Communication method and related device

Abstract

The present application pertains to the field of data processing, and provides a communication method and a related device. In the method, if a data packet to be dropped has been delivered to a lower layer, a sending end and / or a receiving end may drop said data packet. Moreover, after dropping said data packet, the sending end and / or the receiving end may also update in real time a transmission state parameter, such as a state parameter of a sending window, a state parameter of a receiving window, or a state parameter of a PDCP layer. In this way, it is possible to avoid transmission or retransmission of a data packet to be dropped, and avoid failure of the receiving end receiving data, which facilitates saving window resources and improving the quality of communication.

Description

A communication method and related equipment This application claims priority to the Chinese patent application filed with the China Patent Office on February 8, 2024, with application number 202410178018.4 and application name “A communication method and related equipment”, and the Chinese patent application filed with the China Patent Office on March 1, 2024, with application number 202410242792.7 and application name “A communication method and related equipment”, the entire contents of which are incorporated by reference into this application. Technical Field The present application relates to the field of communication technology, and in particular to a communication method and related equipment. Background Art Layer 2 (L2) of the new radio (NR) includes the service data adaptation protocol (SDAP), packet data convergence protocol (PDCP), radio link control (RLC), media access control (MAC), and physical (PHY) layers. Data generated by the application layer on the transmitting end is sequentially appended with header information from each layer to facilitate the implementation of each layer's functions. The RLC layer adds RLC header information to the PDCP protocol data unit (SDU) service data unit (SDU), encapsulating it into an RLC SDU. The SDU enters the RLC layer's transmit queue and is then delivered to the MAC layer. The MAC layer encapsulates the RLC SDU into a MAC SDU, which is then sent to the receiving end via the PHY layer. In some scenarios, some data packets can be discarded. After confirming that a certain part of the data packets needs to be discarded, the PDCP layer can transmit a request to the RLC layer to discard the part of the data packets. According to the relevant provisions of the protocol, the sequence number (SN) gap (SN gap) cannot be introduced in the SDU in the acknowledged mode (AM). That is to say, after the RLC layer receives the request to discard the part of the data packets, if the SDU corresponding to the part of the data packets has not been transmitted to the lower layer (such as the MAC layer and the physical layer), the RLC layer will directly discard the SDU corresponding to the part of the data packets. If the SDU corresponding to the part of the data packets has been transmitted to the lower layer, according to the provisions of the relevant protocol, the sending end cannot discard the SDU corresponding to the part of the data packets. This will cause a transmission window failure between the sending end and the receiving end, such as the sending end frequently retransmitting the SDU corresponding to the part of the data packets, and the receiving end's receiving window state parameters cannot be updated, resulting in a receiving window freeze. Summary of the Invention An embodiment of the present application provides a communication method and related equipment, which can update the transmission status parameters of the device based on discarded data packets. This method can avoid transmitting or retransmitting discarded data packets and avoid receiving window deadlock, which is conducive to improving communication efficiency and saving air interface resources. In a first aspect, a communication method is provided, which is applied to a transmitting end, and includes: determining discarded data packets; and updating a transmission state parameter of the transmitting end based on the discarded data packets. In this implementation, the sender can update its transmission state parameters, such as the send window state parameters, based on discarded packets. This prevents the sender from transmitting or retransmitting discarded packets even if they have already been delivered to lower layers, improving communication efficiency and conserving air interface resources. Optionally, the discarded data packet may be an SDU or protocol data unit of the RLC layer. In a possible implementation of the first aspect, the transmission state parameter of the transmitting end includes a first state parameter, and the first state parameter is used to indicate the sequence number of the next data packet to be confirmed for reception by the transmitting end. Optionally, the first state parameter may be the TX_Next_Ack parameter mentioned below. In a possible implementation of the first aspect above, the discarded data packet satisfies a first condition; the first condition includes: the discarded data packet is within the sending window; or the sequence number of the discarded data packet is between the sequence number indicated by the first status parameter and the sequence number of the next data packet sent by the sender; or the sequence number of the discarded data packet is greater than or equal to the sequence number indicated by the first status parameter; or the sequence number of the discarded data packet is less than or equal to the sequence number of the next data packet sent by the sender. In this implementation, the sequence number of the discarded data packet between the sequence number indicated by the first state parameter and the sequence number of the next data packet sent by the sender can be the sequence number indicated by the first state parameter < the sequence number of the discarded data packet < the sequence number of the next data packet sent by the sender, or the sequence number indicated by the first state parameter ≤ the sequence number of the discarded data packet ≤ the sequence number of the next data packet sent by the sender, or the sequence number indicated by the first state parameter ≤ the sequence number of the discarded data packet < the sequence number of the next data packet sent by the sender, or the sequence number indicated by the first state parameter < the sequence number of the discarded data packet ≤ the sequence number of the next data packet sent by the sender. Optionally, the first condition may be, for example, a discarding condition corresponding to the RLC layer of the transmitting end described below. In a possible implementation of the first aspect above, the above-mentioned updating of the transmission status parameters of the sending end based on the discarded data packets includes: when the discarded data packets meet the second condition, updating the transmission status parameters of the sending end based on the discarded data packets; wherein the second condition includes: the discarded data packet is within the sending window; or the sequence number of the discarded data packet is between the sequence number indicated by the first status parameter and the sequence number of the next data packet sent by the sending end; or the sequence number of the discarded data packet is greater than or equal to the sequence number indicated by the first status parameter; or the sequence number of the discarded data packet is less than or equal to the sequence number of the next data packet sent by the sending end. In this implementation, the sequence number of the discarded data packet between the sequence number indicated by the first state parameter and the sequence number of the next data packet sent by the sender can be the sequence number indicated by the first state parameter < the sequence number of the discarded data packet < the sequence number of the next data packet sent by the sender, or the sequence number indicated by the first state parameter ≤ the sequence number of the discarded data packet ≤ the sequence number of the next data packet sent by the sender, or the sequence number indicated by the first state parameter ≤ the sequence number of the discarded data packet < the sequence number of the next data packet sent by the sender, or the sequence number indicated by the first state parameter < the sequence number of the discarded data packet ≤ the sequence number of the next data packet sent by the sender. Optionally, the second condition may be, for example, an update condition corresponding to the RLC layer of the transmitting end described below. In a possible implementation of the first aspect above, the above-mentioned updating of the transmission state parameter of the sender based on the discarded data packets includes: when there is a first data packet whose sequence number is the same as the sequence number indicated by the first state parameter among the discarded data packets, updating the first state parameter to a second sequence number following the first sequence number of the first data packet; or, corresponding to the absence of a data packet whose sequence number is the same as the sequence number indicated by the first state parameter among the discarded data packets, when the first state parameter is updated to the first sequence number, updating the first state parameter to the second sequence number. In this implementation, if the second and first conditions described above do not exist, the sender may update the transmission state parameter of the send window if the sequence number indicated by the first state parameter is the same as the first sequence number of the first data packet among the discarded data packets. If there is no data packet among the discarded data packets with the same sequence number as the sequence number indicated by the first state parameter, the sender may wait until the first state parameter is updated to the first sequence number before updating the transmission state parameter of the send window. In this implementation, the first data packet may be any data packet among the discarded data packets. In a possible implementation of the first aspect, updating the transmission state parameter of the transmitting end based on the discarded data packet includes: When the sequence number indicated by the first state parameter is the same as the first sequence number of the first data packet among the discarded data packets, the first state parameter is updated to a second sequence number following the first sequence number, wherein the first data packet is the data packet with the smallest sequence number among the discarded data packets; or, when the sequence number indicated by the first state parameter is different from the first sequence number and the first state parameter is updated to the first sequence number, the first state parameter is updated to the second sequence number. In this implementation, retransmission of discarded data packets can be avoided, which is beneficial to communication quality and saves air interface resources. In a possible implementation of the first aspect, the second sequence number is not among the sequence numbers corresponding to the discarded data packets. In other words, the data packet corresponding to the second sequence number is not among the discarded data packets, or the data packet corresponding to the second sequence number is not discarded. In a possible implementation of the first aspect, the discarded data packets include first consecutive data packets, the first consecutive data packets include the first data packet, and the second sequence number is a sequence number of a second data packet following the first consecutive data packet. Optionally, the first continuous data packets may include N (N is an integer greater than or equal to 1) data packets, and the first data packet may be the first data packet of the first continuous data packets, or may be a data packet in the middle of the first continuous data packets. Optionally, the consecutive data packets may be data packets with consecutive sequence numbers. In a possible implementation of the first aspect above, the second data packet is the next data packet of the first continuous data packet, or the first data packet after the first continuous data packet that has not received confirmation feedback, or the first data packet after the first continuous data packet that has not received confirmation feedback and is not among the discarded data packets. In a possible implementation of the first aspect, the first sequence number and a third sequence number corresponding to the last data packet in the first consecutive data packets are maintained based on a first discard state parameter and a second discard state parameter, respectively. Optionally, the first discard state parameter may be TX_discard_low in the following text, and the discard state parameter may be TX_Discard_High in the following text. In a possible implementation of the first aspect, the method further includes: At least one consecutive data packet that is discarded is determined, and a first discard state parameter and a second discard state parameter are updated based on the at least one consecutive data packet that is discarded. In a possible implementation of the first aspect, a maximum value of sequence numbers corresponding to at least one consecutive data packet is a fourth sequence number, a minimum value is a fifth sequence number, and the fourth sequence number is greater than or equal to the fifth sequence number; and updating a first discard state parameter and a second discard state parameter based on the at least one consecutive discarded data packet includes: Corresponding to the fourth sequence number being less than the first discard state parameter, updating the first discard state parameter to the fifth sequence number and updating the second discard state parameter to the fourth sequence number; or corresponding to the fourth sequence number being greater than the second discard state parameter, and the fifth sequence number being greater than or equal to the first discard state parameter and less than or equal to the second discard state parameter, updating the second discard state parameter to the fourth sequence number; or corresponding to the fourth sequence number being less than or equal to the second discard state parameter and greater than or equal to the first state parameter, and the fifth sequence number being less than the first discard state parameter, updating the first discard state parameter to the fifth sequence number; or corresponding to the fourth sequence number being less than or equal to the second discard state parameter and greater than or equal to the first state parameter, and the fifth sequence number being less than the first discard state parameter, updating the first discard state parameter to the fifth sequence number; Alternatively, if the fourth sequence number and the fifth sequence number are between the first discard state parameter and the second discard state parameter, or the fifth sequence number is greater than the second discard state parameter, the first discard state parameter and the second discard state parameter are not updated. In a possible implementation of the first aspect, the method further includes: Send discard information to the receiving end, which is used to indicate the discarded data packets. In this implementation, after receiving the discard information, the receiving end may discard the discarded data packet based on the discarded data packet indicated by the discard information, the transmission state parameter of the receiving end, and / or the discarded data packet. In a possible implementation of the first aspect, the method further includes: receiving first indication information; The discarded data packet is discarded in response to the first indication information. In this implementation, before determining the discarded data packet or during the process of determining the discarded data packet, the sending end may discard the discarded data packet if it receives the first indication information. In other words, if the sending end does not receive the first indication information, it will not discard the discarded data packet. In a possible implementation of the first aspect, the method further includes: determining at least one consecutive data packet that is discarded, wherein the maximum value of sequence numbers in the at least one consecutive data packet is the fourth sequence number, the minimum value is the fifth sequence number, and the fourth sequence number is greater than or equal to the fifth sequence number; and corresponding to the fourth sequence number being less than the first discard state parameter, updating the first discard state parameter to the fifth sequence number and updating the second discard state parameter to the fourth sequence number; or corresponding to the fourth sequence number being greater than the second discard state parameter and the fifth sequence number being greater than or equal to the first discard state parameter and less than or equal to the discard state parameter, updating the second discard state parameter to the fourth sequence number; or corresponding to the fourth sequence number being less than or equal to the second discard state parameter and greater than or equal to the first state parameter and the fifth sequence number being less than the first discard state parameter, updating the first discard state parameter to the fifth sequence number; or corresponding to the fourth sequence number being less than or equal to the second discard state parameter and greater than or equal to the first state parameter and the fifth sequence number being less than the first discard state parameter, updating the first discard state parameter to the fifth sequence number; or corresponding to the fourth sequence number being less than or equal to the second discard state parameter and greater than or equal to the first state parameter and the fifth sequence number being less than the first discard state parameter, updating the first discard state parameter to the fifth sequence number; or corresponding to the fourth sequence number being less than or equal to the second discard state parameter and greater than or equal to the first state parameter and the fifth sequence number being less than the first discard state parameter, not updating the first discard state parameter and the second discard state parameter. In a possible implementation of the first aspect, the method further includes: sending discard information to the receiving end, where the discard information is used to indicate the discarded data packet. In a possible implementation of the first aspect, the determining of the discarded data packets includes: receiving first indication information, and determining the discarded data packets in response to the first indication information. In this implementation, the first indication information can be used to enable or disable the function of the transmitting end determining the discarded data packets and updating the transmission state parameters of the receiving end based on the discarded data packets. The transmitting end can determine the discarded data packets and update the transmission state parameters of the receiving end based on the discarded data packets only when the first indication information is received to enable the function. In a second aspect, a communication method is provided, which is applied to a receiving end, and the method includes: determining discarded data packets; and updating a transmission state parameter of the receiving end based on the discarded data packets. In this implementation, the receiving end can update its transmission state parameters, such as receive window state parameters and PDCP layer state parameters, based on discarded packets. This prevents the transmitting end from transmitting or retransmitting discarded packets, even if they have already been delivered to lower layers, and prevents receive window freezes, thereby improving communication efficiency and conserving air interface resources. In a possible implementation of the second aspect above, the transmission status parameter of the above-mentioned receiving end includes at least one of the following parameters: a second status parameter, the second status parameter is used to indicate the sequence number of the next data packet of the data packet that the receiving end has most recently received in sequence and in full; a third status parameter, the third status parameter is used to indicate the sequence number of the next data packet of the data packet that the receiving end has most recently received in full; and a fourth status parameter, the fourth status parameter is used to indicate the next sequence number of the sequence number corresponding to the data packet that triggers the reassembly timer. Optionally, the second status parameter may be RX_Next hereinafter, the third status parameter may be RX_Highest_Status hereinafter, and the fourth status parameter may be RX_Next_Status_Trigger hereinafter. In a possible implementation of the second aspect above, the above-mentioned updating of the transmission state parameters of the receiving end based on the discarded data packets includes: when the discarded data packets meet the third condition, updating the transmission state parameters of the receiving end based on the discarded data packets; wherein the third condition includes: the discarded data packet is within the receiving window; or the sequence number of the discarded data packet is between the sequence number indicated by the second state parameter and the sequence number indicated by the third state parameter; or the sequence number of the discarded data packet is between the sequence number indicated by the second state parameter and the sequence number indicated by the third state parameter; or the sequence number of the discarded data packet is between the sequence number indicated by the second state parameter and the sequence number