) mapping on the uplink data packet or downlink data packet at the BAP layer, that is, select an appropriate BH RLC CH for the uplink data packet or downlink data packet to be sent. As an implementation method, the updated BH RLC CH mapping relationship may include any one or more of the following: the identifier of each GTP-U tunnel of the F1 interface maintained by the first IAB node in uplink data transmission and The identification of the BH RLC CH of the corresponding egress link; the type information of each non-F1-U service type of the first IAB node in the uplink data transmission (specifically, it can be the F1-C interface message related to the UE, not related to the UE F1-C interface message, non-F1 type message, BAP control PDU, etc.) and the identification of the BH RLC CH of the corresponding egress link; during uplink or downlink data transmission, the BH RLC of the ingress link of the first IAB node The ID of the CH and the ID of the BH RLC CH corresponding to the egress link.

BAP routing identification configuration, including after the first IAB node performs switching, based on the new network topology, one or more BAP routing IDs to be used by the BAP layer of the first IAB node, and the one or more BAP routing IDs are the first A BAP routing ID that an IAB node will add at the BAP layer to the uplink data packet submitted by the upper protocol layer of the BAP layer (for example, the IP layer of the DU of the first IAB node). As an implementation method, the BAP routing identifier configuration may include any one or more of the following: the identifier of each GTP-Utunnel of the F1 interface maintained by the first IAB node in uplink data transmission and the corresponding BAP routing ID; type information of each non-F1-U service type of the first IAB node in uplink data transmission (specifically, it can be an F1-C interface message related to UE, an F1-C interface message irrelevant to UE, non-F1 type message, BAP control PDU, etc.) and the corresponding BAP routing ID.

In this application, the identification of the BH RLC CH of the egress link of the IAB node may be jointly identified by the BAP address of the next-hop node of the IAB node corresponding to the egress link and the BHRLC CH ID on the egress link. The identifier of the BH RLC CH of the ingress link of the IAB node may be jointly identified by the BAPaddress of the previous hop node of the IAB node corresponding to the ingress link and the BHRLC CH ID on the ingress link. The identifier of each GTP-Utunnel of the F1 interface maintained by the IAB node can be jointly identified by the upstream tunnel endpoint identifier (tunnel endpoint identifier, TEID) of the GTP-U tunnel and the upstream destination IP address, wherein the TEID is identified with the IAB node The IAB host node-CU that establishes the F1-U interface between them (in the scenario where the IAB host node-CU is separated from CP-UP, specifically, it can be the IAB host node-CU-UP), the destination IP address of the uplink is The IP address of the IAB host node-CU (or IAB host node-CU-UP).

Wherein, if the first IAB node receives the first information from the IAB host node-CU, it indicates that the IAB host node-CU has completed the routing update to the IAB network after the first IAB node switches, and obtains the above-mentioned first information. Therefore, through this condition 3), it is limited that the first IAB node sends the second RRC message to the second IAB node before receiving the first information from the IAB host node-CU, so that the second IAB node can start to execute the transport network layer as soon as possible Migration can prevent the second IAB node from executing the migration of the transport network layer too late and cause the service interruption delay of the UE to be too long, thereby reducing the impact on the service delay of the UE served by the IAB node, and improving communication efficiency.

Generally, the first IAB node receives the F1AP message carrying the first information from the IAB host-CU after the migration of the transport network layer of the first IAB node is completed. Therefore, before the migration of the transport network layer of the first IAB node is completed, the first IAB node will generally not receive the first information.

As an implementation method, on the basis that the above-mentioned first condition includes the above-mentioned condition 1) and the above-mentioned condition 2), or on the basis that the above-mentioned first condition includes the above-mentioned condition 1), condition 2) and condition 3), the above-mentioned first The conditions also include the following conditions 4):

Condition 4): The first IAB node has not completed the transport network layer migration between the first IAB node and the IAB host node-CU according to the first configuration information.

Wherein, the first IAB node does not complete the transport network layer migration between the first IAB node and the IAB host node-CU according to the first configuration information, which can also be understood as the first IAB node completes the first IAB node according to the first configuration information Before the migration of the transport network layer with the IAB host node-CU.

Through this condition 4), it is avoided that the first IAB node starts to send the second RRC message to the second IAB node after completing the transfer of the transport network layer, so it can be avoided that the second IAB node causes the UE to perform the transfer of the transport network layer too late. The service interruption delay is too long, thereby reducing the service delay impact on the UE served by the IAB contact, and improving communication efficiency.

In order to instruct the subordinate nodes of the migrating IAB node to perform transport network layer migration at an appropriate time, the embodiment of the present application provides a communication method, which corresponds to the above-mentioned implementation method 1. This method provides the above-mentioned implementation method 1. Migrating the IAB node The first condition that needs to be met when the subordinate node of the subordinate node sends the RRC message to the child node of the subordinate node.

This method is applicable not only to the topology update scenario within the IAB network host, but also to the topology update scenario across IAB network hosts.

Referring to Figure 7(b), the method comprises the following steps:

In step 701b, the first IAB node determines that the first condition is satisfied.

The first IAB node here refers to a certain subordinate node of the migrated IAB node, for example, it may be IAB node 2 or IAB node 3 in FIG. 5 or FIG. 6 .

This first condition includes:

Condition 1): The first IAB node receives the first RRC message from the second IAB node.

Wherein, the second IAB node is the parent node of the first IAB node. For example, referring to FIG. 5 or FIG. 6, the first IAB node is IAB node 2, and the second IAB node is IAB node 1, or, the first IAB node is IAB node 3, and the second IAB node is IAB node 1.

The first RRC message includes first configuration information, and the first configuration information is used for transport network layer migration between the first IAB node and the IAB host node-CU. After receiving the first RRC message, the first IAB node may start to perform transport network layer migration.

Wherein, the first IAB node is connected to the IAB host node-CU through different IAB host node-DUs before and after the handover, for details, reference may be made to the description of the embodiment in FIG. 7( a ).

Step 702b, when the first condition is satisfied, the first IAB node sends a second RRC message to the third IAB node. Correspondingly, the second IAB node receives the second RRC message.

The third IAB node is a child node of the first IAB node. For example, the first IAB node is IAB node 2, the second IAB node is IAB node 1, and the third IAB node is IAB node 4.

The second RRC message includes second configuration information, and the second configuration information is used for transport network layer migration between the third IAB node and the IAB host node-CU.

After receiving the second RRC message, the third IAB node may start to perform transport network layer migration.

According to the above scheme, after the first IAB node receives the first RRC message from the second IAB node, it can start to perform the migration of the transport network layer on the one hand, and on the other hand immediately send the second RRC message to the child nodes of the first IAB node , so as to trigger the child nodes of the first IAB node to start performing transport network layer migration as early as possible, which can avoid the UE’s service interruption delay being too long due to the child nodes of the first IAB node performing transport network layer migration too late, thereby reducing The impact on the service delay of the UE served by the IAB contact can improve communication efficiency.

As an implementation method, on the basis that the above-mentioned first condition includes the above-mentioned condition 1), the above-mentioned first condition also includes the following condition 2):

Condition 2): The first IAB node does not receive the first information from the second IAB node.

The first information is used for data transmission after the handover of the first IAB node, where the data transmission may be data transmission on the user plane, or signaling transmission on the control plane.

The first information includes one or more of BAP route mapping configuration, BH RLC CH mapping configuration, or BAP route identification configuration. For the meaning of BAP route mapping configuration, BH RLC CH mapping configuration or BAP route identification configuration, please refer to the foregoing description.

Generally, the first IAB node receives the F1AP message carrying the first information from the IAB host-CU after the migration of the transport network layer of the first IAB node is completed. Therefore, before the migration of the transport network layer of the first IAB node is completed, the first IAB node will generally not receive the first information.

Wherein, if the first IAB node receives the first information from the second IAB node, it indicates that the IAB host node-CU has completed the routing update of the IAB network and obtained the above-mentioned first information. Therefore, through this condition 2), it is limited that the first IAB node sends the second RRC message to the third IAB node before receiving the first information from the second IAB node, so that the third IAB node can start to perform transport network layer migration as early as possible It can prevent the third IAB node from executing the migration of the transport network layer too late and cause the service interruption delay of the UE to be too long, thereby reducing the impact on the service delay of the UE served by the IAB node, and improving communication efficiency.

