CN111148163B

CN111148163B - Communication method and device

Info

Publication number: CN111148163B
Application number: CN201811303106.3A
Authority: CN
Inventors: 朱元萍; 戴明增; 卓义斌
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2018-11-02
Filing date: 2018-11-02
Publication date: 2021-09-14
Anticipated expiration: 2038-11-02
Also published as: CN111148163A; WO2020088472A1

Abstract

The application provides a communication method and a communication device, which are used for improving the communication efficiency of a network. The method comprises the following steps: the first node receives first indication information and/or a switching command from the second node, wherein the first indication information is used for indicating the first node to stop sending the data packet to the third node, and the switching command is used for switching the third node from the first node to the fourth node; the first node sends a first status report to the second node, wherein the first status report comprises information used for indicating the sending status of a data packet sent by the first node to the third node; the second node is a host node of the first node, the third node is a terminal or a wireless backhaul node, the first node is a node providing wireless access service for the third node before the third node is switched, the first node and/or the fourth node are wireless backhaul nodes, and the wireless backhaul nodes are used for providing wireless backhaul service for the nodes accessing the wireless backhaul nodes; the first node to the fourth node are all nodes in wireless relay communication.

Description

Communication method and device

Technical Field

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

Background

In the prior art, in order to ensure continuity of a service of a terminal during a process of switching the terminal between different base stations, after the terminal completes switching, the terminal may send a Packet Data Convergence Protocol (PDCP) status report to a target base station (or a Centralized Unit (CU) of the target base station), and the target base station (or the CU of the target base station) may resend a PDCP Data Unit (PDU) that is not correctly received by the terminal to the terminal according to the status report.

In an Integrated Access and Backhaul (IAB) network (i.e., a network including IAB nodes), there are multiple hops and multiple connection scenarios, i.e., multiple nodes (e.g., multiple IAB nodes) can serve a terminal at the same time, and the terminal can transmit a data packet through the multiple IAB nodes. In this case, if the method in the prior art is used to ensure the service continuity of the terminal, the PDCP status report may be sent to the target host base station by the terminal after the handover is completed, so that the target host base station knows the data packet that is not correctly received by the terminal, but since the terminal may transmit the data packet through the multi-hop IAB node, the method may cause the waiting time of the data packet that is not successfully received by the terminal to be longer, thereby reducing the communication efficiency of the network.

Disclosure of Invention

The embodiment of the application provides a communication method and a communication device, which are used for improving the communication efficiency of a network.

In order to achieve the above purpose, the embodiments of the present application provide the following technical solutions:

in a first aspect, a communication method is provided, including: the first node receives first indication information and/or a switching command from the second node, wherein the first indication information is used for indicating the first node to stop sending the data packet to the third node, and the switching command is used for switching the third node from the first node to the fourth node; the first node sends a first status report to the second node, wherein the first status report comprises information used for indicating the sending status of a data packet sent by the first node to the third node; the second node is a host node of the first node, the third node is a terminal or a wireless backhaul node, the first node is a node providing wireless access service for the third node before the third node is switched, the first node and/or the fourth node are wireless backhaul nodes, and the wireless backhaul nodes are used for providing wireless backhaul service for the nodes accessing the wireless backhaul nodes; the first node to the fourth node are all nodes in wireless relay communication. In the method provided by the first aspect, the first node may send the first status report to the second node when receiving the first indication information and/or the handover command, so that the second node receives the sending status of the data packet sent by the second node to the third node as soon as possible, thereby avoiding that the waiting time for the data packet which is not successfully received by the third node is too long, and improving the communication efficiency of the network. Meanwhile, the problem that the HFN between the second node and the third node is out of synchronization due to the fact that a larger interval (gap) is generated by the PDCP SN in the PDCP PDU received by the third node can be avoided.

In one possible implementation, before the first node sends the first status report to the second node, the method further includes: the first node sends a first message to the third node, the first message including information for instructing the third node to report a reception status of a data packet received from the first node; the first node receiving a second status report from the third node, the second status report including information indicating a reception status of a packet received by the third node from the first node; the first node generates a first status report according to the second status report. The possible implementation mode can enable the second node to more accurately determine whether the data packet between the first node and the third node is successfully transmitted.

In one possible implementation, the sending, by the first node, the first status report to the second node includes: the first node sends a first status report to the second node through the node between the first node and the second node, and the node between the first node and the second node is used for converting the information in the status report received from the previous hop node into the information which can be identified by the next hop node, placing the information in the status report and sending the information to the next hop node. According to the possible implementation mode, in a scene that the second node sends the data packet through the first node, the node between the first node and the second node converts the information in the received status report and then sends the converted information to the next hop node until the converted information is transmitted to the second node, so that the second node can know the sending state sent by the second node in the data packet sent by the second node according to the received status report, and the sending state sent by the first node after the converted information is transmitted by the intermediate node is avoided that the second node cannot correctly decode the information in the received status report.

In a possible implementation manner, the status report between any two adjacent nodes in the path between the first node and the previous hop node of the second node includes second indication information, and the second indication information included in one status report is used to indicate the node receiving the status report to convert the information in the status report into information recognizable by the next hop node of the node receiving the status report, and send the information to the next hop node. By adding the second indication information to the status report, the node can distinguish the status report in a common communication scenario (i.e., a communication scenario in which the third node does not perform handover) from the status report in a communication scenario in which the third node performs handover, so that the status report can be correctly processed.

In one possible implementation manner, the generating, by the first node, the first status report according to the second status report includes: the first node generates a first status report according to the corresponding relation of the RLC SNs between the first link and the second link and the RLC SNs contained in the second status report; the first link is a link between the first node and the third node, the second link is a link between the first node and the fifth node, the fifth node is a node providing wireless access service for the first node, and the RLC SN is the SN of the RLC SDU. According to the possible implementation manner, the fifth node can confirm the state received by the third node after being transmitted by the first node in the data packet sent by the fifth node according to the first state report, so that the fifth node can not correctly interpret the information in the first state report.

In one possible implementation manner, the generating, by the first node, the first status report according to the second status report includes: the first node generates a first status report according to the corresponding relation of the RLC SN between the first link and the first path and the RLC SN contained in the second status report; the first link is a link between the first node and the third node, the first path is a path between the first node and the second node, and the RLC SN is the SN of the RLC SDU. The possible implementation manner can enable the second node to generate a first status report according to the corresponding relation of the RLC SN between the first link and the first path and the second status report and then send the first status report to the second node when the second node sends the data packet to the third node through the first node, and the second node can confirm the state received by the third node after the data packet is transmitted by the first node in the data packet sent by the second node according to the first status report, so that the second node can not correctly read the information in the first status report.

In one possible implementation, the method further includes: and the first node sends the cached uplink data packet sent by the third node to the second node and sends third indication information to the second node, wherein the third indication information is used for indicating that the first node has sent all the uplink data packets sent by the cached third node. The possible implementation manner provides a method for the first node to send the cached uplink data packet sent by the third node, and guarantees the continuity of the uplink service, so that the third node does not need to resend the sent uplink data packet after switching, and the waste of air interface resources is avoided.

In a possible implementation manner, the first status report includes an identifier of the first node, where the identifier of the first node is used to indicate that the information of the transmission status of the data packet included in the first status report is the information of the transmission status of the data packet transmitted by the first node. In this possible implementation manner, in a scenario where the second node sends the data packet via at least one intermediate node, the second node may determine, according to the identifier of the first node in the first status report, that the received status report indicates the transmission status of the data packet transmitted by the first node in the data packet sent by the second node.

In a possible implementation manner, the first status report further includes an identifier of a third node, where the identifier of the third node is used to indicate that the information of the transmission state of the data packet included in the first status report is the information of the transmission state of the data packet transmitted to the third node; or, the first status report further includes an identifier of the third node and an identifier of at least one radio bearer of the third node, where the identifier of the third node and the identifier of the at least one radio bearer of the third node are used to indicate that the information of the transmission status of the data packet included in the first status report is the information of the transmission status of the data packet transmitted to the third node through the at least one radio bearer. The possible implementation manner can enable the second node to determine the transmission state of the data packet transmitted to the third node in the data packet transmitted by the second node according to the identifier of the third node in the received status report when the second node transmits data to the third node through at least one intermediate node; or, according to the identifier of the third node and the identifier of at least one radio bearer of the third node in the received status report, determining the transmission status of the data packet sent by the second node to the third node via the radio bearer of the third node in the data packet sent by the second node.

In a second aspect, a communication device is provided, which has the function of implementing any one of the methods provided in the first aspect. The function can be realized by hardware, and can also be realized by executing corresponding software by hardware. The hardware or software includes one or more units corresponding to the above functions. The communication device may be in the form of a chip product.

In a third aspect, a communication method is provided, including: the third node receives a switching command, and the switching command is used for switching the third node from the first node to the fourth node; the third node sends a third status report to the second node; in a case where the third node is a terminal, the third status report includes information indicating a reception status of a packet received by the third node from the first node; alternatively, in case the third node is a wireless backhaul node, the third status report comprises: information for indicating a reception state of a packet received by the third node from the first node, or information for indicating a transmission state of a downlink packet transmitted by the third node; the first node is a node which provides wireless access service for the third node before the third node is switched, the second node is a host node of the first node, the first node and/or the fourth node are wireless backhaul nodes, and the wireless backhaul nodes are used for providing wireless backhaul service for the nodes which are wirelessly accessed into the wireless backhaul nodes; the first node to the fourth node are all nodes in wireless relay communication. In the method provided by the third aspect, the third node may send the third status report to the second node when receiving the handover command (i.e., not after the handover is completed), so that the second node receives the sending status or the receiving status of the data packet as soon as possible, thereby avoiding an excessively long waiting time for unsuccessfully receiving or unsuccessfully sending the data packet, and improving the communication efficiency of the network. Meanwhile, the problem that the hyper frame number between the second node and the third node is out of step due to a larger gap (gap) generated by the PDCP SN of the PDCP PDU received by the third node can be avoided.

In one possible implementation, the third node sends a third status report to the second node, including: and the third node sends a third status report to the second node through the node between the third node and the second node, and the node between the third node and the second node is used for converting the information in the status report received from the previous hop node into the information which can be identified by the next hop node, placing the information in the status report and sending the information to the next hop node. According to the possible implementation mode, in a scene that the second node sends the data packet to the third node through at least one intermediate node, the information in the received state report is converted and then sent to the next hop through the node between the third node and the second node until the state report is transmitted to the second node, so that the second node can confirm the state received or sent by the third node in the data packet sent by the second node according to the received state report, and the second node can be prevented from being incapable of correctly reading the information in the received state report.

In a possible implementation manner, the status report between any two adjacent nodes in the path between the third node and the previous hop node of the second node includes fourth indication information, and the fourth indication information included in one status report is used to indicate the node receiving the status report to convert the information in the status report into information recognizable by the next hop node of the node receiving the status report, and send the information to the next hop node. In this possible implementation manner, by adding the fourth indication information to the status report, the node can distinguish the status report in the normal communication scenario (i.e., the communication scenario in which the third node does not perform handover) from the status report in the communication scenario in which the third node performs handover, so that the node can correctly process the status report.

In one possible implementation, the third node is a wireless backhaul node, and the method further includes: the third node sends a second message to the terminal served by the third node, the second message including information for instructing the terminal served by the third node to report a reception status of the data packet received from the third node; the third node receiving status reports of terminals served by the third node, the status report of one terminal including information indicating a reception status of a packet received by the terminal from the third node; the third node sends a fourth status report to the second node according to the status report of the terminal served by the third node, the fourth status report including information indicating a reception status of a data packet received by the terminal served by the third node from the third node. The possible implementation mode can enable the second node to accurately know the latest information of the receiving state of the data packet received by the terminal from the third node.

In a possible implementation manner, the third node sends a fourth status report to the second node according to the status report of the terminal served by the third node, including: the third node generates a fourth status report according to the corresponding relation between the RLC SN between the third link and the second path and the RLC SN contained in the status report of the terminal served by the third node, and sends the fourth status report to the second node, wherein the third link is the link between the third node and the terminal served by the third node, the second path is the path between the third node and the second node, and the RLC SN is the SN of the RLC SDU; or, the third node generates a fourth status report according to the corresponding relationship between the RLC SNs of the third link and the fourth link and the RLC SN included in the status report of the terminal served by the third node, and sends the fourth status report to the second node through the node between the third node and the second node, the node between the third node and the second node is configured to convert information in the status report received from the previous-hop node into information that can be recognized by the next-hop node, and place the information in the status report and send the information to the next-hop node, the third link is a link between the third node and the terminal served by the third node, the fourth link is a link between the third node and the first node, and the RLC SN is an SN of an RLC SDU. According to the possible implementation manner, the third node generates a fourth status report according to the corresponding relation between the third link and the RLC SN of the second path and sends the fourth status report to the second node, so that the second node can acquire the status received by a terminal served by the third node in a data packet sent by the second node after transmission of the third node according to the fourth status report, and the second node can avoid the problem that the received fourth status report cannot be correctly interpreted; or, the third node generates a fourth status report according to the corresponding relationship between the third link and the RLC SN of the fourth link, and the node between the third node and the second node converts the information in the received status report and sends the information to the next hop until the status report is transmitted to the second node, so that the second node can know the status received by the terminal served by the third node in the data packet sent by the second node according to the received status report, and the second node cannot correctly interpret the information in the received status report. In a possible implementation manner, the fourth status report includes an identifier of the terminal served by the third node, where the identifier of the terminal served by the third node is used to indicate that the information of the reception state of the data packet included in the fourth status report is the information of the reception state of the data packet received by the terminal served by the third node; or the fourth status report includes the identifier of the terminal served by the third node and the identifier of the at least one radio bearer of the terminal served by the third node, and the identifier of the terminal served by the third node and the identifier of the at least one radio bearer of the terminal served by the third node are used to indicate that the information of the reception state of the data packet included in the fourth status report is the information of the reception state of the data packet received by the terminal served by the third node through the at least one radio bearer. In this possible implementation manner, by including the identifier of the terminal served by the third node in the fourth status report, the node receiving the fourth report status can determine which terminal node specifically describes the receiving status in the fourth status report; or, by including the identifier of at least one radio bearer of the terminal served by the third node in the fourth status report, the node receiving the fourth status report can determine, according to the fourth status report, a reception status of the data packet received by the terminal served by the third node through a different radio bearer.

In a possible implementation manner, the third status report includes an identifier of the third node; when the third node is a terminal, the identifier of the third node is used for indicating that the information of the receiving state of the data packet contained in the third status report is the information of the receiving state of the data packet received by the third node; or, in a case that the third node is a wireless backhaul node and the third status report includes information indicating a reception status of a data packet received by the third node from the first node, the information indicating the reception status of the data packet included in the third status report is information indicating a reception status of the data packet received by the third node; or, when the third node is a wireless backhaul node and the third status report includes information indicating a transmission status of a downlink data packet transmitted by the third node, the identifier of the third node is used to indicate that the information indicating the transmission status of the downlink data packet included in the third status report is the information indicating the transmission status of the downlink data packet transmitted by the third node. This possible implementation manner enables the node receiving the third status report to know that the third status report includes the status of receiving/sending the data packet by the third node.

In a fourth aspect, a communication apparatus having a function of implementing any one of the methods provided in the third aspect is provided. The function can be realized by hardware, and can also be realized by executing corresponding software by hardware. The hardware or software includes one or more units corresponding to the above functions. The communication device may be the third node, or a component or device in the third node, or may be a system chip in the third node, etc.

