Data retransmission method and apparatus, device, chip, and storage medium

Abstract

The present application provides a data retransmission method and apparatus, a device, a chip, and a storage medium. The method comprises: a receiving end performs data retransmission with a sending end by means of a first protocol layer, the first protocol layer having a data retransmission mechanism.

Description

Data retransmission method, device, equipment, chip and storage medium TECHNICAL FIELD

[0001] The present application relates to the technical field of communication, in particular to a data retransmission method, device, equipment, chip and storage medium. BACKGROUND

[0002] In the related art, a Layer 2 (L2) of a new radio (NR) user plane protocol stack can be divided into a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer and other layers, wherein the PDCP layer and the RLC layer both have a data retransmission mechanism. However, how to simplify the protocol stack so that the data retransmission mechanisms of the PDCP layer and the RLC layer can be combined is a problem to be solved.

[0003] SUMMARY

[0004] The present application provides a data retransmission method, device, equipment, chip and storage medium.

[0005] In a first aspect, the present application provides a data retransmission method, comprising:

[0006] The receiving end performs data retransmission between the receiving end and the sending end through a first protocol layer, and the first protocol layer has a data retransmission mechanism.

[0007] In a second aspect, the present application provides a data retransmission method, comprising:

[0008] The sending end performs data retransmission between the sending end and the receiving end through a first protocol layer, and the first protocol layer has a data retransmission mechanism.

[0009] In a third aspect, the present application provides a data retransmission device, comprising:

[0010] The first communication unit is configured to perform data retransmission between the receiving end and the sending end through a first protocol layer, and the first protocol layer has a data retransmission mechanism.

[0011] In a fourth aspect, the present application provides a data retransmission device, comprising:

[0012] The second communication unit is configured to perform data retransmission between the sending end and the receiving end through a first protocol layer, and the first protocol layer has a data retransmission mechanism.

[0013] In a fifth aspect, the communication device provided in the present application comprises a memory, a processor and a transceiver. The memory is configured to store a computer program; the processor is connected to the memory and is configured to call and run the computer program from the memory, so as to implement the method of the first aspect or the second aspect; and the transceiver is configured to receive and send information in the process of transmitting information with other external devices.

[0014] In a sixth aspect, the chip provided in the present application comprises a memory, a processor and a transceiver. The memory is configured to store a computer program; the processor is connected to the memory and is configured to call and run the computer program from the memory, so as to enable the device installed with the chip to implement the method of the first aspect or the second aspect; and the transceiver is configured to receive and send information in the process of transmitting information with the device or the chip.

[0015] In a seventh aspect, the computer readable storage medium provided in the present application stores a computer program, and the computer program is executed by at least one processor to implement the method of the first aspect or the second aspect.

[0016] In an eighth aspect, the computer program product provided in the present application comprises a computer program or instructions, and the computer program or instructions are executed by a processor to implement the method of the first aspect or the second aspect.

[0017] In a ninth aspect, the computer program provided in the present application enables a computer to implement the method of the first aspect or the second aspect.

[0018] The embodiments of the present application provide a data retransmission method, and the receiving end performs data retransmission with the sending end through a first protocol layer, and the first protocol layer has a data retransmission mechanism. In this way, the data retransmission between the receiving end and the sending end can be implemented in one protocol layer, thereby simplifying the protocol stack and enabling the data retransmission mechanisms of the PDCP layer and the RLC layer to be combined. BRIEF DESCRIPTION OF DRAWINGS

[0019] The accompanying drawings, which are included to provide a further understanding of the present application, constitute a part of the present application, and the illustrative embodiments of the present application and their description serve to explain the present application, and do not constitute improper limitations on the present application. In the drawings:

[0020] FIG. 1 is a schematic diagram of a communication architecture;

[0021] FIG. 2 is a schematic diagram of a data retransmission method according to an embodiment of the present application;

[0022] FIG. 3 is a schematic diagram of a data retransmission method according to an embodiment of the present application;

[0023] FIG. 4 is a flow diagram of a data retransmission method according to an embodiment of the present application;

[0024] FIG. 5 is a structural diagram of a data retransmission apparatus 500 according to an embodiment of the present application;

[0025] FIG. 6 is a structural diagram of a data retransmission apparatus 600 according to an embodiment of the present application;

[0026] FIG. 7 is a structural diagram of a communication device according to an embodiment of the present application;

[0027] FIG. 8 is a schematic structural diagram of a chip according to an embodiment of the present application;

[0028] FIG. 9 is a schematic block diagram of a communication system according to an embodiment of the present application. DETAILED DESCRIPTION

[0029] 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. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0030] FIG. 1 is a schematic diagram of an application scenario according to an embodiment of the present application.

[0031] As shown in FIG. 1, a communication system 100 can include a terminal device 110 and a network device 120. The network device 120 can communicate with the terminal device 110 over an air interface. The terminal device 110 and the network device 120 support multi-service transmission.

[0032] It should be understood that the embodiments of the present application are exemplarily described by taking the communication system 100 as an example, but the embodiments of the present application are not limited thereto. That is, the technical solutions of the embodiments of the present application can be applied to various communication systems, such as a Long Term Evolution (LTE) system, an LTE Time Division Duplex (TDD), a Universal Mobile Telecommunication System (UMTS), an Internet of Things (IoT) system, a Narrow Band Internet of Things (NB-IoT) system, an enhanced Machine-Type Communications (eMTC) system, a 5G communication system (also referred to as an NR communication system), or a future communication system, etc.

[0033] In the communication system 100 shown in FIG. 1, the network device 120 can be an access network device which communicates with the terminal device 110. The access network device can provide communication coverage for a specific geographic area and can communicate with the terminal device 110 located within the coverage area.

[0034] The network device 120 can be an Evolutional Node B (eNB or eNodeB) in an LTE system, or a Next Generation Radio Access Network (NG RAN) device, or a base station (gNB) in an NR system, or a radio controller in a Cloud Radio Access Network (CRAN), or a relay station, an access point, a vehicle-mounted device, a wearable device, a hub, a switch, a bridge, a router, or a network device in a future evolved Public Land Mobile Network (PLMN) and the like.

[0035] The terminal device 110 can be any terminal device, including but not limited to a terminal device connected to the network device 120 or other terminal devices by wire or wireless connection.

[0036] For example, the terminal device 110 can refer to an access terminal, a User Equipment (UE), a subscriber unit, a subscriber station, a mobile station, a mobile, a remote station, a remote terminal, a mobile device, a user terminal, a terminal, a wireless communication device, a user agent or a user equipment. The access terminal can be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, an IoT device, a satellite handset, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a wearable device, a terminal device in a 5G network or a terminal device in a future evolved network, and the like.

[0037] The terminal device 110 can be used for Device to Device (D2D) communication.

[0038] Fig. 1 exemplarily shows one network device and two terminal devices. Optionally, the communication system 100 can include multiple network devices and each network device can include other number of terminal devices within its coverage range, which is not limited in the embodiments of the present application.

[0039] It should be noted that Fig. 1 only schematically shows the system to which the embodiments of the present application are applicable, and of course, the method shown in the embodiments of the present application can also be applicable to other systems. In addition, the terms "system" and "network" are often used interchangeably in the present application.

[0040] In the following description, "some embodiments" are related to a subset of all possible embodiments, but it can be understood that "some embodiments" can be the same subset or different subsets of all possible embodiments, and can be combined with each other without conflict.

[0041] It should be understood that the terms "first\second\third" related in the embodiments of the present application are only used to distinguish similar objects, and do not represent a specific order of the objects. It can be understood that "first\second\third" can be interchanged with a specific order or sequence as allowed, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0042] It should also be understood that the term "and / or" in the present application only describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can represent three cases of A alone, A and B together, and B alone. In addition, the character " / " in the present application generally represents an "or" relationship between the associated objects.

[0043] It should also be understood that "indication" mentioned in the embodiments of the present application can be direct indication or indirect indication, and can also represent an associated relationship. For example, A indicates B, which can mean that B can be obtained by A directly; or A indirectly indicates B, for example, A indicates C, and B can be obtained by C; or A and B have an associated relationship.

[0044] It should also be understood that "corresponding" mentioned in the embodiments of the present application can represent a direct or indirect corresponding relationship between the two, or can represent an associated relationship between the two, or can represent an indication and being indicated, configuration and being configured, etc.

[0045] It should also be understood that the "predefined" or "predefined rule" mentioned in the embodiments of the present application can be implemented by pre-storing corresponding codes, tables or other means for indicating relevant information in the device (for example, including the sending end and the receiving end), and the specific implementation manner is not limited in the present application. For example, the predefined can refer to the definition in the protocol. It should also be understood that the "protocol" in the embodiments of the present application can refer to the standard protocol in the communication field, for example, can include the LTE protocol, the NR protocol and the related protocol applied to the future communication system, and the present application is not limited to this.

[0046] In order to facilitate the understanding of the technical solutions of the embodiments of the present application, the related technologies of the embodiments of the present application are described below, and the following related technologies can be combined with the technical solutions of the embodiments of the present application in any way, which all belong to the protection scope of the embodiments of the present application.

[0047] With the pursuit of rate, delay, high-speed mobility, energy efficiency, and the diversity and complexity of services in future life, the 3rd Generation Partnership Project (3GPP) international standard organization began to develop 5G. The main application scenarios of 5G are: Enhanced Mobile Broadband (eMBB), Ultra Reliable and Low Latency Communications (URLLC), and Massive Machine Type Communication (mMTC). The following will briefly introduce the three application scenarios.

[0048] eMBB aims to provide users with multimedia content, services and data, and its demand is growing rapidly. In addition, since eMBB can be deployed in different scenarios, such as indoor, urban, rural, etc., the differences in its capabilities and requirements are also quite large, so it cannot be generalized and must be analyzed in detail in combination with the specific deployment scenario.

[0049] Typical applications of URLLC can include industrial automation, power automation, remote medical operations (surgery), traffic safety assurance, etc.

[0050] The typical characteristics of mMTC can include high connection density, small data volume, delay-insensitive services, low-cost modules and long service life, etc.

[0051] NR can also be deployed independently, in order to reduce air interface signaling, quickly recover wireless connection, and quickly recover data service in a 5G network environment, a new radio resource control (RRC) state, i.e. RRC inactive (RRC_INACTIVE) state, is defined. This state is different from RRC idle (RRC_IDLE) state and RRC active (RRC_ACTIVE) state. The following briefly describes the three states respectively.

[0052] RRC_INACTIVE state: mobility is based on terminal device cell selection and reselection, there is a connection between core network (CN) and NR, terminal device access stratum (AS) context exists on a certain satellite, paging is triggered by RAN, RAN-based paging area is managed by RAN, and the satellite side knows the location of the terminal device based on the RAN-based paging area level.

[0053] RRC_IDLE state: mobility is based on terminal device cell selection and reselection, paging is initiated by CN, and paging area is configured by CN. There is no terminal device AS context on the network device side. There is no RRC connection.

[0054] RRC_ACTIVE state: there is an RRC connection, and the network device and the terminal device have terminal device AS context. The network device side knows the location of the terminal device at the specific cell level. Mobility is network device side controlled mobility. Unicast data can be transmitted between the terminal device and the network device.

[0055] The L2 of the NR user plane protocol stack can be divided into four sub-layers: media access control (MAC) layer, RLC layer, PDCP layer, and service data adaptation protocol (SDAP) layer.

[0056] For uplink transmission, the PDCP layer is mainly responsible for processing the PDCP service data unit (SDU) received from the SDAP layer, and after generating the PDCP protocol data unit (PDU) through processing, it is delivered to the corresponding RLC layer.

[0057] For downlink transmission, the PDCP layer is mainly responsible for receiving the PDCP PDU delivered from the RLC layer, processing and delivering to the SDAP layer after removing the PDCP header. The PDCP layer and the radio bearer are one-to-one corresponding, that is, each radio bearer (including signaling radio bearer (SRB) and data radio bearer (DRB)) is associated with a PDCP entity. Most of the functions provided by the NR PDCP layer are similar to those of LTE, which can mainly include the following aspects.