As an implementation method, on the basis that the above-mentioned first condition includes the above-mentioned condition 1) and the above-mentioned condition 2), or on the basis that the above-mentioned first condition includes the above-mentioned condition 1), condition 2) and condition 3), the above-mentioned first The conditions also include the following conditions 4):

Condition 3): The first IAB node has not completed the transport network layer migration between the first IAB node and the IAB host node-CU according to the first configuration information.

Wherein, the first IAB node does not complete the transport network layer migration between the first IAB node and the IAB host node-CU according to the first configuration information, which can also be understood as the first IAB node completes the first IAB node according to the first configuration information Before the migration of the transport network layer with the IAB host node-CU.

Through this condition 3), it is avoided that the first IAB node starts to send the second RRC message to the third IAB node after completing the migration of the transport network layer, so it can be avoided that the third IAB node causes the UE to perform the migration of the transport network layer too late. The service interruption delay is too long, thereby reducing the service delay impact on the UE served by the IAB contact, and improving communication efficiency.

In order to instruct the subordinate nodes of the migrating IAB node to perform transport network layer migration at an appropriate time, the embodiment of the present application provides a communication method, which corresponds to the second implementation method above. A first condition that needs to be met when sending an RRC message to a child node of the migrating IAB node.

This method is applicable not only to the topology update scenario within the IAB network host, but also to the topology update scenario across IAB network hosts.

Referring to Figure 8(a), the method includes the following steps:

Step 801a is the same as the above step 701a.

Step 802a, after the first condition is satisfied, the first IAB node sends indication information to the second IAB node. Correspondingly, the second IAB node receives the indication information.

The second IAB node is a child node of the first IAB node. Taking FIG. 5 or FIG. 6 as an example, the first IAB node is IAB node 1, and the second IAB node is IAB node 2 or IAB node 3.

The indication information is used to trigger a second RRC message in the second IAB node to take effect, and the second RRC message includes second configuration information, and the second configuration information is used for transport network layer migration of the second IAB node. The second RRC message may also be referred to as an RRC message of the second IAB node.

Wherein, before the above step 801a, the second IAB node may receive the second RRC message from the IAB host node-CU and store it locally. Then, after receiving the above indication information from the first IAB node, the second IAB node validates the second RRC message according to the indication information. That is, after the second IAB node receives the indication information, it can start to execute the migration of the transport network layer. Taking FIG. 5 or FIG. 6 as an example, after IAB node 2 receives the indication information for triggering the RRC message of IAB node 2 to take effect from IAB node 1, it starts to perform transport network layer migration according to the RRC message of IAB node 2.

For the beneficial effects of the above solutions, reference may be made to the beneficial effects of the embodiment in FIG. 7( a ), which will not be repeated here.

As an implementation method, on the basis of the first condition including the above-mentioned condition 1) and condition 2), it can also include the condition 3) and/or condition 4) in the embodiment of Figure 7 (a), and the specific description can refer to The description of the embodiment in Fig. 7(a) will not be repeated here.

In order to instruct the subordinate nodes of the migrating IAB node to perform transport network layer migration at an appropriate time, the embodiment of the present application provides a communication method, which corresponds to the second implementation method above. The first condition that needs to be met when the subordinate node of the subordinate node sends the RRC message to the child node of the subordinate node.

This method is applicable not only to the topology update scenario within the IAB network host, but also to the topology update scenario across IAB network hosts.

Referring to Figure 8(b), the method includes the following steps:

Step 801b, the first IAB node determines that the first condition is met.

The first IAB node here refers to a certain subordinate node of the migrated IAB node, for example, it may be IAB node 2 or IAB node 3 in FIG. 5 or FIG. 6 .

This first condition includes:

Condition 1): The first IAB node receives the first indication information from the second IAB node.

The first indication information is used to trigger the first RRC message in the first IAB node to take effect.

Wherein, the second IAB node is the parent node of the first IAB node. For example, referring to FIG. 5 or FIG. 6, the first IAB node is IAB node 2, and the second IAB node is IAB node 1, or, the first IAB node is IAB node 3, and the second IAB node is IAB node 1.

For the meaning of the first RRC message, reference may be made to the description of the embodiment in FIG. 7( b ).

Step 802b, when the first condition is satisfied, the first IAB node sends second indication information to the third IAB node. Correspondingly, the third IAB node receives the second indication information.

The third IAB node is a child node of the first IAB node. For example, the first IAB node is IAB node 2, the second IAB node is IAB node 1, and the third IAB node is IAB node 4.

The second indication information is used to trigger the second RRC message in the third IAB node to take effect.

For the meaning of the second RRC message, reference may be made to the description of the embodiment in FIG. 7( b ).

After receiving the second indication information, the third IAB node starts to perform transport network layer migration according to the stored second RRC message.

According to the above scheme, after the first IAB node receives the first instruction information from the second IAB node, it can start to perform the migration of the transport network layer on the one hand, and on the other hand immediately send the second instruction information to the child nodes of the first IAB node , so as to trigger the child nodes of the first IAB node to start performing transport network layer migration as early as possible, which can avoid the UE’s service interruption delay being too long due to the child nodes of the first IAB node performing transport network layer migration too late, thereby reducing The impact on the service delay of the UE served by the IAB contact can improve communication efficiency.

As an implementation method, on the basis that the first condition includes the above-mentioned condition 1), it may also include the condition 2) and/or condition 3) in the embodiment of Figure 7(b), and the specific description can refer to Figure 7(b) ) of the description of the embodiment, no longer repeat.

It should be noted that, in the above-mentioned embodiments of FIG. 7(a), FIG. 7(b), FIG. 8(a) and FIG. It is not necessary to execute. When this action is not performed, it can be understood that after the first condition is met, the first IAB node can perform subsequent operations, such as performing the above step 702a, step 702b, step 802a or step 802b.

It should be noted that the above-mentioned embodiments of FIG. 7( a ), FIG. 7( b ), FIG. 8( a ), and FIG. 8( b ) can be implemented individually or in combination. Such as above-mentioned Fig. 7 (a) and the embodiment of Fig. 7 (b) are implemented in combination, again such as above-mentioned Fig. 8 (a) and the embodiment of Fig. 8 (b) are implemented in combination, again such as above-mentioned Fig. 7 (a) and The embodiment of FIG. 8(b) is implemented in combination, and another example is the embodiment of the above-mentioned FIG. 8(a) and FIG. 7(b).

In the scenario where the migration of the IAB node and the subordinate nodes of the migrated IAB node need to complete the transport layer migration due to the switchover of the IAB node, how to migrate the IAB node and the subordinate nodes of the migrated IAB node before the transport layer migration needs to be completed after the switchover of the IAB node is completed. The source path (that is, the old transmission path) is unavailable, and the transport layer migration on the target path (that is, the new transmission path) has not been completed, so the target path is also temporarily unavailable. In this case, how to transmit the uplink data packet correctly or Downlink data packets also need to be resolved.

In order to solve this problem, the embodiment of the present application also provides a corresponding data transmission method. The following data transmission method can be compared with the above-mentioned embodiment of FIG. 7(a), FIG. 7(b), FIG. 8(a) or FIG. 8(b) One or more of the embodiments may be combined with the embodiments, or may be implemented separately.

The following data transmission methods can be applied to the topology update scenario within the host of the IAB network or the topology update scenario of the cross-host of the IAB network. The migrating IAB node is switched from the source parent node to the target parent node. After the migrating IAB node is switched to the target parent node, the migration of the transport network layer between the migrating IAB node and the subordinate IAB node of the migrating IAB node and the IAB host node-CU is completed. Previously, each IAB node on the target path could neither continue to use the source path for data transmission nor directly use the target path for data transmission. At this time, how to transmit data packets on the target path can use the following provided by the embodiment of this application data transfer method.

For example, referring to FIG. 5, the migration IAB node is IAB node 1. Before IAB node 1 switches from accessing IAB node 5 to accessing IAB node 6, the source path includes some or all of the following nodes: UE, IAB node 4. IAB node 3, IAB node 1, IAB node 5, IAB host-DU 1, IAB host node-CU. After IAB node 1 switches from accessing IAB node 5 to accessing IAB node 6, the target path includes some or all of the following nodes: UEIAB node 4, IAB node 3, IAB node 1, IAB node 6, and IAB host -DU 2, IAB host node -CU. After IAB node 1 is switched to access IAB node 6, the IAB node and the subordinate IAB nodes on the target path of the migrated IAB node, such as IIAB node 3 and IAB node 4, need to complete the communication with the IAB host node-CU Transport network layer migration. Therefore, before the migration of the transport network layer between IAB node 1, IAB node 3, and IAB node 4 and the IAB host node-CU is completed, neither the source path nor the target path can be used normally. The following data transfer methods.