In a fifth aspect, a communication method is provided, which is applied to a second node, where the second node includes a centralized unit and a distributed unit, and the method includes: the distributed unit receives a fifth status report, wherein the fifth status report is a status report which is sent to the second node by a node between the first node and the second node and is used for converting information in the first status report into information which can be identified by the second node, and the first status report comprises information used for indicating the sending status of a data packet sent to a third node by the first node; the distributed unit sends a third message to the centralized unit according to the fifth status report, wherein the third message comprises information used for indicating the sending status of a data packet sent by the first node to a third node; the second node is a host node of the first node, the third node is a node switched from the first node to a fourth node, the first node is a node providing wireless access service for the third node before the third node is switched, the first node and/or the fourth node is a wireless backhaul node, the third node is a terminal or a wireless backhaul node, and the wireless backhaul node is used for providing wireless backhaul service for a node wirelessly accessed to the wireless backhaul node; the first node to the fourth node are all nodes in wireless relay communication. By the method provided by the fifth aspect, the centralized unit of the second node can know the sending state of the data packet sent by the first node to the third node, so that the centralized unit of the second node can continue to send the unsuccessful data packet to the third node after the third node switches.

In a possible implementation manner, the fifth status report includes an identifier of the first node, where the identifier of the first node is used to indicate that the information of the transmission state of the data packet included in the fifth status report is the information of the transmission state of the data packet transmitted by the first node. By the possible method, the distributed unit of the second node can learn that the information contained in the fifth status report is the sending status of the data packet sent by the first node, and then inform the centralized unit of the second node through the third message.

In a possible implementation manner, the fifth status report further includes an identifier of the third node, where the identifier of the third node is used to indicate that the information of the transmission state of the data packet included in the fifth status report is the information of the transmission state of the data packet transmitted to the third node; or, the fifth status report further includes an identifier of the third node and an identifier of at least one radio bearer of the third node, where the identifier of the third node and the identifier of the at least one radio bearer of the third node are used to indicate that the information of the transmission status of the data packet included in the fifth status report is information of the transmission status of the data packet transmitted to the third node through the at least one radio bearer. By this possible method, the distributed unit of the second node may learn that the information included in the fifth status report is the information of the transmission status of the data packet sent to the third node, or the information of the transmission status of the data packet sent to the third node through at least one radio bearer, and then notify the centralized unit of the second node through the third message.

In a sixth aspect, a communication apparatus is provided, the communication apparatus comprising a centralized unit and a distributed unit, the distributed unit comprising: a communication unit and a processing unit; the processing unit is configured to receive a fifth status report by using the communication unit, where the fifth status report is a status report that a node between the first node and the communication device converts information in the first status report into information recognizable by the communication device and sends the information to the communication device, and the first status report includes information indicating a sending status of a packet sent by the first node to a third node; the processing unit is further configured to send, by using the communication unit, a third message to the centralized unit according to the fifth status report, where the third message includes information indicating a sending status of a packet sent by the first node to a third node; the communication device is a host node of the first node, the third node is a node switched from the first node to a fourth node, the first node is a node providing wireless access service for the third node before the third node is switched, the first node and/or the fourth node is a wireless backhaul node, the third node is a terminal or a wireless backhaul node, and the wireless backhaul node is used for providing wireless backhaul service for a node wirelessly accessed to the wireless backhaul node; the first node to the fourth node are all nodes in wireless relay communication.

In a possible implementation manner, the fifth status report includes an identifier of the first node, where the identifier of the first node is used to indicate that the information of the transmission state of the data packet included in the fifth status report is the information of the transmission state of the data packet transmitted by the first node.

In a possible implementation manner, the fifth status report further includes an identifier of the third node, where the identifier of the third node is used to indicate that the information of the transmission state of the data packet included in the fifth status report is the information of the transmission state of the data packet transmitted to the third node; or, the fifth status report further includes an identifier of the third node and an identifier of at least one radio bearer of the third node, where the identifier of the third node and the identifier of the at least one radio bearer of the third node are used to indicate that the information of the transmission status of the data packet included in the fifth status report is information of the transmission status of the data packet transmitted to the third node through the at least one radio bearer.

In a seventh aspect, a communication method is provided, which is applied to a second node, where the second node includes a centralized unit and a distributed unit, and the method includes: the distributed unit receives a first status report from a first node, wherein the first status report comprises information used for indicating the sending status of a data packet sent by the first node to a third node; the distributed unit sends a third message to the centralized unit according to the first status report, wherein the third message comprises information used for indicating the sending status of a data packet sent by the first node to a third node; the second node is a host node of the first node, the third node is a node switched from the first node to a fourth node, the first node is a node providing wireless access service for the third node before the third node is switched, the first node and/or the fourth node is a wireless backhaul node, the third node is a terminal or a wireless backhaul node, and the wireless backhaul node is used for providing wireless backhaul service for a node wirelessly accessed to the wireless backhaul node; the first node to the fourth node are all nodes in wireless relay communication. By the method provided by the aspect, the centralized unit of the second node can know the sending state of the data packet sent by the first node to the third node, so that the centralized unit of the second node can continue to send the unsuccessful data packet to the third node after the third node is switched.

In a possible implementation manner, the first status report includes an identifier of the first node, where the identifier of the first node is used to indicate that the information of the transmission state of the data packet included in the first status report is the information of the transmission state of the data packet transmitted by the first node. By the possible method, the distributed unit of the second node can acquire the sending state of the data packet sent by the first node as the information contained in the first status report, and then notify the centralized unit of the second node through the third message.

In a possible implementation manner, the first status report further includes an identifier of the third node, where the identifier of the third node is used to indicate that the information of the transmission state of the data packet included in the first status report is the information of the transmission state of the data packet transmitted to the third node; or, the first status report further includes an identifier of the third node and an identifier of at least one radio bearer of the third node, where the identifier of the third node and the identifier of the at least one radio bearer of the third node are used to indicate that the information of the transmission status of the data packet included in the first status report is information of the transmission status of the data packet transmitted to the third node through the at least one radio bearer. By this possible method, the distributed unit of the second node may learn that the information included in the first status report is the information of the transmission status of the data packet sent to the third node, or the information of the transmission status of the data packet sent to the third node through at least one radio bearer.

In an eighth aspect, there is provided a communication apparatus comprising a centralized unit and a distributed unit, the distributed unit comprising: a communication unit and a processing unit; the processing unit is configured to receive, by using the communication unit, a first status report from a first node, where the first status report includes information indicating a transmission status of a packet transmitted by the first node to a third node; the processing unit is further configured to send, by using the communication unit, a third message to the centralized unit according to the first status report, where the third message includes information indicating a sending status of a packet sent by the first node to a third node; the communication device is a host node of the first node, the third node is a node switched from the first node to a fourth node, the first node is a node providing wireless access service for the third node before the third node is switched, the first node and/or the fourth node is a wireless backhaul node, the third node is a terminal or a wireless backhaul node, and the wireless backhaul node is used for providing wireless backhaul service for a node wirelessly accessed to the wireless backhaul node; the first node to the fourth node are all nodes in wireless relay communication.

In a possible implementation manner, the first status report includes an identifier of the first node, where the identifier of the first node is used to indicate that the information of the transmission state of the data packet included in the first status report is the information of the transmission state of the data packet transmitted by the first node.

In a possible implementation manner, the first status report further includes an identifier of the third node, where the identifier of the third node is used to indicate that the information of the transmission state of the data packet included in the first status report is the information of the transmission state of the data packet transmitted to the third node; or, the first status report further includes an identifier of the third node and an identifier of at least one radio bearer of the third node, where the identifier of the third node and the identifier of the at least one radio bearer of the third node are used to indicate that the information of the transmission status of the data packet included in the first status report is information of the transmission status of the data packet transmitted to the third node through the at least one radio bearer.

In a ninth aspect, a communication method is provided, which is applied to a second node, where the second node includes a centralized unit and a distributed unit, and the method includes: the distributed unit receiving a third status report from a third node; the distributed unit sending a fourth message to the centralized unit according to the third status report; in a case where the third node is a terminal, the third status report includes information indicating a reception status of a packet received by the third node from the first node, and the fourth message includes information indicating a reception status of a packet received by the third node from the first node; or, in a case that the third node is a wireless backhaul node, the third status report includes information indicating a reception status of a data packet received by the third node from the first node, and the fourth message includes information indicating a reception status of a data packet received by the third node from the first node; or, in a case that the third node is a wireless backhaul node, the third status report includes information for indicating a sending status of a downlink data packet sent by the third node, and the fourth message includes information for indicating a sending status of a downlink data packet sent by the third node; the third node is a node switched from the first node to the fourth node, the first node is a node providing wireless access service for the third node before the third node is switched, the second node is a host node of the first node, the first node and/or the fourth node are wireless backhaul nodes, and the wireless backhaul nodes are used for providing wireless backhaul service for nodes wirelessly accessing the wireless backhaul nodes; the first node to the fourth node are all nodes in wireless relay communication. By the method provided by the ninth aspect, the centralized unit of the second node can know the packet receiving/sending state of the third node, so that the centralized unit of the second node can continue to send the unsuccessfully sent packet to the third node after the third node switches, or continue to send the unsuccessfully sent packet to the terminal via the third node.

In a possible implementation manner, the third status report includes an identifier of the third node; when the third node is a terminal, the identifier of the third node is used to indicate that the information of the reception status of the data packet included in the third status report is the information of the reception status of the data packet received by the third node; or, in a case that the third node is a wireless backhaul node and the third status report includes information indicating a reception status of a data packet received by the third node from the first node, the information indicating the reception status of the data packet included in the third status report is information indicating a reception status of the data packet received by the third node; or, when the third node is a wireless backhaul node and the third status report includes information indicating a transmission status of a downlink data packet sent by the third node, the identifier of the third node is used to indicate that the information indicating the transmission status of the downlink data packet included in the third status report is the information indicating the transmission status of the downlink data packet sent by the third node. By the possible method, the distributed unit of the second node can know that the information contained in the third status report is the status of receiving/sending the data packet by the third node.

In one possible implementation, the third node is a wireless backhaul node, and the method further includes: receiving, by the distributed unit, a fourth status report from the third node, the fourth status report including information indicating a reception status of a packet received by a terminal served by the third node from the third node; and the distributed unit sends a fifth message to the centralized unit according to the fourth status report, wherein the fifth message comprises information used for indicating the receiving status of the data packet received by the terminal served by the third node from the third node. By the possible method, the centralized unit of the second node can know the data packet receiving state of the terminal served by the third node, so that the centralized unit of the second node can continue to send the data packet which is not successfully sent to the terminal through the third node after the third node is switched.

In a possible implementation manner, the fourth status report includes an identifier of the terminal served by the third node, where the identifier of the terminal served by the third node is used to indicate that the information of the reception state of the data packet included in the fourth status report is the information of the reception state of the data packet received by the terminal served by the third node; or, the fourth status report includes an identifier of the terminal served by the third node and an identifier of at least one radio bearer of the terminal served by the third node, where the identifier of the terminal served by the third node and the identifier of the at least one radio bearer of the terminal served by the third node are used to indicate that the information of the reception state of the data packet included in the fourth status report is the information of the reception state of the data packet received by the terminal served by the third node through the at least one radio bearer. By the possible method, the distributed unit of the second node can acquire the information of the reception state of the data packet received by the terminal serving the third node, which is contained in the fourth status report, or the information of the reception state of the data packet received by the terminal serving the third node through at least one radio bearer.

In a tenth aspect, there is provided a communication apparatus comprising a centralized unit and a distributed unit, the distributed unit comprising: a communication unit and a processing unit; the processing unit is configured to receive a third status report from a third node using the communication unit; the processing unit is further configured to send a fourth message to the centralized unit using the communication unit according to the third status report; in a case where the third node is a terminal, the third status report includes information indicating a reception status of a packet received by the third node from the first node, and the fourth message includes information indicating a reception status of a packet received by the third node from the first node; or, in a case that the third node is a wireless backhaul node, the third status report includes information indicating a reception status of a data packet received by the third node from the first node, and the fourth message includes information indicating a reception status of a data packet received by the third node from the first node; or, in a case that the third node is a wireless backhaul node, the third status report includes information for indicating a sending status of a downlink data packet sent by the third node, and the fourth message includes information for indicating a sending status of a downlink data packet sent by the third node; the third node is a node that is handed over from the first node to the fourth node, the first node is a node that provides wireless access service for the third node before the third node is handed over, the communication device is a host node of the first node, the first node and/or the fourth node are wireless backhaul nodes, and the wireless backhaul nodes are used for providing wireless backhaul service for nodes that wirelessly access the wireless backhaul nodes; the first node to the fourth node are all nodes in wireless relay communication.

In a possible implementation manner, the third status report includes an identifier of the third node; when the third node is a terminal, the identifier of the third node is used to indicate that the information of the reception status of the data packet included in the third status report is the information of the reception status of the data packet received by the third node; or, in a case that the third node is a wireless backhaul node and the third status report includes information indicating a reception status of a data packet received by the third node from the first node, the information indicating the reception status of the data packet included in the third status report is information indicating a reception status of the data packet received by the third node; or, when the third node is a wireless backhaul node and the third status report includes information indicating a transmission status of a downlink data packet sent by the third node, the identifier of the third node is used to indicate that the information indicating the transmission status of the downlink data packet included in the third status report is the information indicating the transmission status of the downlink data packet sent by the third node.

In a possible implementation manner, the third node is a wireless backhaul node, and the processing unit is further configured to receive, by using the communication unit, a fourth status report from the third node, where the fourth status report includes information indicating a reception status of a data packet received by a terminal served by the third node from the third node; the processing unit is further configured to send, by using the communication unit, a fifth message to the centralized unit according to the fourth status report, where the fifth message includes information indicating a reception status of a data packet received by the terminal served by the third node from the third node.

In a possible implementation manner, the fourth status report includes an identifier of the terminal served by the third node, where the identifier of the terminal served by the third node is used to indicate that the information of the reception state of the data packet included in the fourth status report is the information of the reception state of the data packet received by the terminal served by the third node; or, the fourth status report includes an identifier of the terminal served by the third node and an identifier of at least one radio bearer of the terminal served by the third node, where the identifier of the terminal served by the third node and the identifier of the at least one radio bearer of the terminal served by the third node are used to indicate that the information of the reception state of the data packet included in the fourth status report is the information of the reception state of the data packet received by the terminal served by the third node through the at least one radio bearer.

In an eleventh aspect, a communication method is provided, which is applied to a second node, where the second node includes a centralized unit and a distributed unit, and the method includes: receiving, by the distributed unit, a sixth status report; the sixth status report is a status report which is sent to the second node by the node between the third node and the second node and is used for converting the information in the third status report into the information which can be identified by the second node; the distributed unit sending a fourth message to the centralized unit according to the sixth status report; in a case where the third node is a terminal, the sixth status report includes information indicating a reception status of a packet received by the third node from the first node, and the fourth message includes information indicating a reception status of a packet received by the third node from the first node; or, in a case that the third node is a wireless backhaul node, the sixth status report includes information indicating a reception status of a data packet received by the third node from the first node, and the fourth message includes information indicating a reception status of a data packet received by the third node from the first node; or, in a case that the third node is a wireless backhaul node, the sixth status report includes information for indicating a sending status of a downlink data packet sent by the third node, and the fourth message includes information for indicating a sending status of a downlink data packet sent by the third node; the third node is a node switched from the first node to the fourth node, the first node is a node providing wireless access service for the third node before the third node is switched, the second node is a host node of the first node, the first node and/or the fourth node are wireless backhaul nodes, and the wireless backhaul nodes are used for providing wireless backhaul service for nodes wirelessly accessing the wireless backhaul nodes; the first node to the fourth node are all nodes in wireless relay communication. By the method provided by the aspect, the centralized unit of the second node can know the downlink data packet receiving/sending state of the third node, so that the centralized unit of the second node can continue to send the data packet which is not successfully received by the third node or the terminal of the third node to the third node after the third node is switched.