[0058] Maintenance of the sending or receiving side sequence number of the PDCP layer;

[0059] Header compression and decompression;

[0060] Encryption and decryption, integrity protection;

[0061] Timer-based PDCP SDU discard;

[0062] Support for routing function for split bearer;

[0063] Copy transmission function;

[0064] Reordering and in-sequence delivery function.

[0065] The PDCP layer is similar to LTE in the data transceiving process. The improvement of the PDCP layer compared with LTE is that the NR PDCP adopts an absolute count value (COUNT) based method in the maintenance of the local variable of the data transceiving process and the conditional comparison, which can improve the readability of the protocol. The COUNT can include a sequence number (SN) and a hyperframe number, and the size is fixed at 32 bits. It should be noted that the header part of the PDCP PDU still contains the SN, not the COUNT value, so it will not increase the air transmission overhead.

[0066] Exemplarily, for uplink transmission, the PDCP transmission side maintains a local COUNT value of TX_NEXT, which is initially set to 0. For each new PDCP PDU generated, the SN in the corresponding header is set to the value corresponding to the TX_NEXT, and the TX_NEXT is increased by 1. The PDCP transmission side performs header compression, integrity protection and encryption operations on the PDCP SDU according to the network configuration. For downlink transmission, the PDCP receiving side maintains a receiving window according to the COUNT value of the local variable, and the receiving window has the following local variables.

[0067] RX_NEXT: the COUNT value corresponding to the next expected received PDCP SDU.

[0068] RX_DELIV: COUNT value corresponding to the next PDCP SDU expected to be delivered to the upper layer. This variable determines the lower boundary of the reception window.

[0069] RX_REORD: COUNT corresponding to the PDCP PDU triggering the reordering timer.

[0070] Based on the PUSH window mechanism, the PDCP receiving side processes the received PDCP PDU.

[0071] The NR PDCP also supports duplicated data transmission, which is to simply copy the PDCP PDU into two identical parts based on the configuration and activation instructions of the network side, and deliver them to different RLC entities.

[0072] In the related art, the PDCP layer and the RLC layer both have data retransmission mechanisms, thereby increasing the complexity of the protocol stack. Therefore, how to simplify the protocol stack so that the data retransmission mechanisms of the PDCP layer and the RLC layer can be combined is a problem to be solved.

[0073] Based on this, the embodiment of the present application provides a data retransmission method, the receiving end performs data retransmission between the sending end through a first protocol layer, and the first protocol layer has a data retransmission mechanism. In this way, the data retransmission between the receiving end and the sending end can be implemented in one protocol layer, thereby simplifying the protocol stack and enabling the data retransmission mechanisms of the PDCP layer and the RLC layer to be combined.

[0074] In order to facilitate understanding of the technical solutions of the embodiments of the present application, the technical solutions of the present application are described in detail below through specific embodiments. The above related technologies can be combined with the technical solutions of the embodiments of the present application as optional solutions, and all belong to the protection scope of the embodiments of the present application. The embodiments of the present application include at least part of the following contents.

[0075] It should be understood that the following embodiments refer to data packets multiple times, which can be understood as that the number of data packets can be one or multiple in general, and the embodiments of the present application do not limit this.

[0076] FIG. 2 is a flowchart of a data retransmission method according to an embodiment of the present application, as shown in FIG. 2, the method can include the following steps.

[0077] S210, the receiving end performs data retransmission between the sending end through a first protocol layer, and the first protocol layer has a data retransmission mechanism.

[0078] Correspondingly, the sending end can perform data retransmission between the receiving end through a first protocol layer, and the first protocol layer has a data retransmission mechanism.

[0079] It should be noted that the receiving end can include a receiving entity, and the sending end can include a sending entity. The sending end can be located at the terminal device side, and the receiving end can be located at the network device side. Alternatively, the sending end can be located at the network device side, and the receiving end can be located at the terminal device side.

[0080] It should be further noted that, compared with the PDCP layer and the RLC layer both having the data retransmission mechanism in the related art, the data retransmission mechanism of the PDCP layer and the RLC layer can be combined in the embodiments of the present application, so that the data retransmission is implemented through one protocol layer, thereby simplifying the protocol stack.

[0081] In some embodiments, the first protocol layer replaces the PDCP layer and / or the RLC layer; or,

[0082] The first protocol layer is the PDCP layer, and the RLC layer does not exist; or,

[0083] The first protocol layer is the PDCP layer, and the RLC layer does not have the data retransmission mechanism; or,

[0084] The first protocol layer has the data retransmission mechanism of the PDCP layer and the RLC layer, and the RLC layer does not exist; or,

[0085] The first protocol layer has the data retransmission mechanism of the PDCP layer and the RLC layer, and the RLC layer does not have the data retransmission mechanism; or,

[0086] The first protocol layer has the data retransmission mechanism of the PDCP layer and the RLC layer, and the PDCP layer does not exist; or,

[0087] The first protocol layer has the data retransmission mechanism of the PDCP layer and the RLC layer, and the PDCP layer does not have the data retransmission mechanism; or,

[0088] The first protocol layer is the RLC layer, and the PDCP layer does not have the data retransmission mechanism; or,

[0089] The first protocol layer is the RLC layer, and the PDCP layer does not exist.

[0090] It should be noted that the first protocol layer replaces the PDCP layer and the RLC layer, which can be understood as that the first protocol layer is a new protocol layer different from the PDCP layer and the RLC layer, and the new protocol layer has the data retransmission mechanism, and the PDCP layer and the RLC layer can exist, and the PDCP layer and the RLC layer do not have the data retransmission mechanism.

[0091] It should be further noted that the first protocol layer replaces the PDCP layer, which can be understood as that the first protocol layer is a new protocol layer different from the PDCP layer, and the new protocol layer has a data retransmission mechanism. At this time, the PDCP layer can exist, and the PDCP layer does not have a data retransmission mechanism.

[0092] It should be further noted that the first protocol layer replaces the RLC layer, which can be understood as that the first protocol layer is a new protocol layer different from the RLC layer, and the new protocol layer has a data retransmission mechanism. At this time, the RLC layer can exist, and the RLC layer does not have a data retransmission mechanism.

[0093] It should be further noted that the protocol layer (such as the PDCP layer, and the RLC layer) does not exist, which is not equivalent to the protocol layer not having a data retransmission mechanism. That is, in the case that the protocol layer does not have a data retransmission mechanism, the protocol layer can exist.

[0094] It should be further noted that in the case that the first protocol layer has a data retransmission mechanism of the PDCP layer and the RLC layer, the first protocol layer can be the PDCP layer, at this time it can be considered that the data retransmission mechanisms of the PDCP layer and the RLC layer are combined in the PDCP layer; or the first protocol layer can be the RLC layer, at this time it can be considered that the data retransmission mechanisms of the PDCP layer and the RLC layer are combined in the RLC layer; or the first protocol layer can be a combined protocol layer, at this time it can be considered that the data retransmission mechanisms of the PDCP layer and the RLC layer are combined in a protocol layer.

[0095] Exemplarily, in the case that the first protocol layer is the PDCP layer, the sending end can include a sending PDCP entity, and the receiving end can include a receiving PDCP entity.

[0096] Exemplarily, in the case that the first protocol layer is the RLC layer, the sending end can include a sending RLC entity, and the receiving end can include a receiving RLC entity.

[0097] Exemplarily, in the case that the first protocol layer is a new protocol layer, the sending end can include a sending entity, and the receiving end can include a receiving entity.

[0098] In the embodiments of the present application, the data retransmission between the receiving end and the sending end can be triggered by the receiving end or the sending end, and the embodiments of the present application do not limit the same. Based on different trigger objects, the trigger mode of data retransmission can be divided into the following two modes.

[0099] Mode A, the data retransmission between the receiving end and the sending end is triggered by the receiving end based on a first condition.

[0100] Wherein, whether triggered by the receiving end and / or the trigger of the receiving end is configured by the network device, determined by the receiving end, determined according to rules or specified by protocols.

[0101] Wherein, the first condition can be configured by the network device, determined by the receiving end, determined according to rules or specified by protocols.

[0102] It should be noted that whether triggered by the receiving end can be understood as whether the trigger object is the receiving end; the trigger of the receiving end can be understood as, in the case of the trigger object being the receiving end, how the receiving end implements the trigger (such as triggering based on the first condition).

[0103] In some embodiments, the first condition includes one or more of the following:

[0104] The remaining time of the first timer is less than or equal to a first threshold value;

[0105] The second timer is timed out or not running;

[0106] The number of compression or decompression failures is greater than or equal to a second threshold value.

[0107] Exemplarily, the first timer can be a re-ordering timer (Re-Ordering Timer).

[0108] Exemplarily, the second timer can be a reassembly timer (t-Reassembly).

[0109] Exemplarily, the number of robust header compression (RoHC) failures is greater than or equal to a second threshold value.

[0110] It should be noted that the number of compression or decompression failures can be one or more, and the embodiments of the present application do not limit this.

[0111] It should also be noted that the first threshold value can be specified by protocols or determined in other ways, and the embodiments of the present application do not limit this.

[0112] It should also be noted that the second threshold value can be specified by protocols or determined in other ways, and the embodiments of the present application do not limit this.

[0113] Further, the number of compression or decompression failures is configured by the network device; or,

[0114] The number of compression or decompression failures is specified by protocols; or,

[0115] The number of compression or decompression failures is determined by the receiving end; or,

[0116] The number of compression or decompression failures is determined by negotiation between the receiving end and the sending end.

[0117] Through the method, the condition for the receiving end to trigger data retransmission can be determined, so that the receiving end can trigger data retransmission with the sending end based on the first condition.

[0118] In some embodiments, the method can further include that the data retransmission is retransmission of a specific data packet, or retransmission of specific N data packets, or retransmission of data packets corresponding to a logical channel (LCH) or PDCP or RLC or DRB; wherein N is a positive integer.

[0119] In some embodiments, the method can further include that the data retransmission is retransmission of a PDU set, or retransmission of a PDU, or retransmission of an SDU, or retransmission of an SDU segment, or retransmission of a data burst.

[0120] In some embodiments, the method can further include that, in the case where the first timer expires, the receiving end submits data packets to a high layer of the first protocol layer.

[0121] Exemplarily, the high layer of the first protocol layer can be an SDAP layer, or other protocol layers, which are not limited in the embodiments of the present application.

[0122] It should be noted that the number of data packets submitted by the receiving end can be one or multiple, which is not limited in the embodiments of the present application.

[0123] In some embodiments, the method can further include that the receiving end determines that data packets with sequence numbers less than or equal to a third threshold value have been correctly received; wherein the third threshold value is a maximum sequence number in the sequence numbers of the data packets received by the receiving end, or a maximum sequence number in the sequence numbers of the submitted data packets.

[0124] It should be noted that “determines” can be replaced by “considers” equivalently. That is, the receiving end can consider that data packets with sequence numbers less than or equal to the third threshold value have been correctly received.

[0125] Through the method, in the case where the first timer expires, the receiving end can submit data packets to a high layer of the first protocol layer, so as to realize data interaction between different protocol layers.

[0126] It should be understood that the data retransmission between the receiving end and the sending end can be triggered directly by the receiving end based on the first condition, or can be associated with the PDU sent by the sending end, and the data retransmission between the receiving end and the sending end is performed through the PDU sent by the sending end.

[0127] In some embodiments, the method can further comprise: sending, by the sending end, a first PDU to the receiving end; wherein the first PDU comprises an indication field with a first value, and the first PDU is used to instruct the receiving end to trigger data retransmission between the sending end and the receiving end, or is used to trigger data retransmission between the sending end and the receiving end.

[0128] Correspondingly, the receiving end receives the first PDU sent by the sending end.

[0129] Exemplarily, the indication field can be a polling field.

[0130] Exemplarily, the first value can be 1.

[0131] It should be noted that, in the case where the first PDU is used to instruct the receiving end to trigger data retransmission between the sending end and the receiving end, the data retransmission is triggered by the receiving end, for example, the receiving end can trigger data retransmission based on a first condition; in the case where the first PDU is used to trigger data retransmission between the sending end and the receiving end, the receiving end does not need to trigger data retransmission again, and after receiving the first PDU, the receiving end can directly send a status report to the sending end.