The uplink data packet or downlink data packet described in the following embodiments may be a service data packet, or may be a data packet for transport network layer migration. When the upstream data packet or the downstream data packet is a data packet transferred by the transmission network layer, the upstream data packet or the downstream data packet can be various data blocks (CHUNK) of the SCTP layer, such as SCTP INITCHUNK, or IPsec security Messages related to the negotiation process (such as IKEv2-related messages), or F1AP messages, such as F1 SETUP REQUEST messages and GNB-DU CONFIGURATION UPDATE messages involved in the connection establishment process.

The data transmission methods of the migrated IAB node and the subordinate nodes of the migrated IAB node in different scenarios will be described below.

1. Data transmission method for migrating IAB nodes

Hereinafter, the first IAB node is used to indicate the migration IAB node, and the first IAB node is, for example, IAB node 1 in FIG. 5 or FIG. 6 . Moreover, before the first IAB node receives the uplink data packet or the downlink data packet, it has received the first RRC message from the IAB host node-CU, and the first RRC message includes the first configuration information.

For uplink transmission, the first configuration information includes a first BAP routing identifier, and the first BAP routing identifier is used for the first IAB node to perform uplink data transmission on the target path. Wherein, the first BAP routing identifier here may also be called a default BAP routing identifier. Optionally, the first configuration information may also include the identifier of the BH RLC CH between the first IAB node and the next hop node for uplink transmission of the first IAB node, and the identifier of the BH RLC CH is used to identify the first A BH RLC CH between an IAB node and a next-hop node for uplink transmission of the first IAB node, wherein the next-hop node of the first IAB node may be a target parent node of the first IAB node. Wherein, the identifier of the BH RLC CH here may also be referred to as the identifier of the default BHRLC CH. Wherein, "the BH RLCCH between the first IAB node and the first IAB node's next-hop node for uplink transmission" may also be referred to as "the BH RLC CH between the first IAB node and the parent node of the first IAB node" .

For downlink transmission, the first configuration information may also include an identifier of a BHRLC CH between the first IAB node and its child nodes, and the BH RLC CH is a default BH RLC CH between the first IAB node and its child nodes. When the first IAB node needs to send a downlink BAP protocol data unit (protocol data unit, PDU) to its child node but based on the current configuration, no mapping relationship can be found that matches the BAP PDU, the first IAB node can send The BAP PDU is mapped to the BH RLC CH and sent to the subnode. In a possible implementation manner, the identifier of the BH RLC CH may be jointly determined by an identifier of a child node of the first IAB node (for example, a BAP address of the child node) and a BH RLC CH ID of the BH RLC CH. Wherein, "the BH RLC CH between the first IAB node and the child node of the first IAB node" may also be referred to as "the BH RLC CH between the first IAB node and the next-hop node for downlink transmission of the first IAB node" ".

In another possible implementation, the identity of the BH RLC CH between the first IAB node and its child nodes is not configured through the first configuration information, but is sent by the IAB host node-CU through the F1AP message For the first IAB node, the F1AP message may be sent to the first IAB node before the IAB host node-CU sends the first RRC message to the first IAB node, or may be sent to the first IAB node according to the first RRC message It is sent by the IAB host node-CU to the first IAB node after the connection is switched to the target parent node. For example, in the F1AP message, the configuration information of one or more BH RLC CHs between the first IAB node and one or more subnodes of the first IAB node is carried, and the configuration information includes the configuration information of the first IAB node and the first IAB node. The identification of the BH RLC CH between the child nodes of the node. Optionally, indication information may also be included in the configuration information, where the indication information is used to indicate the default BH RLC CH in the configuration information. For example, the first IAB node has two child nodes, which are IAB node a and IAB node b, and there are two BH RLC CHs between the first IAB node and IAB node a, which are BH RLC CH a, BH RLC CH b, There are three BH RLC CHs between the first IAB node and IAB node b, which are BHRLC CH c, BH RLC CH d, and BH RLC CH e. The F1AP message sent by the IAB host node-CU to the first IAB node contains configuration information 1 and configuration information 2, and the configuration information 1 includes the identification of the BH RLCCH a between the first IAB node and the IAB node a and the BH RLC The identity of CH b, and indication information for indicating that the BH RLC CH b indicated by the identity of the BH RLC CH b is the default BH RLC CH between the first IAB node and IAB node a, the configuration information 2 Contains the identity of BH RLC CH c between the first IAB node and IAB node b, the identity of BH RLC CH d and the identity of BH RLC CH e, and also includes indication information, which is used to indicate the identity of the BH RLC CH c The indicated BH RLC CH c is the default BH RLC CH between the first IAB node and IAB node b. In a specific implementation, the configuration information 1 and the configuration information 2 can be respectively carried in different F1AP messages and sent to the first IAB node, or the configuration information 1 and the configuration information 2 can also be combined into one configuration information, the configuration information It may be carried in an F1AP message and sent to the first IAB node.

Optionally, the first configuration information also includes a new IP address allocated for the first IAB node, and the new IP address can be used for data or signaling transmission of the first IAB node on the new transmission path, for example, by using Migrate at the transport network layer of the first IAB node.

The following describes the data transmission methods in the topology update scenario of migrating IAB nodes within the IAB network host and the topology update scenario of the IAB network across hosts.

1. The data transmission method performed by migrating IAB nodes in the topology update scenario in the IAB network host

Migrating IAB nodes In the topology update scenario of the IAB network host, the source parent node and target parent node of the migrating IAB node are connected to different IAB host nodes-DU, and the different IAB host node-DUs are respectively connected to the IAB host node The F1 interface is established between -CUs, or it is understood that the different IAB host nodes-DUs belong to the same IAB host node-CU, or it is understood that the different IAB host nodes-DUs are managed by the same IAB host node-CU. Taking Figure 5 as an example, the source parent node of IAB node 1 is connected to IAB host node-DU 1, the target parent node of IAB node 1 is connected to IAB host node-DU2, IAB host node-DU 1 and IAB host node-DU 2 Belong to the same IAB host node-CU.

The following is divided into the uplink direction and the downlink direction, respectively introducing the data transmission method performed by the migrated IAB node in the topology update scenario in the IAB network host.

1) Uplink direction

Referring to FIG. 9 , it is a schematic flow chart of a data transmission method provided by an embodiment of the present application. The method introduces a processing method after a migrated IAB node receives an uplink data packet.

The method includes the following steps:

Step 901, the first IAB node receives an uplink data packet.

Specifically, the first IAB node receives an uplink data packet from a child node of the first IAB node, and the uplink data packet may be generated by a subordinate node of the first IAB node, such as IAB node 2, IAB node 3 or The uplink data packet is generated by the IAB node 4, or the uplink data packet may also be generated by the UE, and the present application does not limit the generation method of the uplink data packet.

The uplink data packet contains a second BAP routing identifier, which is added by the IAB node that generates the uplink data packet to the uplink data packet according to the configuration information received from the IAB host node-CU, the second BAP routing identifier The BAP routing identifier is used for the IAB node to perform data transmission on the target path.

Step 902, when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, the first IAB node sends an uplink data packet according to the first BAP routing identifier.

According to the above scheme, after the migration IAB node (ie, the first IAB node) is switched to the target parent node, and before the migration of the transport network layer between the migration IAB node (ie, the first IAB node) and the IAB host node-CU is completed, After the first IAB node receives the uplink data packet, if the BAP address in the uplink data packet is the same as the BAP address in the first BAP routing identifier, then the first IAB node can use the first BAP routing identifier to process the uplink data packet routing. In this way, it can be ensured that the received uplink data packets are sent successfully and packet loss is avoided. In addition, it is also possible to transmit the uplink data packet as early as possible, reducing the service interruption delay of the UE.