In a possible implementation manner, the sixth status report includes an identifier of the third node; when the third node is a terminal, the identifier of the third node is used to indicate that the information of the reception status of the data packet included in the sixth status report is the information of the reception status of the data packet received by the third node; or, in a case that the third node is a wireless backhaul node and the sixth status report includes information indicating a reception status of a data packet received by the third node from the first node, the information indicating the reception status of the data packet included in the sixth status report is information indicating a reception status of the data packet received by the third node; or, when the third node is a wireless backhaul node and the sixth status report includes information indicating a transmission status of a downlink data packet sent by the third node, the identifier of the third node is used to indicate that the information indicating the transmission status of the downlink data packet included in the sixth status report is the information indicating the transmission status of the downlink data packet sent by the third node. By the possible method, the distributed unit of the second node can know that the information contained in the sixth status report is the information of the receiving status of the downlink data packet received by the third node, or the information of the sending status of the downlink data packet sent by the third node.

In one possible implementation, the third node is a wireless backhaul node, and the method further includes: the distributed unit receives a seventh status report, wherein the seventh status report is a status report which is sent to the second node by a node between the third node and the second node and converts information in a fourth status report into information which can be identified by the second node, and the fourth status report comprises information used for indicating the receiving status of a data packet received by a terminal served by the third node from the third node; and the distributed unit sends a fifth message to the centralized unit according to the seventh status report, wherein the fifth message comprises information for indicating the receiving status of the data packet received by the terminal served by the third node from the third node. By the possible method, in a scenario where the second node sends the downlink data packet to the third node through the at least one intermediate node, the distributed unit of the second node can correctly parse the information in the seventh status report, so as to generate a fifth message, and notify the centralized unit of the second node of the data receiving status of the third node service terminal.

In a possible implementation manner, the seventh status report includes an identifier of the terminal served by the third node, where the identifier of the terminal served by the third node is used to indicate that the information of the reception status of the data packet included in the seventh status report is the information of the reception status of the data packet received by the terminal served by the third node; or, the seventh status report includes an identifier of the terminal served by the third node and an identifier of at least one radio bearer of the terminal served by the third node, where the identifier of the terminal served by the third node and the identifier of the at least one radio bearer of the terminal served by the third node are used to indicate that the information of the reception state of the data packet included in the seventh status report is the information of the reception state of the data packet received by the terminal served by the third node through the at least one radio bearer. By the possible method, the distributed unit of the second node can learn that the seventh status report contains the information of the receiving status of the downlink data packet received by the terminal served by the third node, or the information of the receiving status of the downlink data packet received by the terminal served by the third node through at least one radio bearer.

In a twelfth aspect, there is provided a communication apparatus comprising a centralized unit and a distributed unit, the distributed unit comprising: a communication unit and a processing unit; the processing unit is configured to receive a sixth status report with the communication unit; the sixth status report is a status report which is transmitted to the communication device by the node between the third node and the communication device and is converted into information which can be identified by the communication device; the processing unit is further configured to send a fourth message to the centralized unit using the communication unit according to the sixth status report; in a case where the third node is a terminal, the sixth status report includes information indicating a reception status of a packet received by the third node from the first node, and the fourth message includes information indicating a reception status of a packet received by the third node from the first node; or, in a case that the third node is a wireless backhaul node, the sixth status report includes information indicating a reception status of a data packet received by the third node from the first node, and the fourth message includes information indicating a reception status of a data packet received by the third node from the first node; or, in a case that the third node is a wireless backhaul node, the sixth status report includes information for indicating a sending status of a downlink data packet sent by the third node, and the fourth message includes information for indicating a sending status of a downlink data packet sent by the third node; the third node is a node that is handed over from the first node to the fourth node, the first node is a node that provides wireless access service for the third node before the third node is handed over, the communication device is a host node of the first node, the first node and/or the fourth node are wireless backhaul nodes, and the wireless backhaul nodes are used for providing wireless backhaul service for nodes that wirelessly access the wireless backhaul nodes; the first node to the fourth node are all nodes in wireless relay communication.

In a possible implementation manner, the sixth status report includes an identifier of the third node; when the third node is a terminal, the identifier of the third node is used to indicate that the information of the reception status of the data packet included in the sixth status report is the information of the reception status of the data packet received by the third node; or, in a case that the third node is a wireless backhaul node and the sixth status report includes information indicating a reception status of a data packet received by the third node from the first node, the information indicating the reception status of the data packet included in the sixth status report is information indicating a reception status of the data packet received by the third node; or, when the third node is a wireless backhaul node and the sixth status report includes information indicating a transmission status of a downlink data packet sent by the third node, the identifier of the third node is used to indicate that the information indicating the transmission status of the downlink data packet included in the sixth status report is the information indicating the transmission status of the downlink data packet sent by the third node.

In one possible implementation, the third node is a wireless backhaul node, and the method further includes: the processing unit is further configured to receive a seventh status report by using the communication unit, where the seventh status report is a status report that a node between the third node and the communication device converts information in a fourth status report into information recognizable by the communication device and sends the information to the communication device, and the fourth status report includes information indicating a reception status of a packet received by a terminal served by the third node from the third node; the processing unit is further configured to send, by using the communication unit, a fifth message to the centralized unit according to the seventh status report, where the fifth message includes information indicating a reception status of a data packet received by the terminal served by the third node from the third node.

In a possible implementation manner, the seventh status report includes an identifier of the terminal served by the third node, where the identifier of the terminal served by the third node is used to indicate that the information of the reception status of the data packet included in the seventh status report is the information of the reception status of the data packet received by the terminal served by the third node; or, the seventh status report includes an identifier of the terminal served by the third node and an identifier of at least one radio bearer of the terminal served by the third node, where the identifier of the terminal served by the third node and the identifier of the at least one radio bearer of the terminal served by the third node are used to indicate that the information of the reception state of the data packet included in the seventh status report is the information of the reception state of the data packet received by the terminal served by the third node through the at least one radio bearer.

In a thirteenth aspect, a method for transmitting a data packet is provided, including: a first node receives a plurality of data packets with the same RLC SN through a plurality of paths, wherein the first node is a node in wireless relay communication; if the data packet received from the first path in the multiple paths is the RLC SDU, the first node sends the RLC SDU to a next hop node of the first node; or a first node receives data packets with the same RLC SN through a plurality of paths, wherein the first node is a node in wireless relay communication; if all the RLC SDU segments received from the multiple paths are RLC SDU segments and the RLC SDU segments capable of recovering the RLC SDU exist in the RLC SDU segments received from the multiple paths, the first node sends the RLC SDU segments capable of recovering the RLC SDU to a next hop node of the first node, or the first node recombines the RLC SDU segments received from the multiple paths and sends the RLC SDU obtained through recombination to the next hop node of the first node; or a first node receives data packets with the same RLC SN through a plurality of paths, wherein the first node is a node in wireless relay communication; and if all the received RLC SDUs from the multiple paths are RLC SDU segments and the RLC SDUs cannot be recovered by the RLC SDU segments received from the multiple paths, the first node sends the RLC SDU segments received on one of the multiple paths to a next hop node of the first node. In the method provided in the thirteenth aspect, when the Adapt layer is located between the MAC layer and the RLC layer and the end-to-end ARQ mode is adopted between the terminal and the host node, the data packet may be repeatedly detected by an actual aggregation node of the data packet, so that the repeated data packet is prevented from being transmitted between two nodes having only one path, and unnecessary transmission resource overhead is avoided.

In one possible implementation, the method further includes: the first node deletes a data packet, which is other than the data packet transmitted to the next hop node of the first node and is the same as the SN of the data packet transmitted to the next hop node of the first node. In this possible implementation, useless data packets can be deleted, so that the storage space of the first node is released.

In a fourteenth aspect, a communication apparatus is provided, including: a communication unit and a processing unit; the processing unit is used for receiving a plurality of data packets with the same RLC SN through a plurality of paths by using the communication unit, and the communication device is a node in wireless relay communication; if the data packet received from the first path of the multiple paths is an RLC SDU, the processing unit is further configured to send the RLC SDU to a next hop node of the communication device by using the communication unit; or, the processing unit is configured to receive data packets with the same RLC SN through multiple paths by using the communication unit, and the communication device is a node in wireless relay communication; if all the RLC SDU segments received from the plurality of paths are RLC SDU segments and there is an RLC SDU segment capable of recovering the RLC SDU in the RLC SDU segments received from the plurality of paths, the processing unit is further configured to transmit the RLC SDU segment capable of recovering the RLC SDU to a next hop node of the communication apparatus by using the communication unit, or the processing unit is further configured to reassemble the RLC SDU segments received from the plurality of paths by using the communication unit and transmit the reassembled RLC SDU to the next hop node of the communication apparatus; or, the processing unit is configured to receive data packets with the same RLC SN through multiple paths by using the communication unit, and the communication device is a node in wireless relay communication; if all the received segments of the RLC SDU from the plurality of paths are RLC SDU segments and the RLC SDU segments received from the plurality of paths cannot be recovered, the processing unit is further configured to send the RLC SDU segments received on one of the plurality of paths to a next hop node of the communication device by using the communication unit.

In a possible implementation manner, the processing unit is further configured to delete, by the communication unit, a data packet that is other than the data packet transmitted to the next hop node of the communication device and that has the same SN as the data packet transmitted to the next hop node of the communication device.

In a fifteenth aspect, a communication device is provided, comprising: a memory, a processor, at least one communication interface, and a communication bus; the memory is used for storing computer-executable instructions, the processor, the memory and the at least one communication interface are connected through a communication bus, and the processor executes the computer-executable instructions stored by the memory to enable the communication device to implement any one of the methods provided by the first or thirteenth aspects. The device may be the first node, or a component or a device in the first node, and may also be a system chip applied to the first node, and the like.

In a sixteenth aspect, there is provided a communication apparatus comprising: a memory, a processor, at least one communication interface, and a communication bus; the memory is used for storing computer-executable instructions, the processor, the memory and the at least one communication interface are connected through a communication bus, and the processor executes the computer-executable instructions stored by the memory to enable the communication device to implement any one of the methods provided by the fifth aspect, the seventh aspect, the ninth aspect or the eleventh aspect. The device may be in the form of a chip product. The device may be the second node, or a component or a device in the second node, or may be a system chip applied to the second node, or the like.

In a seventeenth aspect, a communication device is provided, comprising: a memory, a processor, at least one communication interface, and a communication bus; the memory is used for storing computer-executable instructions, the processor, the memory and the at least one communication interface are connected through a communication bus, and the processor executes the computer-executable instructions stored by the memory to enable the communication device to realize any one of the methods provided by the third aspect. The device may be in the form of a chip product. The device may be the third node, or a component or a device in the third node, or may be a system chip applied to the third node, or the like.

In an eighteenth aspect, there is provided a computer-readable storage medium comprising instructions which, when run on a computer, cause the computer to perform any one of the methods provided in the first, third, fifth, seventh, ninth, eleventh or thirteenth aspects.

A nineteenth aspect provides a computer program product comprising instructions which, when run on a computer, cause the computer to perform any one of the methods provided by the first, third, fifth, seventh, ninth, eleventh or thirteenth aspects.

In a twentieth aspect, a communication system is provided, comprising a first node and a third node, wherein the first node is configured to implement any one of the methods provided in the first aspect, and the third node is configured to implement any one of the methods provided in the third aspect.

For technical effects brought by any design manner of the second aspect, the fourth aspect, the sixth aspect, the eighth aspect, the tenth aspect, the twelfth aspect, the fourteenth aspect to the twentieth aspect, reference may be made to technical effects brought by corresponding design manners of the first aspect, the third aspect, the fifth aspect, the seventh aspect, the ninth aspect, the eleventh aspect and the thirteenth aspect, and no further description is provided herein.

It should be noted that, all possible implementation manners of any one of the above aspects may be combined without departing from the scope of the claims.

Drawings

Fig. 1 is a schematic networking diagram of an IAB node according to an embodiment of the present application;

fig. 2 is a schematic hardware structure diagram of a network node according to an embodiment of the present disclosure;

fig. 3 is a schematic diagram of a relationship between nodes according to an embodiment of the present application;

fig. 4 to fig. 7 are schematic diagrams of application scenarios provided in the embodiments of the present application, respectively;

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

fig. 9 is a schematic diagram illustrating a corresponding relationship between RLC SNs according to an embodiment of the present application;

fig. 10 is a schematic diagram illustrating a correspondence relationship between RLC SNs according to an embodiment of the present application;

fig. 11 is an interaction flowchart of another communication method provided in an embodiment of the present application;

fig. 12 is an interaction flowchart of another communication method provided in an embodiment of the present application;

fig. 13 is a flowchart of a method for transmitting a data packet according to an embodiment of the present application;

fig. 14 is a schematic composition diagram of a network node according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Where in the description of the present application, "/" indicates an OR meaning, for example, A/B may indicate A or B, unless otherwise indicated. "and/or" herein is merely an association describing an associated object, and means that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. Also, in the description of the present application, "a plurality" means two or more than two unless otherwise specified. In addition, in order to facilitate clear description of technical solutions of the embodiments of the present application, in the embodiments of the present application, terms such as "first" and "second" are used to distinguish the same items or similar items having substantially the same functions and actions. Those skilled in the art will appreciate that the terms "first," "second," etc. do not denote any order or quantity, nor do the terms "first," "second," etc. denote any order or importance.

The technical scheme of the embodiment of the application can be applied to various communication systems. For example: orthogonal Frequency Division Multiple Access (OFDMA), single carrier frequency division multiple access (SC-FDMA), and other systems. The term "system" may be used interchangeably with "network". The OFDMA system may implement wireless technologies such as evolved universal radio access (E-UTRA), Ultra Mobile Broadband (UMB), and the like. E-UTRA is an evolved version of the Universal Mobile Telecommunications System (UMTS). The third generation partnership project (3rd generation partnership project, 3GPP) is using a new version of E-UTRA in Long Term Evolution (LTE) and various versions based on LTE evolution. The fifth generation (5th-generation, abbreviated as 5G) communication system and the New Radio (NR) are the next generation communication systems under study. In addition, the communication system can also be applied to future-oriented communication technologies, and the technical solutions provided by the embodiments of the present application are all applied.