[0132] Through the method, the sending end can achieve data retransmission between the receiving end and the sending end through a first protocol layer by sending a first PDU to the receiving end, thereby simplifying the protocol stack and enabling the data retransmission mechanisms of the PDCP layer and the RLC layer to be combined.

[0133] In some embodiments, the sending end sending a first PDU to the receiving end can comprise:

[0134] The sending end sends the first PDU to the receiving end based on one or more of the following:

[0135] The number of data packets without polling or the number of PDUs without carrying polling information is greater than or equal to an eighth threshold value;

[0136] The data volume of data packets without polling or the data volume of PDUs without carrying polling information is greater than or equal to a ninth threshold value;

[0137] There is no PDU in the transmission buffer of the sending end;

[0138] A fourth timer is expired, the fourth timer is started after the sending end sends a second PDU, and the second PDU comprises an indication field with the first value;

[0139] There is a data packet with a delay or a remaining delay less than or equal to a certain threshold value.

[0140] It should be noted that the PDU includes the indication field with the first value, indicating that the PDU is a PDU that has been inquired or carries inquiry information; similarly, the data packet without inquiry or the PDU without carrying inquiry information does not include the indication field with the first value.

[0141] It should be further noted that the fourth timer can be started after the sending end sends the second PDU, or restarted after the sending end sends the second PDU, and the embodiments of the present application do not limit this.

[0142] It should be further noted that the eighth threshold value can be specified by a protocol or determined in other manners, and the embodiments of the present application do not limit this.

[0143] It should be further noted that the ninth threshold value can be specified by a protocol or determined in other manners, and the embodiments of the present application do not limit this.

[0144] Exemplarily, the fourth timer can be a retransmission timer (such as a poll retransmission timer (t-PollRetransmit)).

[0145] Through the method, the sending end can realize data retransmission between the receiving end and the sending end through the first protocol layer by sending the first PDU to the receiving end, thereby simplifying the protocol stack and enabling the data retransmission mechanisms of the PDCP layer and the RLC layer to be combined.

[0146] It should be understood that after the receiving end triggers the data retransmission between the receiving end and the sending end based on the first condition, and / or after the receiving end receives the first PDU sent by the sending end, the receiving end can send retransmission indication information to the sending end to instruct the sending end to send retransmission data to the receiving end.

[0147] In some embodiments, the method can further include that the receiving end sends a status report to the sending end, and the status report is used to indicate one or more of the following:

[0148] The transmission status of the data packet;

[0149] The reception status of the data packet;

[0150] The data packet that needs to be retransmitted.

[0151] Correspondingly, the sending end receives the status report sent by the receiving end.

[0152] It should be noted that the retransmission indication information can include the status report.

[0153] Further, the status report indicates one or more of the following:

[0154] Sequence number and / or count value of the data packet requiring retransmission;

[0155] Sequence number and / or count value of the data packet not requiring retransmission;

[0156] Successful transmission, or erroneous transmission, or non-successful transmission of the data packet;

[0157] Successful reception, or erroneous reception, or non-reception of the data packet;

[0158] Transmission status of the lost data packet;

[0159] Transmission status of the non-received data packet;

[0160] Transmission status or reception status of the received data packet;

[0161] Transmission status or reception status of the data packet starting from the first data packet with a reception status of Negative Acknowledgement (NACK);

[0162] Transmission status or reception status of the data packet starting from the first data packet with a reception status of Acknowledgement (ACK);

[0163] Transmission status or reception status of the data packet starting from the first lost data packet;

[0164] Retransmission granularity;

[0165] Performing PDU retransmission, or the data packet requiring retransmission is a PDU;

[0166] Performing SDU or SDU segment retransmission, or the data packet requiring retransmission is an SDU or an SDU segment.

[0167] It should be noted that the content and / or format of the status report can be similar to the status report in the related art.

[0168] It should also be noted that the retransmission granularity can represent whether the sending end performs PDU retransmission or SDU or SDU segment retransmission.

[0169] Through the method, the sending end can receive the status report sent by the receiving end, so that the sending end can subsequently send retransmission data to the receiving end based on the status report.

[0170] In some embodiments, the method can further include that the sending end retransmits one or more of the following to the receiving end: a PDU set, a Data Burst, a PDU, an SDU, and an SDU segment.

[0171] It should be understood that the sending end can send retransmission data to the receiving end based on the status report, or the sending end can send retransmission data to the receiving end based on the reestablishment scenario. The following describes two possible implementation manners of the sending end sending retransmission data to the receiving end.

[0172] In a possible implementation manner, the sending end retransmits one or more of the PDU set, the Data Burst, the PDU, the SDU, or the SDU segment to the receiving end based on the reestablishment scenario.

[0173] In some embodiments, the sending end retransmits one or more of the PDU set, the Data Burst, the PDU, the SDU, or the SDU segment to the receiving end, which can include that, in the case that the first protocol layer is in the reestablishment state, the sending end retransmits the SDU or the SDU segment to the receiving end, or performs retransmission based on the SDU or the SDU segment; and / or,

[0174] In the case that the high layer of the first protocol layer instructs the first protocol layer to reestablish, the sending end retransmits the SDU or the SDU segment to the receiving end, or performs retransmission based on the SDU or the SDU segment.

[0175] Exemplarily, the high layer of the first protocol layer can be an SDAP layer, or can be another protocol layer, and the embodiments of the present application do not limit this.

[0176] Through the method, the sending end can retransmit the SDU or the SDU segment to the receiving end based on the reestablishment scenario, which realizes data retransmission between the receiving end and the sending end at one protocol layer, thereby simplifying the protocol stack and enabling the data retransmission mechanisms of the PDCP layer and the RLC layer to be combined.

[0177] In another possible implementation manner, the sending end can retransmit one or more of the PDU set, the Data Burst, the PDU, the SDU, or the SDU segment to the receiving end based on the status report.

[0178] In some embodiments, the sending end retransmits one or more of the PDU set, the Data Burst, the PDU, the SDU, or the SDU segment to the receiving end, which can include that, in the case that the status report indicates that the data packet that needs to be retransmitted is a PDU, the sending end retransmits the PDU to the receiving end, or performs retransmission based on the PDU; and / or,

[0179] In the case that the status report indicates that the data packet that needs to be retransmitted is an SDU or an SDU segment, the sending end retransmits the SDU or the SDU segment to the receiving end, or performs retransmission based on the SDU or the SDU segment.

[0180] By the method, the sending end can determine whether to retransmit the PDU or the SDU or the SDU segment to the receiving end based on the indication of the status report, realize the data retransmission between the receiving end and the sending end at one protocol layer, thereby simplifying the protocol stack, and enabling the data retransmission mechanisms of the PDCP layer and the RLC layer to be combined.

[0181] In some embodiments, the method can further include: in the case that the status report indicates the receiving status and / or the transmission status of the data packet, the sending end retransmits one or more of the following data packets to the receiving end:

[0182] the un-received data packet;

[0183] the NACKed data packet;

[0184] the lost data packet;

[0185] the error-transmitted data packet;

[0186] the error-received data packet;

[0187] the unsuccessfully-transmitted data packet.

[0188] It should be noted that in the case that the status report indicates one or more of the successful transmission, the successful reception, and the ACK, the sending end can not retransmit the data packet to the receiving end, and / or the sending end can discard the data packet.

[0189] By the method, the sending end can determine the type of the data packet to be retransmitted to the receiving end based on the indication of the status report, realize the data retransmission between the receiving end and the sending end at one protocol layer, thereby simplifying the protocol stack, and enabling the data retransmission mechanisms of the PDCP layer and the RLC layer to be combined.

[0190] The data retransmission between the sending end and the receiving end can be illustrated by the flowchart shown in FIG. 3. Exemplarily, as shown in FIG. 3, assuming that the receiving end is located at the network device side and the sending end is located at the terminal device side, the method can include the following steps.

[0191] S310, triggering the data retransmission between the receiving end and the sending end.

[0192] It should be noted that the data retransmission can be triggered by the receiving end based on the first condition, triggered by the first PDU sent by the sending end, or triggered by the sending end in the case that the first PDU is sent, and the embodiments of the present application do not limit this.

[0193] It should be noted that, before triggering the data retransmission between the receiving end and the sending end, the network device can configure, the receiving end can determine, the rule can determine, or the protocol can stipulate that the data retransmission between the receiving end and the sending end is implemented through the first protocol layer, and / or whether it is triggered by the receiving end; and / or whether it is triggered by the sending end.

[0194] S320, the receiving end sends a status report to the sending end.

[0195] Correspondingly, the sending end receives the status report sent by the receiving end.

[0196] It should be noted that the receiving end can send a status report to the sending end after triggering the data retransmission based on the first condition; and / or the receiving end can send a status report to the sending end after receiving the first PDU, which is not limited by the embodiments of the application.

[0197] S330, the sending end sends retransmission data to the receiving end.

[0198] Correspondingly, the receiving end receives the retransmission data sent by the sending end.

[0199] It should be noted that the sending end can retransmit data to the receiving end based on the status report; or the sending end can retransmit data to the receiving end based on the reconstruction scenario.

[0200] Through the method A, the receiving end can trigger the data retransmission between the receiving end and the sending end at the first protocol layer based on the first condition, thereby simplifying the protocol stack and enabling the data retransmission mechanisms of the PDCP layer and the RLC layer to be combined.

[0201] Method B, the data retransmission between the receiving end and the sending end is triggered by the sending end based on a second condition.

[0202] Wherein, whether triggered by the sending end and / or the sending end is network device configuration, sending end implementation determination, rule determination, or protocol stipulation.

[0203] Wherein, the second condition can be network device configuration, receiving end implementation determination, rule determination, or protocol stipulation.

[0204] It should be noted that whether triggered by the sending end can be understood as whether the triggering object is the sending end; the sending end trigger can be understood as, in the case that the triggering object is the sending end, how the sending end implements the trigger (such as triggering based on the second condition).

[0205] In some embodiments, the sending end triggers the indication information based on the second condition, and the indication information is used for the receiving end to send a status report, or to trigger the receiving end to perform information interaction related to reselection, or to trigger the receiving end to trigger data retransmission between the receiving end and the sending end.

[0206] In some other embodiments, the sending end performs data retransmission with the receiving end based on the second condition, or performs data packet retransmission when the second condition is met.

[0207] In some embodiments, the second condition comprises one or more of the following:

[0208] a remaining time of the data packet is less than or equal to a fourth threshold value;

[0209] a remaining time of the third timer is less than or equal to a fifth threshold value;

[0210] a remaining time of the data packet is less than or equal to a sixth threshold value, and the data packet is a data packet belonging to a first type;

[0211] a remaining time of the third timer is less than or equal to a seventh threshold value, and the data packet is a data packet belonging to a first type;

[0212] a number of data packets without a probe or a number of PDUs without carrying a probe information is greater than or equal to an eighth threshold value;

[0213] a data amount of data packets without a probe or a data amount of PDUs without carrying a probe information is greater than or equal to a ninth threshold value;

[0214] there is no PDU in a transmission buffer of the sending end;

[0215] a fourth timer expires, the fourth timer being started after the sending end sends a second PDU, the second PDU comprising an indication field with a first value.

[0216] It should be noted that the fourth threshold value, the fifth threshold value, the sixth threshold value, and the seventh threshold value can be defined by a protocol or determined in other manners, and the embodiments of the present application do not limit the same.

[0217] It should also be noted that the PDU comprising the indication field with the first value indicates that the PDU is a PDU with a probe or carrying a probe information; similarly, the data packet without a probe or the PDU without carrying a probe information does not comprise the indication field with the first value.

[0218] It should also be noted that the fourth timer can be started after the sending end sends the second PDU, or restarted after the sending end sends the second PDU, and the embodiments of the present application do not limit the same.

[0219] Exemplarily, the third timer can be a discard timer.

[0220] Exemplarily, the fourth timer can be t-PollRetransmit.

[0221] It should be noted that the remaining time of the data packet can be understood as the time left from the sending of the data packet by the sending end to the retransmission of the data packet.