indicated by the fourth state parameter; or the sequence number of the discarded data packet is greater than or equal to the sequence number indicated by the second state parameter; or the sequence number of the discarded data packet is less than or equal to the maximum sequence number of the sequence numbers of the data packets that have been completely received by the receiving end; or the sequence number of the discarded data packet is less than or equal to the sequence number indicated by the third state parameter; or the sequence number of the discarded data packet is less than or equal to the sequence number indicated by the fourth state parameter. In this implementation, the receiving end updates the transmission status parameters of the receiving end only when the discarded data packet meets the third condition, and there is no need to update the transmission status parameters of the receiving end when the discarded data packet does not meet the third condition. This can reduce the overhead of maintaining the transmission status parameters of the receiving end. In a possible implementation of the second aspect above, the above-mentioned updating of the transmission state parameter of the receiving end based on the discarded data packets includes: when there is a third data packet whose sequence number is the same as the sequence number indicated by the second state parameter among the discarded data packets, updating the second state parameter to the seventh sequence number after the sixth sequence number of the third data packet; or, corresponding to the fact that there is no data packet whose sequence number is the same as the sequence number indicated by the second state parameter among the discarded data packets, when the second state parameter is updated to the sixth sequence number, updating the second state parameter to the seventh sequence number. In this implementation, if the third condition does not exist, the receiving end may update the transmission state parameter of the receive window if the sequence number indicated by the second state parameter is the same as the sixth sequence number of the third data packet among the discarded data packets. If there is no data packet among the discarded data packets with the same sequence number as the sequence number indicated by the second state parameter, the receiving end may wait until the second state parameter is updated to the sixth sequence number before updating the transmission state parameter of the receive window. In this implementation, the third data packet can be any one of the discarded data packets. In a possible implementation of the second aspect, updating the transmission state parameter of the receiving end based on the discarded data packet includes: If the sequence number indicated by the second state parameter is the same as the sixth sequence number of the third data packet among the discarded data packets, updating the second state parameter to the seventh sequence number following the sixth sequence number, wherein the third data packet is the data packet with the smallest sequence number among the discarded data packets; Alternatively, if the sequence number indicated by the second state parameter is different from the sixth sequence number, and the second state parameter is updated to the sixth sequence number, the second state parameter is updated to the seventh sequence number. In a possible implementation of the second aspect, the discarded data packets include a second consecutive data packet, the second consecutive data packet includes a third data packet, and the seventh sequence number is a sequence number of a fourth data packet after the second consecutive data packet. Optionally, the second continuous data packets may include N (N is an integer greater than or equal to 1) data packets, and the third data packet may be the first data packet of the second continuous data packets, or may be a data packet in the middle of the second continuous data packets. In a possible implementation of the second aspect, the seventh sequence number is not among the sequence numbers corresponding to the discarded data packets. In other words, the data packet corresponding to the seventh sequence number is not among the discarded data packets, or the data packet corresponding to the seventh sequence number is not discarded. In a possible implementation of the second aspect above, the fourth data packet is the next data packet of the second continuous data packet, or the first incompletely received data packet after the second continuous data packet, or the first incompletely received data packet after the second continuous data packet that is not among the discarded data packets. In a possible implementation of the second aspect, the discarded data packets include second consecutive data packets, and the second consecutive data packets include third data packets; and updating the transmission state parameters of the receiving end based on the discarded data packets further includes: If the sequence number of the last data in the second continuous data packet is greater than or equal to the sequence number indicated by the third state parameter, updating the third state parameter to an eighth sequence number; and / or when the sequence number of the last data in the second continuous data packet is greater than or equal to the sequence number corresponding to the fourth state parameter, updating the fourth state parameter to a sequence number next to the largest sequence number among the sequence numbers of the data packets completely received by the receiving end; The eighth sequence number is the sequence number of the fifth data packet after the second consecutive data packet, and the fifth data packet is the next data packet after the second consecutive data packet, or the first incompletely received data packet after the second consecutive data packet. In a possible implementation of the second aspect, the method further includes: A status report is sent to the sending end, where the status report is used to indicate that all data packets in the second consecutive data packets have been completely received by the receiving end. In a possible implementation of the second aspect, the sending of the report to the transmitting end includes: In a case where the acknowledgement feedback ACK of one or more data packets in the second continuous data packets is not sent to the sending end, a status report is sent to the sending end, where the status report includes the ACK of the one or more data packets. In a possible implementation of the second aspect, the sixth sequence number and the ninth sequence number corresponding to the last data packet in the second consecutive data packets are maintained based on the third discard state parameter and the fourth discard state parameter, respectively. Optionally, the third discard state parameter may be RX_discard_low in the following text, and the fourth discard state parameter may be RX_Discard_High in the following text. In a possible implementation of the second aspect, the method further includes: At least one consecutive data packet that is discarded is determined, and a third discard state parameter and a fourth discard state parameter are updated based on the at least one consecutive data packet that is discarded. In a possible implementation of the second aspect, a maximum value of sequence numbers corresponding to the at least one consecutive data packet is the tenth sequence number, a minimum value is the eleventh sequence number, and the tenth sequence number is greater than or equal to the eleventh sequence number. Furthermore, updating a third discard state parameter and a fourth discard state parameter based on the at least one consecutive discarded data packet includes: Corresponding to the tenth sequence number being less than the third discard state parameter, the third discard state parameter is updated to the eleventh sequence number, and the fourth discard state parameter is updated to the tenth sequence number; or corresponding to the tenth sequence number being greater than the fourth discard state parameter, and the eleventh sequence number being greater than or equal to the third discard state parameter and less than or equal to the discard state parameter, updating the fourth discard state parameter to the tenth sequence number; or corresponding to the tenth sequence number being less than or equal to the fourth discard state parameter and greater than or equal to the third state parameter, and the eleventh sequence number being less than the third discard state parameter, updating the third discard state parameter to the eleventh sequence number; or corresponding to the tenth sequence number being less than or equal to the fourth discard state parameter and greater than or equal to the third state parameter, and the eleventh sequence number being less than the third discard state parameter, updating the third discard state parameter to the eleventh sequence number; Alternatively, corresponding to the tenth sequence number and the eleventh sequence number being between the third discard state parameter and the fourth discard state parameter, or the eleventh sequence number being greater than the fourth discard state parameter, the third discard state parameter and the fourth discard state parameter are not updated. In a possible implementation of the second aspect, the receiving end includes a radio link control layer, and the radio link control layer: determines discarded data packets; and updates a transmission state parameter of the receiving end based on the discarded data packets. In a possible implementation of the second aspect, the transmission status parameter of the receiving end includes at least one of the following parameters: A fifth status parameter, where the fifth status parameter is used to indicate a COUNT value corresponding to the first data packet that the PDCP layer of the receiving end has not submitted to an upper layer of the PDCP layer; The sixth state parameter is used to indicate the COUNT value corresponding to the data packet that triggers the reassembly timer of the PDCP layer. In a possible implementation of the second aspect, updating a transmission state parameter of the receiving end using the discarded data packet includes: When the discarded data packet meets the fourth condition, the transmission status parameter of the receiving end is updated based on the discarded data packet, wherein the fourth condition includes: the COUNT value corresponding to the discarded data packet is between the COUNT value indicated by the fifth status parameter and the COUNT value corresponding to the next data packet received at the PDCP layer; or the COUNT value corresponding to the discarded data packet is greater than or equal to the COUNT value indicated by the fifth status parameter; or the COUNT value corresponding to the discarded data packet is less than or equal to the COUNT value corresponding to the next data packet received at the PDCP layer. In a possible implementation of the second aspect above, the above-mentioned updating of the transmission status parameters of the receiving end based on the discarded data packets includes: in a case where there is a sixth data packet whose COUNT value is the same as the COUNT value indicated by the fifth status parameter among the discarded data packets, updating the fifth status parameter to a second COUNT value after the first COUNT value of the sixth data packet; or, corresponding to the fact that there is no data packet whose COUNT value is the same as the COUNT value indicated by the fifth status parameter among the discarded data packets, in a case where the fifth status parameter is updated to the first COUNT value, updating the fifth status parameter to the second COUNT value. In this implementation, if the fourth condition does not exist, the receiving end may update the transmission state parameter of the receive window if the COUNT value indicated by the fifth state parameter is the same as the first COUNT value of the sixth packet among the discarded packets. If there is no packet among the discarded packets whose COUNT value is the same as the COUNT value indicated by the first state parameter, the receiving end may wait until the fifth state parameter is updated to the first COUNT value before updating the transmission state parameter of the receive window. In this implementation, the sixth packet can be any one of the discarded packets. In a possible implementation of the second aspect, updating the transmission state parameter of the receiving end based on the discarded data packet includes: When the COUNT value indicated by the fifth state parameter is the same as the first COUNT value of the sixth data packet among the discarded data packets, the fifth state parameter is updated to a second COUNT value after the first COUNT value, wherein the sixth data packet is the data packet with the smallest COUNT value among the discarded data packets; or, when the COUNT value indicated by the fifth state parameter is different from the first COUNT value, when the fifth state parameter is updated to the first COUNT value, the fifth state parameter is updated to the second COUNT value. In a possible implementation of the second aspect, the discarded data packets include third consecutive data packets, the third consecutive data packets include a sixth data packet, and the second COUNT value is a COUNT value of a seventh data packet after the sixth data packet. Optionally, the third consecutive data packets may include Q data packets, where Q is an integer greater than or equal to 1. The sixth data packet may be the first data packet of the third consecutive data packets, or may be a data packet in the middle of the third consecutive data packets. In a possible implementation of the second aspect, the second COUNT value is not included in the COUNT values corresponding to the discarded data packets. In a possible implementation of the second aspect above, the seventh data packet is the next data packet of the third consecutive data packet, or the first data packet after the third consecutive data packet that is not submitted to the upper layer of the PDCP layer, or the first data packet after the third consecutive data packet that is not submitted to the upper layer of the PDCP layer and is not among the discarded data packets. In a possible implementation of the second aspect, updating the transmission state parameter of the receiving end based on the discarded data packet further includes: When the second COUNT value is greater than the COUNT value indicated by the sixth state parameter, the sixth state parameter is updated to the COUNT value corresponding to the next data packet received by the PDCP layer. And / or start the reassembly timer of the PDCP layer. In a possible implementation of the second aspect, the first COUNT value and the third COUNT value corresponding to the last data packet in the third consecutive data packets are maintained based on the fifth discard state parameter and the sixth discard state parameter, respectively. Optionally, the fifth discard state parameter may be PDCPRX_discard_low in the following text, and the sixth discard state parameter may be PDCPRX_Discard_High in the following text. In a possible implementation of the second aspect, the method further includes: Determine at least one consecutive data packet to be discarded, where a maximum value of COUNT values corresponding to the at least one consecutive data packet is a fourth COUNT value, a minimum value is a fifth COUNT value, and the fourth COUNT value is greater than or equal to the fifth COUNT value; If the fourth COUNT value is less than the fifth discard state parameter, the fifth discard state parameter is updated to the fifth COUNT value and the sixth discard state parameter is updated to the fourth COUNT value. or corresponding to the fourth COUNT value being greater than the fifth discard state parameter, and the fifth COUNT value being greater than or equal to the fifth discard state parameter and less than or equal to the sixth discard state parameter, updating the sixth discard state parameter to the fourth COUNT value; or corresponding to the fourth COUNT value being less than or equal to the sixth discard state parameter and greater than or equal to the fifth state parameter, and the fifth COUNT value being less than the fifth discard state parameter, updating the fifth discard state parameter to the fifth COUNT value; or corresponding to the fourth COUNT value being less than or equal to the sixth discard state parameter and greater than or equal to the fifth state parameter, and the fifth COUNT value being less than the fifth discard state parameter, updating the fifth discard state parameter to the fifth COUNT value; Alternatively, corresponding to the fourth COUNT value and the fifth COUNT value being between the fifth discard state parameter and the sixth discard state parameter, or the fifth COUNT value being greater than the sixth discard state parameter, the fifth discard state parameter and the sixth discard state parameter are not updated. In a possible implementation of the second aspect, the determining of the discarded data packet includes: receiving discard information indicating the discarded data packet. In this implementation, the receiving end may determine the discarded data packet indicated by the discard information as the discarded data packet. In a possible implementation of the second aspect, the PDCP layer: determines discarded data packets; and updates the transmission state parameters of the receiving end based on the discarded data packets. In a third aspect, a sending device is provided, comprising: one or more processors; one or more memories; the one or more memories storing one or more computer programs, the one or more computer programs comprising instructions, which, when executed by the one or more processors, enable the terminal device to execute the method described in any one of the implementation methods of the first to third aspects above. In a fourth aspect, a communication system is provided, comprising a transmitting device and a receiving device, wherein the transmitting device is used to execute the method described in any implementation manner in the above-mentioned first aspect, and the receiving device is used to execute the method described in any implementation manner in the above-mentioned second aspect. In a fifth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer-executable program instructions. When the computer-executable program instructions are executed on a computer, the computer executes the method described in any one of the implementation methods of the first to second aspects above. In a sixth aspect, a computer program product is provided, which includes a computer program code. When the computer program code is run on a computer, the computer is caused to execute the method described in any one of the implementation methods of the first to second aspects above. It should be understood that the beneficial effects of the third to sixth aspects mentioned above can be referred to the description of the first and second aspects, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS FIG1A shows a schematic diagram of a user plane protocol architecture according to some embodiments of the present application. FIG1B shows a schematic diagram of a process of transmitting a protocol data unit set from a sending end to a receiving end according to some embodiments of the present application. FIG2 shows a schematic diagram of a control plane protocol architecture according to some embodiments of the present application. FIG3 shows a schematic diagram of a sending window according to some embodiments of the present application. FIG4 shows a schematic diagram of a receiving window according to some embodiments of the present application. FIG5 shows a schematic diagram of state parameters of a PDCP layer according to some embodiments of the present application. FIG6A is a schematic diagram showing a process of a transmitting end sending a data packet according to some embodiments of the present application. FIG6B is a schematic diagram showing a process of a receiving end receiving a data packet according to some embodiments of the present application. FIG7A is a schematic diagram showing the relationship between data packet A and a sending window according to some embodiments of the present application. FIG7B shows a schematic diagram of the relationship between data packet A and a receiving window according to some embodiments of the present application. 8A to 8D are schematic diagrams illustrating the relationship between some discarded data packets and the sending window according to some embodiments of the present application. 9A to 9E are schematic diagrams showing some scenarios of updating the discard window of the sending end according to some embodiments of the present application. FIG10A shows a schematic diagram of updating transmission parameters of a receiving end according to some embodiments of the present application. FIG10B shows another schematic diagram of updating transmission parameters at a receiving end according to some embodiments of the present application. 11A to 11G are schematic diagrams showing some scenarios of updating a discard window at a receiving end according to some embodiments of the present application. 12A to 12C are schematic diagrams illustrating some state parameters of an updating receiving window according to some embodiments of the present application. 