The system architecture and the service scenario described in the embodiment of the present application are for more clearly illustrating the technical solution of the embodiment of the present application, and do not constitute a limitation on the technical solution provided in the embodiment of the present application. As can be known to those skilled in the art, with the evolution of network architecture and the emergence of new service scenarios, the technical solution provided in the embodiments of the present application is also applicable to similar technical problems. In the embodiment of the present application, the method provided is applied to an NR system or a 5G network as an example. It should be noted that the method provided in the embodiment of the present application may also be applied to other networks, for example, an Evolved Packet System (EPS) network (that is, a so-called fourth generation (4G) network). Correspondingly, when the method provided by the embodiment of the present application is applied to an EPS network, the network node executing the method provided by the embodiment of the present application may be replaced by a network node in the EPS network. For example, when the method provided in the embodiment of the present application is applied in a 5G network or an NR system, the wireless backhaul node in the following text may be a wireless backhaul node in the 5G network, and for example, the wireless backhaul node in the 5G network may be referred to as an IAB node, and of course, may have other names, which is not specifically limited in the embodiment of the present application. When the method provided by the embodiment of the present application is applied to an EPS network, the wireless backhaul node in the following description may be a wireless backhaul node in the EPS network, and for example, the wireless backhaul node in the EPS network may be referred to as a Relay Node (RN). The wireless backhaul node is configured to provide a wireless backhaul service for a node (e.g., a terminal) wirelessly accessing the wireless backhaul node, wherein the wireless backhaul service refers to a backhaul service provided through a wireless backhaul link.

The present application refers to a node supporting integrated access and backhaul as a wireless backhaul node, which may also be referred to as an RN or an IAB node (IAB node). The wireless backhaul node may have a role of a Mobile Terminal (MT) and a role of a Distributed Unit (DU), that is, the wireless backhaul node may include at least one MT unit, and the wireless backhaul node may establish a backhaul connection with at least one parent node of the wireless backhaul node via the at least one MT. The DU part of the IAB node may provide access services for the MT part of the terminal or other IAB node.

The network element to which the present application relates comprises a terminal and a wireless backhaul node (e.g., IAB node, hereinafter, host node). It should be noted that, in this embodiment, a terminal may also be referred to as a User Equipment (UE), an access terminal, a subscriber unit, a subscriber station, a mobile station, a remote terminal, a mobile device, a user terminal, a wireless communication device, a user agent, or a user equipment. The terminal may also be a Station (ST) in a Wireless Local Area Network (WLAN), which may be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA) device, a handheld device with a wireless communication function, a computing device, or other processing devices connected to a wireless modem, a vehicle-mounted device, a wearable device (also referred to as a wearable smart device). The terminal may also be a terminal in a next-generation communication system, for example, a terminal in 5G or a terminal in a Public Land Mobile Network (PLMN) for future evolution, a terminal in a New Radio (NR) communication system, and the like.

With the development of Virtual Reality (VR), Augmented Reality (AR), internet of things and other technologies, more and more terminals will be available in future networks, and the usage amount of network data will be increased continuously. In order to match the increasing number of terminals and the rapidly increasing network data usage in the market, higher demands are being made on the capacity of 5G networks. In a hot spot area, in order to meet the requirement of 5G ultrahigh capacity, networking by using high-frequency small stations is more popular. The high-frequency carrier wave has poor propagation characteristics, serious shielding attenuation and low coverage range, so a large number of densely deployed small stations are required in a hot spot area. These small stations may be IAB nodes.

In order to design a flexible and convenient access and backhaul scheme, an Access Link (AL) and a Backhaul Link (BL) in an IAB scene both adopt a wireless transmission scheme.

In the IAB network, an IAB node may provide a wireless access service for a terminal, and is connected to a host node (donor node) through a wireless backhaul link to transmit traffic data of a user. Illustratively, the host node may be a host base station. The donor node may be referred to in 5G networks as an IAB donor (IAB donor) or DgNB (i.e., donor gdobad). The host node may be a complete entity, or may be in a form of separating a CU and a DU, the CU of the host node is herein abbreviated as a Donor-CU (also abbreviated as CU), and the DU of the host node is herein abbreviated as a Donor-DU, that is, the host node is composed of a Donor-CU and a Donor-DU. The Donor-CU has the functions of an SDAP (Service Data Adaptation Protocol) layer and a PDCP (packet Data Protocol) layer on a user plane, and has the functions of an RRC (radio resource control) layer and the PDCP layer on a control plane; the Donor-DU has functions of an RLC (radio link control) layer, a MAC (medium access control) layer, and a PHY (Physical) layer. Illustratively, the Donor-CU can also be a separate User Plane (UP) and Control Plane (CP) form, i.e., consist of a CU-CP and a CU-UP. The IAB node is connected to a core network through a wired link via a host node (for example, in an independent networking 5G architecture, the IAB node is connected to a core network (5G core, abbreviated as 5GC) of the 5G network through a wired link via a host node, in a non-independent networking 5G architecture, the IAB node is connected to an Evolved Packet Core (EPC) through an eNB (evolved nodeb) at a Control Plane (CP), and is connected to the EPC through the host node and the eNB at a User Plane (UP).

In order to ensure the reliability of service transmission, the IAB network supports multi-hop IAB node and multi-connection IAB node networking, and therefore, multiple transmission paths may exist between the terminal and the host node. On one path, there is a certain hierarchical relationship between IAB nodes, and between an IAB node and a host node serving the IAB node, each IAB node regards a node providing backhaul service for it as a parent node, and accordingly, each IAB node can be regarded as a child node of its parent node.

For example, referring to fig. 1, a parent node of the IAB node 1 is a host node, the IAB node 1 is a parent node of the IAB node 2 and the IAB node 3, the IAB node 2 and the IAB node 3 are both parent nodes of the IAB node 4, and the parent node of the IAB node 5 is the IAB node 3. An uplink data packet of the terminal may be transmitted to the host node through one or more IAB nodes, and then sent to the mobile gateway device (e.g., a User Plane Function (UPF) network element in a 5G network) by the host node, and a downlink data packet is received from the mobile gateway device by the host node, and then sent to the terminal through one or more IAB nodes. There are two available paths for packet transmission between terminal 1 and the host node, which are: terminal 1 → IAB node 4 → IAB node 3 → IAB node 1 → donor node, terminal 1 → IAB node 4 → IAB node 2 → IAB node 1 → donor node. There are three available paths for packet transmission between the terminal 2 and the host node, which are: terminal 2 → IAB node 4 → IAB node 3 → IAB node 1 → home node, terminal 2 → IAB node 4 → IAB node 2 → IAB node 1 → home node, terminal 2 → IAB node 5 → IAB node 2 → IAB node 1 → home node.

For example, the IAB node may be a Customer Premises Equipment (CPE), a home gateway (RG), or the like. The method provided by the embodiment of the application can also be applied to a home access scene.

The above-mentioned IAB networking scenario is only exemplary, and in an IAB scenario combining multi-hop and multi-connection, there are still more other possibilities in the IAB networking scenario, for example, a host node and an IAB node under another host node form a dual connection to serve a terminal, and the like, which are not listed here.

Currently, the protocol architecture of the user plane of the IAB node is divided into two major categories, which are group1 and group 2. group1 is the IAB architecture for layer 2. group2 is the IAB architecture for layer 3. One protocol architecture in group1 is 1a, which has the following features: a PDCP layer which is equivalent to the terminal and is positioned on a host node or a Donor-CU; the IAB node executes the forwarding of the service data of the terminal in a radio link control (RLC for short) and a following protocol layer, namely a data packet forwarded by the IAB node is a PDCP PDU of the terminal; an adaptation layer (which may be referred to as an Adapt layer for short) is introduced on a backhaul link of the IAB node (for the role of the Adapt layer, see the description of the relevant part below).

In the protocol architecture, the Adapt layer may be above the RLC layer or between a Medium Access Control (MAC) layer and the RLC layer, and the terminal may perform data transmission with the host node in any one of the following manners one to three.

In the first mode, a hop-by-hop automatic repeat-request (ARQ) mode (hop-by-hop ARQ) is adopted, in which case the Adapt layer may be above the RLC layer or between the MAC layer and the RLC layer.

In the second mode, an end-to-end ARQ mode (end-to-end ARQ) is adopted, in which case the Adapt layer may be between the MAC layer and the RLC layer.

And in a third mode, an end-to-end ARQ mode is adopted between the IAB node providing the wireless access service for the terminal and the host node, and in this case, the Adapt layer can be between the MAC layer and the RLC layer.

The end-to-end ARQ mode means that an ARQ mode is adopted between two end nodes. In this case, ARQ-related functions are configured on the RLC entities of both end nodes. The intermediate nodes do not need to configure the ARQ functionality. However, the RLC layer of the intermediate node may have a segmentation (segmentation) function and/or a re-segmentation (re-segmentation) function, and the intermediate node may feed back the received packet as a receiving node and retransmit an unacknowledged packet as a transmitting node. Wherein segmentation is for one complete RLC SDU and re-segmentation is for one RLC SDU segment. Taking uplink transmission as an example, a terminal sends a data packet to a host node through an IAB node, the host node feeds back an Acknowledgement (ACK) message to the IAB node when the host node correctly receives the data packet, and feeds back a non-acknowledgement (NACK) message to the IAB node when the host node does not correctly receive the data packet, and the IAB node only forwards the messages. When the host node feeds back the NACK message, the terminal will resend the data packet to the host node through the IAB node.

The hop-by-hop ARQ mode means that the ARQ mode is adopted between any two adjacent nodes. In this case, each node in a path is configured with an ARQ function, that is, the RLC layer of the intermediate node has a segmentation and/or re-segmentation function, and also has an ARQ related function, and the intermediate node not only can forward a packet, but also can feed back whether the packet is correctly received to the node that sent the packet (i.e., the previous hop node of the intermediate node).

In order to better understand the method described below, a portion of the protocol layers mentioned below are introduced here in a unified way.

(1) Adapt layer

The Adapt layer has at least one of the following capabilities: the method comprises the steps of adding routing information which can be identified by a wireless backhaul node to a data packet, performing routing selection based on the routing information which can be identified by the wireless backhaul node, adding identification information which can be identified by the wireless backhaul node and is related to quality of service (QoS) requirements to the data packet, performing QoS mapping on a multi-segment link containing the wireless backhaul node to the data packet, adding data packet type indication information to the data packet, and sending flow control feedback information to a node with flow control capability. It should be noted that the name of the protocol layer with these capabilities is not necessarily the Adapt layer, and those skilled in the art can understand that the protocol layer with these capabilities can be understood as the Adapt layer in the embodiment of the present application.

The routing information that can be identified by the wireless backhaul node may be one or more of an identifier of the terminal, an identifier of an IAB node to which the terminal accesses, an identifier of a host node, an identifier of a Donor-DU, an identifier of a Donor-CU, an identifier of a transmission path, and the like.

The QoS mapping on the multi-segment link may be: performing mapping from the radio bearer of the terminal to the radio bearer or the RLC channel or the logical channel on the backhaul link based on the identifier of the radio bearer of the terminal carried by the data packet in the backhaul link; it is also possible to perform mapping from the radio bearer or RLC channel or logical channel of the previous-hop link to the radio bearer or RLC channel or logical channel of the next-hop link based on the correspondence between the radio bearer/RLC channel/logical channel of the previous-hop link and the next-hop link.

The packet type indication information may be used to indicate that the content encapsulated in the Adapt layer includes any one of the following types: user plane data of the terminal, Radio Resource Control (RRC) message of the terminal, RRC message of the IAB node, control layer application message (for example, F1application protocol (F1application protocol, abbreviated as F1AP) message) on an interface between the IAB node and a host node (or a Donor-CU or CU-CP), flow control feedback message generated by the IAB node, and the like.

The identification information related to the QoS requirement may be an identification (QFI) of a QoS flow of the terminal, an identification (data radio bearer, DRB for short) or Signaling Radio Bearer (SRB) of the terminal, a differential service code point (DSCP for short), and the like.

Illustratively, the node with flow control capability may be an upstream node that provides backhaul service for the IAB node, such as a host node, a Donor-DU, a Donor-CU, a parent node of the IAB node, and so on. The content of the flow control feedback information may include one or more of the following information: the buffer status and the load degree of the IAB node, the status of a certain link including the IAB node (such as link blocking (block) or link recovery (resume) or link quality information), the bandwidth and the transmission delay of a certain link including the IAB node, the packet sequence number lost by the IAB node, the packet sequence number successfully sent by the IAB node to the terminal or a child node thereof, and the like.

In addition, the function of the Adapt layer may also be extended by the function of any one layer (e.g., RLC layer, MAC layer, PDCP layer, etc.) or any plurality of layers included in the layer 2, without an additional protocol layer, as a possible case.

(2) Layer F1AP

The F1AP layer is used to carry control plane messages between DUs (possibly the denor-DU of the home node, and possibly also the DU part in the IAB node, i.e. the IAB-DU) and CUs (or CU-CP). The control plane messages include one or more of the following: messages related to interface management between the DU and the CU, messages related to configuration update of the DU and the CU, context configuration messages related to child nodes of the DU (including terminals and other IAB nodes, etc.), messages of RRC messages of the child nodes of the DU carried in a message container (message container), and the like. The specific position of the F1AP layer is not limited in the examples of the present application. It should be noted that the name of the protocol layer having these capabilities is not necessarily the F1AP layer, and those skilled in the art can understand that any protocol layer having these capabilities can be understood as the F1AP layer in the embodiment of the present application. The messages a node generates or sends at the F1AP protocol layer may be referred to as F1AP messages. It should be noted that, when a DU is described separately in this embodiment, the DU may be a dongle-DU of the host node, or may be a DU of the IAB node.

(3) H-RLC (high-RLC) layer and L-RLC (lower-RLC) layer

The H-RLC layer and the L-RLC layer are two layers obtained after dividing the function of the RLC layer. The RLC layer comprises an allocation sequence number, an ARQ function and a reassembling (reassembling) function in an Acknowledged Mode (AM), and the L-RLC layer comprises a segmentation function; or, the H-RLC layer comprises the function of allocating sequence numbers and ARQ, and the L-RLC layer comprises the function of segmenting and recombining.

The embodiment of the application provides a network node, which may specifically be any one of a first node to a sixth node in the following. Hardware architecture of network node referring to fig. 2, fig. 2 shows a hardware architecture of a network node 20, which includes at least one processor 201, a communication bus 202, a memory 203, and at least one communication interface 204.

The processor 201 may be a general processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more ics for controlling the execution of programs according to the present disclosure.

The communication bus 202 may include a path that conveys information between the aforementioned components.

The communication interface 204 may be any device, such as a transceiver, for communicating with other devices or communication networks, such as an ethernet, a Radio Access Network (RAN), a WLAN, etc.

The memory 203 may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a Random Access Memory (RAM) or other types of dynamic storage devices that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compact disc, laser disc, optical disc, digital versatile disc, blu-ray disc, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited to such. The memory may be self-contained and coupled to the processor via a bus. The memory may also be integral to the processor.

The memory 203 is used for storing application program codes for executing the scheme of the application, and the processor 201 controls the execution. The processor 201 is configured to execute the application program code stored in the memory 203, thereby implementing the method provided by the embodiment of the present application.

In particular implementations, processor 201 may include one or more CPUs such as CPU0 and CPU1 in fig. 2, for example, as one embodiment.

In particular implementations, network node 20 may include a plurality of processors, such as processor 201 and processor 208 in fig. 2, as an embodiment. Each of these processors may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. A processor herein may refer to one or more devices, circuits, and/or processing cores for processing data (e.g., computer program instructions).

In particular implementations, network node 20 may also include an output device 205 and an input device 206, as one embodiment.

In order to make the description below more clear, a part of the concepts mentioned in the embodiments of the present application are briefly introduced here.

Source host node: a node switches the previous host node.

And the target host node: a host node after a node switch.

And link: a path between two adjacent nodes in a path.

Last hop node of the node: refers to the node in the path containing the node that last received a packet before the node.

Next hop node of node: refers to the node in the path containing the node that first receives a packet after the node.