[0222] It should be further noted that the remaining time of the third timer can be understood as the time left from the sending of the data packet by the sending end to the discarding of the data packet.

[0223] It should be further noted that in the case that the remaining time of the data packet is less than or equal to the sixth threshold value, the transmission time of the data packet can be greater than or equal to a certain threshold value.

[0224] Further, the data packet of the first type includes one or more of the following data packets:

[0225] a data packet belonging to a specific identifier;

[0226] a data packet belonging to a first DRB, and a logical channel priority of the first DRB being greater than or equal to a tenth threshold value;

[0227] a data packet belonging to a second DRB, and a reliability requirement corresponding to the second DRB being greater than or equal to an eleventh threshold value, or a reliability identifier of the second DRB being a specific identifier;

[0228] a data packet belonging to a third DRB, and an importance requirement corresponding to the third DRB being greater than or equal to a twelfth threshold value, or an importance identifier of the third DRB being a specific identifier;

[0229] a data packet belonging to a first PDU set, and a sequence number of the first PDU set being a thirteenth threshold value, or other data packets with the same sequence number as the first PDU set having been transmitted;

[0230] a data packet belonging to a second PDU set, and the data packet of the second PDU set being an independent or independently decoded data packet, or an independent identifier or independently decoded identifier of the data packet of the second PDU set being a specific identifier;

[0231] a data packet belonging to a third PDU set, and an identifier of the third PDU set being greater than or equal to a fourteenth threshold value;

[0232] a data packet with a reliability requirement greater than or equal to the eleventh threshold value or a reliability identifier being a specific identifier;

[0233] a data packet belonging to a first PDU set and having a sequence number greater than or equal to a thirteenth threshold value;

[0234] a data packet belonging to a first PDU set and having a sequence number greater than or equal to a thirteenth threshold value;

[0235] a data packet belonging to a first PDU set and having a sequence number greater than or equal to a thirteenth threshold value.

[0236] It should be noted that the tenth threshold value, the eleventh threshold value, the twelfth threshold value, the thirteenth threshold value, and the fourteenth threshold value can be protocol specified or determined in other manners, and the embodiments of the present application do not limit this.

[0237] It should be further noted that the terminal device can know, based on the high-layer information, which type (such as an I frame or a P frame) of data packet the first PDU set corresponding to the sequence number of the first PDU set is. For example, the terminal device can know that the first PDU set with the thirteenth threshold value of the sequence number is a data packet of an I frame.

[0238] It should be further noted that the independent data packet is a data packet that other data packets need to rely on for decoding.

[0239] It should be further noted that the identification as a specific identification can be understood as that the semantic features of the identification can be known to obtain the meaning of the identification, and then the type of the data packet corresponding to the identification is known. For example, the identification includes the word "important", which indicates that the data packet meets the importance requirement; for another example, the identification includes the word "reliable", which indicates that the data packet meets the reliability requirement; for another example, the identification includes the word "independent", which indicates that the data packet meets the independence requirement.

[0240] Exemplarily, in a case where the data packet belongs to a data packet of the first PDU set and other data packets with the same sequence number of the first PDU set have been transmitted, if the remaining time of the data packet is less than or equal to the sixth threshold value, the sending end can send the receiving end with retransmission data; and / or, if the transmission time of the data packet is greater than or equal to a certain threshold value, the sending end can send the receiving end with retransmission data.

[0241] Exemplarily, in a case where the data packet belongs to a data packet of the specific identification, and / or the remaining time of the data packet is less than or equal to the sixth threshold value, and / or if the transmission time of the data packet is greater than or equal to a certain threshold value, the sending end can send the receiving end with retransmission data.

[0242] Through the method, the condition for the sending end to trigger data retransmission can be determined, so that the sending end can trigger data retransmission with the receiving end based on the second condition.

[0243] The data retransmission between the sending end and the receiving end can be illustrated by the flowchart shown in FIG. 4. For example, as shown in FIG. 4, it is assumed that the receiving end is located at the network device side and the sending end is located at the terminal device side. The method can include the following steps.

[0244] S410, triggering the data retransmission between the receiving end and the sending end.

[0245] It should be noted that the data retransmission can be triggered by the sending end based on the second condition.

[0246] It should be further noted that before triggering the data retransmission between the receiving end and the sending end, the network device can configure, the receiving end can determine, the rule can determine, or the protocol can stipulate that the data retransmission between the receiving end and the sending end is implemented through the first protocol layer, and / or whether it is triggered by the sending end.

[0247] S420, the sending end sends the retransmission data to the receiving end.

[0248] Correspondingly, the receiving end receives the retransmission data sent by the sending end.

[0249] Through the method B, the sending end can trigger the data retransmission between the receiving end and the sending end at the first protocol layer based on the second condition, thereby simplifying the protocol stack and enabling the data retransmission mechanisms of the PDCP layer and the RLC layer to be combined.

[0250] It should be noted that the method A and the method B can be used alone or in combination, and the embodiments of the present application do not limit this. For example, the data retransmission between the receiving end and the sending end can exist both in the triggering of the sending end based on the second condition and in the triggering of the receiving end based on the first condition.

[0251] The embodiments of the present application provide a data retransmission method. The receiving end performs data retransmission through the first protocol layer with the sending end, and the first protocol layer has a data retransmission mechanism. In this way, the data retransmission between the receiving end and the sending end can be implemented at one protocol layer, thereby simplifying the protocol stack and enabling the data retransmission mechanisms of the PDCP layer and the RLC layer to be combined.

[0252] The data retransmission method provided by the embodiments of the present application will be described in detail in combination with specific application scenarios.

[0253] In the embodiments of the present application, data retransmission can be performed at the PDCP layer, data retransmission is not performed at the RLC layer (the RLC layer still exists); or data retransmission can be performed at the PDCP layer, the RLC layer does not exist; or data retransmission can be performed at the RLC layer, data retransmission is not performed at the PDCP layer (the PDCP layer still exists); or data retransmission can be performed at the RLC layer, the PDCP layer does not exist; or the retransmission functions (i.e., retransmission mechanisms) of the RLC and the PDCP can be combined and implemented at the PDCP layer; or the retransmission functions of the RLC and the PDCP can be combined and implemented at the RLC layer; or one protocol layer can be used to replace the PDCP layer and / or the RLC layer, and data retransmission can be performed at the protocol layer, and the embodiments of the present application do not limit this.

[0254] In the following embodiments, data retransmission is taken as an example to be performed at the PDCP layer, and it can be understood that the scheme of performing data retransmission at other protocol layers is similar to the scheme of performing data retransmission at the PDCP layer, and details are not described herein.

[0255] When data retransmission is performed at the PDCP layer, the sending end can include a sending PDCP entity, the receiving end can include a receiving PDCP entity, data retransmission at the PDCP layer can simplify the protocol stack, and combine the data retransmission function, so that data retransmission is implemented at the PDCP layer.

[0256] In the following, embodiments one and two are combined to respectively describe the sending PDCP entity triggering data retransmission and the receiving PDCP entity triggering data retransmission.

[0257] Embodiment one, the receiving PDCP entity triggers data retransmission.

[0258] (1) The manner in which the receiving PDCP entity triggers the sending PDCP entity to perform data retransmission is determined.

[0259] The receiving PDCP entity triggering the sending PDCP entity to perform data retransmission can be configured by a network device, determined by the receiving PDCP entity, determined according to a rule, specified by a protocol, or optional.

[0260] The receiving PDCP entity can trigger the sending PDCP entity to perform data retransmission based on a first condition.

[0261] In some embodiments, the first condition can be configured by a network device, specified by a protocol, determined by the receiving PDCP entity, determined according to a rule, or specified by a protocol.

[0262] In some embodiments, the first condition can include one or more of the following:

[0263] a remaining time of the Re-Ordering Timer is less than or equal to a first threshold value;

[0264] a t-Reassembly timeout or not running;

[0265] a number of RoHC failures is greater than or equal to a second threshold value.

[0266] It should be noted that the number of RoHC failures can be one or multiple, and the embodiments of the present application do not limit this.

[0267] Further, the number of RoHC failures is configured by the network device; or,

[0268] the number of RoHC failures is configured by the network device; or,

[0269] the number of RoHC failures is determined by the receiving PDCP entity; or,

[0270] the number of RoHC failures is determined by the receiving PDCP entity and the sending PDCP entity.

[0271] In the case of Re-Ordering Timer timeout, the receiving PDCP entity can submit the data packet to the upper layer (such as the SDAP layer) of the PDCP layer.

[0272] In the case of Re-Ordering Timer timeout, the receiving PDCP entity can submit the data packet to the upper layer of the PDCP layer, and the receiving PDCP entity can consider (or determine) that the data packet with an SN number less than or equal to a third threshold value has been correctly received; wherein the third threshold value is the maximum SN number among the SN numbers of the data packets received by the receiving PDCP entity, or the maximum SN number among the SN numbers of the submitted data packets.

[0273] In the case that the receiving PDCP entity triggers the sending PDCP entity to perform data retransmission, the receiving PDCP entity sends retransmission indication information to the sending PDCP entity. Optionally, the retransmission indication information can be a PDCP status report.

[0274] In some embodiments, the PDCP status report is used to indicate one or more of the following:

[0275] the SN number and / or the COUNT value of the data packet that needs to be retransmitted;

[0276] the SN number and / or the COUNT value of the data packet that does not need to be retransmitted;

[0277] successful transmission or error transmission or unsuccessful transmission of the data packet;

[0278] successful reception or error reception or non-reception of the data packet;

[0279] transmission status of a lost packet;

[0280] transmission status of an unreceived packet;

[0281] transmission status or reception status of a received packet;

[0282] transmission status or reception status of a packet starting from the first packet with a reception status of NACK;

[0283] transmission status or reception status of a packet starting from the first packet with a reception status of ACK;

[0284] transmission status or reception status of a packet starting from the first lost packet;

[0285] retransmission granularity;

[0286] performing PDU retransmission, or the data packet requiring retransmission is a PDU;

[0287] performing SDU or SDU segment retransmission, or the data packet requiring retransmission is an SDU or an SDU segment.

[0288] Exemplarily, the content and / or Format of the PDCP status report can be similar to the PDCP status report in the related art.

[0289] (2) explicitly sending the behavior of the PDCP entity.

[0290] The sending PDCP entity receives the PDCP status report sent by the receiving PDCP entity, and performs data retransmission based on the PDCP status report.

[0291] In the case where the PDCP status report indicates the reception status and / or transmission status of a data packet, the sending PDCP entity retransmits one or more of the following data packets to the receiving PDCP entity:

[0292] an unreceived packet;

[0293] a packet with NACK;

[0294] a lost packet;

[0295] an incorrectly transmitted packet;

[0296] an incorrectly received packet;

[0297] an unsuccessfully transmitted packet.

[0298] It should be noted that, in the case that the PDCP status report indicates that the data packet is one or more of successful transmission, successful reception, and ACK, the sending PDCP entity can not retransmit the data packet to the receiving PDCP entity, and / or the sending PDCP entity can discard the data packet.

[0299] In the case that the PDCP status report indicates that the data packet to be retransmitted is a PDU, the sending PDCP entity retransmits the PDU to the receiving PDCP entity, or performs retransmission based on the PDU; and / or,

[0300] In the case that the PDCP status report indicates that the data packet to be retransmitted is an SDU or an SDU segment, the sending PDCP entity retransmits the SDU or the SDU segment to the receiving PDCP entity, or performs retransmission based on the SDU or the SDU segment.

[0301] The sending PDCP entity can determine whether to perform PDU-based or SDU-based retransmission based on the current PDCP state. For example, in the case that the PDCP layer is in a reestablishment state, the sending PDCP entity retransmits the SDU or the SDU segment to the receiving PDCP entity, or performs retransmission based on the SDU or the SDU segment; and / or,

[0302] In the case that the high layer of the PDCP layer indicates that the PDCP layer is reestablished, the sending PDCP entity retransmits the SDU or the SDU segment to the receiving PDCP entity, or performs retransmission based on the SDU or the SDU segment.

[0303] Embodiment two, the sending PDCP entity triggers data retransmission.