13A and 13B are schematic diagrams illustrating some updating of PDCP layer status parameters according to some embodiments of the present application. FIG. 14A to FIG. 14E are schematic diagrams showing some scenarios of updating the PDCP discard window according to some embodiments of the present application. Figure 15A shows a schematic diagram of a network-side device sending first indication information to a user equipment according to some embodiments of the present application. Figure 15B shows a schematic diagram of a PDCP layer sending first indication information to an RLC layer according to some embodiments of the present application. Figure 15C shows a schematic diagram of a MAC layer sending first indication information to an RLC layer according to some embodiments of the present application. FIG16 shows a schematic diagram of an interaction process of a communication method according to some embodiments of the present application. FIG17 shows a schematic diagram of an interaction process of another communication method according to some embodiments of the present application. FIG18 is a flow chart showing a communication method according to some embodiments of the present application. FIG19 is a flow chart showing another communication method according to some embodiments of the present application. FIG20 is a flow chart showing another communication method according to some embodiments of the present application. FIG21 shows a schematic diagram of a system architecture according to some embodiments of the present application. FIG22 shows a schematic structural diagram of a transmitting end device 00 according to some embodiments of the present application. DETAILED DESCRIPTION It should be noted that the terms used in the implementation methods section of the embodiments of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application. In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B; "and / or" in this article is merely a way to describe the association relationship of associated obstacles, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more than two, "at least one" and "one or more" mean one, two or more than two. In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly specifying the number of the technical features indicated. Therefore, the definition of "first" and "second" features may explicitly or implicitly include one or more of the features. References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in yet other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized. In order to facilitate understanding of the communication method provided by the present application, the concepts or attributes that may be involved in the following embodiments are first introduced. 1. Protocol Data Unit Set According to the definition of SA, a protocol data unit set can be used as a data unit in the data transmission process. A protocol data unit set consists of one or more data packets, each of which can carry a payload that constitutes an information unit. The application layer at the receiving end can obtain a complete information unit based on the payload carried by all protocol data units (PDU) in a protocol data unit set, such as the information corresponding to a video frame or a picture frame. In an embodiment of the present application, the data unit may include a frame and a video slice. Among them, the frame can be understood as a carrier of transmitted data, and the video slice can be understood as a specific type of data unit in a video service. From the perspective of the carrier of transmitted data, in some cases, a protocol data unit set can correspond to a frame; from the perspective of the type of transmitted data, in some cases, in a video service, the data carried by a protocol data unit set can correspond to a video slice. Generally speaking, the application layer at the receiving end needs to receive all packets in the protocol data unit set to obtain a complete information unit. Discarding one or more packets may result in the receiving end not being able to obtain the entire information unit. However, in some cases, the application layer at the receiving end can also use certain algorithms to calculate the discarded data based on the data of the obtained PDU. In this way, even if some (such as a small number or less important) PDUs are discarded, the application layer at the receiving end can still recover all or part of the information unit. SA proposed the concept of PDU set, which is defined as follows: PDU Set: A PDU Set is composed of one or more PDUs carrying the payload of one unit of information generated at the application level (ega frame or video slice for XRM Services, as used in TR 26.926

[0027] ).In some implementations all PDUs in a PDU Set are needed by the application layer to use the corresponding unit of information.In other implementations,the application layer can still recover parts all or of the information unit,when some PDUs are missing. That is, a PDU set consists of one or more PDUs, which carry the payload of an information unit generated by the application layer, such as a frame or a video slice. The above definition shows that in some implementations, the application layer needs to receive all PDUs in a PDU set to obtain the information unit; in another implementation, when some PDUs are discarded, the application layer can still recover all or part of the information unit. A protocol data unit set can be used as a data unit, which can specifically correspond to a frame or a video slice. A protocol data unit set includes multiple data packets, each of which has a serial number (such as PDU SN) that is different from other data packets, and the payloads carried by the multiple data packets can constitute information units (such as a video frame, a picture, etc.). Different protocol data unit sets can be set with different importance levels. For example, a protocol data unit set with a high importance level can be used to transmit frames of high importance, and a protocol data unit set with a low importance level can be used to transmit frames of low importance, thereby realizing the separate transmission of frames of different importance so that these frames can be processed differently later. For the same set of payloads, the data packets divided at different layers may be different, and the number and sequence numbers of data packets at different layers may also be different. For ease of description, in the following embodiments, the sequence number of the RLC layer data packet (e.g., RLC SDU or RLC PDU) is referred to as the RLC SN, and the sequence number of the PDCP layer data packet (e.g., PDCP SDU or PDCP PDU) is referred to as the PDCP SN. 2. User Plane Protocol Architecture 1A , the user plane protocol architecture may include an SDAP layer, a PDCP layer, an RLC layer, a MAC layer, and a physical layer. Referring to Figure 1B , based on the user plane protocol architecture of Figure 1A , the process of transmitting a data packet containing a set of protocol data units from a transmitter to a receiver may include: the SDAP layer obtains the IP data packet transmitted by its upper layer (application layer or transport layer), performs radio bearer (RB) processing on the IP data packet, and generates a data packet including a header and a physical portion SDAP SDU (i.e., payload). This data packet may be marked as an SDAP PDU data packet. The SDAP layer then transmits the SDAP PDU data packet to the PDCP layer. After obtaining the SDAP PDU data packet, the PDCP layer processes the data packet according to the PDCP protocol, generating a data packet including a header H and a physical portion PDCP SDU (including the SDAP SDU and the SDAP layer header). This data packet may be marked as a PDCP PDU data packet. The PDCP layer then further transmits the PDCP PDU data packet to the RLC layer. After the RLC layer obtains the PDCP PDU packet, it processes it according to the RLC protocol, generating a packet including a header (H) and a physical portion (RLC SDU) (including the PDCP SDU and the PDCP layer header). This packet can be marked as an RLC PDU packet. The RLC layer then transmits the RLC PDU packet to the MAC layer. After the MAC layer obtains the RLC PDU packet, it processes it according to the MAC protocol, generating a packet including a header (H) and a physical portion (MAC SDU) (including the RLC SDU and the RLC layer header). This packet can be marked as a MAC PDU packet. Following this process, the MAC layer can obtain multiple MAC PDU packets corresponding to a data unit. Based on these MAC PDU packets, the MAC layer can ultimately obtain a MAC PDU transport block containing multiple data packets. The MAC layer can then transmit the generated MAC PDU transport block to the receiving end using air interface resources. After receiving the PDU, the receiving end can parse the PDU according to the reverse process of generating the PDU, so that the application layer of the receiving end can obtain the data carried by all PDUs in the PDU set based on the parsed results, and then obtain the information unit based on the payload carried by all PDUs. The specific method and process for parsing the data in the PDU set by the receiving end can be set according to the relevant protocol or actual needs. 3. Control Plane Protocol Architecture Referring to Figure 2, in the control plane protocol framework, the user equipment (UE) side may include the non-access stratum (NAS) layer, radio resource control (RRC) layer, PDCP layer, RLC layer, MAC layer and PHY layer; the gNB side may include the RRC layer, PDCP layer, RLC layer, MAC layer and PHY layer; the access and mobility management function (AMF) side may include the NAS layer. The NAS layer can be used for UE mobility and session management procedures, and to establish and maintain IP connections between the UE and the PDN GW. The main services and functions of the RRC layer include broadcasting system information related to the Non-Access Stratum (NAS), paging, establishment, maintenance, and release of RRC connections between the UE and the E-UTRAN, security functions including key management, establishment, configuration, maintenance, and release of point-to-point radio bearers, broadcasting system messages of the NAS and AS layers, paging functions, establishment, maintenance, and release of RRC connections, establishment, modification, and release of end-to-end radio bearers, and mobility management including UE measurement reporting, cell handover, and UE cell selection and reselection. The RRC layer protocol terminates at the eNode B. The PDCP layer can be used to send or receive packet data to or from a peer PDCP entity. For example, the PDCP layer can compress and decompress IP headers, encrypt data and signaling, and protect signaling integrity. The RLC layer is responsible for segmentation and concatenation, error correction, retransmission processing, and sequential transmission of higher-layer data. The RLC layer operates in three modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). AM mode is used for TCP services such as file transfer; UM mode allows higher-layers to provide sequential data transmission; and TM mode can be used for specialized purposes such as random access. The MAC layer is used for mapping between logical channels and transport channels, scheduling and assigning priorities to logical channels based on QoS, and processing HARQ retransmission and uplink and downlink scheduling. The PHY layer handles coding, modulation and demodulation, multi-antenna mapping, and other telecommunication physical layer functions. 4. Send window: Referring to Figure 3, the state parameters of the sending window may include but are not limited to TX_Next_Ack, TX_Next, and AM_Window_Size. TX_Next_Ack: This state variable holds the value of the SN of the next RLC SDU for which apositive acknowledgment is to be received in-sequence, and it serves as the lower edge of the transmitting window. It is initially set to 0, and is updated whenever the AM RLC entity receives a positive acknowledgment for an RLC SDU with SN=TX_Next_Ack. The TX_Next_Ack state variable is the SN of the next packet after the acknowledgment packet received in sequence, which is the lower boundary of the transmit window. Once a packet with the SN of TX_Next_Ack is received, TX_Next_Ack needs to be updated. It can also be understood that TX_Next_Ack is the RLC SN of the RLC SDU to be received. RLC SDUs corresponding to RLC SNs less than this value have been confirmed received by the receiving end. The initial value is 0, which is the lower boundary of the sending window. In addition, the upper boundary of the sending window is TX_Next_Ack + AM_Window_Size; TX_Next: This newly state variable holds the value of the SN to be assigned for the next generated AMD PDU. It is initially set to 0, and is updated whenever the AM RLC entity constructs an AMD PDU with SN=TX_Next and contains an RLC SDU or the last segment of a RLC SDU. The TX_Next state variable is the SN of the next newly generated AMD PDU. It is updated once the AM RLC entity constructs an AMD PDU with the SN number TX_Next, which includes an RLC SDU or a segment of an RLC SDU. The TX_Next state variable can also be understood as the RLC SN of the RLC SDU to be transmitted, or the maximum RLC SN of the transmitted RLC SDUs + 1, or the RLC SN of the most recently generated RLC SDU. If the SN of the RLC SDU generated by the AM RLC entity is equal to TX_Next, TX_Next is updated. The initial value of TX_Next is 0. AM_Window_Size: AM window size. When using a 12-bit SN, the size is 2048; when using an 18-bit SN, the size is 131072. It should be understood that the status parameters of the sending window may also include PDU_WITHOUT_POLL, BYTE_WITHOUT_POLL, RETX_COUNT, t_PollRetransmit, etc. For details, please refer to the relevant protocols and will not be described here. 5. Receive Window Referring to FIG4 , the status parameters of the receive window may include but are not limited to: RX_Next, RX_Next_Highest, AM_Window_Size, RX_Highest_Status, and RX_Next_Status_Trigger. RX_Next: This state variable holds the value of the SN following the last in-sequence completely received RLC SDU, and it serves as the lower edge of the receiving window. It is initially set to 0, and is updated whenever the AM RLC entity receives an RLC SDU with SN=RX_Next. The RX_Next state variable is the SN next to the SN of the most recently received RLC SDU in sequence and is the lower boundary of the receive window. It is updated whenever the AM RLC entity receives a packet with the SN RX_Next. It can also be understood that RX_Next is the RLC SN of the next RLC SDU to be received. RLC SDUs with RLC SNs less than this value have all been completely received, which is the lower boundary of the receive window. If the RLC SN of the RLC SDU received by the AM RLC entity is the same as RX_Next, RX_Next can be updated. The upper boundary of the receive window is RX_Next + AM_Window_Size; RX_Next_Highest: This state variable holds the value of the SN following the SN of the RLC SDU with the highest SN among received RLC SDUs.It is initially set to 0. The RX_Next_Highest state variable is the next SN after the highest SN in the received RLC SDU. It is the maximum RLC SN of the currently received RLC SDU + 1. The initial value of RX_Next_Highest is 0. AM_Window_Size: AM window size. When using a 12-bit SN, the size is 2048; when using an 18-bit SN, the size is 131072. RX_Highest_Status: This state variable holds the highest possible value of the SN which can be indicated by "ACK_SN" when a STATUS PDU needs to be constructed. It is initially set to 0. The RX_Highest_Status status variable is the highest possible SN number when the status PDU needs to be constructed. This SN number can be indicated as "ACK_SN (acknowledgement feedback)". Alternatively, RX_Highest_Status can be understood as the maximum RLC SN of the RLC SDUs that were completely received when the status report was sent. It is updated when the t-Reassembly timer expires or the received RLC SN equals its value. Alternatively, RX_Highest_Status can be the sequence number of the packet following the most recently completely received packet at the receiving end. RX_Next_Status_Trigger: This state variable holds the value of the SN following the SN of the RLC SDU which triggered t-Reassembly. RX_Next_Status_Trigger is the next SN of the RLC SDU that triggers the reassembly timer. It can also be understood as the value of RX_Next_Highest when the timer t-Reassembly times out. t-Reassembly: Reassembly timer, which sends a status report when it times out. The actual timeout period may depend on the specific implementation and is continuously started in a loop. t-StatusProhibit: The status report prohibition timer starts after the status report is sent. The status report can be sent only after the timeout. It should be understood that the status parameters of the receiving window may also include t-Reassembly, t-StatusProhibit, etc. For details, please refer to the relevant protocols and will not be described in detail here. 6.PDCP layer status parameters 5 , the status parameters of the PDCP receiving end may include RX_NEXT, RX_DELIV, and RX_REORD, etc. RX_NEXT, This state variable indicates the COUNT value of the next PDCP SDU expected to be received. The initial value is 0. RX_NEXT indicates the COUNT value of the next PDCP SDU expected to be received. It can also be understood that RX_NEXT indicates the COUNT value of the next PDCP SDU that the PDCP needs to receive. RX_DELIV, This state variable indicates the COUNT value of the first PDCP SDU not delivered to the upper layers, but still waited for.The initial value is 0. RX_DELIV indicates the COUNT value of the first PDCP SDU that has not yet been submitted to the upper layer (e.g., SDAP layer). Its initial value is 0. RX_REORD, This state variable indicates the COUNT value following the COUNT value associated with the PDCP Data PDU which triggered t-Reordering. For target SRB configured with state variables continuation, the initial value is the value stored in PDCP entity for the corresponding source SRB. RX_REORD indicates the COUNT value of PDCP DATA PDUs that trigger the reassembly timer. What is needed is that at the PDCP layer, packets are identified based on the COUNT value. The existing SA protocol defines the COUNT value as follows: The COUNT value is composed of a HFN and the PDCP SN. The size of the HFN part in bits is equal to 32 minus the length of the PDCP SN. For MRBs, an HFN with a reference SN can be provided by upper layers. If provided, the initial value of the HFN is set according to the HFN and the reference SN. Otherwise, the initial value of the HFN is set by the UE implementation. It can be understood that the COUNT value may include a hyperframe number (HFN) and a PDCP SN. The size of the HFN portion (e.g., in bits) may be equal to 32 minus the length of the PDCP SN. The COUNT value may be used in the PDCP layer to maintain data integrity and perform encryption / decryption operations. The technical solution of this application is described below with reference to the accompanying drawings. The current protocol description of RLC responding to upper layer (e.g., PDCP) layer instructions to discard RLC SDUs may include: Description 1: When indicated from upper layer (egPDCP) to discard a particular RLC SDU, the transmitting side of an AM RLC entity or the transmitting UM RLC entity shall discard the indicated RLC SDU, if neither the RLC SDU nor a segment thereof has been submitted to the lower layers. The transmitting side of an AM RLC entity shall not introduce an RLC SN gap when discarding an RLC SDU. Description 2: RLC-AM is useful to limit data loss, however RLC-AM feedback or retransmission triggering mechanisms are not well adapted for short packet delay budgets applicable to XR traffic. Also, for RLC AM, considered amounts of data may be in-flight, iein the window, and there is no current way to avoid retransmitting this data, even if the data is old. As described above, in the current protocol, after the RLC receives an instruction from the upper layer to discard a data packet (hereinafter referred to as a "to-be-discarded data packet"), if the RLC SDU or RLC SDU segment corresponding to the to-be-discarded data packet has not been transmitted to the lower layers (e.g., the MAC layer and the PHY layer), the RLC may discard the SDU or RLC SDU segment. If the to-be-discarded data packet has already been delivered to the lower layers, the RLC will not discard the to-be-discarded data packet. This will cause the transmitter to retransmit the to-be-discarded data packet, wasting transmission resources. For example, referring to FIG6A , assuming that the transmitter first transmits the RLC SDUs corresponding to SN0 to SN7, then TX_Next_Ack = SN0 and TX_Next = SN8. If the status report (SR) received by the transmitter indicates that the receiver has completely received the RLC SDUs corresponding to SN0, SN1, and SN7, and has incompletely received (not received or incompletely received) the RLC SDUs corresponding to SN2 to SN6, the transmitter may initially transmit the RLC SDU corresponding to SN8 and retransmit the RLC SDUs corresponding to SN2 to SN6, and update TX_Next_Ack to SN2 and TX_Next to SN9. If the transmitter determines that the RLC SNs of the RLC SDUs corresponding to the packets to be discarded are SN2 to SN6, since the RLC SDUs corresponding to SN2 to SN6 are within the transmit window and have been submitted to the lower layer, according to the protocol, the transmitter cannot discard the RLC SDUs corresponding to SN2 to SN6. The RLC SDU1 corresponding to SN2 to SN6 has not been fully sent to the receiving end, and the transmitting end still needs to continue to retransmit the RLC SDU corresponding to SN2 to SN6. Accordingly, referring to Figure 6B, after receiving the SDU corresponding to SN0 and SN1, the receiving end can update RX_Next from SN0 to SN2. At this time, RX_Next_Highest is SN8. After receiving the RLC SDU corresponding to SN7, the receiving end can send an SR to the transmitting end indicating that the RLC SDU corresponding to SN0, SN1, and SN7 has been completely received, and the RLC SDU corresponding to SN2-SN6 has not been completely received, and wait for the RLC SDU corresponding to SN2 to be retransmitted. This affects the data transmission efficiency between the transmitting end and the receiving end. In view of this, the present application provides a communication method, in which a device (such as a transmitting end or a receiving end) can discard a data packet after determining that the data packet is to be discarded, and update the transmission status parameters (such as the status parameters of the transmitting end's sending window, the status parameters of the receiving end's receiving window, the status parameters of the receiving end's PDCP layer, etc.) after the data packet