Last hop link of node: refers to the link between the node and the node's last hop node.

Next hop link of the node: refers to the link between the node and the node's next hop node.

RLC Sequence Number (SN): SN of RLC Service Data Unit (SDU).

The communication method provided by the embodiment of the application can be applied to an application scene that the third node is switched from the first node to the fourth node. The nodes involved in the embodiment of the present application include a first node to a sixth node, and referring to fig. 3, the third node is a node that is switched from the first node to the fourth node; the first node is a node which provides wireless access service for the third node before the third node is switched; the fourth node is a node which provides wireless access service for the third node after the third node is switched; the fifth node is a node providing wireless access service for the first node; the second node is a host node of the first node; the sixth node is a host node of the fourth node. The first node and/or the fourth node is a wireless backhaul node, and the third node is a terminal or a wireless backhaul node. The first node to the sixth node are all nodes in wireless relay communication.

The above node names are merely for convenience of description of the embodiments of the present application. It is to be understood that when the second node is a node providing a wireless access service to the first node, the fifth node and the second node are the same node; when the host node of the first node and the host node of the fourth node are the same node, the second node and the sixth node are the same node; there may be other nodes between the fifth node and the second node and between the fourth node and the sixth node.

For example, the communication method provided by the embodiment of the present application may be applied to an application scenario as shown in fig. 4 or fig. 5, in which case, the third node is a terminal, the first node is an IAB node 2, the fourth node is an IAB node 3, and the second node is a host node 1. The communication method provided in the embodiment of the present application may also be applied to an application scenario as shown in fig. 6 or fig. 7, where in this case, the third node is an IAB node 4, the first node is an IAB node 2, the fourth node is an IAB node 3, and the second node is a host node 1.

The following specifically describes the communication method provided in the embodiments of the present application by way of the first embodiment and the second embodiment, respectively. Before the third node is switched from the first node to the fourth node, the second node may learn the status of the transmitted data packet (for example, whether the transmission is successful, whether the reception is successful, whether the transmission is successful, etc.) through a manner in which the first node transmits a status report (see the description of the first part of the embodiment) or a manner in which the third node transmits a status report (see the description of the second part of the embodiment), so that the third node continues to perform operations such as transmission (including retransmission) of the data packet after being switched to the fourth node.

Illustratively, the receiving status of the data packet in the embodiment of the present application is successful receiving the data packet or unsuccessful receiving the data packet. The transmission status of the data packet is that the data packet is transmitted or not transmitted, or the transmission status of the data packet is that the data packet is successfully transmitted (i.e. transmitted and the data packet is successfully received by the receiving end) or not successfully transmitted (i.e. transmitted and the data packet is not successfully received by the receiving end).

Example one

An embodiment of the present application provides a communication method, as shown in fig. 8, including:

801. and when the second node determines that the third node needs to be switched from the first node to the fourth node, the second node sends first indication information to the first node and/or sends a switching command to the third node. For the handover command, the second node may first send the handover command to the first node, and the handover command is forwarded to the third node by the first node. Accordingly, the first node receives the first indication information and/or the handover command from the second node.

The first indication information is used for indicating the first node to stop sending the data packet to the third node, and the switching command is used for switching the third node from the first node to the fourth node. The handover command may be an RRC message, such as an RRC reconfiguration message.

It is understood that the first node receives the first indication information from the second node when the second node transmits the first indication information to the first node, receives the handover command from the second node when the second node transmits the handover command to the first node, and receives the first indication information and the handover command from the second node when the second node transmits the first indication information and the handover command to the first node.

In a possible implementation manner of step 801, the second node may receive a measurement report sent by the third node, and determine that the third node needs to be switched from the first node to the fourth node according to the measurement report. For example, the measurement report may include signal strengths of reference signals of different cells measured by the third node, and the second node determines that the third node is required to be handed over from the first node to the fourth node when it is determined from the measurement report that the signal strength of the reference signal of the cell covered by the first node is smaller than the first threshold and the signal strength of the reference signal of the cell covered by the fourth node is larger than the second threshold. The first threshold and the second threshold may be the same or different, and the specific value may be determined according to an actual application scenario.

In another possible implementation manner of step 801, the second node may determine that the third node needs to be switched from the first node to the fourth node when it is determined that one or more links in the path between the third node and the second node are broken or congested.

802. The first node transmits a first status report to the second node, the first status report including information indicating a transmission status of a packet transmitted by the first node to the third node. Correspondingly, the second node receives the first status report from the first node, and determines the sending state of the data packet sent by the first node to the third node according to the first status report.

The first status report may be an Adapt layer status report or an RLC layer status report. Optionally, the data packet sent by the first node to the third node is an RLC SDU segment (segment) or an RLC SDU, and the first status report includes information indicating a transmission status of the RLC SDU segment or the RLC SDU sent by the first node to the third node.

Optionally, when the first status report is a status report of the Adapt layer, the first status report uses the PDCP SN to indicate the transmission status of the PDCP PDU sent by the first node to the third node.

Optionally, the first status report includes an identifier of the first node, where the identifier of the first node is used to indicate that the information of the transmission state of the data packet included in the first status report is the information of the transmission state of the data packet transmitted by the first node.

Optionally, the first status report further includes an identifier of a third node, where the identifier of the third node is used to indicate that the information of the transmission state of the data packet included in the first status report is the information of the transmission state of the data packet transmitted to the third node; or, the first status report further includes an identifier of the third node and an identifier of at least one radio bearer of the third node, where the identifier of the third node and the identifier of the at least one radio bearer are used to indicate that the information of the transmission status of the data packet included in the first status report is the information of the transmission status of the data packet transmitted to the third node through the at least one radio bearer.

In this embodiment, the identifier of the node (e.g., the terminal or the wireless backhaul node (e.g., the MT part of the IAB node)) may be a cell radio network temporary identifier (C-RNTI) of the node, an international mobile subscriber identity number (IMSI), a Temporary Mobile Subscriber Identity (TMSI), a unique identifier allocated by the host node/node-CU for the node within a service range of the host node/node-CU, and the like. The identifier of the radio bearer is used to identify a Data Radio Bearer (DRB) and/or a Signaling Radio Bearer (SRB) of the node. In a possible manner, both the identifier of the node and the bearer identifier of the node may be represented by a Tunnel Endpoint Identifier (TEID) of a GPRS tunneling protocol (GTP for short) corresponding to a radio bearer of the node, where the GTP tunnel may be a transmission channel between a host node/node-CU and a DU (e.g., a DU portion of an IAB node providing an access service, or a don-DU) providing an access service for the node.

When the third node is a terminal, step 802 may be implemented in the following manner 1 or manner 2, and when the third node is a wireless backhaul node, step 802 may be implemented in the following manner 2.

In the mode 1, the first node sends the first state report to the second node end to end.

In this case, a node between the first node and the second node may forward the first status report to the second node.

When step 802 is implemented in manner 1, if the second node includes a donor-CU and a donor-DU, the method may further include:

11) receiving a first status report from the first node by the donor-DU;

12) and the denor-DU sends a third message to the denor-CU according to the first state report, wherein the third message comprises information used for indicating the sending state of the data packet sent by the first node to the third node.

Step 12) in specific implementation, the donor-DU may convert the RLC SN of the data packet that has been sent (or that has been successfully sent) indicated therein into the PDCP SN carried in the corresponding PDCP PDU according to the first status report, and generate a third message according to the converted corresponding PDCP SN, and send the third message to the donor-CU.

And 2, the first node sends the first state report to the second node hop by hop.

In this case, the step 802 includes, in a specific implementation: the first node sends a first status report to the second node through the node between the first node and the second node, and the node between the first node and the second node is used for converting the information in the status report received from the previous hop node into the information which can be identified by the next hop node, placing the information in the status report and sending the information to the next hop node.

In the method 2, a node between the first node and the second node may generate a status report to be sent to the next hop node according to the correspondence between the RLC SNs in the previous hop link and the next hop link and the RLC SN in the status report sent by the previous hop node, and place the status report in the status report and send the status report to the next hop node. For example, one node may replace the RLC SN in the received status report with the RLC SN corresponding to the RLC SN on the next-hop link, thereby converting into the status report to be sent to the next-hop node.

When step 802 is implemented by means of 2, if the second node includes a donor-CU and a donor-DU, the method may further include:

21) and the donor-DU receives a fifth status report, wherein the fifth status report is a status report which is sent to the second node by the node between the first node and the second node and is used for converting the information in the first status report into the information which can be identified by the second node.

22) And the denor-DU sends a third message to the denor-CU according to the fifth status report, wherein the third message comprises information used for indicating the sending status of the data packet sent by the first node to the third node.

Step 22) in specific implementation, the donor-DU may convert the RLC SN of the data packet that has been sent (or that has been successfully sent) indicated therein into the PDCP SN carried in the corresponding PDCP PDU according to the fifth status report, and generate a third message according to the converted corresponding PDCP SN, and send the third message to the donor-CU.

The fifth status report may include an identifier of the first node, where the identifier of the first node is used to indicate that the information of the transmission status of the data packet included in the fifth status report is the information of the transmission status of the data packet transmitted by the first node.

The fifth status report may further include an identifier of the third node, where the identifier of the third node is used to indicate that the information of the transmission status of the data packet included in the fifth status report is the information of the transmission status of the data packet transmitted to the third node; or, the fifth status report further includes an identifier of the third node and an identifier of the at least one radio bearer, where the identifier of the third node and the identifier of the at least one radio bearer are used to indicate that the information of the transmission status of the data packet included in the fifth status report is the information of the transmission status of the data packet transmitted to the third node through the at least one radio bearer.

For example, the third message in the above embodiment may be a Downlink Data Delivery Status (DDDS) report.

Optionally, when step 802 is implemented by using the method 2, the status report between any two adjacent nodes in the path between the first node and the previous-hop node of the second node includes second indication information, and the second indication information included in one status report is used to indicate the node receiving the status report to convert the information in the status report into information that is recognizable by the next-hop node of the node receiving the status report, and send the information to the next-hop node.

In addition, when the second node includes a donor-CU and a donor-DU, the status report between the previous-hop node of the second node and the second node may also include second indication information, so that the donor-DU in the second node sends a third message to the donor-CU of the second node according to the second indication information.

For example, in a normal communication scenario (that is, when the third node does not perform handover, a communication scenario in which data transmission is performed normally between the second node and the third node), when a node between the first node and the second node receives a status report, the node between the first node and the second node may retransmit an incorrectly transmitted data packet to a node that sends the status report according to the status report, and the received status report is not converted and sent to a next hop node. Therefore, the status report in the normal communication scenario and the status report in the communication scenario of the third node performing the handover are distinguished by adding the second indication information to the status report. When the status report is an Adapt layer status report, the second indication information may be placed in the Adapt layer status report, or may be indicated by a message type of the Adapt layer status report.

Optionally, before step 802, the method may further include: 31) the first node generates a first status report. When the step 31) is specifically implemented, it may be implemented by the following manner (1) or manner (2).

In the method (1), the first node generates a first status report according to the transmitted data packet.

In this case, the transmission state of the packet is either the transmission of the packet or the non-transmission of the packet.

In the method (1), if an end-to-end ARQ mode is adopted between the third node and the second node, in one case, the first node may directly feed back information of the sending state of the RLC SDU segments to the second node, and in this case, when receiving the data packet sent by the second node, the first node does not perform reassembly of the RLC SDU segments, and directly sends the RLC SDU segments to the third node. In another case, the first node may feed back information of the sending state of the RLC SDU to the second node, and in this case, when receiving the data packet sent by the second node, the first node performs reassembly of RLC SDU segments and sends a complete RLC SDU to the third node.

In this case, the first status report may indicate the transmission or reception status of the data packet by the SN of the data packet. Illustratively, the first status report may include information of the largest RLC SN of a packet transmitted to the third node, and RLC SN information of packets not sent to the third node before this maximum RLC SN, and may further include RLC SN information of packets that the first node considers missing or that the third node has not received, if a packet not sent to the third node (or a packet that the first node considers missing or that the first node has not received) is an RLC SDU segment, the first status report further includes offset information of the segment relative to the original complete RLC SDU (i.e., SO start and SO end, SO start indicating the relative position of the first byte of the segment relative to the first byte of the original complete RLC SDU, and SO end indicating the relative position of the last byte of the segment relative to the first byte of the original complete RLC SDU).

In the mode (2), the first node generates a first status report according to the status report sent by the third node.

The mode (2) may include, when implemented:

41) the first node transmits a first message to the third node, the first message including information for instructing the third node to report a reception status of a data packet received from the first node. Accordingly, the third node receives the first message from the first node.

42) The third node transmits a second status report to the first node, the second status report including information indicating a reception status of a packet received by the third node from the first node. Accordingly, the first node receives a second status report from the third node.

43) The first node generates a first status report according to the second status report.

Wherein the first message may be an RLC status poll message, in which case, step 41) may be implemented by the AM RLC entity of the first node to send the first message to the third node. The second status report may be an RLC layer status report.

In this case, the sending state of the data packet sent by the first node to the third node refers to sending a successful data packet or not sending a successful data packet.

In this case, the first status report may indicate the transmission or reception status of the data packet by the SN of the data packet. For example, the first status report may include information that is greater than 1 of the maximum RLC SN of a data packet that has been successfully transmitted to the third node, and information of the RLC SN of a data packet that has not been successfully transmitted to the third node before the RLC SN corresponding to the information, and may further include information of the RLC SN of a data packet that the first node considers missing or that the third node has not successfully received, and if the data packet that has not been successfully transmitted to the third node (or a data packet that the first node considers missing or that the first node considers that the third node has not successfully received) is an RLC SDU segment, the first status report further includes offset value information of the segment with respect to the original complete RLC SDU.

When the first node sends the first status report to the second node end to end, step 43) may be implemented in the following manner 3 or manner 4, and when the first node sends the first status report to the second node hop by hop, step 43) may be implemented in the following manner 5.

In the mode 3, the first node generates a first status report according to the corresponding relation of the RLC SNs between the first link and the first path and the RLC SNs contained in the second status report; the first link is a link between the first node and the third node, and the first path is a path between the first node and the second node.

When step 43) is implemented by using the method 3, the third node is a terminal, and the first node may store a correspondence relationship between the first link and the RLC SN in the first path. Referring to fig. 9, the peer RLC layer between the terminal and the first node is a complete RLC layer, and between the first node and the second node, there is a peer H-RLC layer. The data packets with

RLC SNs

1, 2, and 3 on the link 1 are the data packets with

RLC SNs

5, 7, and 9 on the path 1, and the RLC SNs with

values

1, 2, and 3 on the link 1 have a mapping relation with the RLC SNs with

values

5, 7, and 9 on the path 1. In order to ensure that the second node can identify the information in the status report, when the first node includes the RLC SN with the value of 1, 2 or 3 in the status report received by the H-RLC layer, the first node replaces 1, 2 or 3 with 5, 7 or 9 correspondingly in the status report sent by the H-RLC layer to the second node.

Mode 4, the first node generates a first status report according to the corresponding relation between the RLC SN and the PDCP SN of the first link and the RLC SN included in the second status report; the first link is a link between the first node and the third node.

When step 43) is implemented by using the method 4, the third node is the terminal, the first status report is an Adapt layer status report, and the first node may store a correspondence between the RLC SN and the PDCP SN of the first link. The PDCP SN is a SN of a PDCP layer of the terminal.