[0304] (1) Explicitly indicate the manner in which the sending PDCP entity triggers data retransmission.

[0305] Whether the sending PDCP entity triggers data retransmission can be configured by a network device, determined by the sending PDCP entity, determined according to a rule, specified by a protocol, or optional.

[0306] The sending PDCP entity can determine whether to trigger data retransmission based on a second condition.

[0307] In some embodiments, the second condition can be configured by a network device, specified by a protocol, determined by the sending PDCP entity, determined according to a rule, or specified by a protocol.

[0308] In some embodiments, the second condition can include one or more of the following:

[0309] The remaining time of the data packet is less than or equal to a fourth threshold value;

[0310] The remaining time of the PDCP Discard Timer is less than or equal to a fifth threshold value.

[0311] a remaining time of the data packet is less than or equal to a sixth threshold value, and the data packet is a data packet belonging to a first type;

[0312] a remaining time of the PDCP Discard Timer is less than or equal to a seventh threshold value, and the data packet is a data packet belonging to the first type;

[0313] a number of data packets without polling or a number of PDUs without carrying polling information is greater than or equal to an eighth threshold value;

[0314] a data amount of data packets without polling or a data amount of PDUs without carrying polling information is greater than or equal to a ninth threshold value;

[0315] a transmission buffer of the sending PDCP entity does not exist a PDU;

[0316] a t-PollRetransmit is timed out, the t-PollRetransmit is started after the sending PDCP entity sends a second PDU, and the second PDU includes a Polling field with a value of 1.

[0317] the data packet of the first type includes one or more of the following data packets:

[0318] a data packet belonging to a specific identifier;

[0319] a data packet belonging to a first DRB, and a logical channel priority of the first DRB is greater than or equal to a tenth threshold value;

[0320] a data packet belonging to a second DRB, and a reliability requirement corresponding to the second DRB is greater than or equal to an eleventh threshold value, or a reliability identifier of the second DRB is a specific identifier;

[0321] a data packet belonging to a third DRB, and an importance requirement corresponding to the third DRB is greater than or equal to a twelfth threshold value, or an importance identifier of the third DRB is a specific identifier;

[0322] a data packet belonging to a first PDU set, and a SN number of the first PDU set is a thirteenth threshold value, or other data packets with the same SN number as the first PDU set have been transmitted;

[0323] a data packet belonging to a second PDU set, and the data packet of the second PDU set is an Independent or independently decoded data packet, or an independent identifier or independently decoded identifier of the data packet of the second PDU set is a specific identifier;

[0324] a data packet belonging to a third PDU set, and an identifier of the third PDU set is greater than or equal to a fourteenth threshold value;

[0325] a data packet belonging to a first PDU set, and a data packet with a sequence number same as the first PDU set, wherein the data packet belongs to a first PDU set, and a data packet with a sequence number same as the first PDU set has been transmitted, and the remaining time of the data packet is less than or equal to a sixth threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data; and / or, the transmission time of the data packet is greater than or equal to a certain threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data.

[0326] a data packet belonging to a first PDU set, and a data packet with a sequence number same as the first PDU set, wherein the data packet belongs to a first PDU set, and a data packet with a sequence number same as the first PDU set has been transmitted, and the remaining time of the data packet is less than or equal to a sixth threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data; and / or, the transmission time of the data packet is greater than or equal to a certain threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data.

[0327] a data packet belonging to a first PDU set, and a data packet with a sequence number same as the first PDU set, wherein the data packet belongs to a first PDU set, and a data packet with a sequence number same as the first PDU set has been transmitted, and the remaining time of the data packet is less than or equal to a sixth threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data; and / or, the transmission time of the data packet is greater than or equal to a certain threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data.

[0328] a data packet belonging to a first PDU set, and a data packet with a sequence number same as the first PDU set, wherein the data packet belongs to a first PDU set, and a data packet with a sequence number same as the first PDU set has been transmitted, and the remaining time of the data packet is less than or equal to a sixth threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data; and / or, the transmission time of the data packet is greater than or equal to a certain threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data.

[0329] a data packet belonging to a first PDU set, and a data packet with a sequence number same as the first PDU set, wherein the data packet belongs to a first PDU set, and a data packet with a sequence number same as the first PDU set has been transmitted, and the remaining time of the data packet is less than or equal to a sixth threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data; and / or, the transmission time of the data packet is greater than or equal to a certain threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data.

[0330] a data packet belonging to a first PDU set, and a data packet with a sequence number same as the first PDU set, wherein the data packet belongs to a first PDU set, and a data packet with a sequence number same as the first PDU set has been transmitted, and the remaining time of the data packet is less than or equal to a sixth threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data; and / or, the transmission time of the data packet is greater than or equal to a certain threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data.

[0331] a data packet belonging to a first PDU set, and a data packet with a sequence number same as the first PDU set, wherein the data packet belongs to a first PDU set, and a data packet with a sequence number same as the first PDU set has been transmitted, and the remaining time of the data packet is less than or equal to a sixth threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data; and / or, the transmission time of the data packet is greater than or equal to a certain threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data.

[0332] a data packet belonging to a first PDU set, and a data packet with a sequence number same as the first PDU set, wherein the data packet belongs to a first PDU set, and a data packet with a sequence number same as the first PDU set has been transmitted, and the remaining time of the data packet is less than or equal to a sixth threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data; and / or, the transmission time of the data packet is greater than or equal to a certain threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data.

[0333] a data packet belonging to a first PDU set, and a data packet with a sequence number same as the first PDU set, wherein the data packet belongs to a first PDU set, and a data packet with a sequence number same as the first PDU set has been transmitted, and the remaining time of the data packet is less than or equal to a sixth threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data; and / or, the transmission time of the data packet is greater than or equal to a certain threshold value, the sending PDCP entity can send the receiving PDCP entity a retransmission data.

[0334] The data amount of the data packet without the probe or the data amount of the PDU without carrying the probe information is greater than or equal to a ninth threshold value (that is, if BYTE_WITHOUT_POLL >= pollByte, the Polling field with a value of 1 is included in the PDCP PDU corresponding to the PDCP SDU);

[0335] The transmission Buffer of the sending PDCP entity does not have the PDU (that is, if there is no data packet behind in the transmission Buffer, the Polling field with a value of 1 is included in the PDCP PDU corresponding to the PDCP SDU);

[0336] t-PollRetransmit expires, the fourth timer starts after the sending PDCP entity sends the second PDU, the second PDU includes the indication field with the first value (that is, if the Polling field with a value of 1 is included in the PDCP PDU corresponding to the PDCP SDU, t-PollRetransmit is started or restarted; in the case of t-PollRetransmit expires, the Polling field with a value of 1 is included in the PDCP PDU corresponding to the PDCP SDU);

[0337] There is a data packet with a delay or a remaining delay less than or equal to a certain threshold value.

[0338] (2) The behavior of the receiving PDCP entity is clarified.

[0339] The receiving PDCP entity can perform corresponding processing based on the behavior of the sending PDCP entity:

[0340] If the sending PDCP entity performs data retransmission, the receiving PDCP entity can receive the retransmitted data packet;

[0341] If the sending PDCP entity carries the Polling field with a value of 1 in the PDCP SDU (that is, the first PDU), the receiving PDCP entity triggers the PDCP status report and sends the PDCP status report to the sending PDCP entity. Correspondingly, the sending PDCP entity can perform data retransmission based on the PDCP status report.

[0342] It should be understood that in the embodiments of the present application, embodiment one and embodiment two can be used alone or in combination, and the embodiments of the present application do not limit this. Exemplarily, in the case of using embodiment one and embodiment two in combination, the receiving PDCP entity and the sending PDCP entity can both trigger data retransmission.

[0343] The embodiment of the present application provides a data retransmission method, data retransmission is performed between a receiving PDCP entity and a sending PDCP entity through a first protocol layer, and the first protocol layer has a data retransmission mechanism. In this way, data retransmission between the receiving PDCP entity and the sending PDCP entity can be implemented in one protocol layer, thereby simplifying a protocol stack, and enabling the data retransmission mechanisms of the PDCP layer and the RLC layer to be combined.

[0344] The preferred embodiments of the present application are described in detail above with reference to the drawings, but the present application is not limited to the specific details in the above-described embodiments, and various simple modifications can be made to the technical solutions of the present application within the technical concept of the present application, and the simple modifications all belong to the protection scope of the present application. For example, in the case where various specific technical features described in the above-described specific embodiments are combined in any appropriate manner without contradiction, in order to avoid unnecessary repetition, the present application does not further describe various possible combination manners. For another example, various different embodiments of the present application can also be combined in any manner, as long as the combination does not deviate from the idea of the present application, and the combination should also be regarded as the disclosed content of the present application. For another example, in the case where various embodiments described in the present application and / or technical features in various embodiments are combined with any prior art without contradiction, the technical solutions obtained after the combination should also fall within the protection scope of the present application.

[0345] It should also be understood that, in various method embodiments of the present application, the size of the serial number of the above-described processes does not mean the order of execution, and the execution order of the processes should be determined according to the functions and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0346] FIG. 5 is a structural composition schematic diagram of a data retransmission apparatus 500 provided by the embodiment of the present application, and the data retransmission apparatus 500 is applied to a receiving end, as shown in FIG. 5, and the data retransmission apparatus 500 can include:

[0347] The first communication unit 510 is configured to perform data retransmission between the receiving end through a first protocol layer, and the first protocol layer has a data retransmission mechanism.

[0348] In some embodiments, the first protocol layer replaces a packet data convergence protocol (PDCP) layer and / or a radio link control (RLC) layer; or the first protocol layer is the PDCP layer, and the RLC layer does not exist; or

[0349] The first protocol layer is the PDCP layer, and the RLC layer does not have a data retransmission mechanism; or

[0350] The first protocol layer has data retransmission mechanisms of the PDCP layer and the RLC layer, and the RLC layer does not exist; or the first protocol layer has data retransmission mechanisms of the PDCP layer and the RLC layer, and the RLC layer does not have data retransmission mechanisms.

[0351] In some embodiments, the data retransmission between the device and the sending end is triggered by the device based on a first condition; wherein whether to be triggered by the device and / or the triggering of the device is configured by a network device, determined by the device, determined according to a rule, or specified by a protocol.

[0352] In some embodiments, the first condition includes one or more of the following:

[0353] The remaining time of the first timer is less than or equal to a first threshold value;

[0354] The second timer is timed out or not running;

[0355] The number of compression or decompression failures is greater than or equal to a second threshold value.

[0356] In some embodiments, the number of compression or decompression failures is configured by a network device; or,

[0357] The number of compression or decompression failures is specified by a protocol; or,

[0358] The number of compression or decompression failures is determined by the device; or,

[0359] The number of compression or decompression failures is determined by the device and the sending end.

[0360] In some embodiments, the first communication unit 510 is further configured to submit a data packet to a higher layer of the first protocol layer in the case that the first timer is timed out.

[0361] In some embodiments, the data retransmission device 500 can further include:

[0362] The determining unit 520 is configured to determine that a data packet with a sequence number less than or equal to a third threshold value has been correctly received; wherein the third threshold value is the maximum sequence number among the sequence numbers of the data packets received by the device, or the maximum sequence number among the sequence numbers of the submitted data packets.

[0363] In some embodiments, the first timer is a reordering timer, the second timer is a reassembly timer, and the compression or decompression is robust header compression.

[0364] In some embodiments, the first communication unit 510 is further configured to receive a first protocol data unit (PDU) sent by the sending end; wherein the first PDU comprises an indication field with a first value, and the first PDU is used to indicate that the device triggers data retransmission with the sending end, or is used to trigger data retransmission between the device and the sending end.

[0365] In some embodiments, the first communication unit 510 is further configured to send a status report to the sending end, and the status report is used to indicate one or more of the following:

[0366] a transmission status of a data packet;

[0367] a reception status of a data packet;

[0368] a data packet that needs to be retransmitted.