is discarded to improve the communication quality between devices. In some embodiments, the data packet to be discarded may be an SDU or a PDU, which is not limited here. In some embodiments, the data packets to be discarded may be data packets of the RLC layer, data packets of the PDCP layer, or data packets of other layers, which are not limited here. For ease of understanding, first introduce: Conditions for packet discard In some embodiments, a device (e.g., a transmitting end) discards data packet A (data packet to be discarded) according to a first condition. The discard condition may be whether data packet A is within a transmission window, or further may be whether the SN corresponding to data packet A is within the transmission window. The transmission window may be a window corresponding to or reported by the sending window, or a window corresponding to or included in the receiving window. For example, using the RLC protocol layer as an example, packet A is a packet that the RLC protocol layer has already delivered to a lower layer (e.g., the MAC protocol layer). Packet A is a packet that the PDCP layer sends to the RLC and needs to be discarded. Therefore, the transmitting RLC layer discards the packet that has been delivered to the lower layer to avoid retransmission of the packet, which would otherwise waste resources. For example, if packet A is within the transmission window, the device can discard packet A. If packet A is not within the transmission window, the device does not need to discard packet A, that is, it does not need to take any action. Because packets outside the transmission window do not require maintenance, they do not need to be processed. In some embodiments, corresponding to the RLC layer of the transmitting end, data packet A may be an RLC SDU or an RLC PDU. A discard condition may include that the first RLC SN corresponding to data packet A satisfies the following conditions: TX_Next_Ack ≤ first RLC SN ≤ TX_Next. The transmitting end may discard data packet A if the first RLC SN satisfies TX_Next_Ack ≤ first RLC SN ≤ TX_Next; otherwise, no processing is performed. For example, referring to Figure 7A , assuming the lower boundary of the transmit window is SN2, the upper boundary of the transmit window is SN2049, and TX_Next = SN7. If the first RLC SN is less than SN2 (e.g., SN0) or greater than SN7 (e.g., SN8), the discard condition is determined not to be met and no processing is performed. If the first RLC SN is greater than or equal to SN2 and less than or equal to SN7, or greater than SN7 (e.g., SN8), the transmitter may determine that the discard condition is met and discard packet A. In other embodiments, corresponding to the RLC layer of the transmitting end, the discard condition may further include other conditions, for example, the first RLC SN corresponding to the data packet A satisfies: TX_Next_Ack≤first RLC SN, or the first RLC SN≤TX_Next. In some embodiments, corresponding to the RLC layer of the receiving end, the discard condition may include that the first RLC SN corresponding to data packet A satisfies the following conditions: RX_Next ≤ first RLC SN ≤ RX_Next_Highest. The receiving end may discard data packet A if the first RLC SN satisfies RX_Next ≤ first RLC SN ≤ RX_Next_Highest; otherwise, no processing is performed. For example, referring to Figure 7B , assuming that RX_Next in the receive window is SN2 and RX_Next_Highest = SN7. If the first RLC SN is less than SN2 (e.g., SN0) or greater than SN7 (e.g., SN8), the discard condition is determined not to be met and no processing is performed. If the first RLC SN is greater than or equal to SN2 and less than or equal to SN7 (e.g., SN5), the receiving end may determine that the discard condition is met and discard packet A. In some embodiments, corresponding to the RLC layer of the receiving end, the discard condition may include that the first RLC SN corresponding to data packet A satisfies: RX_Next≤first RLC SN≤RX_Highest_status. The receiving end may discard data packet A if RX_Next≤first RLC SN≤RX_Highest_status; otherwise, no processing is performed. In some embodiments, corresponding to the RLC layer of the receiving end, the discard condition may include that the first RLC SN corresponding to the data packet A satisfies: RX_Next≤first RLC SN≤RX_Next_status_trigger. The receiving end may discard the data packet A if RX_Next≤first RLC SN≤RX_Next_status_trigger; otherwise, no processing is performed. In other embodiments, corresponding to the RLC layer at the receiving end, the discard condition may further include other conditions, such as the first RLC SN corresponding to packet A meeting the following conditions: RX_Next ≤ first RLC SN, or first RLC SN ≤ RX_Next_Highest, or first RLC SN ≤ RX_Highest_status, or first RLC SN ≤ RX_Next_status_trigger. When the first RLC SN is greater than RX_Highest_status, RX_NEXT_Highest may be updated, for example, to the largest SN among the discarded packets. In some embodiments, corresponding to the PDCP layer of the receiving end, the discard condition may include that the first COUNT value corresponding to the data packet A satisfies the following conditions: RX_DELIV ≤ first COUNT value ≤ RX_NEXT. The receiving end may discard the data packet A if RX_DELIV ≤ first COUNT value ≤ RX_NEXT; otherwise, no processing is performed. In other embodiments, corresponding to the PDCP layer at the receiving end, the discard condition may further include other conditions, such as the first COUNT value corresponding to packet A meeting the following conditions: RX_DELIV ≤ the first COUNT value, or the first COUNT value ≤ RX_NEXT. When the first COUNT value is greater than RX_NEXT, RX_NEXT may be updated, for example, to the largest SN among the discarded packets. After discarding data packet A (e.g., discarding data packet A when it meets the aforementioned discarding conditions, or directly discarding data packet A based on existing protocol logic), the device may also update the transmission status parameters. The following describes: Conditions for updating transmission status parameters In some embodiments, a device (e.g., a transmitter or receiver) updates a transmission status parameter according to an update condition. The update condition may be whether the discarded data packet is within the transmission window range, or further may be whether the SN number corresponding to the discarded data packet is within the transmission window range. In some embodiments, the transmission status parameters may include status parameters of the sending window (e.g., TX_Next_Ack, etc.), status parameters of the receiving window (e.g., RX_Next, RX_Highest_Status, RX_Next_Status_Trigger, etc.), status parameters of the PDCP layer (e.g., RX_DELIV and RX_REORD, etc.), etc. It should be understood that in other embodiments, the transmission status parameters may also be other parameters having the same or similar functions as the aforementioned TX_Next_Ack, RX_Next, RX_Highest_Status, RX_Next_Status_Trigger, RX_DELIV and RX_REORD, and these parameters may have different names from the aforementioned parameters. For example, using the RLC protocol layer as an example, at the transmitting end's RLC layer, the update condition may include that the first RLC SN corresponding to packet A (the discarded packet) satisfies the following conditions: TX_Next_Ack ≤ first RLC SN ≤ TX_Next. The transmitting end may update the state parameters of the transmit window (e.g., TX_Next_Ack) if the first RLC SN satisfies TX_Next_Ack ≤ first RLC SN ≤ TX_Next; otherwise, no processing is performed. The specific process for the transmitting end to update the state parameters of the transmit window is described below and is not detailed here. For example, referring to FIG. 7A , assuming the lower boundary of the transmit window is SN2, the upper boundary of the transmit window is SN2049, and TX_Next = SN7. If the first RLC SN is less than SN2 (e.g., SN0) or greater than SN7 (e.g., SN8), the discard condition is determined not to be met and no processing is performed. If the first RLC SN is greater than or equal to SN2 and less than or equal to SN7, or greater than SN7 (e.g., SN8), the transmitter may determine that the discard condition is met and update the state parameters of the transmit window. In other embodiments, corresponding to the RLC layer of the transmitting end, the update condition may further include other conditions, for example, the first RLC SN corresponding to the data packet A satisfies: TX_Next_Ack≤first RLC SN, or the first RLC SN≤TX_Next. For the RLC layer at the receiving end, the update condition may include that the second RLC SN corresponding to data packet B (a discarded data packet, such as a data packet discarded and / or to be discarded by the transmitting end, where data packet B may be an RLC SDU or RLC PDU) satisfies the following conditions: RX_Next ≤ second RLC SN ≤ RX_Next_Highest. The receiving end may update the status parameters of the receive window (e.g., RX_Next, RX_Highest_Status, RX_Next_Status_Trigger) if the first RLC SN satisfies RX_Next ≤ second RLC SN ≤ RX_Next_Highest; otherwise, no processing is performed. The specific process by which the receiving end updates the status parameters of the receive window will be described below and will not be elaborated upon here. For example, referring to FIG. 7B , assuming that RX_Next in the receive window is SN2 and RX_Next_Highest = SN7, if the second RLC SN is less than SN2 (e.g., SN0) or greater than SN7 (e.g., SN8), the second condition is determined not to be met and no processing is performed. If the second RLC SN is greater than or equal to SN2 and less than or equal to SN7 (e.g., SN5), the receiving end may determine that the second condition is met and update the state parameters of the receive window. In some embodiments, corresponding to the RLC layer of the receiving end, the update condition may include that the second RLC SN corresponding to data packet B satisfies the following conditions: RX_Next≤second RLC SN≤RX_Highest_status. The receiving end may update the status parameter of the receive window if RX_Next≤second RLC SN≤RX_Highest_status; otherwise, no processing is performed. In some embodiments, corresponding to the RLC layer of the receiving end, the update condition may include that the second RLC SN corresponding to the data packet B satisfies: RX_Next≤second RLC SN≤RX_Next_status_trigger. The receiving end may update the status parameters of the receiving window if RX_Next≤second RLC SN≤RX_Next_status_trigger; otherwise, no processing is performed. In other embodiments, corresponding to the RLC layer of the receiving end, the update condition may also include other conditions, for example, the first RLC SN corresponding to the data packet A satisfies: RX_Next≤first RLC SN, or first RLC SN≤RX_Next_Highest, or first RLC SN≤RX_Highest_status, or first RLC SN≤RX_Next_status_trigger. In some embodiments, for the PDCP layer at the receiving end, the update condition may include a first COUNT value corresponding to a packet C (a discarded packet, e.g., a packet discarded and / or to be discarded by the transmitting end, which may be a PDCP SDU or PDCP PDU) satisfying the following: RX_DELIV ≤ first COUNT value ≤ RX_NEXT. The receiving end may update the PDCP layer status parameters if RX_DELIV ≤ first COUNT value ≤ RX_NEXT; otherwise, no processing is performed. For example, at the PDCP layer of the receiving end, the update condition may include: the first COUNT value corresponding to the data packet C satisfies the following conditions: RX_DELIV ≤ first COUNT value ≤ RX_NEXT. The receiving end may update the PDCP layer status parameters if RX_DELIV ≤ first COUNT value ≤ RX_NEXT; otherwise, no action is taken. In other embodiments, corresponding to the PDCP layer of the receiving end, the update condition may further include other conditions, for example, the first COUNT value corresponding to the data packet A satisfies: RX_DELIV≤first COUNT value, or the first COUNT value≤RX_NEXT. In some embodiments, the receiving end may update the PDCP layer state parameters (e.g., RX_NEXT, RX_DELIV, and RX_REORD) when RX_DELIV is equal to the first COUNT value corresponding to the data packet C. The specific process of updating the PDCP layer state parameters at the receiving end will be described below and will not be repeated here. The device may update the transmission state parameters when determining that the data packet meets the update condition or when determining that the data packet is discarded. Here are some introductions: The state parameter update process of the sender In some embodiments, the transmitter updates the transmission status parameters of the transmitter based on the discarded data packets (data packets that the transmitter has discarded and / or is to be discarded), and further updates the status parameters of the transmitter based on the SN number of the discarded data packets. Exemplarily, corresponding to the transmitting end, the transmission status parameter includes a TX_Next_Ack parameter of the transmitting window. In some embodiments, the discarded data packets may include data packet A, or multiple consecutive data packets (consecutive data packets with sequence numbers (e.g., RLC SN, PDCP SN, etc.)) with data packet A as the first data packet. Accordingly, the relationship between the discarded data packets and the sending window may correspond to the following situations: Case 1: The discarded data packets may include multiple consecutive data packets with Data Packet A as the first data packet, and the RLC SN corresponding to Data Packet A is the same as the RLC SN corresponding to the lower boundary TX_Next_Ack of the transmission window. In this case, the RLC SNs corresponding to the multiple consecutive data packets with Data Packet A as the first data packet may be {TX_Next_Ack,..., SN_high}, where TX_Next_Ack < SN_high ≤ TX_Next. For example, referring to FIG. 8A, assume TX_Next_Ack = SN2, TX_Next = SN12, and the first RLC SN corresponding to Data Packet A is SN2. The multiple consecutive data packets with Data Packet A as the first data packet may be the data packets corresponding to SN2, SN3, and SN4. Case 2: The discarded data packets may include Data Packet A, and the RLC SN of Data Packet A is the same as the RLC SN corresponding to the lower boundary TX_Next_Ack of the transmission window. For example, referring to FIG. 8B, assume TX_Next_Ack = SN2, TX_Next = SN12, and the RLC SN of Data Packet A is SN2. Case 3: The discarded data packets may include multiple consecutive data packets with Data Packet A as the first data packet, and the RLC SN corresponding to Data Packet A is different from the RLC SN corresponding to the lower boundary TX_Next_Ack of the transmission window. In this case, the RLC SNs corresponding to the multiple consecutive data packets with Data Packet A as the first data packet may be {the first RLC SN,..., SN_high}, where TX_Next_Ack + 2 < SN_high ≤ TX_Next, and TX_Next_Ack + 1 < the first RLC SN ≤ TX_Next - 1. For example, referring to FIG. 8C, assume TX_Next_Ack = SN2, TX_Next = SN12, and the first RLC SN is SN6. Then the multiple consecutive data packets with Data Packet A as the first data packet may be the data packets corresponding to SN6, SN7, and SN8. Case 4: The discarded data packets may include Data Packet A, and the RLC SN of Data Packet A is different from the RLC SN corresponding to the lower boundary TX_Next_Ack of the transmission window. In this case, the RLC SN of Data Packet A may be any RLC SN greater than TX_Next_Ack and less than or equal to TX_Next. For example, referring to FIG. 8D, assume TX_Next_Ack = SN2, TX_Next = SN12, then the first RLC SN may be SN10. In some embodiments, the above Case 1 to Case 4 may exist simultaneously. For example, among the four cases shown in FIGS. 8A to 8D, multiple cases may exist simultaneously. Corresponding to situations 1 and 2, the sending end can directly update the lower boundary of the sending window to the RLC SN of the first unconfirmed received data packet after the data packet corresponding to the upper boundary of the RLC SN corresponding to the discarded data packet (the RLC SN with the largest value among the RLC SNs corresponding to the discarded data packet), or the next RLC SN of the upper boundary of the RLC SN corresponding to the discarded data packet. Exemplarily, the transmitter may update the lower boundary of the transmit window when the first RLC SN corresponding to data packet A is equal to the lower boundary (TX_Next_Ack) of the transmit window (or data packet A may be the data packet with the SN number corresponding to TX_Next_Ack. The transmitter may update the lower boundary of the transmit window when the RLC SN corresponding to one or more data packets among the discarded data packets is equal to the lower boundary (TX_Next_Ack) of the transmit window, or when the RLC SN corresponding to one or more data packets among the discarded data packets includes the lower boundary (TX_Next_Ack) of the transmit window. For example, the transmitter may update the lower boundary of the transmit window to: the fourth RLC SN following the third RLC SN corresponding to the last data packet among the consecutive discarded data packets with data packet A as the first data packet, or the fourth RLC SN following the third RLC SN corresponding to the last data packet among the consecutive discarded data packets with the SN number corresponding to TX_Next_Ack as the first data packet, or the fourth RLC SN following the third RLC SN corresponding to the last data packet among the consecutive discarded data packets including data packet A. The third RLC SN may be the RLC SN with the largest value among the RLC SNs corresponding to the consecutive discarded data packets with data packet A as the first data packet, or the third RLC SN may be the RLC SN with the largest value among the RLC SNs corresponding to the consecutive discarded data packets with the data packet corresponding to TX_Next_Ack as the first data packet, or the third RLC SN may be the RLC SN with the largest value among the RLC SNs corresponding to the consecutive discarded data packets including the data packet corresponding to TX_Next_Ack. For example, if the discarded data packets only include data packet A, the third RLC SN is the same as the first RLC SN; if the discarded data packets include multiple consecutive data packets with data packet A as the first data packet, the SNs corresponding to the multiple consecutive data packets with data packet A as the first data packet are {first RLC SN, ..., third RLC SN}, wherein the data packet corresponding to the fourth RLC SN is not discarded, that is, the data packet corresponding to the fourth RLC SN is not among the discarded data packets. In some embodiments, the fourth RLC SN may be the next RLC SN of the third RLC SN. In this case, if the transmitting end has received an acknowledgment feedback (ACK) for the data packet corresponding to the fourth RLC SN, the transmitting end may update the lower boundary of the sending window to the next RLC SN of the fourth RLC SN based on the existing protocol. It should be understood that an acknowledgment is a message sent by the receiving end to the transmitting end via a status report indicating that a data packet (e.g., an RLC SDU or RLC PDU) has been successfully received by the receiving end. Accordingly, if the status report indicates that the reception status of a data packet is NACK, this indicates that the data packet was not successfully received by the receiving end. The existing protocol updates the TX_Next_Ack message after receiving a status report to the minimum RLC SN corresponding to the data packet received in the status report (the feedback sent by the receiving end to the transmitting end regarding the received data packet, confirming reception or reception failure) that did not receive acknowledgment feedback. In some embodiments, the fourth RLC SN can be the smallest RLC SN among the RLC SNs corresponding to data packets that follow the data packet corresponding to the third RLC SN and for which no ACK has been received. Based on this approach, if the transmitting end has received ACKs corresponding to one or more consecutive data packets following the third RLC SN, the lower boundary of the transmit window can be directly updated to the fourth RLC SN, eliminating the need for the transmitting end to update the lower boundary according to existing protocols. This embodiment differs from the prior art in that the transmission status parameters need to be updated in conjunction with the information in the RLC SN joint status report corresponding to the discarded data packets. In some embodiments, the data packet corresponding to the fourth RLC SN is not discarded, or the data packet corresponding to the fourth RLC SN is not among the discarded data packets. That is, if the data packet corresponding to the smallest RLC SN among the RLC SNs corresponding to the data packets that follow the data packet corresponding to the third RLC SN and for which no ACK is received is among the discarded data packets, then the fourth RLC SN may be the RLC SN corresponding to the first data packet that is not among the discarded data packets and for which no ACK is received, after the consecutive data packets that include the smallest RLC SN among the discarded data packets (wherein the data packet corresponding to the smallest RLC SN may be the first data packet among the consecutive data packets or a data packet in the middle of the consecutive data packets). For example, assuming that the RLC SNs of the discarded packets are SN1, SN2, and SN3, as well as SN6, SN7, and SN8, and the transmitter has received packets with RLC SNs SN4 and SN5, but has not received packets with RLC SNs SN6, SN7, SN8, and SN9 (or may have received them), the smallest packet SN for which an ACK has not been received after the consecutively discarded packets SN1-SN3 is SN6, but SN6 is among the consecutively discarded packets SN6-SN8. Therefore, the transmitter can update the lower boundary of the send window to SN9. In one scenario, the transmitter can first update the lower boundary of the send window to SN4, and then update the lower boundary of the send