In the mode 5, the first node generates a first status report according to the corresponding relation of the RLC SNs between the previous-hop link (marked as a first link) and the next-hop link (marked as a second link) and the RLC SNs contained in the second status report; the first link is a link between the first node and the third node, and the second link is a link between the first node and the fifth node.

Optionally, the first node may store a correspondence between RLC SNs of the previous-hop link and the next-hop link.

The RLC SN mapping relationship between the previous-hop link and the next-hop link in the embodiment of the present application can be understood with reference to fig. 10. Wherein, the data packets with

RLC SNs

1, 2 and 3 on the link 1 are the data packets with

RLC SNs

5, 7 and 9 on the link 2, and the RLC SNs with

values

1, 2 and 3 on the link 1 and the RLC SNs with

values

5, 7 and 9 on the link 2 have a mapping relationship. In order to ensure that the fifth node can identify the information in the status report, when the RLC SN with the value of 1, 2 or 3 is included in the status report received by the first node, the first node replaces 1, 2 or 3 with 5, 7 or 9 correspondingly in the status report sent to the fifth node.

According to the method provided by the embodiment of the application, the first node can send the first status report to the second node when receiving the first indication information and/or the switching command, so that the second node receives the sending status of the data packet sent by the second node to the third node as early as possible, thereby avoiding the overlong waiting time of the data packet which is not successfully received by the third node, and improving the communication efficiency of the network. Meanwhile, the problem of Hyper Frame Number (HFN) desynchronization between the second node and the third node due to a large gap generated by the PDCP SN in the PDCP PDU received by the third node can be avoided.

Optionally, the method further includes: and the first node sends the cached uplink data packet sent by the third node to the second node. The first node may continue to transmit the uplink data packet of the third node via its backhaul link, and the second node may count the reception status of the uplink data packet sent by the third node according to the uplink data packet forwarded by the first node. At present, a specific implementation scheme is not given in the prior art for how a third node processes an uplink data packet that has been sent by the third node in a handover process. The optional method provides a method for the first node to send the cached uplink data packet sent by the third node, and ensures the continuity of the uplink service, so that the third node does not need to resend the sent uplink data packet after switching, and the waste of air interface resources is avoided.

In the alternative method, the first node transmits the uplink data packet of the third node via its backhaul link, so that the second node continues to perform operations such as transmission (including retransmission) of the data packet.

Optionally, the method further includes: and the first node sends third indication information to the second node, wherein the third indication information is used for indicating that the first node has sent all uplink data packets which are sent by the buffered third node.

The third indication information may be included in the last uplink data packet, for example, the third indication information may be carried in a reserved field (reserved field) of RLC header information by using 1 bit, or may be carried in header information of an adaptation layer; the third indication may also be a separate data packet (adapt PDU or RLC PDU). The third indication information may also be referred to as an end mark (end marker). After receiving the third indication information, the second node may instruct the first node to release all contexts of the third node. When the third node is a wireless backhaul node, the second node may also instruct the first node to release the context of all terminals served by the third node.

Illustratively, when the host node of the first node (i.e., the second node) and the host node of the fourth node (i.e., the sixth node) are different nodes, after the handover, the second node needs to send an SN status transfer message to the sixth node, where the SN status transfer message is used to indicate, to the sixth node, the sending status of the downlink data packet sent by the second node to the third node and the sending status of the uplink data packet sent by the third node to the second node, so that after the handover, the second node sends, to the sixth node, the downlink data packet that the third node has not received successfully and the uplink data packet that the second node has not received successfully through an Xn interface (an interface between NR base stations, or an interface between CUs of different NR base stations), and then retransmits, by the sixth node, the downlink data packet that the third node has not received successfully through the fourth node, the sixth node retransmits the downlink data packet to the third node, and instructing the third node to retransmit the uplink data packet which is not successfully received by the second node to the second node.

When the second node and the sixth node are in a form of separating the donor-CU from the donor-DU, if the donor-DU of the sixth node providing backhaul connection for the fourth node and the donor-DU of the second node providing backhaul connection for the first node are the same donor-DU, the donor-DU may directly retransmit, by the fourth node, the downlink data packet that is not successfully received by the third node to the third node according to the received information on the transmission state of the downlink data packet that is transmitted from the second node to the third node, thereby preventing the downlink data packet that is not successfully received by the third node from being retransmitted between the donor-CU and the donor-DU many times in the process of switching the third node.

Example two

This embodiment provides a communication method, as shown in fig. 11, including:

1101. and when the second node determines that the third node needs to be switched from the first node to the fourth node, the second node sends a switching command to the third node. Accordingly, the third node receives a handover command for the third node to handover from the first node to the fourth node.

For example, in step 1101, in a specific implementation, a scenario in which the second node sends the handover command may refer to the description of the corresponding part in the foregoing embodiment, and is not described herein again.

Illustratively, the handover command may be an RRC reconfiguration message.

1102. The third node sends a third status report to the second node.

Wherein, in case that the third node is a terminal, the third status report includes information indicating a reception status of a packet received by the third node from the first node; alternatively, in case the third node is a wireless backhaul node, the third status report comprises: information for indicating a reception state of a packet received by the third node from the first node, or information for indicating a transmission state of a downlink packet transmitted by the third node.

For example, in a case that the third node is a wireless backhaul node, the downlink data packet sent by the third node may be a downlink data packet sent by the third node to a terminal served by the third node, and may also be a downlink data packet sent by the third node to a wireless backhaul node served by the third node. Optionally, when the terminal (or the wireless backhaul node) served by the third node transmits the data packet in the end-to-end ARQ mode with the second node, the third node is responsible for forwarding the data packet, and does not have an ARQ function, that is, the third node cannot obtain information of a reception state (i.e., whether the reception is successful) of the data packet received by the terminal or the IAB node served by the third node from the third node. Therefore, when the third node reports the information of the transmission status of the downlink data packet to the second node, the third node may inform the second node of the sequence number of the downlink data packet that the third node has already transmitted, so that the second node can determine which data packets need to be retransmitted, and the like.

In this embodiment, the terminal served by the third node may be a normal terminal, or may be an IAB node (for example, an MT part of the IAB node) whose role is a terminal. The data packet in this embodiment may be an RLC SDU segment, or an RLC SDU.

The third status report may be an RLC layer status report when the third node is a terminal, and the third status report may be an Adapt layer status report or an RLC layer status report when the third node is a wireless backhaul node.

The third status report may include an identification of the third node. When the third node is a terminal, the identifier of the third node is used for indicating that the information of the receiving state of the data packet contained in the third status report is the information of the receiving state of the data packet received by the third node; or, in a case that the third node is a wireless backhaul node and the third status report includes information indicating a reception status of a data packet received by the third node from the first node, the information indicating the reception status of the data packet included in the third status report is information indicating a reception status of the data packet received by the third node; or, when the third node is a wireless backhaul node and the third status report includes information indicating a transmission status of a downlink data packet transmitted by the third node, the identifier of the third node is used to indicate that the information indicating the transmission status of the downlink data packet included in the third status report is the information indicating the transmission status of the downlink data packet transmitted by the third node.

Under the condition that the third node is a wireless backhaul node and the third status report includes information for indicating the transmission status of a downlink data packet transmitted by the third node, the third status report may further include an identifier of a terminal served by the third node, and the information for indicating the transmission status of the data packet included in the third status report is information of the transmission status of the data packet transmitted to the terminal, where the third status report may include identifiers of one or more terminals; or, the third status report may further include an identifier of the terminal and an identifier of a radio bearer of the terminal, where the information indicating the transmission status of the data packet included in the third status report is information of the transmission status of the data packet transmitted to the terminal through the radio bearer of the terminal, and the third reporting status may include identifiers of one or more radio bearers of one terminal or identifiers of multiple radio bearers of multiple terminals.

In the third status report, the sending or receiving status of the data packet may be indicated by the SN of the data packet, and the SN of the data packet may specifically be the SN of the data packet in the RLC layer. For example, the third status report may include information of the maximum RLC SN of a transmitted (or received) data packet and information of the RLC SN of a data packet that is not transmitted (or not received) before the maximum RLC SN, and if the unsent (or not received) data packet is an RLC SDU segment, the third status report further includes offset value information of the segment relative to the original complete RLC SDU.

When the step 1102 is implemented specifically, the method 6 or the method 7 can be implemented.

And in the mode 6, the third node sends the third state report to the second node end to end.

In this case, a node between the third node and the second node may forward the third status report to the second node.

When step 1102 is implemented in manner 6, if the second node includes a donor-CU and a donor-DU, the method may further include:

51) the donor-DU receives a third status report from the third node.

52) The donor-DU sends a fourth message to the donor-CU according to the third status report.

Wherein, in case that the third node is a terminal, the third status report includes information indicating a reception status of a packet received by the third node from the first node, and the fourth message includes information indicating a reception status of a packet received by the third node from the first node; or, in case that the third node is a wireless backhaul node, the third status report includes information indicating a reception status of a data packet received by the third node from the first node, and the fourth message includes information indicating a reception status of a data packet received by the third node from the first node; or, in the case that the third node is a wireless backhaul node, the third status report includes information for indicating the transmission status of the downlink data packet sent by the third node, and the fourth message includes information for indicating the transmission status of the downlink data packet sent by the third node.

Step 52) in specific implementation, the donor-DU may convert the RLC SN of the data packet that has been sent (or that has been successfully sent) indicated therein into the PDCP SN carried in the corresponding PDCP PDU according to the third status report, and generate a fourth message according to the converted corresponding PDCP SN, and send the fourth message to the donor-CU.

And in the mode 7, the third node sends the third state report to the second node hop by hop.

In this case, the step 1102 may include, when implemented specifically: and the third node sends a third status report to the second node through the node between the third node and the second node, and the node between the third node and the second node is used for converting the information in the status report received from the previous hop node into the information which can be identified by the next hop node, placing the information in the status report and sending the information to the next hop node.

In the method 7, the node between the third node and the second node may generate a status report to be sent to the next hop node according to the correspondence between the RLC SNs in the previous hop link and the status report sent by the previous hop node, and place the status report in the status report to be sent to the next hop node. For example, one node may replace the RLC SN in the received status report with the RLC SN corresponding to the RLC SN on the next-hop link, thereby converting into the status report to be sent to the next-hop node.

The description of the correspondence between the RLC SNs of the previous-hop link and the next-hop link is referred to above and will not be described herein.

When step 1102 is implemented in manner 7, if the second node includes a donor-CU and a donor-DU, the method may further include:

61) the donor-DU receives the sixth status report; the sixth status report is a status report which is transmitted to the second node by the node between the third node and the second node by converting the information in the third status report into the information recognizable by the second node.

62) The donor-DU sends a fourth message to the donor-CU according to the sixth status report.

Step 62) in specific implementation, the donor-DU may convert the RLC SN of the data packet that has been sent (or that has been successfully sent) indicated therein into the PDCP SN carried in the corresponding PDCP PDU according to the sixth status report, and generate a fourth message according to the converted corresponding PDCP SN, and send the fourth message to the donor-CU.

Optionally, the sixth status report includes an identifier of the third node; when the third node is a terminal, the identifier of the third node is used to indicate that the information of the reception state of the data packet included in the sixth status report is the information of the reception state of the data packet received by the third node; or, in a case that the third node is a wireless backhaul node and the sixth status report includes information indicating a reception status of a packet received by the third node from the first node, the information indicating the reception status of the packet included in the sixth status report is information indicating a reception status of a packet received by the third node; or, when the third node is a wireless backhaul node and the sixth status report includes information indicating a transmission status of a downlink data packet transmitted by the third node, the identifier of the third node is used to indicate that the information indicating the transmission status of the downlink data packet included in the sixth status report is the information indicating the transmission status of the downlink data packet transmitted by the third node.

Wherein the information contained in the fourth message may be referred to above. The fourth message in the above embodiments may be a DDDS.

When step 1102 is implemented in the method 7, optionally, a status report between any two adjacent nodes in a path between the third node and the previous hop node of the second node includes fourth indication information, where the fourth indication information included in one status report is used to indicate a node receiving the status report to convert information in the status report into information that is recognizable by the next hop node of the node receiving the status report, and send the information to the next hop node.

Optionally, in a common communication scenario (that is, when the third node does not perform handover, a communication scenario in which data transmission is performed normally between the second node and the third node), when the node between the third node and the second node receives a status report, the node between the third node and the second node may retransmit an incorrectly transmitted data packet to the node that sends the status report according to the status report, and may not convert the received status report and send the received status report to the next hop node. Therefore, the fourth indication information is added to the status report to distinguish the status report in the normal communication scenario from the status report in the communication scenario in which the third node performs handover. When the status report is an Adapt layer status report, the fourth indication information may be located in the Adapt layer status report, or may be indicated by a message type of the Adapt layer status report. Optionally, in a case that the third node is a wireless backhaul node, the method further includes:

71) the third node sends a second message to the terminal served by the third node, the second message including information for instructing the terminal served by the third node to report a reception status of the data packet received from the third node. Accordingly, the terminal served by the third node receives the second message from the third node.

72) The terminals served by the third node transmit status reports to the third node, the status report of one terminal comprising information indicating the reception status of data packets received by the terminal from the third node. Accordingly, the third node receives a status report of the terminal served by the third node.

73) The third node sends a fourth status report to the second node according to the status report of the terminal served by the third node, the fourth status report including information indicating a reception status of a data packet received by the terminal served by the third node from the third node.

Wherein the second message may be an RLC status polling message, in which case, step 71) may be, in specific implementation, sending the second message to a terminal served by the third node by an AM RLC entity of the third node. The status report of the terminal may be an RLC layer status report, and the fourth status report may be an RLC layer status report or an Adapt layer status report.

The alternative method may enable the second node to more accurately determine whether a data packet transmission between the third node and a terminal it serves was successful. The optional method may be applied in a scenario where a hop-by-hop ARQ mode is adopted between the terminal and the second node, or an end-to-end ARQ mode is adopted between a node providing a wireless access service for the terminal and the second node. By the third node sending the fourth status report, the second node can be made aware of the latest information of the packet transmission status between the third node and the terminal.

Optionally, the fourth status report includes an identifier of the terminal served by the third node, where the identifier of the terminal served by the third node is used to indicate that the information of the reception state of the data packet included in the fourth status report is the information of the reception state of the data packet received by the terminal served by the third node; or the fourth status report includes the identifier of the terminal served by the third node and the identifier of the at least one radio bearer of the terminal served by the third node, and the identifier of the terminal served by the third node and the identifier of the at least one radio bearer of the terminal served by the third node are used to indicate that the information of the reception state of the data packet included in the fourth status report is the information of the reception state of the data packet received by the terminal served by the third node through the at least one radio bearer.

Step 73) can be realized by way of way 8 or way 9 when embodied.

And 8, the third node sends the fourth state report to the second node end to end.

In the embodiment, the mode 8 can be implemented by the following mode 1) or mode 2).

Mode 1), the third node generates a fourth status report according to the corresponding relation of the RLC SN between the third link and the second path and the RLC SN included in the status report of the terminal served by the third node, and sends the fourth status report to the second node.

Mode 2), the third node generates a fourth status report according to the corresponding relation between the RLC SN and the PDCP SN of the third link and the RLC SN included in the status report of the terminal served by the third node, and sends the fourth status report to the second node.

In the modes 1) and 2), the third link is a link between the third node and a terminal served by the third node, and the second path is a path between the third node and the second node.

The implementation manners of the manner 1) and the manner 2) are respectively similar to the implementation manners of the manner 3 and the manner 4 in the above embodiment, and may be understood by referring to the above specifically, and are not described again here.