As an implementation method, the above step 902 is specifically: when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, and the first IAB node has not received the first BAP address from the IAB host node-CU information, the first IAB node sends the uplink data packet according to the first BAP routing identifier. Wherein, the first information is used for data transmission after switching of the first IAB node, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration. For the specific meanings of BAP route mapping configuration, BH RLC CH mapping configuration and BAP route identification configuration, please refer to the foregoing description. According to this scheme, before the BAP routing configuration information is received on the target path, the routing of the above-mentioned data packets cannot be performed according to the BAP routing configuration information on the target path, but the above-mentioned method of the application can be used, and the first IAB node uses its own The received uplink data packet is routed with the first BAP routing identifier, so as to ensure that the received uplink data packet is successfully sent and avoid packet loss.

As an implementation method, the first IAB node sends the uplink data packet according to the first BAP routing identifier, which may be specifically: the first IAB node determines the next hop node of the first IAB node corresponding to the first BAP routing identifier, and then the first The IAB node sends the uplink data packet to the next-hop node. Wherein, the next hop node of the first IAB node corresponding to the first BAP routing identifier may be a default parent node of the first IAB node, for example, the default parent node may be a target parent node of the first IAB node. Or the above-mentioned first configuration information also includes the identifier of the next-hop node corresponding to the first BAP routing identifier, then the next-hop node of the first IAB node corresponding to the first BAP routing identifier is the identifier of the next-hop node the indicated node. Optionally, the first configuration information also includes the identifier of the BH RLC CH, and the identifier of the BH RLC CH can be used to indicate the default BH RLC CH between the first IAB node and its default parent node, so the first IAB node The uplink data packet may be sent to the next-hop node of the first IAB node on the BH RLC CH indicated by the identifier of the BH RLC CH.

Referring to FIG. 10 , it is a schematic flowchart of a data transmission method provided by an embodiment of the present application. The method introduces a sending method after a migrated IAB node generates an uplink data packet.

The method includes the following steps:

Step 1001, the first IAB node generates an uplink data packet.

The first IAB node here refers to the migration IAB node, such as IAB node 1 in FIG. 5 . And, before the first IAB node generates the uplink data packet, it has received the first RRC message from the IAB host node-CU, the first RRC message includes the first configuration information, and the first configuration information includes the first BAP routing identifier , the first BAP route identifier is used for the first IAB node to perform data transmission on the target path.

The generated uplink data packet includes the first BAP routing identifier.

Step 1002, the first IAB node determines the next hop node of the first IAB node corresponding to the first BAP routing identifier.

Wherein, the first IAB node determines the next-hop node of the first IAB node corresponding to the first BAP routing identifier, and reference may be made to the description in the embodiment of FIG. 9 , and details are not repeated here.

Step 1003, the first IAB node sends an uplink data packet to the next-hop node.

For sending the uplink data packet to the next-hop node by the first IAB node, reference may be made to the description in the embodiment of FIG. 9 , and details are not repeated here.

According to the above scheme, after the migrating IAB node is switched to the target parent node, and before the migration of the transport network layer between the migrating IAB node and the IAB host node-CU is completed, after the first IAB node generates an uplink data packet, it uses the first BAP The routing identifier routes the uplink data packet. In this way, it can be ensured that the received uplink data packets are sent successfully and packet loss is avoided. In addition, it is also possible to transmit the uplink data packet as early as possible, reducing the service interruption delay of the UE.

2) Downlink direction

Referring to FIG. 11 , it is a schematic flowchart of a data transmission method provided by the embodiment of the present application. The method introduces a processing method after a migrated IAB node receives a downlink data packet.

The method includes the following steps:

Step 1101, the first IAB node receives a downlink data packet, and the downlink data packet includes a third BAP routing identifier.

The downlink data packet is generated by an upstream node of the first IAB node, for example, after the IAB host node-DU2 in FIG. 5 adds a BAP layer header to the received downlink IP packet.

In this embodiment of the application, "the upstream node of the first IAB node" includes the parent node of the first IAB node and nodes above the parent node, or it can be understood as the IAB on the transmission path between the IAB host node and the first IAB node node. Specifically, the upstream nodes of the first IAB node include the parent node of the first IAB node, the grandparent node, the parent node of the grandparent node, the grandparent node of the grandparent node, and so on. Here is a unified description, and will not be repeated later.

The downlink data packet includes a third BAP route identifier, which is added to the downlink data packet by the IAB host node-DU node that generates the downlink data packet based on configuration information received from the IAB host node-CU Yes, the third BAP route identifier is used for downlink data transmission on the target path.

Step 1102, the first IAB node determines that the first RRC message has been received, and the first IAB node has not received the first information from the IAB host node-CU, then determine the first IAB node according to the BAP address in the third BAP routing identifier next hop node.

That is, when the rerouting trigger condition is met, the first IAB node performs rerouting according to the BAP address in the third BAP routing identifier, and the rerouting node is the determined next-hop node of the first IAB node. The rerouting trigger condition is: the first IAB node determines to receive the first RRC message, and the first IAB node does not receive the first information from the IAB host node-CU.

For the meaning of the first information here, refer to the foregoing description, and details are not repeated here.

Wherein, the first IAB node determines the next-hop node of the first IAB node according to the BAP address in the third BAP routing identifier, which may specifically be: the first IAB node searches for the same information as the third BAP node in the route mapping table configured for it. If the table entry matched by the BAP route identifier can be found, the next hop node indicated by the next hop node identifier in the table entry is selected. If can't find the table item that matches with the 3rd BAP routing identification, then search the table item that can match with the BAP address field in the 3rd BAP routing identification, then the next hop node identification indicated in the table item The one-hop node is determined as the next-hop node for sending downlink data packets. If based on the BAP address field in the third BAP routing identifier, the route mapping table is searched to obtain multiple matching entries, that is, the identifiers of multiple next-hop nodes are obtained, then the first IAB node can be in the multiple next-hop nodes. Choose one of the identifiers, or select the identifier of the next-hop node corresponding to the entry with the highest priority according to the priority of each matching entry.

Step 1103, the first IAB node sends a downlink data packet to the next-hop node.

According to the above scheme, after the migration IAB node is switched to the target parent node, and before the migration of the transmission network layer between the migration IAB node and the IAB host node-CU is completed, after the first IAB node receives the downlink data packet, when it is determined that the The rerouting trigger condition is to perform rerouting according to the BAP address in the third BAP routing identifier. In this way, it can be ensured that the received downlink data packets are sent successfully and packet loss is avoided. In addition, it is also possible to transmit the downlink data packet as early as possible, reducing the service interruption delay of the UE.

2. The data transmission method performed by migrating IAB nodes in the scenario of IAB network cross-host topology update

Migrating IAB nodes In the IAB network cross-host topology update scenario, the source parent node and target parent node of the migrating IAB node are connected to different IAB host nodes-DU, and the different IAB host nodes-DU are connected to different IAB host nodes. The F1 interface is established between the nodes-CU, or it is understood that the different IAB host node-DUs belong to different IAB host node-CUs, or it is understood that the different IAB host node-DUs are managed by different IAB host node-CUs . Wherein, the source parent node is connected to the source IAB host node-DU, the source IAB host node-DU belongs to the source IAB host node-CU, and the source IAB host node-DU and the source IAB host node-CU can be collectively referred to as the source IAB host node. The target parent node is connected to the target IAB host node-DU, the target IAB host node-DU belongs to the target IAB host node-CU, and the target IAB host node-DU and the target IAB host node-CU can be collectively referred to as the target IAB host node. Taking Figure 6 as an example, the source parent node of IAB node 1 is connected to IAB host node -DU 1, the target parent node of IAB node 1 is connected to IAB host node -DU 2, and IAB host node -DU 1 belongs to IAB host node - CU 1, IAB host node-DU 2 belongs to IAB host node-CU 2. The following is divided into the uplink direction and the downlink direction, respectively introducing the data transmission method performed by the migrating IAB node in the topology update scenario between IAB network hosts (that is, cross-IAB hosts).

1) Uplink direction

Referring to FIG. 12 , it is a schematic flowchart of a data transmission method provided by the embodiment of the present application, which describes the processing method after the migrating IAB node receives the uplink data packet.

The method includes the following steps:

Step 1201, the first IAB node receives an uplink data packet.