window to SN9 after determining that the packets with RLC SNs SN4 and SN5 have been completely received by the receiver and that the packets corresponding to SN6, SN7, and SN8 are discarded packets. In another case, after TX_Next_Ack is updated to SN1, the transmitter can directly update the lower boundary of the sending window to SN9 if it determines that the RLC SNs of the discarded data packets are SN1, SN2, and SN3, as well as SN6, SN7, and SN8, and that the data packets with RLC SNs of SN4 and SN5 have been completely received by the receiver. In some embodiments, the third RLC SN is greater than or equal to TX_Next_Ack and less than or equal to TX_Next. In some embodiments, when the third RLC SN is greater than or equal to TX_Next_Ack, TX_Next_Ack has been updated to the next RLC SN of the second RLC SN. In some embodiments, the third RLC SN is greater than or equal to (the second RLC SN+1) and less than or equal to TX_Next. For example, corresponding to the situation shown in Figure 8A, TX_Next_Ack = SN2, TX_Next = SN12, and the RLC SN corresponding to the discarded data packet is SN2 (as the first RLC SN and the third RLC SN). If the transmitting end has not completely received the ACK for the data packet corresponding to SN3, the transmitting end can update the TX_Next_Ack to SN3 (as the fourth RLC SN). If the transmitting end has completely received the ACK for the data packet corresponding to SN3 and has not completely received the ACK for the data packet corresponding to SN4, the transmitting end can directly update the TX_Next_Ack to SN4, or first update the TX_Next_Ack to SN3 and then update it to SN4 (as the fourth RLC SN) based on the existing protocol. For another example, corresponding to the scenario shown in FIG8B , TX_Next_Ack = SN2, TX_Next = SN12, the RLC SNs corresponding to the discarded data packets are SN2-SN4, and the third RLC SN is SN4. If the transmitting end has not completely received the ACK for the data packet corresponding to SN5, the transmitting end may update the TX_Next_Ack to SN5 (as the fourth RLC SN). If the transmitting end has completely received the ACK for the data packet corresponding to SN5 but has not completely received the ACK for the data packet corresponding to SN6, the transmitting end may directly update the TX_Next_Ack to SN6 (as the fourth RLC SN), or first update the TX_Next_Ack to SN5 and then update it to SN6 based on the existing protocol. Corresponding to scenario 3 or scenario 4, the transmitter may wait until TX_Next_Ack is updated to be the same as the first RLC SN corresponding to packet A, and then update the lower boundary of the transmit window. For example, the transmitter may update the lower boundary of the transmit window to the fourth RLC SN following the third RLC SN corresponding to the last packet in the series of discarded packets starting with packet A. In some embodiments, waiting for the TX_Next_Ack to be updated to the same RLC SN as the first RLC SN corresponding to data packet A includes: after receiving the status report, updating the TX_Next_Ack to the RLC SN corresponding to the smallest data packet received in the status report for which no acknowledgment feedback has been received. When the updated TX_Next_Ack is the same as the first RLC SN, the transmitter may update the state parameters of the send window. For details, refer to the methods for updating the state parameters of the send window in the aforementioned scenarios 1 and 2, and are not further described here. In some embodiments, the fourth RLC SN may be the next RLC SN of the third RLC SN, or the smallest RLC SN among the RLC SNs corresponding to the data packet U that follows the data packet corresponding to the third RLC SN and for which no ACK is received. For another example, corresponding to the situation shown in Figure 8C, TX_Next_Ack = SN2, TX_Next = SN12, the RLC SNs corresponding to the discarded data packets are SN6-SN8, the first RLC SN is SN6 and the third RLC SN is SN8). The transmitter may update TX_Next_Ack to SN9 (as the fourth RLC SN) when TX_Next_Ack is updated to SN6 and the transmitter has not completely received the ACK for the data packet corresponding to SN9. The transmitter may also update TX_Next_Ack to SN10 (as the fourth RLC SN) when TX_Next_Ack is updated to SN6, the transmitter has completely received the ACK for the data packet corresponding to SN9, and has not completely received the ACK for the data packet corresponding to SN10. In some embodiments, if the transmitter updates TX_Next_Ack to an RLC SN after SN9 (for example, SN10) based on a status report, there is no need to update the status parameters of the sending window based on the discarded data packets. For example, corresponding to the situation shown in FIG8D , TX_Next_Ack = SN2, TX_Next = SN12, and the RLC SN corresponding to the discarded data packet is SN10 (as the first RLC SN and the third RLC CN). The transmitting end may update the TX_Next_Ack to SN11 when the TX_Next_Ack is updated to SN10 and the transmitting end has not completely received the ACK for the data packet corresponding to SN11. The transmitting end may update the TX_Next_Ack to SN12 when the TX_Next_Ack is updated to SN10 and the transmitting end has completely received the ACK for the data packet corresponding to SN11 but has not completely received the ACK for the data packet corresponding to SN12. In some embodiments, if the transmitting end updates the TX_Next_Ack to an RLC SN after SN10 (e.g., SN11) based on a status report, there is no need to update the state parameters of the sending window based on the discarded data packet. As shown in FIG. 8A to FIG. 8D , the data packets corresponding to the updated TX_Next_Ack are not discarded. If multiple situations among the situations shown in FIG. 8A to FIG. 8D occur, the transmitting end may also update the state parameters of the transmitting end based on the multiple situations. For example, assuming that the situations shown in Figures 8B and 8C exist at the same time, if the data packet corresponding to SN5 has not been completely received by the receiving end (for example, the sending end has not received the confirmation feedback of the data packet corresponding to SN5), the sending end can first update the lower boundary of the sending window to SN5, and then update the lower boundary of the sending window to SN9 after TX_Next_Ack is updated to SN6. For another example, assuming that the situations shown in FIG8B and FIG8C exist simultaneously, if the packet corresponding to SN5 has been completely received by the receiving end (for example, the transmitting end has received the confirmation feedback of the packet corresponding to SN5), the transmitting end can first update the lower boundary of the transmitting window to SN6. After TX_Next_Ack is updated to SN6, the transmitting end can update the lower boundary of the transmitting window to SN9 based on the consecutive discarded packets (packets corresponding to SN6-SN8). The transmitting end can also directly update the lower boundary of the transmitting window to SN9 when it is determined that the packet corresponding to SN5 has been completely received by the receiving end and the packet corresponding to SN6 is a discarded packet. In some embodiments, the transmitter can update the state parameters of the sending window by maintaining the transmitter discard window. The transmitter discard window may include a first discard state parameter (e.g., TX_Discard_Low) and a second discard state parameter (e.g., TX_Discard_High), wherein the first discard state parameter is used to indicate the lower boundary of the continuously discarded data packets U (e.g., the RLC SN with the smallest value among the RLC SNs corresponding to the continuously discarded data packets), and the second discard state parameter is used to indicate the upper boundary of the continuously discarded data packets (e.g., the RLC SN with the largest value among the RLC SNs corresponding to the continuously discarded data packets). Then, the transmitter can update the state parameters of the sending window based on the relationship between the lower boundary of the sending window and the first discard state parameter and the second discard state parameter. The maintenance process of the sender's discard window In some embodiments, the transmitter discard window is used to indicate the packet with the smallest RLC SN value corresponding to the discarded packet, or a plurality of consecutive discarded packets with the smallest RLC SN value corresponding to the discarded packet. For example, assuming that the RLC SNs corresponding to the discarded packets are SN2, SN5, SN8, and SN9, then TX_Discard_High = TX_discard_low = SN2. For another example, assuming that the RLC SNs corresponding to the discarded packets are SN2, SN3, SN4, SN8, and SN9, then TX_Discard_High = SN4 and TX_discard_low = SN2. In some embodiments, if the transmitting end has determined that there is TX_Discard_High, TX_discard_low, and the RLC SN (one RLC SN or multiple consecutive RLC SNs) corresponding to the data packet requested to be discarded by the PDCP layer and has been discarded are both smaller than the current TX_discard_low, the transmitting end may update TX_Discard_High to the upper boundary of the RLC SN corresponding to the data packet requested to be discarded by the PDCP layer, and update TX_discard_low to the lower boundary of the RLC SN corresponding to the data packet requested to be discarded. In some embodiments, if the transmitting end has determined that TX_Discard_High, TX_discard_low, and the RLC SNs (one RLC SN or multiple consecutive RLC SNs) corresponding to the data packets requested to be discarded by the PDCP layer are both greater than the current TX_discard_high, the transmitting end may not update TX_Discard_High and TX_discard_low. In some embodiments, if the transmitting end has determined that there is TX_Discard_High, TX_discard_low, and the RLC SN corresponding to the data packet requested to be discarded by the PDCP layer overlaps with [TX_discard_low, TX_Discard_High] and can be superimposed into a continuous RLC SN interval, the transmitting end can update TX_Discard_High to the upper boundary of the continuous RLC SN interval (the maximum value of the continuous RLC SN interval) and update TX_discard_low to the lower boundary of the continuous RLC SN interval (the minimum value in the continuous RLC SN interval). Exemplarily, FIG9A to FIG9E show schematic diagrams of a sender updating a sender discard window according to some embodiments of the present application. Assume that the transmitter has determined TX_Discard_High and TX_discard_low (hereinafter, the transmitter discard window corresponding to the determined TX_Discard_High and TX_discard_low is referred to as the current transmitter discard window), and the upper boundary of the RLC SN of the data packet requested to be discarded by the PDCP layer is SN_high, and the lower boundary is SN_low ≤ SN_high. The transmitter can update the state parameters of the transmitter discard window based on the relationship between SN_high, SN_low, and the current transmitter discard window. Referring to Figure 9A, if SN_high is less than TX_discard_low, it means that all RLC SNs corresponding to the data packets requested to be discarded are less than TX_discard_low, and the data packets requested to be discarded do not overlap with the current discard window. The sender can update TX_discard_low to SN_low and TX_discard_high to SN_high. 9B , if SN_low is greater than TX_discard_high, it means that all RLC SNs corresponding to the packets requested to be discarded are greater than TX_discard_high, and the transmitter does not need to update the transmitter discard window. 9C , if SN_high is greater than or equal to TX_discard_high and SN_low is less than or equal to TX_discard_low, it indicates that the data packet requested to be discarded includes the current transmitter discard window, and the transmitter may update TX_discard_low to SN_low and TX_discard_high to SN_high. 9D , if SN_high is greater than or equal to TX_discard_low and less than or equal to TX_discard_high, and SN_low is less than TX_discard_low, it indicates that the data packet requested to be discarded and the current transmitter discard window constitute a new continuous data packet, and the transmitter can update TX_discard_low to SN_low. 9E , if SN_low is greater than TX_discard_low and less than or equal to TX_discard_high, and SN_high is greater than TX_discard_high, it indicates that the data packet requested to be discarded and the current transmitter discard window constitute a new continuous data packet, and the transmitter can update TX_discard_high to SN_high. In some embodiments, if the updated TX_discard_high is greater than Tx_Next, the transmitter may update TX_discard_high to Tx_Next. Alternatively, when TX_discard_high needs to be updated to SN_high, if SN_high is greater than Tx_Next, the transmitter may update TX_discard_high to Tx_Next. The process by which the sender updates the state parameters of the send window based on the state parameters of the sender's discard window When the transmitter determines that the lower boundary of the send window (Tx_Next_Ack) is the same as the lower boundary of the send window (TX_discard_low), the lower boundary of the send window can be updated to the RLC SN after the upper boundary of the send window (TX_discard_high), or the RLC SN of the first data packet received ACK after the upper boundary of the send window (TX_discard_high). In some embodiments, after updating the lower boundary of the transmit window (TX_Next_Ack), if there are still discarded packets within the transmit window, the transmitter may update or maintain TX_discard_low and TX_discard_high based on the discarded packets within the transmit window. The specific update method can refer to the above-mentioned content of maintaining the transmit end discard window, which is not repeated here. In some embodiments, if the updated lower boundary of the sending window is greater than Tx_Next, the transmitting end may update the lower boundary of the sending window to Tx_Next. In some embodiments, after the status parameters of the sending window have been updated based on the current sending end discard window (for example, the lower boundary of the sending window has been updated to the RLC SN after the upper boundary of the sending end discard window (TX_discard_high), or the RLC SN of the first data packet after the upper boundary of the sending end discard window (TX_discard_high) that has not received an ACK), if there are still discarded data packets, the sending end can update or establish the sending end discard window based on the embodiments shown in Figures 9A to 9E, and update the status parameters of the sending window based on the updated or established sending end discard window. In some embodiments, the transmitting end may update the state parameters of the transmitting window based on an existing protocol (e.g., TS28.322 protocol) instead of the RLC SN corresponding to the discarded data packet. Specifically, in this embodiment, after or during discarding the data packet to be discarded, the transmitting end may send discard information indicating the discarded data packet (the data packet discarded and / or to be discarded by the transmitting end) to the receiving end. After receiving the discard information, the receiving end may send a status report to the transmitting end, and the status report includes the reception status (e.g., ACK) of the data packet corresponding to the data packet discarded or to be discarded by the transmitting end. After receiving the status report, the transmitting end may update the lower boundary Tx_Next_Ack of the transmitting window to the RLC SN with the smallest value among the RLC SNs corresponding to the data packets for which ACK has not yet been received. In this way, there is no need to modify the process of updating the transmitting window by the transmitting end. Here are some introductions: The process of updating the state parameters at the receiving end In some embodiments, the receiving end may update the status parameters of the receiving end based on the data packets that have been discarded and / or are to be discarded by the sending end, further update the status parameters of the sending end based on the SN number of the data packets that have been discarded or are to be discarded by the sending end, or further update the status parameters of the sending end based on the COUNT value of the data packets that have been discarded and / or are to be discarded. In some embodiments, the receiving end may update the status parameters of the RLC layer, such as RX_Next, RX_Highest_Status, RX_Next_Status_Trigger, etc. The receiving end may also update the status parameters of the PDCP layer, such as RX_DELIV and RX_REORD, etc. The process by which the receiving end updates the state parameters of the RLC layer Exemplarily, using the RLC layer as an example, when the second RLC SN corresponding to data packet B is equal to the lower boundary of the receive window (RX_Next), (or, data packet B may be the data packet with the SN number corresponding to RX_Next. If the RLC SN corresponding to one or more of the discarded data packets is equal to the lower boundary of the receive window (RX_Next), or if the RLC SN corresponding to one or more of the discarded data packets includes the lower boundary of the receive window (RX_Next)), the receiving end may update the lower boundary of the receive window. Data packet B is a data packet determined by the receiving end to have been discarded or to be discarded by the transmitting end (i.e., the aforementioned discarded data packet), and may be indicated by the transmitting end to the receiving end. Exemplarily, the receiving end may update the lower boundary of the receive window to: the sixth RLC SN following the fifth RLC SN corresponding to the last packet of the consecutive discarded data packets starting with packet B (in some embodiments, the packet corresponding to the sixth RLC SN is not discarded), or the RLC SN following the RLC SN corresponding to the last packet of the consecutive discarded data packets including the SN number corresponding to RX_Next (in some embodiments, the packet corresponding to the RLC SN is not discarded). The fifth RLC SN may be the RLC SN with the largest numerical value among the RLC SNs corresponding to the consecutive discarded data packets starting with packet B, or the fifth RLC SN may be the RLC SN with the largest numerical value among the RLC SNs corresponding to the consecutive discarded data packets including packet B. For example, if the discarded data packets only include packet B, the fifth RLC SN is the same as the second RLC SN; if the discarded data packets include multiple consecutive data packets starting with packet B, the SNs corresponding to the multiple consecutive data packets starting with packet B are {second RLC SN, ..., fifth RLC SN}. In some embodiments, the data packet corresponding to the sixth RLC SN is not discarded, or in other words, the data packet corresponding to the sixth RLC SN is not among the discarded data packets. That is, if the data packet corresponding to the smallest RLC SN among the RLC SNs corresponding to the data packets that are not completely received after the data packet corresponding to the fifth RLC SN is a data packet among the discarded data packets, then the sixth RLC SN may be the RLC SN corresponding to the first data packet that is not among the discarded data packets and is not completely received, after the consecutive data packets including the smallest RLC SN among the discarded data packets (wherein the data packet corresponding to the smallest RLC SN may be the first data packet among the consecutive data packets or a data packet in the middle of the consecutive data packets). For example, assuming that the RLC SNs of the discarded packets are SN1, SN2, and SN3, as well as SN6, SN7, and SN8, and the receiving end has received packets with RLC SNs SN4 and SN5 but has not completely received packets with RLC SNs SN6, SN7, SN8, and SN9 (which may have been completely received), the receiving end may update the lower boundary of the receive window to SN9. In one scenario, the receiving end may first update the lower boundary of the receive window to SN4, and then, upon determining that the packets with RLC SNs SN4 and SN5 have been completely received and the packets corresponding to SN6, SN7, and SN8 are discarded packets, update the lower boundary of the receive window to SN9. In another scenario, after updating the lower boundary of the receive window to SN1, the receiving end may directly update the lower boundary of the receive window to SN9 upon determining that the RLC SNs of the discarded packets are SN1, SN2, and SN3, as well as SN6, SN7, and SN8, and the packets with RLC SNs SN4 and SN5 have been completely received. In some embodiments, the sixth RLC SN may be the next RLC SN of the fifth RLC SN. In one case, if the receiving end has completely received the data packet corresponding to the sixth RLC SN, or the receiving end has sent an acknowledgment feedback (ACK) of the data packet corresponding to the sixth RLC SN to the sending end, the receiving end can update the lower boundary of the receiving window to the next RLC SN of the sixth RLC SN or the RLC SN after the sixth RLC SN based on the existing protocol. In one case, if the receiving end has completely received the data packet corresponding to the sixth RLC SN and the data packets following the sixth RLC SN, the receiving end may update the lower boundary of the receive window to the SN number of the first incompletely received data packet following the sixth RLC SN based on the existing protocol. The existing protocol includes updating RX_Next to the RLC SN number corresponding to the first incompletely received data packet following RX_Next when a data packet is completely received (i.e., all bytes of the data packet have been received) and the RLC SN number of the data packet is equal to RX_Next. In this embodiment, RX_Next is first updated to the RLC SN next to the fifth RLC SN and, optionally, is then updated according to the