In the mode 2), the sequence number of the data packet included in the fourth status report may be the PDCP SN.

When step 73) is implemented in the manner 8, if the second node includes a donor-CU and a donor-DU, the method may further include:

81) the donor-DU receives a fourth status report from the third node, the fourth status report including information indicating a reception status of a packet received by the terminal served by the third node from the third node.

82) And the donor-DU sends a fifth message to the donor-CU according to the fourth status report, wherein the fifth message comprises information used for indicating the receiving status of the data packet received by the terminal served by the third node from the third node.

Step 82), in specific implementation, the donor-DU may convert the RLC SN of the data packet that has been sent (or that has been successfully sent) indicated therein into the PDCP SN carried in the corresponding PDCP PDU according to the fourth status report, and generate a fifth message according to the converted corresponding PDCP SN, and send the fifth message to the donor-CU.

Optionally, when the sequence number of the data packet included in the fourth status report is the PDCP SN, the denor-DU may include the PDCP SN in the fourth status report in a fifth message and send the fifth message to the denor-CU.

And 9, the third node sends the fourth state report to the second node hop by hop.

The method 9 may include, in a specific implementation: the third node generates a fourth status report according to the corresponding relation of the RLC SNs between the third link and the fourth link and the RLC SNs contained in the status report of the terminal served by the third node, and sends the fourth status report to the second node through the node between the third node and the second node, the node between the third node and the second node is used for converting the information in the status report received from the previous hop node into the information which can be identified by the next hop node and sending the information to the next hop node, and the fourth link is the link between the third node and the first node.

The implementation manner of the mode 9 is similar to the implementation manner of the mode 5 in the above embodiment, and can be understood by specifically referring to the above, and is not described herein again.

When step 73) is implemented in the manner 9, if the second node includes a donor-CU and a donor-DU, the method may further include:

91) the donor-DU receives a seventh status report, wherein the seventh status report is a status report which is sent to the second node by a node between the third node and the second node by converting the information in the fourth status report into information which can be identified by the second node, and the fourth status report comprises information used for indicating the receiving status of a data packet which is received by a terminal served by the third node from the third node;

92) and the donor-DU sends a fifth message to the donor-CU according to the seventh status report, wherein the fifth message comprises information used for indicating the receiving status of the data packet received by the terminal served by the third node from the third node.

And step 92) in specific implementation, the donor-DU may convert the RLC SN of the data packet that has been sent (or that has been successfully sent) indicated therein into the PDCP SN carried in the corresponding PDCP PDU according to the seventh status report, and generate a fifth message according to the converted corresponding PDCP SN, and send the fifth message to the donor-CU.

Optionally, the seventh status report includes an identifier of the terminal served by the third node, where the identifier of the terminal served by the third node is used to indicate that the information of the reception state of the data packet included in the seventh status report is the information of the reception state of the data packet received by the terminal served by the third node; or the seventh status report includes the identifier of the terminal served by the third node and the identifier of the at least one radio bearer of the terminal served by the third node, and the identifier of the terminal served by the third node and the identifier of the at least one radio bearer of the terminal served by the third node are used to indicate that the information of the reception state of the data packet included in the seventh status report is the information of the reception state of the data packet received by the terminal served by the third node through the at least one radio bearer.

For example, the fifth message in the above embodiment may be a DDDS.

In the method provided by the embodiment of the application, the third node may send the third status report to the second node when receiving the handover command (i.e., not after the handover is completed), so that the second node receives the sending status or the receiving status of the data packet as early as possible, thereby avoiding the overlong waiting time for the data packet which is not successfully received or successfully sent, and improving the communication efficiency of the network. Meanwhile, the problem that the hyper frame number between the second node and the third node is out of step due to a larger gap (gap) generated by the PDCP SN of the PDCP PDU received by the third node can be avoided.

Illustratively, when the host node of the first node (i.e., the second node) and the host node of the fourth node (i.e., the sixth node) are different nodes, after the handover, the third node needs to send an SN status transfer message to the sixth node, where the SN status transfer message is used to indicate, to the sixth node, a receiving status of a data packet received by the third node from the first node or a sending status of a downlink data packet sent by the third node, so that after the handover, the second node sends, to the sixth node, the downlink data packet that the third node has not received successfully or has not sent via the Xn interface, and then the sixth node retransmits, to the third node, the downlink data packet that the third node has not received successfully or has not sent via the fourth node.

When the second node and the sixth node are in a form of separating the donor-CU and the donor-DU, if the donor-DU of the sixth node providing backhaul connection for the fourth node and the donor-DU of the second node providing backhaul connection for the first node are the same donor-DU, the donor-DU may retransmit the downlink data packet that is not successfully received or transmitted by the third node to the third node directly through the fourth node according to the received information of the reception state of the data packet received by the third node from the first node or the transmission state of the downlink data packet transmitted by the third node, thereby avoiding that the downlink data packet that is not successfully received or transmitted by the third node is retransmitted between the donor-CU and the donor-DU many times in the process of switching the third node.

In order to make the methods provided in the first and second embodiments more clear, a specific example is used to illustrate the handover procedure of the third node. For convenience of description, in the above embodiment, the third node is denoted as node 3, the first node is denoted as S-IAB, the fourth node is denoted as T-IAB, and the host nodes of the first node and the fourth node are the same node and denoted as IAB donor, as shown in fig. 12, the method includes:

1201. node 3 sends a measurement report to the IAB donor. Accordingly, IAB donor receives the measurement report from node 3.

1202. And the IAB donor determines that the node 3 needs to be switched from the S-IAB to the T-IAB according to the measurement report, and sends a context establishment request to the T-IAB.

Among them, IAB donor may send a context setup request to T-IAB through layer F1 AP. The context setup request is for requesting the establishment of a context and bearer for node 3 over the T-IAB.

After step 1202, T-IAB may send a context setup response to IAB donor for feeding back the context of node 3 and the setup condition of the bearer to IAB donor.

1203. The IAB donor sends first indication information to the S-IAB. Accordingly, the S-IAB receives the first indication information from the IAB donor.

The first indication information is used to instruct the S-IAB to stop sending data packets to the node 3. Illustratively, the first indication information may be a context update request.

1204. IAB donor sends a handover command to node 3. Accordingly, node 3 receives a handover command from the IAB donor.

The handover command is for node 3 to switch from S-IAB to T-IAB. The handover command may be an RRC message (e.g., an RRC reconfiguration message).

The IAB donor may specifically send a handover command to node 3 via the S-IAB.

1205. The S-IAB sends a first status report (recorded as a mode 1) to the IAB donor according to the first indication information or the switching command; alternatively, the node 3 sends the third status report to the IAB donor according to the handover command (denoted as mode 2).

The description of the first status report and the third status report can be referred to above, and are not repeated herein.

1206. And the S-IAB sends the cached data packet sent by the node 3 to the IAB donor.

1207. And after the S-IAB finishes sending the last data packet sent by the node 3 cached by the S-IAB, sending third indication information to the IAB donor. Accordingly, the IAB donor receives the third indication information from the S-IAB.

The third indication information is used to indicate that the S-IAB has sent all the uplink data packets sent by the buffered node 3.

1208. And the IAB donor sends the route updating configuration information to an IAB node (marked as I-IAB) between the IAB donor and the T-IAB.

The route update configuration information is used to indicate route information updated to the node 3 or the T-IAB.

Optionally, the IAB donor may send the route update configuration information to the I-IAB through a F1AP message or an RRC message. The route update configuration information may include a QoS mapping rule of a backhaul link related to the I-IAB, so that after the node 3 is switched to the T-IAB, the I-IAB may perform forwarding of a data packet according to a service requirement of the node 3.

1209. And the node 3 initiates random access in the T-IAB and accesses a cell served by the T-IAB.

1210. The node 3 sends a handover complete message to the T-IAB node.

The handover complete message is used to indicate that the node 3 is completed in handover. The handover complete message may be an RRC message (e.g., an RRC reconfiguration complete message).

1211. The T-IAB sends a control plane message containing the handover complete message of node 3 to the IAB donor.

The control plane message is used to notify the IAB donor that the node 3 is completed.

1212. IAB donor instructs S-IAB to release all contexts of node 3.

Wherein, when the node 3 is a wireless backhaul node, the IAB donor may further instruct the S-IAB to release the contexts of all terminals served by the node 3.

1213. And the S-IAB sends a context release completion message of the node 3 to the IAB donor.

The context release complete message is used to inform the completion of context release of node 3 on the IAB donor, S-IAB.

Steps 1212 and 1213 may be performed after step 1207.

EXAMPLE III

For some services with higher reliability requirements, when multiple paths are available between two nodes and only two nodes are shared by the nodes in the multiple paths, the nodes in which packets are split from the two nodes may perform replication of the packets and transmit the packets through the multiple paths, respectively, and the node in which the packets are aggregated (hereinafter, the first node) in the two nodes performs duplicate detection (duplicate detection) of the packets, so as to improve the reliability of transmission. For example, referring to fig. 1, if two paths are available between IAB node 4 and IAB node 1, when a packet is sent from IAB node 4 to IAB node 1, IAB node 4 may duplicate the packet by two, and the two packets are sent through the two paths, respectively, and IAB node 1 performs duplicate detection on the received packet.

When the Adapt layer is between the MAC layer and the RLC layer, if an end-to-end ARQ mode or an end-to-end reassembly mode is used between the terminal and the host node, and IAB nodes on different paths between the terminal and the host node are different, these IAB nodes may segment the RLC SDU of the terminal, and the segmentation modes are independent from each other. In order to reduce the overhead of transmission resources between two nodes having only one path, an embodiment of the present application provides a method for sending a data packet, as shown in fig. 13, including:

1301. the first node receives a plurality of data packets with the same RLC SN through a plurality of paths.

The first node is a node in wireless relay communication. The first node in this embodiment has no direct relationship to the first node above. The plurality of data packets may include RLC SDU segments and/or RLC SDUs.

1302. If the data packet received from the first path in the multiple paths is RLC SDU, the first node sends the RLC SDU to the next hop node of the first node; or, if all the RLC SDU segments received from the multiple paths are RLC SDU segments and there is an RLC SDU segment capable of recovering the RLC SDU in the RLC SDU segments received from the multiple paths, the first node transmits the RLC SDU segment capable of recovering the RLC SDU to a next hop node of the first node, or the first node reassembles the RLC SDU segments received from the multiple paths and transmits the reassembled RLC SDU to the next hop node of the first node; or, if all the RLC SDU segments received from the multiple paths are RLC SDU segments and the RLC SDU segments received from the multiple paths cannot be recovered, the first node transmits the RLC SDU segment received on one of the multiple paths to the next hop node of the first node.

The first path may be any one of a plurality of paths.

In the method provided in this embodiment, when the Adapt layer is located between the MAC layer and the RLC layer and the end-to-end ARQ mode is used between the terminal and the host node, the data packet may be repeatedly detected by the actual aggregation node of the data packet, so that the repeated data packet is prevented from being transmitted between two nodes having only one path, and unnecessary transmission resource overhead is avoided.

Optionally, the method further includes: the first node deletes a data packet other than the data packet transmitted to the next hop node of the first node and having the same SN as the data packet transmitted to the next hop node of the first node. The optional method can delete useless data packets, thereby releasing the storage space of the first node.

Optionally, the end-to-end reassembly refers to reassembling the data packet by two end nodes, and not reassembling the data packet by the other nodes. Illustratively, when a sending node sends a data packet to a receiving node via an intermediate node, the sending node may perform segmentation processing on RLC SDUs in an RLC layer, the intermediate node may also perform segmentation processing on complete RLC SDUs or perform segmentation (segmentation) processing on RLC SDU segments, but the intermediate node does not reassemble the received RLC SDU segments until the RLC SDU segments are transmitted to the receiving node, and the receiving node reassembles the received RLC segments to recover the complete RLC SDUs.

It is understood that when the reassembly mode is an end-to-end reassembly mode, an end-to-end ARQ mode is employed in the IAB network.

The above-mentioned scheme of the embodiment of the present application is introduced mainly from the perspective of interaction between network elements. It will be appreciated that each network element, for example the first node, the second node or the third node, comprises corresponding hardware structures and/or software modules for performing each function in order to implement the above functions. Those of skill in the art would readily appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is performed as hardware or computer software drives hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the embodiment of the present application, the first node, the second node, or the third node may be divided according to the above method examples, for example, each functional unit may be divided corresponding to each function, or two or more functions may be integrated into one processing unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit. It should be noted that the division of the unit in the embodiment of the present application is schematic, and is only a logic function division, and there may be another division manner in actual implementation.

In case of integrated units, fig. 14 shows a schematic diagram of a possible structure of the network node according to the above embodiments, which comprises a processing unit 1401 and a communication unit 1402, and may further comprise a storage unit 1403. The structure diagram shown in fig. 14 may be used to illustrate the structure of the first node, the second node, or the third node in the above embodiments.

When the structure diagram shown in fig. 14 is used to illustrate the structure of the first node in the above embodiment, the processing unit 1401 is configured to control and manage the action of the first node, for example, the processing unit 1401 is configured to support the first node to execute the processes 801 and 802 in fig. 8, the processes 1201, 1203 and 1207, 1212 and 1213 in fig. 12, the steps in fig. 13, and/or the actions executed by the first node in other processes described in this embodiment. The communication unit 1402 is used to support communication between the first node and other network entities, e.g. the second node shown in fig. 8. The storage unit 1403 is used to store program codes and data of the first node.

When the structure diagram shown in fig. 14 is used to illustrate the structure of the second node in the above embodiment, the processing unit 1401 is configured to control and manage the action of the second node, for example, the processing unit 1401 is configured to support the second node to execute the processes 801 and 802 in fig. 8, 1101 and 1102 in fig. 11, 1201 and 1211 and 1213 in fig. 12, and/or the actions executed by the second node in other processes described in this embodiment. The communication unit 1402 is used to support communication between the second node and other network entities, e.g. the first node shown in fig. 8. The storage unit 1403 is used to store program codes and data of the second node.

When the schematic structure diagram shown in fig. 14 is used to illustrate the structure of the third node in the foregoing embodiment, the processing unit 1401 is configured to control and manage the action of the third node, for example, the processing unit 1401 is configured to support the third node to execute the process 1101 and 1102 in fig. 11, the processes 1201, 1204, 1205 (manner two), 1209 and 1210 in fig. 12, and/or the actions executed by the third node in other processes described in this embodiment. The communication unit 1402 is used to support communication between the third node and other network entities, e.g. the second node shown in fig. 11. The storage unit 1403 is used to store program codes and data of the third node.

The processing unit 1401 may be a processor or a controller, and the communication unit 1402 may be a communication interface, a transceiver circuit, etc., wherein the communication interface is generally referred to and may include one or more interfaces. The storage unit 1403 may be a memory.

When the processing unit 1401 is a processor, the communication unit 1402 is a communication interface, and the storage unit 1403 is a memory, the network node according to the embodiment of the present application may be the network node shown in fig. 2.

When the structure diagram shown in fig. 2 is used to illustrate the structure of the first node in the above embodiment, the processor 201 is configured to control and manage the actions of the first node, for example, the processor 201 is configured to support the first node to execute the processes 801 and 802 in fig. 8, the processes 1201, 1203 and 1207, 1212 and 1213 in fig. 12, the steps in fig. 13, and/or the actions executed by the first node in other processes described in this embodiment. The communication interface 204 is used to support communication between the first node and other network entities, for example, the second node shown in fig. 8. The memory 203 is used to store program codes and data of the first node.