Specifically, the first IAB node receives an uplink data packet from a child node of the first IAB node, and the uplink data packet may be generated by a subordinate node of the first IAB node, such as IAB node 2, IAB node 3 or The uplink data packet is generated by the IAB node 4, or the uplink data packet may also be generated by the UE, and the present application does not limit the generation method of the uplink data packet.

The uplink data packet contains a second BAP routing identifier, which is added to the uplink data packet by the IAB node that generates the uplink data packet according to the configuration information received from the IAB host node-CU, the second BAP routing identifier Two BAP routing identifiers are used for the IAB node to perform data transmission on the target path.

Step 1202, the first IAB node replaces the second BAP routing identifier in the uplink data packet with the first BAP routing identifier.

As an implementation method, when the BAP address in the second BAP routing identifier is the same as the BAP address allocated by the source IAB host node-CU to the first IAB node, the first IAB node will use the second BAP routing identifier in the uplink data packet Replace it with the ID of the first BAP route. Wherein, the BAP address allocated by the source IAB host node-CU for the first IAB node may be sent to the first IAB node by the source IAB host node-CU through an RRC message before the MT part of the first IAB node is switched to the target parent node .

As another implementation method, when the BAP address in the second BAP routing identifier is the same as the BAP address allocated by the source IAB host node-CU to the target IAB host node DU, the first IAB node will send the second BAP address in the upstream data packet The routing identifier is replaced with the first BAP routing identifier. Wherein, the BAP address allocated by the source IAB host node-CU to the target IAB host node DU may be configured to the first IAB node by the source IAB host node-CU in advance through an F1AP message or an RRC message, or may be in the first IAB node After the MT part is handed over to the target parent node, the target IAB host node-CU sends the RRC message to the first IAB node.

Step 1203, the first IAB node sends the uplink data packet according to the first BAP routing identifier.

According to the above scheme, after the migrating IAB node is switched to the target parent node, and before the migration of the transmission network layer between the migrating IAB node and the IAB host node-CU is completed, after the first IAB node receives the uplink data packet, if the uplink The BAP address in the data packet is the same as the BAP address of the first IAB node, or the BAP address in the uplink data packet is the same as the BAP address allocated by the source IAB host node-CU for the target IAB host node-DU, indicating that the first IAB is required The node replaces the BAP routing identifier in the uplink data packet, and then the first IAB node uses the first BAP routing identifier of the first IAB node to route the uplink data packet. In this way, it can be ensured that the received uplink data packets are sent successfully and packet loss is avoided. In addition, it is also possible to transmit the uplink data packet as early as possible, reducing the service interruption delay of the UE.

As an implementation method, the above step 1202 may specifically be: when the BAP address in the second BAP routing identifier is the same as the BAP address of the first IAB node, and the first IAB node has not received the first IAB node-CU from the target IAB host node-CU information, the first IAB node sends the uplink data packet according to the first BAP routing identifier. Alternatively, the above step 1202 may specifically be: when the BAP address in the second BAP routing identifier is the same as the BAP address allocated by the source IAB host node-CU to the target IAB host node-DU, and the first IAB node has not received the same BAP address from the target IAB host node. - When the CU receives the first information, the first IAB node sends the uplink data packet according to the first BAP routing identifier. Wherein, the meaning of the first information may refer to the foregoing description. According to this scheme, before the BAP routing configuration information (i.e. the first information) is received on the target path, the routing of the above-mentioned data packets cannot be carried out according to the BAP routing configuration information on the target path, but the above-mentioned method of the present application can be used, by The first IAB node uses its own first BAP routing identifier to route the received uplink data packet, so as to ensure that the received uplink data packet is successfully sent and avoid packet loss.

As an implementation method, the first IAB node sends the uplink data packet according to the first BAP routing identifier, which may be specifically: the first IAB node determines the next hop node of the first IAB node corresponding to the first BAP routing identifier, and then the first The IAB node sends the uplink data packet to the next-hop node. Wherein, the next hop node of the first IAB node corresponding to the first BAP routing identifier may be the default parent node of the first IAB node. Or the above-mentioned first configuration information further includes the identifier of the next-hop node, then the next-hop node of the first IAB node corresponding to the first BAP routing identifier is the node indicated by the identifier of the next-hop node. Optionally, the first configuration information also includes the identifier of the BH RLC CH, and the identifier of the BH RLC CH can be used to indicate the default BH RLC CH between the first IAB node and its default parent node, so the first IAB node The uplink data packet may be sent to the next-hop node of the first IAB node on the BH RLC CH indicated by the identifier of the BHRLC CH.

2) Downlink direction

Referring to FIG. 13 , it is a schematic flowchart of a data transmission method provided by the embodiment of the present application. The method introduces a processing method after a migrated IAB node receives a downlink data packet.

The method includes the following steps:

Step 1301, the first IAB node receives a downlink data packet.

The downlink data packet is generated by an upstream node of the first IAB node, for example, after the IAB host node-DU2 in FIG. 6 adds a BAP layer header to the received downlink IP packet.

The downlink data packet contains a third BAP routing identifier, which is added to the downlink data packet by the IAB host node-DU that generates the downlink data packet according to the configuration information received from the target IAB host node-CU Yes, the third BAP route identifier is used for downlink data transmission on the target path.

As an implementation method, the BAP address in the third BAP routing identifier is the BAP address of the first IAB node on the target path, that is, the BAP address in the third BAP routing identifier is the target IAB host-CU is the first IAB node Assigned BAP address. For example, referring to FIG. 6 , the BAP address in the third BAP routing identifier is the BAP address allocated by the IAB host node 2-CU to the IAB node 1 .

As another implementation method, the BAP address in the third BAP routing identifier is the BAP address allocated by the target IAB owner-CU to the subordinate nodes of the first IAB node. Moreover, the first IAB node may obtain in advance from the source IAB host-CU or the target IAB host-CU the BAP address allocated by the target IAB host-CU to the subordinate nodes of the first IAB node. For example, referring to FIG. 6 , the BAP address in the third BAP routing identifier is the BAP address allocated by the IAB host node 2-CU to the IAB node 6 .

Step 1302, the first IAB node replaces the third BAP routing identifier in the downlink data packet with the fourth BAP routing identifier.

The BAP address in the fourth BAP routing identifier is the BAP address allocated by the source IAB host node-CU to the subordinate nodes of the first IAB node. For example, referring to FIG. 6 , the BAP address in the fourth BAP routing identifier is the BAP address allocated by the IAB host node 1-CU to the IAB node 6 .

As an implementation method, the first configuration information in the first RRC message received by the first IAB node further includes the fourth BAP routing identifier. Optionally, the fourth BAP route identifier in the first configuration information has a corresponding relationship with the foregoing third BAP route identifier.

As an alternative implementation method of step 1302, the first IAB node may still retain the third BAP routing identifier, and then add a fourth BAP routing identifier in the header of the downlink data packet.

Step 1303, the first IAB node determines that the first RRC message has been received, and the first IAB node has not received the first information from the IAB host node-CU (i.e., the target IAB host node-CU), according to the fourth BAP routing identifier in The BAP address determines the next hop node of the first IAB node.

That is, when the rerouting trigger condition is met, the first IAB node performs rerouting according to the BAP address in the fourth BAP routing identifier, and the rerouting node is the determined next-hop node of the first IAB node. The rerouting trigger condition is: the first IAB node determines to receive the first RRC message, and the first IAB node does not receive the first information from the IAB host node-CU.

For the meaning of the first information here, refer to the foregoing description, and details are not repeated here.

Step 1304, the first IAB node sends a downlink data packet to the next-hop node.

According to the above solution, after the migrating IAB node is switched to the target parent node, and before the migration of the transport network layer between the migrating IAB node and the subordinate IAB node on the target path of the migrating IAB node and the IAB host node-CU is completed, the first After the IAB node receives the downlink data packet, when it is determined that the rerouting trigger condition is met, rerouting is performed according to the BAP address in the fourth BAP routing identifier. In this way, it can be ensured that the received downlink data packets are sent successfully and packet loss is avoided.

2. The data transmission method of the subordinate IAB node of the migrated IAB node

Hereinafter, the first IAB node is used to represent the subordinate node of the migrated IAB node. The first IAB node is, for example, the IAB node 2 and the IAB node 3 in FIG. 5 or FIG. 6 . And, before the first IAB node receives the uplink data packet or the downlink data packet, it has received the first RRC message from the parent node of the first IAB node (hereinafter referred to as the second IAB node) or the IAB host node-CU, The first RRC message includes first configuration information.