existing protocol. In some embodiments, the sixth RLC SN may be the RLC SN corresponding to the first incompletely received data packet after the fifth RLC SN, and the data packet corresponding to the sixth RLC SN is not discarded. Based on this approach, when the receiving end determines that the data packets corresponding to one or more consecutive RLC SNs after the fifth RLC SN are completely received, or when the receiving end has sent ACKs for the data packets corresponding to one or more consecutive RLC SNs after the fifth RLC SN to the transmitting end, the lower boundary of the receiving window can be directly updated to the sixth RLC SN, so that the receiving end does not need to update again according to the existing protocol. In some embodiments, the sixth RLC SN is greater than or equal to RX_Next and less than or equal to RX_Next_Highest. In some embodiments, the sixth RLC SN is greater than or equal to the fifth RLC SN and less than or equal to RX_Next_Highest. In some embodiments, referring to FIG10A , if the updated RX_Next is greater than RX_Highest_Status, the receiving end may further update RX_Highest_Status to the updated RX_Next. For example, if the receiving end updates RX_Next to the sixth RLC SN, and the sixth RLC SN is greater than RX_Highest_Status, the receiving end may further update RX_Highest_Status to the sixth RLC SN. In some embodiments, referring to FIG10B , if the updated RX_Next is greater than or equal to RX_Next_Status_trigger, the reassembly timer is stopped. As shown in FIG4 , where RX_Next is less than RX_Next_Highest, the receiving end may further update RX_Next_Status_trigger to the RLC SN corresponding to RX_Next_Highest and start (e.g., if the reassembly timer is not running or stopped) or restart (e.g., if the reassembly timer is running) the reassembly timer. For example, if the receiving end updates RX_Next to the sixth RLC SN, and the sixth RLC SN is greater than RX_Next_Status_Trigger, the receiving end may further update RX_Next_Status_Trigger to the RLC SN corresponding to RX_Next_Highest and start or restart the reassembly timer. In some embodiments, when the fifth RLC SN is greater than or equal to RX_Highest_Status (or when the RLC SN corresponding to one or more data packets among the discarded data packets is greater than or equal to RX_Highest_Status), the receiving end may update RX_Highest_Status to the sixth RLC SN corresponding to the data packet following the fifth RLC SN. As in the aforementioned embodiment, the sixth RLC SN may be the RLC SN next to the fifth RLC SN, or the sixth RLC SN may be the RLC SN corresponding to the first incompletely received data packet after the fifth RLC SN. For example, if the first N data packets among the discarded data packets are consecutive data packets, and the RLC SN corresponding to the last data packet among the first N data packets is greater than or equal to RX_Highest_Status, the receiving end may update RX_Highest_Status to the RLC SN corresponding to the data packet following the last data packet among the first N data packets (for example, the RLC SN corresponding to the next data packet after the last data packet among the first N data packets, or the RLC SN with the smallest value among the RLC SNs corresponding to the incompletely received data packets following the last data packet among the first N data packets). In some embodiments, when the fifth RLC SN is greater than or equal to RX_Next_Status_Trigger (or when one or more of the discarded data packets have RLC SNs greater than or equal to RX_Next_Status_Trigger), and / or when the second RLC SN is less than or equal to RX_Highest_Status (or when one or more of the discarded data packets have RLC SNs greater than or equal to RX_Next_Status_Trigger), the receiving end may update RX_Next_Status_Trigger to the RLC SN corresponding to RX_Next_Highest and start or restart the reassembly timer. For example, if the first N discarded data packets are consecutive data packets, and the RLC SN corresponding to the last of the first N data packets is greater than or equal to RX_Next_Status_Trigger, the receiving end may update RX_Next_Status_Trigger to the RLC SN corresponding to RX_Next_Highest and start or restart the reassembly timer. In some embodiments, when the RLC SN corresponding to any of the discarded data packets is different from RX_Next, the receiving end does not update RX_Next. In some embodiments, when the receiving end receives a complete data packet and the RLC SN of the data packet is RX_Next, the receiving end may update RX_Next to the smallest SN among the RLC SNs corresponding to the incompletely received data packets. In some embodiments, when RX_Next is updated to the RLC SN with the smallest value among the RLC SNs corresponding to the discarded data packets, the receiving end may update RX_Next to the RLC SN of the data following the consecutive data packets among the discarded data packets where the RLC SN with the smallest value is located. In some embodiments, the receiving end may update the state parameters of the receiving window by maintaining the receiving end discard window. The state parameters of the receiving end discard window may include a third discard state parameter (e.g., RX_Discard_Low) and a fourth discard state parameter (e.g., RX_Discard_High). The third discard state parameter is used to indicate the lower boundary of consecutive discarded data packets (which may include consecutive data packets with the data packet with the smallest RLC SN in the portion of data packets as the first data packet among the data packets discarded and / or to be discarded by the transmitting end) (e.g., the RLC SN with the smallest value among the RLC SNs corresponding to the consecutive discarded data packets), and the fourth discard state parameter is used to indicate the upper boundary of consecutive discarded data packets (e.g., the RLC SN with the largest value among the RLC SNs corresponding to the consecutive discarded data packets. Furthermore, the third discard state parameter may correspond to the RLC SN of the last data packet among the consecutive discarded data packets with the data packet corresponding to the first data packet). The receiving end may then update the state parameters of the PCDP layer based on the relationship between the receiving window state parameter, the third discard state parameter, the fourth discard state parameter, and RX_DELIV. The maintenance process of the receiver's discard window In some embodiments, the receiving end discard window is used to indicate the SN of the data packet with the smallest RLC SN value corresponding to the discarded data packet, or the SN of multiple consecutively discarded data packets in which the data packet with the smallest RLC SN value corresponding to the discarded data packet is located. Multiple consecutively discarded data packets refer to the RLC SN numbers of the multiple data packets being consecutive. For example, assuming that the RLC SNs corresponding to the discarded data packets are SN2, SN5, SN8, and SN9, then RX_Discard_High = RX_discard_low = SN2. For another example, assuming that the RLC SNs corresponding to the discarded data packets are SN2, SN3, SN4, SN8, and SN9, then RX_Discard_High = SN4 and RX_discard_low = SN2. In some embodiments, if the receiving end has determined that there is RX_Discard_High and RX_discard_low, and the receiving end determines that the RLC SN corresponding to the data packet discarded by the sending end (one RLC SN or multiple consecutive RLC SNs) is less than the current RX_discard_low, the receiving end can update RX_Discard_High to the upper boundary of the RLC SN corresponding to the data packet requested to be discarded, and update RX_discard_low to the lower boundary of the RLC SN corresponding to the data packet requested to be discarded. In some embodiments, if the receiving end has already determined that there is RX_Discard_High and RX_discard_low, and the receiving end determines that the RLC SNs (one RLC SN or multiple consecutive RLC SNs) corresponding to the data packets discarded by the sending end are all greater than the current RX_discard_high, the receiving end may not update RX_Discard_High and RX_discard_low. In some embodiments, if the receiving end has determined that there is RX_Discard_High and RX_discard_low, and the receiving end determines that the RLC SN corresponding to the data packet discarded by the sending end overlaps with [RX_discard_low, RX_Discard_High] and can be superimposed into a continuous RLC SN interval, the receiving end can update RX_Discard_High to the upper boundary of the continuous RLC SN interval (the maximum value of the continuous RLC SN interval) and update RX_discard_low to the lower boundary of the continuous RLC SN interval (the minimum value in the continuous RLC SN interval). Exemplarily, FIG. 11A to FIG. 11E are schematic diagrams showing a receiving end updating a receiving end discarding window according to some embodiments of the present application. Assume that the receiving end has determined RX_Discard_High and RX_discard_low (hereinafter, the receiving end discard window corresponding to the determined RX_Discard_High and TX_discard_low is referred to as the current receiving end discard window). The receiving end determines that the upper boundary of the RLC SN of the data packet discarded by the transmitting end is SN_high, and the lower boundary is SN_low ≤ SN_high. The transmitting end can update the state parameters of the receiving end discard window based on the relationship between SN_high, SN_low, and the current receiving end discard window. Referring to Figure 11A, if SN_high is less than RX_discard_low, it means that all RLC SNs corresponding to the data packets requested to be discarded are less than RX_discard_low, and the data packets requested to be discarded do not overlap with the current discard window. The receiving end can update RX_discard_low to SN_low and RX_discard_high to SN_high. 11B , if SN_low is greater than RX_discard_high, it means that all RLC SNs corresponding to the data packets requested to be discarded are greater than RX_discard_high, and the receiving end does not need to update the receiving end discard window. 11C , if SN_high is greater than or equal to RX_discard_high and SN_low is less than or equal to RX_discard_low, it indicates that the data packet requested to be discarded includes the current receiving end discard window, and the receiving end may update RX_discard_low to SN_low and RX_discard_high to SN_high. 11D , if SN_high is greater than or equal to RX_discard_low and less than or equal to RX_discard_high, and SN_low is less than RX_discard_low, it indicates that the data packet requested to be discarded and the current receiving end discard window constitute a new continuous data packet, and the receiving end may update RX_discard_low to SN_low. 11E , if SN_low is greater than RX_discard_low and less than or equal to RX_discard_high, and SN_high is greater than RX_discard_high, it indicates that the data packet requested to be discarded and the current receiving end discard window constitute a new continuous data packet, and the receiving end can update RX_discard_high to SN_high. In some embodiments, referring to FIG11F , the receiving end discard window includes RX_Highest_Status and, optionally, does not include RX_Next_Status_Trigger (equivalent to RX_discard_low ≤ RX_Highest_Status ≤ RX_discard_high). The receiving end may update RX_Highest_Status to the RLC SN corresponding to the first data packet that has not been completely received and has an RLC SN greater than RX_discard_high. For example, if the data packet corresponding to RX_discard_high+1 has not been completely received, the receiving end may update RX_Highest_Status to RX_discard_high+1. If the data packet corresponding to RX_discard_high+1 has been completely received, but the data packet corresponding to RX_discard_high+2 has not been completely received, the receiving end may update RX_Highest_Status to RX_discard_high+2, and so on. It should be understood that in other embodiments, the receiving end may also update RX_Highest_Status when updating the status parameter of the receiving window based on the continuously discarded data packets indicated by the receiving end discard window. The embodiment of the present application does not limit the timing of updating RX_Highest_Status. In some embodiments, referring to FIG11G , if the updated receiving end discard window includes RX_Highest_Status and RX_Next_Status_Trigger (equivalent to RX_discard_low≤RX_Highest_Status≤RX_Next_Status_Trigger≤RX_discard_high), the receiving end may update RX_Highest_Status to the RLC SN corresponding to the first data packet that is not completely received and is greater than RX_discard_high, and update RX_Next_Status_Trigger to RX_Next_highest, and start or restart the timer. For example, if the data packet corresponding to RX_discard_high+1 is not completely received, the receiving end may update RX_Highest_Status to RX_discard_high+1 and update RX_Next_Status_Trigger to RX_Next_highest. If the data packet corresponding to RX_discard_high+1 has been completely received, and the data packet corresponding to RX_discard_high+2 has not been completely received, the receiving end can update RX_Highest_Status to RX_discard_high+2 and update RX_Next_Status_Trigger to RX_Next_highest, and so on. It should be understood that in other embodiments, the receiving end may also update RX_Highest_Status and RX_Next_Status_trigger when updating the status parameters of the receiving window based on the receiving end discard window. The embodiment of the present application does not limit the timing of updating RX_Highest_Status and RX_Next_Status_trigger. Here are some introductions: The process by which the receiving end updates the state parameters of the receiving window based on the state parameters of the receiving end discarded window When the receiving end determines that the lower boundary of the receiving window (RX_Next) is the same as the lower boundary of the receiving end discard window (RX_discard_low), the lower boundary of the receiving window can be updated to the RLC SN after the upper boundary of the receiving end discard window (RX_discard_high), or the RLC SN of the first incompletely received data packet after the data packet corresponding to the upper boundary of the receiving end discard window (RX_discard_high). In some embodiments, corresponding to the RLC layer, the data packet may be an RLC PDU and / or an RLC SDU. In some embodiments, after updating the lower boundary of the receive window (RX_Next), if there are still discarded packets within the receive window, the receiving end may update or maintain RX_discard_low and RX_discard_high based on the discarded packets within the receive window. The specific update method can refer to the above content of maintaining the discard window of the receiving end, which is not repeated here. In some embodiments, if RX_discard_low≤RX_Highest_Status≤RX_discard_high, the receiving end may update RX_Highest_Status to the RLC SN corresponding to the first data packet that has not been completely received and has an RLC SN greater than RX_discard_high. In some embodiments, if RX_discard_low≤RX_Next_Status_Trigger≤RX_discard_high), the receiving end may update RX_Next_Status_Trigger to RX_Next_highest and start or restart the timer. In some embodiments, after the lower boundary of the receiving window has been updated to the RLC SN after the upper boundary of the receiving end discard window (RX_discard_high), or the RLC SN of the first incompletely received data packet after the upper boundary of the receiving end discard window (RX_discard_high), if there are still discarded data packets, the receiving end can update or establish the receiving end discard window based on the embodiments shown in Figures 11A to 11G, and update the status parameters of the sending window based on the updated or established receiving end discard window. It can be seen from the above embodiments that the lower boundary of the receiving window will not be updated to the SN number corresponding to the discarded data packet. In some embodiments, after updating the state parameters of the receive window, the receiving end may also send a status report to the transmitting end, indicating that all data packets corresponding to the discarded data packet have been received. For example, the status report may include ACKs for all data packets corresponding to the discarded data packet. In some embodiments, the received status of the data packet corresponding to the discarded data packet in the status report is ACK, where ACK indicates that the data packet has been completely received. In this way, the transmitting end can update the state parameters of the sending window based on existing protocols (such as TS28.322 protocol), for example, updating the lower boundary Tx_Next_Ack of the sending window to the RLC SN with the smallest value among the RLC SNs corresponding to the data packets for which ACK has not yet been received. The process of the receiver sending a status report to the sender In some embodiments, the receiving end may trigger the sending of a status report to the transmitting end based on the relationship between the RLC SN corresponding to the discarded data packet and RX_Highest_Status and RX_Next_Status_Trigger. In some embodiments, the RCL SN corresponding to the discarded data packet may correspond to the following situations 5 to 7, taking the relationship between the discard window and RX_Highest_Status and RX_Next_Status_Trigger as an example. Case 5: RX_discard_low≤RX_Highest_Status≤RX_discard_high <RX_Next_Status_Trigger 12A , this situation may be a situation where the receiving end updates RX_Highest_Status in the process of maintaining a discard window (e.g., the situation shown in FIG11F ), or a situation where RX_Highest_Status is updated in the process of updating the status parameters of the receiving window based on the receiving end discard window. Case 6: RX_discard_low≤RX_Highest_Status≤RX_Next_Status_Trigger≤RX_discard_high Referring to Figure 12B, this situation may be a situation where the receiving end has updated RX_Highest_Status and RX_Next_Status_Trigger in the process of maintaining the receiving end discard window (for example, the situation shown in Figure 11G), or a situation where RX_Highest_Status and RX_Next_Status_Trigger have been updated in the process of updating the status parameters of the receiving window based on the receiving end discard window. Case 7: RX_discard_low ≤ RX_discard_high <RX_Highest_Status 12C , the situation may be that all RLC SNs corresponding to the receiving end discard window are smaller than RX_Highest_Status, and the receiving end does not update RX_Highest_Status and RX_Next_Status_Trigger in the process of maintaining the receiving end discard window and updating the status parameters of the receiving window based on the receiving end discard window. In some embodiments, corresponding to scenarios 5 and 6, the receiving end may trigger a status report to be sent to the transmitting end due to updating RX_Highest_Status (or RX_Highest_Status and RX_Next_Status_Trigger) by maintaining the receiving end discard window and updating the receiving window status parameters based on the receiving end discard window. In some embodiments, corresponding to scenario 7, the receiving end can determine whether ACKs for all data packets indicated by the receiving end's discard window have been sent to the sending end. If the receiving end has already sent ACKs for all data packets indicated by the receiving end's discard window to the sending end, it means that the sending end will no longer transmit or retransmit the data packets indicated by the receiving end's discard window, and there is no need to trigger a status report. If the ACK for at least one data packet among the data packets indicated by the receiving end's discard window has not yet been sent to the sending end (for example, the receiving status corresponding to the at least one data packet has not been sent, or the NACK receiving status for the at least one data packet has been sent), it means that the sending end will continue to transmit or retransmit the at least one data packet, and it is necessary to trigger the sending of a status report to the sending end. In this way, if the receiving end has already sent ACKs for all data packets indicated by the receiving end's discard window to the sending end, there is no need to trigger a status report based on the current receiving end's discard window, which can reduce the frequency and content of status reports sent by the receiving end. In some embodiments, corresponding to any of Scenarios 5-7, when a transmission opportunity exists, the receiving end can directly send a status report to the sending end based on the existing transmission opportunity, without having to wait for the t-StatusProhibit to time out before sending the status report. In this way, the receiving end can promptly send an ACK to the sending end indicating the data packets corresponding to the receiving end's discard window, allowing the sending end to promptly stop transmitting or retransmit the data packets corresponding to the receiving end's discard window, thereby improving communication efficiency between the sending end and the receiving end. In some embodiments, regardless of whether the receiving end receives the data packet corresponding to the receiving end's discard window, the receiving status of the data packet corresponding to the receiving end's discard window in the status report sent by the receiving end to the sending end is ACK, that is, even if the data packet corresponding to the receiving end's discard window is not received, the receiving status of the corresponding data packet will be set to ACK, and the receiving status of the data packet will not be set to NACK. The process by which the receiving end updates the state parameters of the PDCP layer In some embodiments, the receiving end can update the status parameters of the PDCP layer of the receiving end based on the discarded data packets (data packets discarded and / or to be discarded by the sending