When the structure diagram shown in fig. 2 is used to illustrate the structure of the second node in the above embodiment, the processor 201 is configured to control and manage the actions of the second node, for example, the processor 201 is configured to support the second node to execute the processes 801 and 802 in fig. 8, 1101 and 1102 in fig. 11, 1201 and 1211 and 1213 in fig. 12, and/or the actions executed by the second node in other processes described in this embodiment. The communication interface 204 is used to support communication between the second node and other network entities, for example, the first node shown in fig. 8. The memory 203 is used for storing program codes and data of the second node.

When the structure diagram shown in fig. 2 is used to illustrate the structure of the third node in the above embodiment, the processor 201 is configured to control and manage the action of the third node, for example, the processor 201 is configured to support the third node to execute the process 1101 and 1102 in fig. 11, the processes 1201, 1204, 1205 (manner two), 1209 and 1210 in fig. 12, and/or the actions executed by the third node in other processes described in this embodiment. The communication interface 204 is used to support communication between the third node and other network entities, e.g. the second node shown in fig. 11. The memory 203 is used for storing program codes and data of the third node.

Embodiments of the present application also provide a computer-readable storage medium, which includes instructions that, when executed on a computer, cause the computer to perform any of the above methods.

Embodiments of the present application also provide a computer program product containing instructions which, when run on a computer, cause the computer to perform any of the methods described above.

The embodiment of the present application further provides an apparatus, which exists in the form of a chip product, and the apparatus includes a processor, a memory, and a transceiver module, where the transceiver module includes an input/output circuit, the memory is used to store computer execution instructions, and the processor implements any of the above methods by executing the computer execution instructions stored in the memory. In this case, an execution subject for executing the method provided by the embodiment of the present application may be a chip.

The network node in the embodiment of the present application may also be referred to as a network device, for example, the first node may be referred to as a first device, the second node may be referred to as a second device, and the wireless backhaul node may be referred to as a wireless backhaul device.

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

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

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

Claims

1. A method of communication, comprising:

a first node receives first indication information and/or a switching command from a second node, wherein the first indication information is used for indicating the first node to stop sending data packets to a third node, and the switching command is used for switching the third node from the first node to a fourth node;

the first node sends a first status report to the second node, wherein the first status report comprises information used for indicating the sending status of a data packet sent by the first node to the third node;

the second node is a host node of the first node, the third node is a terminal or a wireless backhaul node, the first node is a node providing wireless access service for the third node before the third node is switched, the first node and/or the fourth node are wireless backhaul nodes, and the wireless backhaul nodes are used for providing wireless backhaul service for nodes wirelessly accessing the wireless backhaul nodes; the first node to the fourth node are all nodes in wireless relay communication.

2. The method of claim 1, wherein before the first node sends the first status report to the second node, the method further comprises:

the first node sending a first message to the third node, the first message including information for instructing the third node to report a reception status of a data packet received from the first node;

the first node receiving a second status report from the third node, the second status report including information indicating a reception status of a data packet received by the third node from the first node;

the first node generates the first status report according to the second status report.

3. The method of claim 2, wherein the first node sends a first status report to the second node, comprising:

and the first node sends the first status report to the second node through a node between the first node and the second node, and the node between the first node and the second node is used for converting the information in the status report received from the previous hop node into information which can be identified by the next hop node, placing the information in the status report and sending the information to the next hop node.

4. The method according to claim 3, wherein the status report between any two adjacent nodes in the path between the first node and the previous hop node of the second node includes second indication information, and the second indication information included in one status report is used to indicate the node receiving the status report to convert the information in the status report into information recognizable by the next hop node of the node receiving the status report, and send the information to the next hop node.

5. The method of claim 2, wherein the first node generates the first status report from the second status report, comprising:

the first node generates the first status report according to the corresponding relation of the radio link control sequence number (RLC SN) between the first link and the first path and the RLC SN contained in the second status report; the first link is a link between the first node and the third node, the first path is a path between the first node and the second node, and the RLC SN is a sequence number SN of a radio link control service data unit RLC SDU.

6. The method according to any one of claims 1-5, further comprising:

and the first node sends the cached uplink data packet sent by the third node to the second node, and sends third indication information to the second node, wherein the third indication information is used for indicating that the first node has sent all the cached uplink data packets sent by the third node.

7. The method according to any of claims 1-5, wherein the first status report includes an identifier of the first node, and the identifier of the first node is used to indicate that the information about the transmission status of the data packet included in the first status report is the information about the transmission status of the data packet transmitted by the first node.

8. The method according to any of claims 1-5, wherein the first status report further comprises an identifier of the third node, and the identifier of the third node is used to indicate that the information about the transmission status of the data packet included in the first status report is the information about the transmission status of the data packet transmitted to the third node; or, the first status report further includes an identifier of the third node and an identifier of at least one radio bearer of the third node, where the identifier of the third node and the identifier of the at least one radio bearer of the third node are used to indicate that the information of the transmission status of the data packet included in the first status report is information of the transmission status of the data packet transmitted to the third node through the at least one radio bearer.

9. A method of communication, comprising:

a third node receives a handover command, wherein the handover command is used for the third node to handover from a first node to a fourth node;

the third node sends a third status report to the second node; in a case where the third node is a terminal, the third status report includes information indicating a reception status of a packet received by the third node from the first node; or, in case the third node is a wireless backhaul node, the third status report includes: information for indicating a reception state of a packet received by the third node from the first node, or information for indicating a transmission state of a downlink packet transmitted by the third node;

the first node is a node which provides wireless access service for the third node before the third node is switched, the second node is a host node of the first node, the first node and/or the fourth node is a wireless backhaul node, and the wireless backhaul node is used for providing wireless backhaul service for a node which wirelessly accesses the wireless backhaul node; the first node to the fourth node are all nodes in wireless relay communication.

10. The method of claim 9, wherein the third node sends a third status report to the second node, comprising:

and the third node sends the third status report to the second node through the node between the third node and the second node, and the node between the third node and the second node is used for converting the information in the status report received from the previous hop node into the information which can be identified by the next hop node, and is arranged in the status report to be sent to the next hop node.

11. The method according to claim 10, wherein a status report between any two adjacent nodes in the path between the third node and the previous hop node of the second node includes fourth indication information, and the fourth indication information included in one status report is used to instruct the node receiving the status report to convert the information in the status report into information recognizable by the next hop node of the node receiving the status report, and send the information to the next hop node.

12. The method according to any of claims 9-11, wherein the third node is a wireless backhaul node, the method further comprising:

the third node sending a second message to a terminal served by the third node, the second message including information for instructing the terminal served by the third node to report a reception status of a data packet received from the third node;

the third node receiving status reports of terminals served by the third node, the status report of a terminal including information indicating a reception status of a packet received by the terminal from the third node;

the third node sends a fourth status report to the second node according to the status report of the terminal served by the third node, wherein the fourth status report comprises information for indicating the receiving status of the data packet received by the terminal served by the third node from the third node.

13. The method of claim 12, wherein the fourth status report comprises an identifier of the terminal served by the third node, and the identifier of the terminal served by the third node is used to indicate that the information about the reception status of the data packet included in the fourth status report is the information about the reception status of the data packet received by the terminal served by the third node; or, the fourth status report includes an identifier of the terminal served by the third node and an identifier of at least one radio bearer of the terminal served by the third node, where the identifier of the terminal served by the third node and the identifier of the at least one radio bearer of the terminal served by the third node are used to indicate that the information of the reception state of the data packet included in the fourth status report is the information of the reception state of the data packet received by the terminal served by the third node through the at least one radio bearer.

14. The method according to any of claims 9-11, 13, wherein the third status report comprises an identity of the third node; when the third node is a terminal, the identifier of the third node is used to indicate that the information of the reception status of the data packet included in the third status report is the information of the reception status of the data packet received by the third node; or, in a case that the third node is a wireless backhaul node and the third status report includes information indicating a reception status of a data packet received by the third node from the first node, the information indicating the reception status of the data packet included in the third status report is information indicating a reception status of the data packet received by the third node; or, when the third node is a wireless backhaul node and the third status report includes information indicating a transmission status of a downlink data packet sent by the third node, the identifier of the third node is used to indicate that the information indicating the transmission status of the downlink data packet included in the third status report is the information indicating the transmission status of the downlink data packet sent by the third node.

15. A communications apparatus, comprising: a processing unit and a communication unit;

the processing unit is used for receiving first indication information and/or a switching command from a second node by using the communication unit, wherein the first indication information is used for indicating the communication device to stop sending data packets to a third node, and the switching command is used for switching the third node from the communication device to a fourth node;

the processing unit is further configured to send a first status report to the second node by using the communication unit, where the first status report includes information indicating a sending status of a packet sent by the communication device to the third node;

the second node is a host node of the communication device, the third node is a terminal or a wireless backhaul node, the communication device is a node that provides a wireless access service for the third node before the third node is switched, the communication device and/or the fourth node is a wireless backhaul node, and the wireless backhaul node is configured to provide a wireless backhaul service for a node that wirelessly accesses the wireless backhaul node; the communication device to the fourth node are all nodes in wireless relay communication.

16. The communication device of claim 15,

the processing unit is further configured to send a first message to the third node by using the communication unit, where the first message includes information indicating that the third node reports a reception status of a data packet received from the communication device;

the processing unit is further configured to receive, by the communication unit, a second status report from the third node, where the second status report includes information indicating a reception status of a packet received by the third node from the communication device;

the processing unit is further configured to generate the first status report according to the second status report.

17. The communication device of claim 16,

the processing unit is specifically configured to send the first status report to the second node through a node between the communication device and the second node by using the communication unit, where the node between the communication device and the second node is configured to convert information in the status report received from the previous-hop node into information that can be recognized by the next-hop node, and place the information in the status report and send the information to the next-hop node.

18. The communication apparatus according to claim 17, wherein the status report between any two adjacent nodes in the path between the communication apparatus and the node of the previous hop of the second node includes second indication information, and the second indication information included in one status report is used to instruct the node receiving the status report to convert the information in the status report into information recognizable by the node of the next hop receiving the status report, and send the information to the node of the next hop.

19. The communications device according to claim 16, wherein the processing unit is specifically configured to:

generating the first status report according to the corresponding relation of the radio link control sequence number (RLC SN) between the first link and the first path and the RLC SN contained in the second status report; the first link is a link between the communication device and the third node, the first path is a path between the communication device and the second node, and the RLC SN is a sequence number SN of a radio link control service data unit, RLC SDU.

20. The communication device according to any one of claims 15 to 19,

the processing unit is further configured to send, by using the communication unit, the cached uplink data packet sent by the third node to the second node, and send third indication information to the second node, where the third indication information is used to indicate that the communication device has sent all the uplink data packets sent by the cached third node.

21. The communication apparatus according to any one of claims 15 to 19, wherein the first status report includes an identifier of the communication apparatus, and the information indicating the transmission status of the data packet included in the first status report is information indicating the transmission status of the data packet transmitted by the communication apparatus.

22. The communications apparatus according to any one of claims 15 to 19, wherein the first status report further includes an identifier of the third node, and the identifier of the third node is used to indicate that the information on the transmission status of the data packet included in the first status report is information on the transmission status of the data packet transmitted to the third node; or, the first status report further includes an identifier of the third node and an identifier of at least one radio bearer of the third node, where the identifier of the third node and the identifier of the at least one radio bearer of the third node are used to indicate that the information of the transmission status of the data packet included in the first status report is information of the transmission status of the data packet transmitted to the third node through the at least one radio bearer.

23. A communications apparatus, comprising: a processing unit and a communication unit;

the processing unit is used for receiving a switching command by the communication unit, wherein the switching command is used for switching the communication device from the first node to the fourth node;

the processing unit is further configured to send a third status report to the second node using the communication unit; in a case where the communication apparatus is a terminal, the third status report includes information indicating a reception status of a packet received by the communication apparatus from the first node; alternatively, in case the communication device is a wireless backhaul node, the third status report comprises: information indicating a reception status of a packet received by the communication apparatus from the first node, or information indicating a transmission status of a downlink packet transmitted by the communication apparatus;

wherein the first node is a node providing wireless access service for the communication device before the communication device is switched, the second node is a host node of the first node, and the first node and/or the fourth node are wireless backhaul nodes for providing wireless backhaul service for nodes wirelessly accessing the wireless backhaul nodes; the first node to the fourth node are all nodes in wireless relay communication.

24. The communication device of claim 23,

the processing unit is specifically configured to send the third status report to the second node through a node between the communication device and the second node by using the communication unit, where the node between the communication device and the second node is configured to convert information in the status report received from the previous-hop node into information that can be recognized by the next-hop node, and place the information in the status report and send the information to the next-hop node.

25. The communications apparatus according to claim 24, wherein a fourth indication information is included in the status report between any two adjacent nodes in the path between the communications apparatus and the node of the previous hop of the second node, and the fourth indication information included in one status report is used to instruct the node receiving the status report to convert the information in the status report into information recognizable by the node of the next hop of the node receiving the status report, and send the information to the next hop node.

26. The communication device according to any of claims 23-25, wherein said communication device is a wireless backhaul node,

the processing unit is further configured to send a second message to the terminal served by the communication device by using the communication unit, where the second message includes information indicating that the terminal served by the communication device reports a reception status of the data packet received from the communication device;

the processing unit is further used for receiving the status report of the terminal served by the communication device by using the communication unit, and the status report of one terminal comprises information used for indicating the receiving status of the data packet received by the terminal from the communication device;

the processing unit is further configured to send, to the second node, a fourth status report including information indicating a reception status of a packet received by the terminal served by the communication device from the communication device, according to the status report of the terminal served by the communication device, and by using the communication unit.

27. The communications device of claim 26, wherein the fourth status report includes an identifier of a terminal served by the communications device, and the identifier of the terminal served by the communications device is used to indicate that the information about the reception status of the data packet included in the fourth status report is information about the reception status of the data packet received by the terminal served by the communications device; or, the fourth status report includes an identifier of the terminal served by the communication device and an identifier of at least one radio bearer of the terminal served by the communication device, where the identifier of the terminal served by the communication device and the identifier of the at least one radio bearer of the terminal served by the communication device are used to indicate that the information of the reception status of the data packet included in the fourth status report is information of the reception status of the data packet received by the terminal served by the communication device through the at least one radio bearer.

28. A communications device according to any of claims 23-25, 27, wherein an identity of the communications device is included in the third status report; when the communication device is a terminal, the identifier of the communication device is used for indicating that the information of the receiving state of the data packet contained in the third status report is the information of the receiving state of the data packet received by the communication device; or, in a case where the communication apparatus is a wireless backhaul node and the third status report includes information indicating a reception status of a data packet received by the communication apparatus from the first node, the information indicating the reception status of the data packet included in the third status report is information indicating a reception status of a data packet received by the communication apparatus; or, when the communication device is a wireless backhaul node and the third status report includes information indicating a transmission status of a downlink packet transmitted by the communication device, the information indicating the transmission status of the downlink packet included in the third status report is information indicating a transmission status of a downlink packet transmitted by the communication device.

29. A communications apparatus, comprising: a memory and a processor;

the memory is to store computer-executable instructions that the processor executes to cause the communication device to implement the method of any one of claims 1-8.

30. A communications apparatus, comprising: a memory and a processor;

the memory is to store computer-executable instructions that the processor executes to cause the communication device to implement the method of any one of claims 9-14.