The information carried in the first configuration information is similar to the information carried in the first configuration information received by the above-mentioned migrated IAB node, and reference may be made to the foregoing description.

Regardless of the topology update scenario within the host of the IAB network or the topology update scenario of the IAB network across hosts, in the uplink direction, the processing method of the received uplink data packet by the subordinate node of the migrated IAB node is the same as the above-mentioned embodiment of FIG. 9 The processing method for the received uplink data packet by the migrating IAB node is similar, and will not be repeated here.

Regardless of the topology update scenario within the host of the IAB network or the topology update scenario of the IAB network across hosts, in the uplink direction, the processing method of the uplink data packets generated by the subordinate nodes of the migrated IAB node is the same as the above-mentioned embodiment of FIG. 10 The processing method of the uplink data packet generated by the migrating IAB node is similar, and will not be repeated here.

Regardless of the topology update scenario within the host of the IAB network or the topology update scenario of the IAB network across hosts, in the uplink direction, the processing method of the subordinate node of the migrated IAB node to the received downlink data packet is the same as the above-mentioned embodiment of FIG. 11 The processing method of the received downlink data packet by the migrating IAB node is similar, and will not be repeated here.

It can be understood that, in order to realize the functions in the foregoing embodiments, the migrated IAB node or the subordinate nodes of the migrated IAB node includes corresponding hardware structures and/or software modules for performing various functions. Those skilled in the art should easily realize that the present application can be implemented in the form of hardware or a combination of hardware and computer software with reference to the units and method steps of the examples described in the embodiments disclosed in the present application. Whether a certain function is executed by hardware or computer software drives the hardware depends on the specific application scenario and design constraints of the technical solution.

FIG. 14 and FIG. 15 are schematic structural diagrams of possible communication devices provided by the embodiments of the present application. These communication devices can be used to realize the function of migrating the IAB node or the subordinate node of the migrating IAB node in the above method embodiment, so the beneficial effects of the above method embodiment can also be realized. In the embodiment of the application, the communication device may be the migration IAB node or the subordinate node of the migration IAB node in the embodiment of the application, or a module (such as a chip) applied to the migration IAB node, or a module (such as a chip) applied to the migration A module (such as a chip) of a subordinate node of the IAB node.

As shown in FIG. 14 , a communication device 1400 includes a processing unit 1410 and a transceiver unit 1420 . The communication device 1400 is configured to realize the function of migrating an IAB node or a subordinate node of the migrating IAB node in the foregoing method embodiments.

In the first embodiment, when the communication device 1400 is used to implement the function of migrating an IAB node in the above method embodiment: the processing unit 1410 is configured to determine that a first condition is met, and the first condition includes: the first IAB node A first RRC message from the IAB host CU is received, and the first IAB node switches from the source parent node of the first IAB node to the target parent node of the first IAB node according to the first RRC message. The transceiving unit 1420 is configured to send indication information to the second IAB node when the first condition is satisfied, where the indication information is used to trigger the second RRC message in the second IAB node to take effect. Or, when the first condition is satisfied, the first IAB node sends the second RRC message to the second IAB node. Wherein, the first RRC message includes first configuration information, the first configuration information is used for transport network layer migration between the first IAB node and the IAB host CU, and the second RRC message includes second configuration information, the The second configuration information is used for transport network layer migration between the second IAB node and the IAB host CU. The second IAB node is a child node of the first IAB node, the source parent node and the target parent node are connected to different IAB host DUs, and the first IAB node is connected to the IAB host DU through the different IAB host DUs before and after switching The IAB hosts the CU.

As a possible implementation method, the first condition further includes: the first IAB node has not received the first information from the IAB host CU, the first information is used for data transmission after the first IAB node switches, the The first information includes one or more of BAP route mapping configuration, BH RLC CH mapping configuration, or BAP route identification configuration.

As a possible implementation method, the first condition further includes: the first IAB node has not completed the transport network layer migration between the first IAB node and the IAB host CU according to the first configuration information.

As a possible implementation method, different IAB host DUs connected to the source parent node and the target parent node belong to the IAB host CU, and the first configuration information includes the first BAP routing identifier. The transceiver unit 1420 is configured to receive an uplink data packet, the uplink data packet includes a second BAP routing identifier, and when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, according to the The first BAP route identifier sends the uplink data packet.

As a possible implementation method, the transceiver unit 1420 is configured to: when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, and the first information has not been received from the IAB host CU , sending the uplink data packet according to the first BAP route identifier. Wherein, the first information is used for data transmission after the first IAB node switches, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration.

As a possible implementation method, the IAB host DU connected to the source parent node belongs to the IAB host CU, and the IAB host DU connected to the target parent node belongs to another IAB host CU different from the IAB host CU. A configuration message includes a first BAP routing identifier. The transceiver unit 1420 is configured to receive an uplink data packet, and the uplink data packet includes the second BAP routing identifier. The processing unit 1410 is configured to replace the second BAP routing identifier in the downlink data packet with the BAP address assigned by the IAB host CU to the first IAB node when the BAP address in the second BAP routing identifier is the same The first BAP route identifier. The transceiver unit 1420 is configured to send the uplink data packet according to the first BAP route identifier.

As a possible implementation method, the transceiver unit 1420 is configured to: when the BAP address in the second BAP routing identifier is the same as the BAP address of the first IAB node, and the first information has not been received from the IAB host CU, the The first IAB node sends the uplink data packet according to the first BAP route identifier. Wherein, the first information is used for data transmission after the first IAB node switches, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration.

As a possible implementation method, the first configuration information further includes the identifier of the BH RLC CH. The processing unit 1410 is configured to determine a next-hop node of the first IAB node corresponding to the first BAP routing identifier. The transceiver unit 1420 is configured to send the uplink data packet to the next-hop node on the BH RLC CH.

As a possible implementation method, the next-hop node is the default parent node of the first IAB node. Alternatively, the first configuration information further includes the identifier of the next-hop node.

As a possible implementation method, the different IAB host DUs connected to the source parent node and the target parent node belong to the IAB host CU, and the transceiver unit 1420 is used to receive the downlink data packet, the downlink data packet contains the first Three BAP routing identifiers. The processing unit 1410 is configured to determine that the first RRC message is received, and the first IAB node has not received the first information from the IAB host CU, and determine the first IAB according to the BAP address in the third BAP routing identifier The node's next hop node. The transceiver unit 1420 is configured to send the downlink data packet to the next-hop node. Wherein, the first information is used for data transmission after the first IAB node switches, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration.

As a possible implementation method, the IAB host DU connected to the source parent node belongs to the IAB host CU, and the IAB host DU connected to the target parent node belongs to another IAB host CU different from the IAB host CU. A configuration message includes a fourth BAP routing identifier. The transceiver unit 1420 is configured to receive a downlink data packet, the downlink data packet includes a third BAP routing identifier, and the BAP address in the third BAP routing identifier is the BAP address of the first IAB node. The processing unit 1410 is configured to replace the third BAP routing identifier in the downlink data packet with the fourth BAP routing identifier. The first IAB node determines that the first RRC message has been received, and the first IAB node has not received the first information from the IAB host CU, and determines the first IAB node according to the BAP address in the fourth BAP routing identifier next hop node. The transceiver unit 1420 is configured to send the downlink data packet to the next-hop node. Wherein, the first information is used for data transmission after the first IAB node switches, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration.

As a possible implementation method, the first configuration information includes a new IP address allocated for the first IAB node.

As a possible implementation method, the first configuration information includes the first BAP routing identifier. The processing unit 1410 is configured to determine a next-hop node of the first IAB node corresponding to the first BAP routing identifier. The transceiver unit 1420 is configured to send an uplink data packet to the next-hop node, and the uplink data packet includes the first BAP routing identifier.