end), and further update the status parameters of the PDCP layer of the receiving end based on the SN number of the discarded data packets. Exemplarily, for the PDCP layer at the receiving end, the state parameters may include RX_DELIV, RX_REORD, etc. In some embodiments, corresponding to the PDCP layer, the data packet may be a PDCP PDU and / or a PDCP SDU. In some embodiments, the discarded data packets may include data packet C, or multiple consecutively discarded data packets (count value continuous data packets) with data packet C as the first data packet, wherein data packet C is the data packet with the smallest count value among the discarded data packets. In the case where the COUNT value corresponding to data packet C is equal to RX_DELIV (optionally, data packet C can be a data packet with a COUNT value corresponding to RX_DELIV. In the case where the COUNT value corresponding to one or more data packets among the discarded data packets is equal to RX_DELIV, or in the case where the COUNT value corresponding to one or more data packets among the discarded data packets includes RX_DELIV), the receiving end can update RX_DELIV to the third COUNT value after the second COUNT value corresponding to the last data packet among the consecutive discarded data packets with data packet C as the first data packet. For example, if the discarded data packets only include data packet C, the second COUNT value is the same as the first COUNT value; if the discarded data packets include multiple consecutive data packets with data packet C as the first data packet, the COUNT values corresponding to the packets are {first COUNT value, ..., second COUNT value}. In some embodiments, the third COUNT value may be the next COUNT value of the second COUNT value. In some embodiments, the third COUNT value may be a COUNT value corresponding to packets whose COUNT value is subsequent to the second COUNT value and which are not delivered to the upper layer by the first PDCP layer. For example, if the COUNT values corresponding to the consecutive packets corresponding to the discarded packet are C2, C3, and C4 (C2, C3, and C4 are consecutive COUNT values) and the packet corresponding to COUNT value C5 is not delivered to the upper layer, the receiving end may update RX_DELIV to C5. For another example, if the COUNT values corresponding to the consecutive packets corresponding to the discarded packet are C2, C3, and C4 and the packets corresponding to COUNT values C5 and C6 are delivered to the upper layer, and the packet corresponding to COUNT value C7 is not delivered to the upper layer, the receiving end may update RX_DELIV to C7. In some embodiments, the data packet corresponding to the third COUNT value is not discarded, that is, the data packet corresponding to the third COUNT value is not among the discarded data packets. That is, if the data packet corresponding to the smallest COUNT value among the COUNT values corresponding to the data packets that are not delivered to the upper layer after the data packet corresponding to the second COUNT value is a data packet among the discarded data packets, then the third COUNT value can be the COUNT value corresponding to the first data packet (e.g., the data packet with the smallest COUNT value) that is not among the discarded data packets and not delivered to the upper layer after the consecutive data packets including the smallest COUNT value among the discarded data packets (wherein, the data packet corresponding to the smallest COUNT value can be the first data packet of the consecutive data packets or a data packet in the middle of the consecutive data packets) For example, assuming the COUNT values of discarded packets are C1, C2, and C3, as well as C6, C7, and C8, and packets with COUNT values of C4 and C5 have been submitted to the upper layer, while packets with COUNT values of C6, C7, C8, and C9 have not been submitted to the upper layer (or may have been submitted to the upper layer), the receiving end may update RX_DELIV to C9. In one scenario, the receiving end may first update RX_DELIV to C4, and then update RX_DELIV to C9 if it determines that packets with COUNT values of C4 and C5 have been submitted to the upper layer and packets corresponding to C6, C7, and C8 are discarded packets. In another scenario, after updating RX_DELIV to C1, the receiving end may directly update RX_DELIV to C9 if it determines that packets with COUNT values of C4 and C5 have been submitted to the upper layer and packets corresponding to C6, C7, and C8 are discarded packets. In some embodiments, if the COUNT value corresponding to the last data packet of the consecutive discarded data packets is greater than or equal to RX_REORD (for example, there are one or more data packets among the discarded data packets whose corresponding COUNT values are greater than or equal to RX_REORD), the receiving end can update RX_REORD to RX_NEXT and start the reordering timer. In some embodiments, if the COUNT value corresponding to the consecutively discarded data packets is greater than or equal to RX_REORD, the receiving end may update RX_REORD to RX_NEXT and start a reordering timer. In some embodiments, referring to FIG13A , if the updated RX_DELIV is less than or equal to RX_REORD, the receiving end may not update RX_REORD. It should be understood that in some embodiments, the updated RX_DELIV is less than RX_NEXT. In some embodiments, referring to FIG13B , if the updated RX_DELIV is greater than RX_REORD, the reordering timer is stopped, wherein the updated RX_DELIV is less than RX_NEXT, the receiving end may further update RX_REORD to RX_NEXT, RX_DELIV is less than the updated RX_REORD (i.e., RX_NEXT), and start the reordering timer. For example, if the updated RX_DELIV is greater than RX_REORD, the receiving end may start the reordering timer when the reordering timer is not running or stops running. In some embodiments, the receiving end may maintain a PDCP discard window at the PDCP layer to update the state parameters of the PDCP layer. The discard state parameters of the PDCP discard window may include a fifth discard state parameter (e.g., PDCPRX_Discard_Low) and a sixth discard state parameter (e.g., PDCPRX_Discard_High). The fifth discard state parameter is used to indicate the lower boundary of the COUNT value corresponding to consecutive discarded data packets (e.g., the COUNT value with the smallest value among the COUNT values corresponding to consecutive discarded data packets), and the sixth discard state parameter is used to indicate the upper boundary of the COUNT value indicating consecutive discarded data packets (e.g., the COUNT value with the largest value among the COUNT values corresponding to consecutive discarded data packets). Then, the receiving end may update the state parameters of the receiving window based on the relationship between the fifth discard state parameter, the sixth discard state parameter, and RX_DELIV. Maintenance of the PDCP discard window In some embodiments, the PDCP discard window is used to indicate the packet with the smallest COUNT value corresponding to the discarded data packet, or the multiple consecutive discarded data packets where the packet with the smallest COUNT value corresponding to the discarded data packet is located. For example, assuming that the COUNT values corresponding to the discarded data packets are C2, C5, C8, and C9, then PDCPRX_Discard_High = PDCPRX_discard_low = C2. For another example, assuming that the COUNT values corresponding to the discarded data packets are C2, C3, C4, C8, and C9 (C2, C3, and C4 are consecutive COUNT values), then PDCPRX_Discard_High = C4 and PDCPRX_discard_low = C2. In some embodiments, if the receiving end has determined that there is PDCPRX_Discard_High, PDCPRX_discard_low, and the COUNT value (one COUNT value or multiple consecutive COUNT values) corresponding to the data packet requested to be discarded by the sending end is less than the current PDCPRX_discard_low, the receiving end can update PDCPRX_Discard_High to the upper boundary of the COUNT value corresponding to the data packet requested to be discarded, and update PDCPRX_discard_low to the lower boundary of the COUNT value corresponding to the data packet requested to be discarded. In some embodiments, if the receiving end has determined that there is PDCPRX_Discard_High, PDCPRX_discard_low, and the COUNT value (one COUNT value or multiple consecutive COUNT values) corresponding to the data packet requested to be discarded by the sending end is greater than the current PDCPRX_discard_low, the receiving end may not update PDCPRX_Discard_High and PDCPRX_discard_low. In some embodiments, if the receiving end has determined that there is PDCPRX_Discard_High, PDCPRX_discard_low, the COUNT value corresponding to the data packet requested to be discarded by the sending end overlaps with [PDCPRX_discard_low, PDCPRX_Discard_High] and can be superimposed into a continuous COUNT value interval, the receiving end can update PDCPRX_Discard_High to the upper boundary of the continuous COUNT value interval (the maximum value of the continuous COUNT value interval) and update PDCPRX_discard_low to the lower boundary of the continuous COUNT value interval (the minimum value in the continuous COUNT value interval). Exemplarily, FIG. 14A to FIG. 14E show schematic diagrams of a receiving end updating a PDCP discard window according to some embodiments of the present application. Assume that the receiving end has determined PDCPRX_Discard_High and PDCPRX_discard_low (hereinafter, the PDCP discard window corresponding to the determined PDCPRX_Discard_High and PDCPTX_discard_low is referred to as the current PDCP discard window), and the upper boundary of the COUNT value corresponding to the data packets requested to be discarded by the PDCP layer is C_high, and the lower boundary is C_low, where C_low ≤ C_high. The receiving end can update the state parameters of the PDCP discard window based on the relationship between C_high, C_low and the current PDCP discard window. Referring to Figure 14A, if C_high is less than PDCPRX_discard_low, it means that all COUNT values corresponding to the data packets requested to be discarded are less than PDCPRX_discard_low, and the data packets requested to be discarded do not overlap with the current discard window. The receiving end can update PDCPRX_discard_low to C_low and PDCPRX_discard_high to C_high. 14B , if C_low is greater than PDCPRX_discard_high, it means that all COUNT values corresponding to the packets requested to be discarded are greater than PDCPRX_discard_high, and the receiving end does not need to update the PDCP discard window. 14C , if C_high is greater than or equal to PDCPRX_discard_high and C_low is less than or equal to PDCPRX_discard_low, it indicates that the packet requested to be discarded includes the current PDCP discard window. The receiving end may update PDCPRX_discard_low to C_low and PDCPRX_discard_high to C_high. 14D , if C_high is greater than or equal to PDCPRX_discard_low and less than or equal to PDCPRX_discard_high, and C_low is less than PDCPRX_discard_low, it indicates that the packet requested to be discarded and the current PDCP discard window constitute new continuous packets, and the receiving end may update PDCPRX_discard_low to C_low. 14E , if C_low is greater than PDCPRX_discard_low and less than or equal to PDCPRX_discard_high, and C_high is greater than PDCPRX_discard_high, it indicates that the packet requested to be discarded and the current PDCP discard window constitute new continuous packets, and the receiving end may update PDCPRX_discard_high to C_high. In some embodiments, if the updated PDCP RX_discard_high is greater than RX_REORD, the receiving end may update RX_REORD to RX_NEXT. Here are some introductions: The process by which the receiving end updates the PDCP layer status parameters based on the PDCP discard window When the receiving end determines that the lower boundary of the PDCP discard window (PDCPRX_discard_low) is the same as the RX_DELIV of the PDCP layer, it can update RX_DELIV to the COUNT value after PDCPRX_discard_high. For example, RX_DELIV can be updated to the COUNT value after the COUNT value corresponding to PDCPRX_discard_high, or the COUNT value corresponding to the first data packet that the PDCP layer has not delivered to the upper layer and whose COUNT value is after the COUNT value corresponding to PDCPRX_discard_high. In some embodiments, after updating RX_DELIV, if there are still discarded packets with corresponding COUNT values between RX_DELIV and RX_NEXT, the receiving end may update or maintain PDCPRX_discard_low and PDCPRX_discard_high based on the existence of discarded packets. The specific update method can refer to the above content of maintaining the PDCP discard window and is not repeated here. In some embodiments, if the updated RX_DELIV is less than or equal to RX_REORD, the receiving end may not update RX_REORD. For example, referring to FIG13A , if PDCP RX_discard_high is less than RX_REORD and the updated RX_DELIV is less than or equal to RX_REORD, the receiving end may not update RX_REORD. In some embodiments, if the updated RX_DELIV is greater than RX_REORD, the receiving end may also update RX_REORD to RX_NEXT and start a reordering timer. For example, referring to FIG13B , if PDCP RX_discard_high is greater than or equal to RX_REORD, the updated RX_DELIV is greater than RX_REORD. The receiving end may also update RX_REORD to RX_NEXT and start a reordering timer. For another example, if PDCP RX_discard_high is less than RX_REORD, but the updated RX_DELIV is greater than RX_REORD, the receiving end may also update RX_REORD to RX_NEXT and start the reordering timer. In some embodiments, when RX_DELIV has been updated to COUNT after PDCPRX_discard_high, if there are still discarded data packets, the receiving end can update or establish a PDCP discard window based on the embodiments shown in Figures 14A to 14E, and update the status parameters of the PDCP layer based on the updated or established PDCP discard window. It can be seen from the above embodiments that the lower boundary of the receiving window will not be updated to the COUNT value corresponding to the discarded data packets. Communication method configuration process In some embodiments, the sending end and the receiving end can transmit information about turning on or off the functions corresponding to the communication method provided by the implementation of the present application based on the aforementioned control plane protocol framework, for example, information indicating turning on or off the function of discarding data packets that have been submitted to the lower layer, and updating the transmission status parameters (for example, the status parameters of the sending window, the status parameters of the receiving window, the status parameters of the PDCP layer, etc.) based on the discarded data packets. Exemplarily, a user equipment (UE) may obtain first indication information, where the first indication information is used to indicate whether to update a transmission state parameter based on a discarded data packet. When the first indication information indicates to update the transmission state parameter based on the discarded data packet, the user equipment discards the data packet that has been delivered to a lower layer. For example, the RLC layer of the user equipment may discard the data packet and update the transmission state parameter based on the method provided in each of the aforementioned embodiments. In some embodiments, referring to FIG. 15A , a network-side device (e.g., a base station (BS)) may configure first indication information for a user device. The first indication information may be configured in the context of an RLC entity configuration, for example, the first indication information may be included in RLC entity configuration parameters. The first indication information may be configured via MAC CE, PDCP layer signaling, RLC layer signaling, or RRC signaling. Furthermore, the first indication information may indicate which RLC entity may update transmission state parameters based on discarded data packets. For example, the first indication information may include an RLC entity identifier and indication information indicating whether to update transmission state parameters based on discarded data packets. In some embodiments, the first indication information may be an implicit indication, and the content of the first indication information may be obtained through other configuration information (for example, a discard indication based on a PDU set, or an indication of discarding a delivered data packet, or a discard indication based on the importance of a PDU set). In some embodiments, the network side device may further configure a duration (eg, a timer) for applying the first indication information, or a duration for discarding data packets that have been delivered to a lower layer. In some embodiments, referring to FIG15B , in a user device or a network side device, the PDCP layer may indicate first indication information to the RLC layer, and the PDCP layer indicates the first indication information when notifying the discard of a data packet. The conditions under which the PDCP layer indicates the first indication information to the RLC layer may include: the PDCP layer is configured with a discard indication based on the PDU set, and or the discard of the PDU set is executed; and or the PDCP layer is configured (for example, activated) with a discard indication based on the importance of the PDU set. The discard indication based on the PDU set is used to indicate that the discard of the PDU set is executed (for example, when a data packet in the PDU set is discarded, all data packets in the PDU set are discarded); the discard indication based on the importance of the PDU set is used to indicate that different discard timers are used according to the importance of different PDU sets. For example, when the PDU set corresponding to the data packet is a PDU set of the first importance, the first discard timer is started, and when the PDU set corresponding to the data packet is a PDU set of the second importance, the second discard timer is started. In some embodiments, referring to Figure 15B, in a user device or a network side device, the MAC layer may indicate first indication information to the RLC layer, wherein the condition for the MAC layer to indicate the first indication information to the RLC layer may include: the RLC entity is configured (for example, activated) a discard indication based on the importance of the PDU set. The technical solution of this application is described below with reference to the accompanying drawings. As previously described, in some embodiments, after determining to discard a packet to be discarded, the transmitting end may update the state parameters of the transmitting window and send discard information indicating the packet to be discarded to the receiving end. Correspondingly, after receiving the discard information, the receiving end may update the state parameters of the receiving window based on the discarded packet indicated by the discard information. For example, FIG16 shows a schematic diagram of an interaction process of a communication method according to some embodiments of the present application. As shown in FIG16 , the interaction process includes the following steps: S1601: The sending end discards the data packet to be discarded. Exemplarily, when the sending end determines that the data packet to be discarded meets the aforementioned discarding condition, the sending end may discard the data packet to be discarded. In some embodiments, corresponding to the RLC layer of the transmitting end, the discard condition may include that the first RLC SN corresponding to packet A (the packet to be discarded) satisfies the following conditions: TX_Next_Ack ≤ first RLC SN ≤ TX_Next. The transmitting end may discard packet A if the first RLC SN satisfies TX_Next_Ack ≤ first RLC SN ≤ TX_Next; otherwise, no processing is performed. It should be understood that in other embodiments, the discarding condition may include other conditions, which are not limited here. In some embodiments, the transmitting end may discard the data packet to be discarded when receiving the aforementioned first indication information and the first indication information indicates discarding the data packet to be discarded. S1602: The sending end updates the state parameters of the sending window. For example, after discarding a packet to be discarded, the sender may update the state parameters of the send window based on the discarded packet. The specific manner in which the sender updates the send window may include the aforementioned sender state parameter updating process, the sender discard window maintenance process, and the sender updating the send window state parameters based on the sender discard window state parameters, and are not further described here. In some embodiments, the transmitting end may update the state parameters of the sending window based on the discarded data packets if the discarded data packets meet the aforementioned update conditions. In some embodiments, for the RLC layer of the transmitting end, the update condition may include that the first RLC SN corresponding to data packet A (as the discarded data packet) satisfies the following conditions: TX_Next_Ack ≤ first RLC SN ≤ TX_Next. The transmitting end may update the state parameters of the transmit window (e.g., TX_Next_Ack, etc.) if the first RLC SN satisfies TX_Next_Ack ≤ first RLC SN ≤ TX_Next; otherwise, no processing is performed. In some embodiments, the transmitting end may update the state parameters of the sending window when receiving the aforementioned first indication information, and the first indication information indicates to update the state parameters of the sending window based on the discarded data packets. S1603: The sending end sends discard information to the receiving end. The sending end may send discard information indicating discarded data packets (eg, data packets that have been discarded and / or are to be discarded by the sending end) to the receiving end. In some embodiments, the discard information may