[0369] In some embodiments, the status report indicates one or more of the following:

[0370] a sequence number and / or a count value of a data packet that needs to be retransmitted;

[0371] a sequence number and / or a count value of a data packet that does not need to be retransmitted;

[0372] a data packet that is successfully transmitted, or is unsuccessfully transmitted, or is not successfully transmitted;

[0373] a data packet that is successfully received, or is unsuccessfully received, or is not received;

[0374] a transmission status of a lost data packet;

[0375] a transmission status of a data packet that is not received;

[0376] a transmission status or a reception status of a received data packet;

[0377] a transmission status or a reception status of a data packet starting from a first data packet with a negative acknowledgement (NACK) reception status;

[0378] a transmission status or a reception status of a data packet starting from a first data packet with an acknowledgement (ACK) reception status;

[0379] a transmission status or a reception status of a data packet starting from a first lost data packet;

[0380] a retransmission granularity;

[0381] performing PDU retransmission, or a data packet that needs to be retransmitted is a PDU;

[0382] performing service data unit (SDU) or SDU segment retransmission, or a data packet that needs to be retransmitted is an SDU or an SDU segment.

[0383] In some embodiments, the data retransmission between the device and the sending end is triggered by the sending end based on a second condition; wherein whether to be triggered by the sending end and / or the triggering of the sending end is configured by a network device, determined by the sending end, determined according to a rule, or specified by a protocol.

[0384] In some embodiments, the second condition comprises one or more of the following:

[0385] a remaining time of the data packet is less than or equal to a fourth threshold value;

[0386] a remaining time of the third timer is less than or equal to a fifth threshold value;

[0387] a remaining time of the data packet is less than or equal to a sixth threshold value, and the data packet is a data packet belonging to a first type;

[0388] a remaining time of the third timer is less than or equal to a seventh threshold value, and the data packet is a data packet belonging to a first type;

[0389] a number of data packets without a probe or a number of PDUs without carrying a probe information is greater than or equal to an eighth threshold value;

[0390] a data amount of data packets without a probe or a data amount of PDUs without carrying a probe information is greater than or equal to a ninth threshold value;

[0391] a transmission buffer of the sending end does not exist a PDU;

[0392] a fourth timer expires, the fourth timer is started after the sending end sends a second PDU, and the second PDU comprises an indication field with a first value.

[0393] In some embodiments, the data packet of the first type comprises one or more of the following data packets:

[0394] a data packet belonging to a specific identifier;

[0395] a data packet belonging to a first data radio bearer (DRB), and a logical channel priority of the first DRB is greater than or equal to a tenth threshold value;

[0396] a data packet belonging to a second DRB, and a reliability requirement corresponding to the second DRB is greater than or equal to an eleventh threshold value, or a reliability identifier of the second DRB is a specific identifier;

[0397] a data packet belonging to a third DRB, and an importance requirement corresponding to the third DRB is greater than or equal to a twelfth threshold value, or an importance identifier of the third DRB is a specific identifier;

[0398] a data packet belonging to a first PDU set and a sequence number of the first PDU set being a thirteenth threshold value or another data packet having the same sequence number as the first PDU set having been transmitted;

[0399] a data packet belonging to a second PDU set and the data packet of the second PDU set being a standalone or standalone-decoded data packet or a standalone identifier or standalone-decoded identifier of the data packet of the second PDU set being a specific identifier;

[0400] a data packet belonging to a third PDU set and an identifier of the third PDU set being greater than or equal to a fourteenth threshold value;

[0401] a data packet having a reliability requirement greater than or equal to the eleventh threshold value or a reliability identifier being a specific identifier;

[0402] a data packet having an importance requirement greater than or equal to the twelfth threshold value or an importance identifier being a specific identifier;

[0403] a data packet having a sequence number greater than or equal to the thirteenth threshold value;

[0404] a standalone or standalone-decoded data packet or a data packet having a standalone identifier or standalone-decoded identifier being a specific identifier.

[0405] In some embodiments, the third timer is a discard timer and the fourth timer is a retransmission timer.

[0406] Embodiments of the present application provide a data retransmission apparatus, data retransmission between the apparatus and a sending end can be implemented at a protocol layer, thereby simplifying a protocol stack and enabling data retransmission mechanisms of a PDCP layer and an RLC layer to be combined.

[0407] Those skilled in the art should understand that the above description of the data retransmission apparatus of embodiments of the present application can be understood with reference to the description of the data retransmission method of embodiments of the present application.

[0408] FIG. 6 is a structural composition diagram of a data retransmission apparatus 600 provided by embodiments of the present application, which is applied to a sending end, as shown in FIG. 6, the data retransmission apparatus 600 can include:

[0409] a second communication unit 610 configured to perform data retransmission between the first protocol layer and a receiving end, the first protocol layer having a data retransmission mechanism.

[0410] In some embodiments, the first protocol layer replaces a packet data convergence protocol (PDCP) layer and / or a radio link control (RLC) layer; or the first protocol layer is the PDCP layer and the RLC layer does not exist; or the first protocol layer is the PDCP layer and the RLC layer exists and is configured to perform data retransmission between the first protocol layer and the receiving end.

[0411] The first protocol layer is the PDCP layer, and the RLC layer does not have a data retransmission mechanism; or

[0412] The first protocol layer has a data retransmission mechanism of the PDCP layer and the RLC layer, and the RLC layer does not exist; or the first protocol layer has a data retransmission mechanism of the PDCP layer and the RLC layer, and the RLC layer does not have a data retransmission mechanism.

[0413] In some embodiments, the data retransmission between the device and the receiving end is triggered by the receiving end based on a first condition; wherein whether to be triggered by the receiving end and / or the trigger of the receiving end is configured by a network device, determined by the receiving end, determined according to a rule or specified by a protocol.

[0414] In some embodiments, the first condition includes one or more of the following:

[0415] The remaining time of the first timer is less than or equal to a first threshold value;

[0416] The second timer is timed out or not running;

[0417] The number of compression or decompression failures is greater than or equal to a second threshold value.

[0418] In some embodiments, the number of compression or decompression failures is configured by a network device; or,

[0419] The number of compression or decompression failures is specified by a protocol; or,

[0420] The number of compression or decompression failures is determined by the receiving end; or,

[0421] The number of compression or decompression failures is determined by negotiation between the receiving end and the device.

[0422] In some embodiments, the first timer is a reordering timer, the second timer is a reassembly timer, and the compression or decompression is robust header compression.

[0423] In some embodiments, the second communication unit 610 is further configured to send a first protocol data unit (PDU) to the receiving end; wherein the first PDU includes an indication field with a first value, and the first PDU is used to indicate the receiving end to trigger data retransmission between the device and the receiving end, or to trigger data retransmission between the receiving end and the device.

[0424] In some embodiments, the second communication unit 610 is further configured to send the first PDU to the receiving end based on one or more of the following:

[0425] the number of data packets without a probe or the number of PDUs without carrying probe information is greater than or equal to an eighth threshold value;

[0426] the data volume of data packets without a probe or the data volume of PDUs without carrying probe information is greater than or equal to a ninth threshold value;

[0427] there is no PDU in the transmission buffer of the apparatus;

[0428] a fourth timer expires, the fourth timer being started after the apparatus sends a second PDU, the second PDU including the indication field with the first value.

[0429] In some embodiments, the second communication unit 610 is further configured to receive a status report sent by the receiving end, the status report being used to indicate one or more of the following:

[0430] the transmission status of data packets;

[0431] the reception status of data packets;

[0432] data packets that need to be retransmitted.

[0433] In some embodiments, the status report indicates one or more of the following:

[0434] the sequence number and / or count value of data packets that need to be retransmitted;

[0435] the sequence number and / or count value of data packets that do not need to be retransmitted;

[0436] data packets that are successfully transmitted, or unsuccessfully transmitted, or not transmitted successfully;

[0437] data packets that are successfully received, or unsuccessfully received, or not received;

[0438] the transmission status of lost data packets;

[0439] the transmission status of data packets that are not received;

[0440] the transmission status or reception status of received data packets;

[0441] the transmission status or reception status of data packets starting from the first data packet with a negative acknowledgement (NACK) reception status;

[0442] the transmission status or reception status of data packets starting from the first data packet with an acknowledgement (ACK) reception status;

[0443] the transmission status or reception status of data packets starting from the first lost data packet;

[0444] retransmission granularity;

[0445] performing PDU retransmission, or the data packet requiring retransmission is a PDU;

[0446] performing service data unit, SDU, or SDU segment retransmission, or the data packet requiring retransmission is an SDU or an SDU segment.

[0447] In some embodiments, the second communication unit 610 is further configured to retransmit one or more of a PDU, an SDU, or an SDU segment to the receiving end.

[0448] In some embodiments, the second communication unit 610 is further configured to retransmit a PDU to the receiving end, or perform retransmission based on a PDU, in a case where the status report indicates that the data packet requiring retransmission is a PDU; and / or,

[0449] retransmit an SDU or an SDU segment to the receiving end, or perform retransmission based on an SDU or an SDU segment, in a case where the status report indicates that the data packet requiring retransmission is an SDU or an SDU segment.

[0450] In some embodiments, the second communication unit 610 is further configured to retransmit an SDU or an SDU segment to the receiving end, or perform retransmission based on an SDU or an SDU segment, in a case where the first protocol layer is in a reestablishment state; and / or,

[0451] retransmit an SDU or an SDU segment to the receiving end, or perform retransmission based on an SDU or an SDU segment, in a case where a higher layer of the first protocol layer indicates that the first protocol layer is reestablished.

[0452] In some embodiments, the second communication unit 610 is further configured to retransmit one or more of the following data packets to the receiving end in a case where the status report indicates a reception status and / or a transmission status of the data packet:

[0453] a data packet that has not been received;

[0454] a data packet for which a NACK is received;

[0455] a data packet that has been lost;

[0456] a data packet that has been transmitted in error;

[0457] a data packet that has been received in error;

[0458] a data packet that has not been successfully transmitted.

[0459] In some embodiments, the data retransmission between the apparatus and the receiving end is triggered by the apparatus based on a second condition; wherein whether to be triggered by the apparatus and / or the triggering of the apparatus is configured by a network device, determined by the apparatus, determined according to a rule, or specified by a protocol.

[0460] In some embodiments, the second condition comprises one or more of the following:

[0461] a remaining time of the data packet is less than or equal to a fourth threshold value;

[0462] a remaining time of the third timer is less than or equal to a fifth threshold value;

[0463] a remaining time of the data packet is less than or equal to a sixth threshold value, and the data packet is a data packet belonging to a first type;

[0464] a remaining time of the third timer is less than or equal to a seventh threshold value, and the data packet is a data packet belonging to a first type;

[0465] a number of data packets without a probe or a number of PDUs without carrying probe information is greater than or equal to an eighth threshold value;

[0466] a data amount of data packets without a probe or a data amount of PDUs without carrying probe information is greater than or equal to a ninth threshold value;

[0467] there is no PDU in a transmission buffer of the apparatus;

[0468] a fourth timer expires, the fourth timer being started after the apparatus sends a second PDU, the second PDU comprising an indication field with a first value;

[0469] In some embodiments, the data packet of the first type comprises one or more of the following data packets:

[0470] a data packet belonging to a specific identifier;

[0471] a data packet belonging to a first data radio bearer (DRB), and a logical channel priority of the first DRB being greater than or equal to a tenth threshold value;

[0472] a data packet belonging to a second DRB, and a reliability requirement corresponding to the second DRB being greater than or equal to an eleventh threshold value, or a reliability identifier of the second DRB being a specific identifier;

[0473] a data packet belonging to a third DRB, and an importance requirement corresponding to the third DRB being greater than or equal to a twelfth threshold value, or an importance identifier of the third DRB being a specific identifier;

[0474] a data packet belonging to the first PDU set and having a sequence number equal to a thirteenth threshold value, or another data packet having a sequence number equal to the sequence number of the first PDU set has been transmitted;

[0475] a data packet belonging to the second PDU set and being an independent or independently-decoded data packet, or having an independent or independently-decoded identifier being a specific identifier;

[0476] a data packet belonging to the third PDU set and having an identifier greater than or equal to a fourteenth threshold value;

[0477] a data packet having a reliability requirement greater than or equal to the eleventh threshold value, or having a reliability identifier being a specific identifier;

[0478] a data packet having an importance requirement greater than or equal to the twelfth threshold value, or having an importance identifier being a specific identifier;

[0479] a data packet having a sequence number greater than or equal to the thirteenth threshold value;

[0480] an independent or independently-decoded data packet, or a data packet having an independent or independently-decoded identifier being a specific identifier.