In the second embodiment, when the communication device 1400 is used to implement the function of migrating the subordinate nodes of the IAB node in the above method embodiment: the processing unit 1410 is used to determine that the first condition is satisfied, and the first condition includes: the first An IAB node receives the first indication information or the first RRC message from the second IAB node, the second IAB node is the parent node of the first IAB node, and the first indication information is used to trigger the first IAB node The first RRC message takes effect. The transceiving unit 1420 is configured to send second indication information to the third IAB node when the first condition is met, where the second indication information is used to trigger a second RRC message in the third IAB node to take effect. Alternatively, the transceiver unit 1420 is configured to send the second RRC message to the third IAB node when the first condition is met, and the third IAB node is a child node of the first IAB node. Wherein, the first RRC message includes first configuration information, the first configuration information is used for transport network layer migration between the first IAB node and the IAB host CU, and the second RRC message includes second configuration information, the first The second configuration information is used for transport network layer migration between the third IAB node and the IAB host CU, and the first IAB node is connected to the IAB host CU through different IAB host DUs before and after transport network layer migration.

As a possible implementation method, the first condition further includes: the first IAB node has not received the first information from the second IAB node, and the first information is used for the first IAB node after the migration of the transport network layer For data transmission, the first information includes one or more of BAP route mapping configuration, BH RLC CH mapping configuration, or BAP route identification configuration.

As a possible implementation method, the first condition further includes: the first IAB node has not completed the transport network layer migration between the first IAB node and the IAB host CU according to the first configuration information.

As a possible implementation method, the first configuration information includes the first BAP routing identifier. The transceiver unit 1420 is configured to receive an uplink data packet, the uplink data packet includes a second BAP routing identifier, and when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, according to the The first BAP route identifier sends the uplink data packet.

As a possible implementation method, when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, and the first IAB node has not received the first information from the second IAB node , the transceiver unit 1420, configured to send the uplink data packet according to the first BAP routing identifier. Wherein, the first information is used for data transmission after the first IAB node switches, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration.

As a possible implementation method, the first configuration information further includes the identifier of the BH RLC CH. The processing unit 1410 is configured to determine a next-hop node of the first IAB node corresponding to the first BAP routing identifier. The transceiver unit 1420 is configured to send the uplink data packet to the next-hop node on the BH RLC CH.

As a possible implementation method, the next-hop node is the default parent node of the first IAB node. Alternatively, the first configuration information further includes the identifier of the next-hop node.

As a possible implementation method, the transceiving unit 1420 is configured to receive a downlink data packet, and the downlink data packet includes the third BAP routing identifier. The processing unit 1410 is configured to determine that the first RRC message is received, and the first IAB node has not received the first information from the IAB host CU, and determine the first IAB according to the BAP address in the third BAP routing identifier The node's next hop node. The transceiver unit 1420 is configured to send the downlink data packet to the next-hop node. Wherein, the first information is used for data transmission after the first IAB node switches, and the first information includes one or more of BAP routing mapping configuration, BH RLC CH mapping configuration or BAP routing identification configuration.

As a possible implementation method, the first configuration information includes a new IP address allocated for the first IAB node.

More detailed descriptions of the processing unit 1410 and the transceiver unit 1420 can be directly obtained by referring to relevant descriptions in the foregoing method embodiments, and details are not repeated here.

As shown in FIG. 15 , a communication device 1500 includes a processor 1510 and an interface circuit 1520 . The processor 1510 and the interface circuit 1520 are coupled to each other. It can be understood that the interface circuit 1520 may be a transceiver or an input/output interface. Optionally, the communication device 1500 may further include a memory 1530 for storing instructions executed by the processor 1510 or storing input data required by the processor 1510 to execute the instructions or storing data generated by the processor 1510 after executing the instructions.

When the communication device 1500 is used to implement the aforementioned method embodiments, the processor 1510 is used to implement the functions of the processing unit 1410 described above, and the interface circuit 1520 is configured to implement the functions of the transceiver unit 1420 described above.

When the above communication device is a module applied to an IAB node, the module implements the function of the IAB node in the above method embodiment. This module receives information from other modules in the IAB node (such as radio frequency modules or antennas), and the information is sent to the IAB node by the terminal or other IAB nodes; or, the module sends information to other modules in the IAB node (such as radio frequency modules or antenna) to send information, the information is sent by the IAB node to the terminal or other IAB nodes. The module here can be a baseband chip of an IAB node, or a CU, DU or other modules.

It can be understood that the processor in the embodiment of the present application may be a central processing unit (Central Processing Unit, CPU), and may also be other general processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), Field Programmable Gate Array (Field Programmable Gate Array, FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. A general-purpose processor can be a microprocessor, or any conventional processor.

The method steps in the embodiments of the present application may be implemented by means of hardware, or may be implemented by means of a processor executing software instructions. Software instructions can be composed of corresponding software modules, and software modules can be stored in random access memory, flash memory, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, registers, hard disk, removable hard disk, compact disc read-only memory (CD-ROM) or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. Of course, the storage medium may also be a component of the processor. The processor and storage medium can be located in the ASIC. In addition, the ASIC may be located in the migrating IAB node or a subordinate node of the migrating IAB node. Certainly, the processor and the storage medium may also exist in the migration IAB node or a subordinate node of the migration IAB node as discrete components.

In the above embodiments, all or part of them may be implemented by software, hardware, firmware or any combination thereof. When implemented using software, it may be implemented in whole or in part in the form of a computer program product. The computer program product comprises one or more computer programs or instructions. When the computer program or instructions are loaded and executed on the computer, the processes or functions described in the embodiments of the present application are executed in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, a base station, a terminal or other programmable devices. The computer program or instructions may be stored in or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer program or instructions may be downloaded from a website, computer, A server or data center transmits to another website site, computer, server or data center by wired or wireless means. The computer-readable storage medium may be any available medium that can be accessed by a computer, or a data storage device such as a server or a data center integrating one or more available media. The available medium may be a magnetic medium, such as a floppy disk, a hard disk, or a magnetic tape; it may also be an optical medium, such as a digital video disk; and it may also be a semiconductor medium, such as a solid state disk. The computer readable storage medium may be a volatile or a nonvolatile storage medium, or may include both volatile and nonvolatile types of storage media.

In each embodiment of the present application, if there is no special explanation and logical conflict, the terms and/or descriptions between different embodiments are consistent and can be referred to each other, and the technical features in different embodiments are based on their inherent Logical relationships can be combined to form new embodiments.

In this application, "at least one" means one or more, and "multiple" means two or more. "And/or" describes the association relationship of associated objects, indicating that there may be three types of relationships, for example, A and/or B, which can mean: A exists alone, A and B exist simultaneously, and B exists alone, where A, B can be singular or plural. In the text description of this application, the character "/" generally indicates that the contextual objects are an "or" relationship; in the formulas of this application, the character "/" indicates that the contextual objects are a "division" Relationship.

It can be understood that the various numbers involved in the embodiments of the present application are only for convenience of description, and are not used to limit the scope of the embodiments of the present application. The size of the serial numbers of the above-mentioned processes does not mean the order of execution, and the execution order of each process should be determined by its functions and internal logic.

Claims (24)

1. A method of communication, comprising:

the first access backhaul integrated IAB node determines that a first condition is satisfied, where the first condition includes: the first IAB node receives a first Radio Resource Control (RRC) message from an IAB host Centralized Unit (CU), and the first IAB node is switched from a source parent node of the first IAB node to a target parent node of the first IAB node according to the first RRC message;

when the first condition is met, the first IAB node sends indication information to a second IAB node, wherein the indication information is used for triggering a second RRC message in the second IAB node to take effect; or, when the first condition is satisfied, the first IAB node sends the second RRC message to the second IAB node;

wherein the first RRC message comprises first configuration information for transport network layer migration between the first IAB node and the IAB anchor CU, and the second RRC message comprises second configuration information for transport network layer migration between the second IAB node and the IAB anchor CU; the second IAB node is a child node of the first IAB node, the source father node and the target father node are connected to different IAB-hosted distributed units DU, and the first IAB node is connected to the IAB-hosted CU through the different IAB-hosted DUs before and after the handover.

2. The method of claim 1, wherein the first condition further comprises:

the first IAB node does not receive first information from the IAB host CU, the first information being used for data transmission after the first IAB node is handed over, the first information including one or more of a backhaul adaptation protocol, BAP, route mapping configuration, a backhaul radio link control channel, BH, RLC, CH, mapping configuration, or BAP route identification configuration.

3. The method of claim 1 or 2, wherein the first condition further comprises:

the first IAB node does not complete transport network layer migration between the first IAB node and the IAB host CU according to the first configuration information.