[0481] In some embodiments, the third timer is a discard timer, and the fourth timer is a retransmission timer.

[0482] The embodiments of the present application provide a data retransmission apparatus, and data retransmission between the apparatus and a receiving end can be implemented at one protocol layer, thereby simplifying a protocol stack and enabling data retransmission mechanisms of a PDCP layer and an RLC layer to be combined.

[0483] Those skilled in the art should understand that the above description of the data retransmission apparatus of the embodiments of the present application can be understood with reference to the description of the data retransmission method of the embodiments of the present application.

[0484] FIG. 7 is a structural composition diagram of a communication device provided by the embodiments of the present application. The communication device 700 can be a sending end or a receiving end. The communication device 700 shown in FIG. 7 can include a processor 710, a memory 720 and a transceiver 730, wherein:

[0485] The memory 720 is configured to store a computer program.

[0486] The processor 710 is connected with the memory 720, and is configured to call and run the computer program from the memory 720, so as to implement the method in the embodiments of the present application.

[0487] The transceiver 730, also referred to as a communication interface, is configured to receive and send information in the process of communicating with other external devices.

[0488] In some embodiments, the memory 720 can be a separate device independent of the processor 710, or can be integrated in the processor 710.

[0489] In some embodiments, the transceiver 730 can include an input interface. The processor 710 can control the input interface to communicate with other external devices, and specifically, can receive information or data sent by other external devices.

[0490] In some embodiments, the transceiver 730 can include an output interface. The processor 710 can control the output interface to communicate with other external devices, and specifically, can send information or data to other external devices.

[0491] In some embodiments, the transceiver 730 can include a transmitter and a receiver. The transceiver 730 can further include an antenna, and the number of antennas can be one or more.

[0492] In some embodiments, the communication device 700 can be applied to the receiving end of the embodiments of the present application, and the communication device 700 can implement the corresponding processes realized by the receiving end in the various methods of the embodiments of the present application. For the sake of brevity, details are not repeated here.

[0493] In some embodiments, the communication device 700 can be applied to the sending end of the embodiments of the present application, and the communication device 700 can implement the corresponding processes realized by the sending end in the various methods of the embodiments of the present application. For the sake of brevity, details are not repeated here.

[0494] FIG. 8 is a schematic structural diagram of a chip according to an embodiment of the present application. The chip 800 shown in FIG. 8 includes a processor 810. The processor 810 can call and run a computer program from a memory to implement the method in the embodiments of the present application.

[0495] In some embodiments, as shown in FIG. 8, the chip 800 can further include a memory 820. The processor 810 can call and run a computer program from the memory 820 to implement the method in the embodiments of the present application.

[0496] The memory 820 can be a separate device independent of the processor 810, or can be integrated in the processor 810.

[0497] In some embodiments, the chip 800 can further include an input interface 830. The processor 810 can control the input interface 830 to communicate with other devices or chips, and specifically, can acquire information or data sent by other devices or chips.

[0498] In some embodiments, the chip 800 can further include an output interface 840. The processor 810 can control the output interface 840 to communicate with other devices or chips, and specifically, can output information or data to other devices or chips.

[0499] In some embodiments, the chip can be applied to the sending end in the embodiments of the present application, and the chip can implement the corresponding procedures realized by the sending end in various methods of the embodiments of the present application. For brevity, details are not described herein.

[0500] In some embodiments, the chip can be applied to the receiving end in the embodiments of the present application, and the chip can implement the corresponding procedures realized by the receiving end in various methods of the embodiments of the present application. For brevity, details are not described herein.

[0501] It should be understood that the chip mentioned in the embodiments of the present application can also be referred to as a system chip, a system chip, a chip system or a system on chip, etc.

[0502] FIG. 9 is a schematic block diagram of a communication system according to an embodiment of the present application. As shown in FIG. 9, the communication system 900 includes a sending end 910 and a receiving end 920.

[0503] The sending end 910 can be used to implement the corresponding functions realized by the sending end in the above methods, and the receiving end 920 can be used to implement the corresponding functions realized by the receiving end in the above methods. For brevity, details are not described herein.

[0504] It should be understood that the processor of the embodiments of the present application can be an integrated circuit chip with processing capability. In the implementation process, each step of the method embodiments described above can be completed by integrated logic circuits or instructions in the form of software in the processor. The processor described above can be a general processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The disclosed methods, steps and logic block diagrams in the embodiments of the present application can be implemented or executed. The general processor can be a microprocessor or the processor can also be any conventional processor or the like. The steps of the method disclosed in conjunction with the embodiments of the present application can be directly embodied as a hardware coding processor for execution, or a combination of hardware and software modules in the coding processor for execution. The software module can be located in a random access memory, a flash memory, a read only memory, a programmable read only memory or an electrically erasable programmable memory, a register or other mature storage medium in the art. The storage medium is located in the storage, and the processor reads the information in the storage, and combines the hardware to complete the steps of the above method.

[0505] It is to be understood that the memory in the embodiments of the present application can be a volatile memory or a nonvolatile memory, or can include both volatile and nonvolatile memory. Among them, the nonvolatile memory can be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically EPROM (EEPROM), or a flash memory. The volatile memory can be a Random Access Memory (RAM) used as an external cache. By way of example, and not limitation, many forms of RAM can be used, such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous Dynamic RAM (SDRAM), Double Data Rate SDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and Direct Rambus RAM (DR RAM). It should be noted that the memory of the system and method described herein is intended to include, but not be limited to, these and any other suitable types of memory.

[0506] The embodiments of the present application also provide a computer readable storage medium, which stores a computer program. The computer program is executed by at least one processor to implement the method in the embodiments of the present application.

[0507] In some embodiments, the computer readable storage medium can be applied to the receiving end in the embodiments of the present application, and the computer program enables the computer to execute the corresponding procedures implemented by the receiving end in the various methods of the embodiments of the present application. For the sake of brevity, details are not repeated here.

[0508] In some embodiments, the computer readable storage medium can be applied to the sending end in the embodiments of the present application, and the computer program enables the computer to execute the corresponding procedures implemented by the sending end in the various methods of the embodiments of the present application. For the sake of brevity, details are not repeated here.

[0509] The embodiment of the present application further provides a computer program product, which comprises a computer storage medium storing a computer program, the computer program comprising instructions executable by at least one processor, and the instructions, when executed by the at least one processor, implement the method in the embodiment of the present application.

[0510] In some embodiments, the computer program product can be applied to the receiving end in the embodiment of the present application, and the computer program instructions enable the computer to perform the corresponding procedures implemented by the receiving end in the various methods of the embodiment of the present application, which will not be repeated here for brevity.

[0511] In some embodiments, the computer program product can be applied to the sending end in the embodiment of the present application, and the computer program instructions enable the computer to perform the corresponding procedures implemented by the sending end in the various methods of the embodiment of the present application, which will not be repeated here for brevity.

[0512] The embodiment of the present application further provides a computer program, which enables the computer to perform the method in the embodiment of the present application.

[0513] In some embodiments, the computer program can be applied to the receiving end in the embodiment of the present application, and when the computer program runs on the computer, enables the computer to perform the corresponding procedures implemented by the receiving end in the various methods of the embodiment of the present application, which will not be repeated here for brevity.

[0514] In some embodiments, the computer program can be applied to the sending end in the embodiment of the present application, and when the computer program runs on the computer, enables the computer to perform the corresponding procedures implemented by the sending end in the various methods of the embodiment of the present application, which will not be repeated here for brevity.

[0515] Those skilled in the art can clearly understand that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are performed in hardware or software mode depends on the specific application and design constraints of the technical solution. The skilled person can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0516] Those skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working processes of the above-described system, device and unit can refer to the corresponding processes in the foregoing method embodiments, which will not be repeated here.

[0517] In several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other manners. For example, the described device embodiments are merely schematic. The division of the units is merely logical function division. There can be another division manner for the actual implementation, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections can be indirect couplings or communication connections through some interfaces, devices or units, and can be in electrical, mechanical or other forms.

[0518] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., can be located in one place, or can be distributed on multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0519] In addition, each functional unit in the various embodiments of the present application can be integrated into a processing unit, or each unit can be a physically independent unit, or two or more units can be integrated into one unit.

[0520] If the functions are realized in the form of software function units and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application or the part of the technical solutions that essentially contribute to the prior art can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, ROM, RAM, magnetic disk or optical disk, and various program code storage media.

[0521] The above is merely specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for data retransmission, the method comprising: receiving, by a receiving end, data retransmission between the receiving end and a sending end via a first protocol layer, the first protocol layer having a data retransmission mechanism. 2.The method of claim 1, wherein: the first protocol layer replaces a packet data convergence protocol (PDCP) layer and / or a radio link control (RLC) layer; or the first protocol layer is a PDCP layer, and an RLC layer is absent; or the first protocol layer is a PDCP layer, and the RLC layer does not have a data retransmission mechanism; or the first protocol layer has a data retransmission mechanism of a PDCP layer and an RLC layer, and the RLC layer is absent; or the first protocol layer has a data retransmission mechanism of a PDCP layer and an RLC layer, and the RLC layer does not have a data retransmission mechanism. 3.The method of claim 1 or 2, wherein: the data retransmission between the receiving end and the sending end is triggered by the receiving end based on a first condition; wherein whether to be triggered by the receiving end and / or the triggering of the receiving end is configured by a network device, determined by the receiving end, determined according to a rule, or specified by a protocol.

4. The method of claim 3, wherein, the first condition comprises one or more of: a remaining time of a first timer is less than or equal to a first threshold value; a second timer expires or is not running; a number of compression or decompression failures is greater than or equal to a second threshold value. 5.The method of claim 4, wherein: the number of compression or decompression failures is configured by a network device; or the number of compression or decompression failures is specified by a protocol; or the number of compression or decompression failures is determined by the receiving end; or the number of compression or decompression failures is determined by negotiation between the receiving end and the sending end.

6. The method of claim 4 or 5, wherein, further comprising: in the case where the first timer expires, the receiving end submits a data packet to a higher layer of the first protocol layer.

7. The method of claim 6, wherein, further comprising: the receiving end determines that a data packet with a sequence number less than or equal to a third threshold value has been correctly received; wherein the third threshold value is a maximum sequence number among sequence numbers of data packets received by the receiving end, or a maximum sequence number among sequence numbers of submitted data packets. 8.The method of any one of claims 4 to 7, wherein: the first timer is a reordering timer, the second timer is a reassembly timer, and the compression or decompression is robust header compression.

9. The method of any one of claims 1 to 8, wherein, further comprising: the receiving end receives a first protocol data unit (PDU) sent by the sending end; wherein the first PDU comprises an indication field with a first value, and the first PDU is used to indicate that the receiving end triggers data retransmission between the receiving end and the sending end, or is used to trigger data retransmission between the receiving end and the sending end.

10. The method of any one of claims 3 to 9, wherein, further comprising: the receiving end sends a status report to the sending end, the status report being used to indicate one or more of: a transmission status of a data packet; a reception status of a data packet; a data packet that needs to be retransmitted.

11. The method of claim 10, wherein, the status report indicates one or more of: a sequence number and / or a count value of a data packet that needs to be retransmitted; a sequence number and / or a count value of a data packet that does not need to be retransmitted; a data packet is successfully transmitted, or unsuccessfully transmitted, or unsuccessfully received; a data packet is successfully received, or unsuccessfully received; a transmission status of a lost data packet; a transmission status of an unsuccessfully received data packet; a transmission status or a reception status of a received data packet; a transmission status or a reception status of a data packet starting from a first data packet with a negative acknowledgement (NACK) as the reception status; a transmission status or a reception status of a data packet starting from a first data packet with an acknowledgement (ACK) as the reception status; a transmission status or a reception status of a data packet starting from a first lost data packet; a retransmission granularity; performing a PDU retransmission, or a data packet to be retransmitted is a PDU; performing a service data unit (SDU) or SDU segment retransmission, or a data packet to be retransmitted is an SDU or an SDU segment.

12. The method of any one of claims 1 to 11, wherein, The data retransmission between the receiving end and the sending end is triggered by the sending end based on a second condition; whether triggered by the sending end and / or the triggering of the sending end is configured by a network device, determined by the sending end, determined according to a rule, or specified by a protocol.

13. The method of claim 12, wherein, The second condition includes one or more of the following: a remaining time of a data packet is less than or equal to a fourth threshold value; a remaining time of a third timer is less than or equal to a fifth threshold value; a remaining time of a data packet is less than or equal to a sixth threshold value, and the data packet is a data packet belonging to a first type; a remaining time of the third timer is less than or equal to a seventh threshold value, and the data packet is a data packet belonging to the first type; a number of data packets without a probe or a number of PDUs without carrying a probe information is greater than or equal to an eighth threshold value; a data amount of data packets without a probe or a data amount of PDUs without carrying a probe information is greater than or equal to a ninth threshold value; there is no PDU in a transmission buffer of the sending end; a fourth timer is timed out, the fourth timer is started after the sending end sends a second PDU, and the second PDU includes an indication field with a first value.

14. The method of claim 13, wherein, The data packet of the first type includes one or more of the following data packets: a data packet belonging to a specific identifier; a data packet belonging to a first data radio bearer (DRB), and a logical channel priority of the first DRB is greater than or equal to a tenth threshold value; a data packet belonging to a second DRB, and a reliability requirement corresponding to the second DRB is greater than or equal to an eleventh threshold value, or a reliability identifier of the second DRB is a specific identifier; a data packet belonging to a third DRB, and an importance requirement corresponding to the third DRB is greater than or equal to a twelfth threshold value, or an importance identifier of the third DRB is a specific identifier; a data packet belonging to a first PDU set, and a sequence number of the first PDU set is a thirteenth threshold value, or other data packets with the same sequence number as the first PDU set have been transmitted; a data packet belonging to a second PDU set, and the data packet of the second PDU set is an independent or independently decoded data packet, or an independent identifier or independently decoded identifier of the data packet of the second PDU set is a specific identifier; a data packet belonging to a third PDU set, and an identifier of the third PDU set is greater than or equal to a fourteenth threshold value; a data packet belonging to a reliability requirement greater than or equal to the eleventh threshold value or a reliability identifier being a specific identifier; a data packet belonging to an importance requirement greater than or equal to the twelfth threshold value or an importance identifier being a specific identifier; a data packet belonging to a sequence number greater than or equal to the thirteenth threshold value; a data packet belonging to independence or independent decoding or an independence identifier or independent decoding identifier being a specific identifier.

15. The method of claim 13 or 14, wherein, the third timer is a discard timer and the fourth timer is a retransmission timer.

16. A data retransmission method, the method comprising: a sending end performing data retransmission with a receiving end through a first protocol layer, the first protocol layer having a data retransmission mechanism.

17. The method of claim 16, wherein, the first protocol layer replaces a packet data convergence protocol (PDCP) layer and / or a radio link control (RLC) layer; or, the first protocol layer is a PDCP layer and an RLC layer is absent; or, the first protocol layer is a PDCP layer and the RLC layer does not have a data retransmission mechanism; or, the first protocol layer has a data retransmission mechanism of a PDCP layer and an RLC layer and the RLC layer is absent; or, the first protocol layer has a data retransmission mechanism of a PDCP layer and an RLC layer and the RLC layer does not have a data retransmission mechanism.

18. The method of claim 16 or 17, wherein, the data retransmission between the sending end and the receiving end is triggered by the receiving end based on a first condition; wherein whether to be triggered by the receiving end and / or the triggering of the receiving end is configured by a network device, determined by the receiving end, determined according to a rule or specified by a protocol. the first condition comprises one or more of:

19. The method of claim 18, wherein, a remaining time of a first timer being less than or equal to a first threshold value; a second timer being timed out or not running; a number of compression or decompression failures being greater than or equal to a second threshold value.

20. The method of claim 19, wherein, the number of compression or decompression failures is configured by a network device; or, the number of compression or decompression failures is specified by a protocol; or, the number of compression or decompression failures is determined by the receiving end; or, the number of compression or decompression failures is determined by negotiation between the receiving end and the sending end.

21. The method of claim 19 or 20, wherein, the first timer is a reordering timer, the second timer is a reassembly timer, and the compression or decompression is robust header compression. further comprising:

22. The method of any one of claims 16 to 21, wherein, the sending end sending a first protocol data unit (PDU) to the receiving end, wherein the first PDU comprises an indication field with a first value, and the first PDU is used to instruct the receiving end to trigger data retransmission with the sending end or to trigger data retransmission between the receiving end and the sending end. the sending end sending the first PDU to the receiving end comprises:

23. The method of claim 22, wherein, the sending end sending the first PDU to the receiving end based on one or more of: ​ The number of data packets without the probe or the number of PDUs without carrying the probe information is greater than or equal to the eighth threshold value; The data amount of data packets without the probe or the data amount of PDUs without carrying the probe information is greater than or equal to the ninth threshold value; There is no PDU in the transmission buffer of the sending end; A fourth timer is started after the sending end sends a second PDU, and the second PDU includes an indication field with the first value.

24. The method of any one of claims 18-23, wherein, Further comprising: The sending end receives the status report sent by the receiving end, and the status report is used to indicate one or more of the following: The transmission status of the data packet; The receiving status of the data packet; The data packet that needs to be retransmitted.

25. The method of claim 24, wherein, The status report indicates one or more of the following: The sequence number and / or count value of the data packet that needs to be retransmitted; The sequence number and / or count value of the data packet that does not need to be retransmitted; The data packet is successfully transmitted, or is not successfully transmitted; The data packet is successfully received, or is not successfully received; The transmission status of the lost data packet; The transmission status of the un-received data packet; The transmission status or receiving status of the received data packet; The transmission status or receiving status of the data packet starting from the first data packet with a negative acknowledgement (NACK) receiving status; The transmission status or receiving status of the data packet starting from the first data packet with an acknowledgement (ACK) receiving status; The transmission status or receiving status of the data packet starting from the first lost data packet; The retransmission granularity; The PDU retransmission is performed, or the data packet that needs to be retransmitted is the PDU; The service data unit (SDU) or SDU segment retransmission is performed, or the data packet that needs to be retransmitted is the SDU or SDU segment.

26. The method of claim 24 or 25, wherein, Further comprising: The sending end retransmits one or more of the PDU, SDU, and SDU segment to the receiving end.

27. The method of claim 26, wherein, The sending end retransmits one or more of the PDU, SDU, and SDU segment to the receiving end, including: In a case where the status report indicates that the data packet that needs to be retransmitted is the PDU, the sending end retransmits the PDU to the receiving end, or performs the retransmission based on the PDU; and / or, In a case where the status report indicates that the data packet that needs to be retransmitted is the SDU or SDU segment, the sending end retransmits the SDU or SDU segment to the receiving end, or performs the retransmission based on the SDU or SDU segment. The sending end retransmits one or more of the PDU, SDU, and SDU segment to the receiving end, including:

28. The method of claim 26 or 27, wherein, In a case where the first protocol layer is in a reestablishment state, the sending end retransmits the SDU or SDU segment to the receiving end, or performs the retransmission based on the SDU or SDU segment; and / or, In a case where a higher layer of the first protocol layer indicates that the first protocol layer is reestablished, the sending end retransmits the SDU or SDU segment to the receiving end, or performs the retransmission based on the SDU or SDU segment. Further comprising:

29. The method of any one of claims 24 to 28, wherein, In a case where the status report indicates the receiving status and / or transmission status of the data packet, the sending end retransmits one or more of the following data packets to the receiving end: The un-received data packet; The data packet with the NACK receiving status; The lost data packet; The data packet with the error transmission status; The data packet with the error receiving status; a data packet received in error; a data packet not transmitted successfully.

30. The method of any one of claims 16 to 29, wherein, The data retransmission between the sending end and the receiving end is triggered by the sending end based on a second condition; wherein whether to be triggered by the sending end and / or the triggering of the sending end is configured by a network device, determined by the sending end, determined according to a rule, or specified by a protocol.

31. The method of claim 30, wherein, The second condition includes one or more of the following: a remaining time of the data packet is less than or equal to a fourth threshold value; a remaining time of the third timer is less than or equal to a fifth threshold value; a remaining time of the data packet is less than or equal to a sixth threshold value, and the data packet is a data packet belonging to a first type; a remaining time of the third timer is less than or equal to a seventh threshold value, and the data packet is a data packet belonging to the first type; a number of data packets without a probe or a number of PDUs without carrying a probe information is greater than or equal to an eighth threshold value; a data amount of data packets without a probe or a data amount of PDUs without carrying a probe information is greater than or equal to a ninth threshold value; there is no PDU in a transmission buffer of the sending end; a fourth timer is timed out, the fourth timer is started after the sending end sends a second PDU, and the second PDU includes an indication field with a first value.

32. The method of claim 31, wherein, The data packet of the first type includes one or more of the following data packets: a data packet belonging to a specific identifier; a data packet belonging to a first data radio bearer (DRB), and a logical channel priority of the first DRB is greater than or equal to a tenth threshold value; a data packet belonging to a second DRB, and a reliability requirement corresponding to the second DRB is greater than or equal to an eleventh threshold value, or a reliability identifier of the second DRB is a specific identifier; a data packet belonging to a third DRB, and an importance requirement corresponding to the third DRB is greater than or equal to a twelfth threshold value, or an importance identifier of the third DRB is a specific identifier; a data packet belonging to a first PDU set, and a sequence number of the first PDU set is a thirteenth threshold value, or other data packets with the same sequence number as the first PDU set have been transmitted; a data packet belonging to a second PDU set, and the data packet of the second PDU set is an independent or independent decoding data packet, or an independent identifier or independent decoding identifier of the data packet of the second PDU set is a specific identifier; a data packet belonging to a third PDU set, and an identifier of the third PDU set is greater than or equal to a fourteenth threshold value; a data packet with a reliability requirement greater than or equal to the eleventh threshold value or a reliability identifier being a specific identifier; a data packet with an importance requirement greater than or equal to the twelfth threshold value or an importance identifier being a specific identifier; a data packet with a sequence number greater than or equal to the thirteenth threshold value; an independent or independent decoding data packet, or a data packet with an independent identifier or independent decoding identifier being a specific identifier.

33. The method of claim 31 or 32, wherein The third timer is a discard timer, and the fourth timer is a retransmission timer.

34. A data retransmission apparatus, the apparatus comprising: The first communication unit is configured to perform data retransmission between the sending end and the receiving end through a first protocol layer, wherein the first protocol layer has a data retransmission mechanism.

35. A data retransmission apparatus, the apparatus comprising: The second communication unit is configured to perform data retransmission between the sending end and the receiving end through a first protocol layer, wherein the first protocol layer has a data retransmission mechanism.

36. A communication device, the communication device comprising: a memory for storing a computer program; a processor connected to the memory, for calling and running the computer program from the memory, to implement the method of any one of claims 1 to 15, or to implement the method of any one of claims 16 to 33; a transceiver for receiving and sending information in the process of transceiving information with other external devices.

37. A chip, the chip comprising: a memory for storing a computer program; a processor connected to the memory, for calling and running the computer program from the memory, to enable the device installed with the chip to perform the method of any one of claims 1 to 15, or to perform the method of any one of claims 16 to 33; a transceiver for receiving and sending information in the process of transceiving information with devices or chips.

38. A computer readable storage medium, the computer readable storage medium storing a computer program, the computer program being executed by at least one processor to implement the method of any one of claims 1 to 15, or to implement the method of any one of claims 16 to 33.

39. A computer program product comprising a computer program or instructions, the computer program or instructions being executed by a processor to implement the steps in the method of any one of claims 1 to 15; or to implement the steps in the method of any one of claims 16 to 33.

40. A computer program, the computer program enabling a computer to perform the method of any one of claims 1 to 15, or to implement the method of any one of claims 16 to 33. ​

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