4. The method of claim 1, wherein different IAB host DUs to which the source parent node and the target parent node are connected are both owned by the IAB host CU, the first configuration information comprising a first BAP route identification;

the method further comprises the following steps:

the first IAB node receives an uplink data packet, wherein the uplink data packet comprises a second BAP routing identifier;

and when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, the first IAB node sends the uplink data packet according to the first BAP routing identifier.

5. The method of claim 4, wherein when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, the first IAB node sending the uplink packet according to the first BAP routing identifier comprises:

when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, and the first IAB node does not receive first information from the IAB host CU, the first IAB node sends the uplink data packet according to the first BAP routing identifier;

the first information is used for data transmission after the first IAB node is switched, and the first information includes one or more of BAP route mapping configuration, BH RLC CH mapping configuration, or BAP route identifier configuration.

6. The method of claim 1, wherein the IAB host DU for the source parent node connection is owned by the IAB host CU, wherein the IAB host DU for the target parent node connection is owned by another IAB host CU different from the IAB host CU, and wherein the first configuration information comprises a first BAP route identification;

the method further comprises the following steps:

the first IAB node receives an uplink data packet, wherein the uplink data packet comprises a second BAP routing identifier;

when the BAP address in the second BAP route identifier is the same as the BAP address distributed by the IAB host CU to the first IAB node, the first IAB node replaces the second BAP route identifier in the downlink data packet with the first BAP route identifier;

and the first IAB node sends the uplink data packet according to the first BAP routing identifier.

7. The method of claim 6, wherein when the BAP address in the second BAP routing identifier is the same as the BAP address of the first IAB node, the first IAB node sending the uplink packet according to the first BAP routing identifier comprises:

when the BAP address in the second BAP route identifier is the same as the BAP address of the first IAB node and the first IAB node does not receive the first information from the IAB host CU, the first IAB node sends the uplink data packet according to the first BAP route identifier;

the first information is used for data transmission after the first IAB node is switched, and the first information includes one or more of BAP route mapping configuration, BH RLC CH mapping configuration, or BAP route identifier configuration.

8. The method of any of claims 4 to 7, wherein the first configuration information further comprises an identification of a BH RLC CH;

the sending, by the first IAB node, the uplink data packet according to the first BAP routing identifier includes:

the first IAB node determines a next hop node of the first IAB node corresponding to the first BAP routing identifier;

and the first IAB node sends the uplink data packet to the next hop node on the BH RLC CH.

9. The method of claim 8,

the next hop node is a default parent node of the first IAB node; or,

the first configuration information further includes an identifier of the next hop node.

10. The method of claim 1, wherein different IAB-hosting DUs to which the source parent node and the target parent node are connected are both owned by the IAB-hosting CU, the method further comprising:

the first IAB node receives a downlink data packet, wherein the downlink data packet comprises a third BAP routing identifier;

the first IAB node determines that the first RRC message is received and the first IAB node does not receive the first information from the IAB host CU, and determines a next hop node of the first IAB node according to a BAP address in the third BAP routing identifier;

the first IAB node sends the downlink data packet to the next hop node;

the first information is used for data transmission after the first IAB node is switched, and the first information includes one or more of BAP route mapping configuration, BH RLC CH mapping configuration, or BAP route identifier configuration.

11. The method of claim 1, wherein the IAB host DU for the source parent node connection is owned by the IAB host CU, wherein the IAB host DU for the target parent node connection is owned by another IAB host CU different from the IAB host CU, and wherein the first configuration information comprises a fourth BAP route identification;

the method further comprises the following steps:

the first IAB node receives a downlink data packet, wherein the downlink data packet comprises a third BAP routing identifier, and a BAP address in the third BAP routing identifier is the BAP address of the first IAB node;

replacing the third BAP routing identifier in the downlink data packet with the fourth BAP routing identifier by the first IAB node;

the first IAB node determines that the first RRC message is received and the first IAB node does not receive the first information from the IAB host CU, and determines a next hop node of the first IAB node according to a BAP address in the fourth BAP routing identifier;

the first IAB node sends the downlink data packet to the next hop node;

the first information is used for data transmission after the first IAB node is switched, and the first information includes one or more of BAP route mapping configuration, BH RLC CH mapping configuration, or BAP route identifier configuration.

12. The method of any of claims 1 to 11, wherein the first configuration information comprises a new internet protocol, IP, address allocated for the first IAB node.

13. A method of communication, comprising:

the first access backhaul integrated IAB node determines that a first condition is satisfied, where the first condition includes: the first IAB node receives first indication information or a first Radio Resource Control (RRC) message from a second IAB node, wherein the second IAB node is a parent node of the first IAB node, and the first indication information is used for triggering the first RRC message in the first IAB node to take effect;

when the first condition is met, the first IAB node sends second indication information to a third IAB node, wherein the second indication information is used for triggering a second RRC message in the third IAB node to take effect; or, when the first condition is satisfied, the first IAB node sends the second RRC message to a third IAB node, which is a child node of the first IAB node;

wherein the first RRC message includes first configuration information used for transport network layer migration between the first IAB node and an IAB-hosting centralized unit CU, the second RRC message includes second configuration information used for transport network layer migration between the third IAB node and the IAB-hosting CU, and the first IAB node is connected to the IAB-hosting CU through different IAB-hosting distributed units DU before and after transport network layer migration.

14. The method of claim 13, wherein the first condition further comprises:

the first IAB node does not receive first information from the second IAB node, the first information is used for data transmission after the first IAB node migrates in a transport network layer, and the first information includes one or more of a Backhaul Adaptation Protocol (BAP) routing mapping configuration, a backhaul radio link control channel (BH RLC CH) mapping configuration, or a BAP routing identification configuration.

15. The method of claim 13 or 14, wherein the first condition further comprises:

the first IAB node does not complete transport network layer migration between the first IAB node and the IAB host CU according to the first configuration information.

16. The method of claim 13, wherein the first configuration information includes a first BAP routing identification;

the method further comprises the following steps:

the first IAB node receives an uplink data packet, wherein the uplink data packet comprises a second BAP routing identifier;

and when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier, the first IAB node sends the uplink data packet according to the first BAP routing identifier.

17. The method of claim 16, wherein when the BAP address in the second BAP routing identity is the same as the BAP address in the first BAP routing identity, the first IAB node sending the uplink packet according to the first BAP routing identity, comprising:

when the BAP address in the second BAP routing identifier is the same as the BAP address in the first BAP routing identifier and the first IAB node does not receive the first information from the second IAB node, the first IAB node sends the uplink data packet according to the first BAP routing identifier;

the first information is used for data transmission after the first IAB node is switched, and the first information includes one or more of BAP route mapping configuration, BH RLC CH mapping configuration, or BAP route identifier configuration.

18. The method of claim 16 or 17, wherein the first configuration information further comprises an identification of a BH RLC CH;

the first IAB node sending the uplink data packet according to the first BAP route identifier includes:

the first IAB node determines a next hop node of the first IAB node corresponding to the first BAP routing identifier;

and the first IAB node sends the uplink data packet to the next hop node on the BH RLC CH.

19. The method of claim 18,

the next hop node is a default parent node of the first IAB node; or,

the first configuration information further includes an identifier of the next hop node.

20. The method of claim 13, wherein the method further comprises:

the first IAB node receives a downlink data packet, wherein the downlink data packet comprises a third BAP routing identifier;

the first IAB node determines to receive the first RRC message and does not receive the first information from the IAB host CU, and determines a next hop node of the first IAB node according to the BAP address in the third BAP routing identifier;

the first IAB node sends the downlink data packet to the next hop node;

the first information is used for data transmission after the first IAB node is switched, and the first information includes one or more of BAP route mapping configuration, BH RLC CH mapping configuration, or BAP route identifier configuration.

21. The method of any of claims 13 to 20, wherein the first configuration information comprises a new internet protocol, IP, address assigned for the first IAB node.

22. A communications device comprising means for performing a method as claimed in any one of claims 1 to 12, or means for performing a method as claimed in any one of claims 13 to 21.

23. A communications device comprising a processor and interface circuitry for receiving and transmitting signals to or from a communications device other than the communications device, the processor being configured to implement the method of any of claims 1 to 12 or to implement the method of any of claims 13 to 21 by logic circuitry or executing code instructions.

24. A computer-readable storage medium, in which a computer program or instructions is stored which, when executed by a communication apparatus, carries out the method of any one of claims 1 to 21.

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