be used to indicate data packets that have been discarded and / or are to be discarded by the transmitting end. For example, the discard information may include identifiers of the RLC SDUs or RLC PDUs or PDCP SDUs or PDCP PDUs corresponding to the data packets that have been discarded and / or are to be discarded by the transmitting end, such as the RLC SN, PDCP SN, or COUNT value of the PDCP layer. It should be understood that in other embodiments, the discard information may also be in other forms that can enable the receiving end to determine the discarded data packet, which is not limited here. S1604: The receiving end updates the transmission state parameters based on the discard information. After receiving the discard information, the receiving end may update transmission state parameters, such as state parameters of the receiving window and state parameters of the PDCP layer, based on the discarded data packets indicated by the discard information. In some embodiments, the receiving end may update the state parameters of the receiving window and the state parameters of the PDCP layer when the discarded data packets meet the aforementioned update conditions. In some embodiments, corresponding to the RLC layer of the receiving end, the update condition may include that the second RLC SN corresponding to data packet B (a discarded data packet, such as a data packet that has been discarded and / or is to be discarded by the sending end, data packet B may be an RLC SDU or RLC PDU) satisfies: RX_Next≤second RLC SN≤RX_Next_Highest. In some embodiments, corresponding to the RLC layer of the receiving end, the update condition may include that the second RLC SN corresponding to the data packet B satisfies: RX_Next≤second RLC SN≤RX_Highest_status. In some embodiments, corresponding to the RLC layer of the receiving end, the update condition may include that the second RLC SN corresponding to the data packet B satisfies: RX_Next≤second RLC SN≤RX_Next_status_trigger. In some embodiments, corresponding to updating the state parameters of the PDCP layer, the update condition may include that a first COUNT value of the PDCP SDU corresponding to the packet A (as the packet to be discarded) satisfies: RX_DELIV≤first COUNT value≤RX_NEXT. In some embodiments, the specific process of the receiving end updating the state parameters of the receiving window can refer to the aforementioned process of the receiving end updating the state parameters, the process of the receiving end updating the state parameters of the RLC layer, the maintenance process of the receiving end discarding the window, and the process of the receiving end updating the state parameters of the receiving window based on the state parameters of the receiving end discarding the window. No further details will be given here. In some embodiments, the specific process of the receiving end updating the status parameters of the PDCP layer can refer to the aforementioned process of the receiving end updating the status parameters, the process of the receiving end updating the status parameters of the PDCP layer, the maintenance of the PDCP discard window, and the process of the receiving end updating the status parameters of the PDCP layer according to the PDCP discard window, which will not be repeated here. In some embodiments, the receiving end may update the state parameters of the receiving window when receiving the aforementioned first indication information, and the first indication information indicates to update the state parameters of the receiving window based on the discarded data packets. In some embodiments, the receiving end may update the state parameters of the PDCP layer when the aforementioned first indication information is received and the first indication information indicates that the state parameters of the PDCP layer are updated based on the discarded data packets. In some embodiments, the specific form of the first indication information, the way in which the receiving end receives the first indication information, etc. can refer to the content of the configuration part of the aforementioned communication method, and will not be repeated here. It should be understood that the execution order of the aforementioned steps S1601 to S1604 is only an example. In other embodiments, the execution order of some steps can be adjusted, and some steps can be merged or split, which is not limited here. For example, in some embodiments, step S1602 and step S1603 can be performed simultaneously, and the execution order can be adjusted. For another example, step S1604 can be executed before step S1603, or it can be executed in parallel with step S1604, which is not limited here. For another example, step S1601 and step S1603 can be merged and executed, and step S1602 and step S1604 can be executed in parallel. In some embodiments, the aforementioned steps S1601 to S1604 may be implemented by the RLC layer of the transmitting end and the receiving end. Based on the above method, the sender and the receiver can adjust the state parameters of the sending window and the receiving window in time when the discarded data packets have been submitted to the lower layer, avoiding the retransmission of the discarded data packets and the freezing of the receiving window, which is beneficial to improving the communication quality between the sender and the receiver. In some embodiments, after determining to discard a packet to be discarded, the transmitting end may send discard information indicating the discarded packet to the receiving end. After receiving the discard information, the receiving end may update the state parameters of the receiving window based on the discarded packet indicated by the discard information and send an ACK to the transmitting end indicating that all discarded packets have been completely received. Accordingly, after receiving the ACK indicating that all discarded packets have been completely received, the transmitting end may update the state parameters of the sending window based on the existing protocol framework. For example, FIG17 shows a schematic diagram of an interaction process of a communication method according to some embodiments of the present application. As shown in FIG17 , the interaction process includes the following steps: S1701: The sending end discards the data packet to be discarded. For details, please refer to the aforementioned step S1601 and will not be described in detail here. S1702: The sending end sends discard information to the receiving end. After discarding the data packets to be discarded, the sending end may send discard information indicating the discarded data packets (eg, data packets that have been discarded and / or are to be discarded by the sending end) to the receiving end. In some embodiments, the discard information may be used to indicate discarded data packets. For example, the discard information may include identifiers of RLC SDUs, RLC PDUs, PDCP SDUs, or PDCP PDUs corresponding to data packets discarded and / or to be discarded by the transmitting end, such as RLC SNs, PDCP SNs, or PDCP layer COUNT values. It should be understood that in other embodiments, the discard information may also be other forms of information, which is not limited here. S1703: The receiving end updates the transmission state parameters based on the discard information. After receiving the discard information, the receiving end can update the transmission status parameters (such as the status parameters of the receiving window, the status parameters of the PDCP layer, etc.) based on the discard information (such as the discarded data packet indicated by the discard information). For details, please refer to the content of the aforementioned step S1604, which will not be repeated here. S1704: The receiving end sends a status report to the sending end. The receiving end may also send a status report to the transmitting end, indicating that all packets corresponding to the discarded packet have been received. When updating the transmission status parameters based on the discard information, the receiving end may trigger a status report. The process and method for triggering the status report by the receiving end can be referred to in the aforementioned process of the receiving end sending a status report to the transmitting end, and will not be further described here. In some embodiments, if ACKs for all data packets corresponding to the discarded data packets have been sent to the transmitting end, the receiving end may not send a status report. In some embodiments, if ACKs for some data packets among the data packets corresponding to the discarded data packets have been sent to the transmitting end, ACKs for these data packets may not be included in the status report. In some embodiments, if NACKs for some data packets among the data packets corresponding to the discarded data packets have been sent to the transmitting end, the receiving status of these data packets may be ACK in the status report. S1705: The sending end updates the status parameters of the sending window based on the status report. After receiving the status report, the sender can update the state parameters of the sending window based on the relevant protocol (such as TS28.322 protocol). For details, please refer to the description of the relevant protocol and will not be repeated here. In some embodiments, the order of step S1704 and step S1705 can be swapped or performed in parallel, which is not limited here. The present application also provides a communication method, which is applied to a transmitting end. Referring to FIG. 18 , the method includes the following steps: S1801: discard the data packet to be discarded. For example, after receiving a discard request from an upper layer (eg, a PDCP layer), the transmitting end (eg, the RLC layer of the transmitting end) may discard the data packet to be discarded. Detailed information may be referred to the aforementioned step S1601 and will not be described in detail here. S1802: Update the status parameters of the sending window. For example, after discarding the data packet to be discarded, the transmitting end (eg, the RLC layer of the transmitting end) may update the state parameter of the transmitting window based on the discarded data packet. S1803, sending discard information to the receiving end The sending end sends discard information to the receiving end, where the discard information is used to indicate discarded data packets (eg, data packets discarded and / or to be discarded by the sending end) and instruct the receiving end to update transmission state parameters based on the discard information. In some embodiments, the discard information may be used to indicate discarded data packets. For example, the discard information may include identifiers of RLC SDUs, RLC PDUs, PDCP SDUs, or PDCP PDUs corresponding to data packets discarded and / or to be discarded by the transmitting end, such as RLC SNs, PDCP SNs, or PDCP layer COUNT values. It should be understood that the discard information can be any information that can indicate a discarded data packet, and the embodiment of the present application does not limit the specific form of the discard information. In some embodiments, the discard information may be used to instruct the RLC layer of the receiving end to update the state parameters of the receiving window, and / or instruct the PDCP layer of the receiving end to update the state parameters of the PDCP layer. Based on the above embodiment, the transmitting end can promptly update the state parameters of the transmit window based on discarded data packets, thereby preventing the transmitting end from transmitting or retransmitting the discarded data packets. Furthermore, the transmitting end may instruct the receiving end to promptly update the state parameters of the receive window and / or the state parameters of the PDCP layer through discard information, thereby preventing receive window freeze or PDCP layer data reception failure caused by untimely parameter updates, thereby improving communication quality. The present application also provides a communication method, which is applied to a receiving end. Referring to FIG. 19 , the method includes the following steps: S1901: Receive discard information sent by the sending end. Exemplarily, the receiving end may receive discard information sent by the transmitting end (eg, the RLC layer, PDCP layer, MAC layer, PHY layer, etc. of the transmitting end). In some embodiments, the discard information may be used to indicate discarded data packets (e.g., data packets discarded and / or to be discarded by the transmitting end). For example, the discard information may include identifiers of the RLC SDUs or RLC PDUs or PDCP SDUs or PDCP PDUs corresponding to the data packets discarded and / or to be discarded by the transmitting end, such as the RLC SN, PDCP SN, or COUNT value of the PDCP layer. It should be understood that the discard information can be any information that can indicate a discarded data packet, and the embodiment of the present application does not limit the specific form of the discard information. S1902: Update transmission status parameters based on the discard information. After receiving the discard information, the receiving end may determine the discarded data packet indicated by the discard information, and update the transmission state parameter based on the discarded data packet. For example, the receiving end may determine the RLC SDU or RLC PDU corresponding to the discarded data packet indicated by the discard information, and update the state parameters of the receiving window based on the RLC SDU or RLC PDU corresponding to the discarded data packet. For details, please refer to the aforementioned process of updating the state parameters by the receiving end, the process of updating the state parameters of the RLC layer by the receiving end, the process of maintaining the discard window by the receiving end, and the process of updating the state parameters of the receiving window by the receiving end based on the state parameters of the discard window by the receiving end, which will not be described in detail here. For example, the receiving end may determine the PDCP SDU or PDCP PDU corresponding to the discarded data packet indicated by the discard information, and update the state parameters of the PDCP layer based on the PDCP SDU or PDCP PDU corresponding to the discarded data packet. For details, please refer to the aforementioned process of updating the state parameters by the receiving end, the process of updating the state parameters of the PDCP layer by the receiving end, the maintenance of the PDCP discard window, and the process of updating the state parameters of the PDCP layer by the receiving end according to the PDCP discard window, which will not be described in detail here. Based on the above embodiments, the receiving end can timely update the status parameters of the receiving window and / or the status parameters of the PDCP layer based on the discarded data packets, thereby avoiding receiving window deadlock or PDCP layer data reception failure due to failure to update the parameters in a timely manner, which is conducive to improving communication quality. The present application also provides a communication method, which is applied to a receiving end. Referring to FIG. 20 , the method includes the following steps: S2001: Receive discard information sent by the sending end. Exemplarily, the receiving end may receive discard information sent by the transmitting end (eg, the RLC layer, PDCP layer, MAC layer, PHY layer, etc. of the transmitting end). In some embodiments, the discard information may be used to indicate discarded data packets (e.g., data packets discarded and / or to be discarded by the transmitting end). For example, the discard information may include identifiers of the RLC SDUs or RLC PDUs or PDCP SDUs or PDCP PDUs corresponding to the data packets discarded and / or to be discarded by the transmitting end, such as the RLC SN, PDCP SN, or COUNT value of the PDCP layer. It should be understood that the discard information can be any information that can indicate a discarded data packet, and the embodiment of the present application does not limit the specific form of the discard information. S2002: Update transmission status parameters based on the discard information. After receiving the discard information, the receiving end may determine the discarded data packet indicated by the discard information, and update the transmission state parameter based on the discarded data packet. For example, the receiving end may determine the RLC SDU or RLC PDU corresponding to the discarded data packet indicated by the discard information, and update the state parameters of the receiving window based on the RLC SDU or RLC PDU corresponding to the discarded data packet. For details, please refer to the aforementioned process of updating the state parameters by the receiving end, the process of updating the state parameters of the RLC layer by the receiving end, the process of maintaining the discard window by the receiving end, and the process of updating the state parameters of the receiving window by the receiving end based on the state parameters of the discard window by the receiving end, which will not be described in detail here. For example, the receiving end may determine the PDCP SDU or PDCP PDU corresponding to the discarded data packet indicated by the discard information, and update the state parameters of the PDCP layer based on the PDCP SDU or PDCP PDU corresponding to the discarded data packet. For details, please refer to the aforementioned process of the receiving end updating the state parameters, the process of the receiving end updating the state parameters of the PDCP layer, the maintenance of the PDCP discard window, and the process of the receiving end updating the state parameters of the PDCP layer according to the PDCP discard window, which will not be repeated here. S2003: Send a status report to the sending end. Illustratively, after updating the state parameters of the receiving window, the receiving end may send a status report to the sending end, where the status report is used to indicate that the discarded data packet indicated by the discard information has been received by the receiving end. The process and method of triggering the status report by the receiving end can refer to the content of the process of sending the status report from the receiving end to the sending end mentioned above, which will not be repeated here. In some embodiments, if ACKs for all data packets corresponding to the discarded data packets have been sent to the transmitting end, the receiving end may not send a status report. In some embodiments, if ACKs for some data packets among the data packets corresponding to the discarded data packets have been sent to the transmitting end, ACKs for these data packets may not be included in the status report. In some embodiments, if NACKs for some data packets among the data packets corresponding to the discarded data packets have been sent to the transmitting end, the receiving status of these data packets may be ACK in the status report. It should be understood that after receiving the status report, the sender can update its state parameters based on the status report, such as updating the state parameters of the send window. Since the discarded data packets indicated by the discard information have all been confirmed received by the receiver (in practice, the receiver may not have received the data packets but only sent an ACK), the sender will not retransmit these data packets, which is beneficial to improving communication quality. The communication method provided in the embodiment of the present application can be applied to scenarios such as audio stream data, video stream data or picture data transmission between the sending end and the receiving end under audio, video, picture and other services, such as XR scenarios. The data packet discarding method provided in the embodiment of the present application can be applied to various types of communication systems, such as the fifth generation (5G) th In addition, it can also be applied to universal mobile telecommunications system (UMTS), wireless local area network (WLAN), wireless fidelity (Wi-Fi) system, wired system, vehicle to everything (V2X) communication system, device-to-device (D2D) communication system, fourth generation (4G) th generation, 4G) mobile communication systems, satellite communication systems, and future communication systems such as the sixth generation (6 th Generation, 6G) mobile communication system, etc. The embodiments of the present application are not limited to this. 21 is a schematic diagram of a system architecture 10 applicable to a communication method provided in an embodiment of the present application. The system architecture includes a transmitting device 100 and a receiving device 200 (or a transmitting end and a receiving end). In some embodiments, the transmitting device 100 may serve as a transmitting end for data packet transmission, and the receiving device 200 may serve as a receiving end for data packet transmission. In some embodiments, the transmitting device 100 can be a variety of user devices, such as mobile phones, tablet computers, wearable devices, in-vehicle devices, augmented reality (AR) / virtual reality (VR) devices, cloud gaming (CG) devices, mixed reality (MR) devices, laptop computers, ultra-mobile personal computers (UMPCs), netbooks, personal digital assistants (PDAs), and other devices with audio / video and communication functions. The embodiments of the present application do not limit the type of the transmitting device. In some embodiments, the receiving device 200 may be a network device / core network device, for example, an access device for the transmitting device 100 to access the wireless communication system in a wireless manner. The receiving device 200 may be an entity on the network side for transmitting or receiving signals, such as a base station. A base station may broadly cover various names as follows, or be replaced with the following names, such as: NodeB, evolved NodeB (eNB), next generation NodeB (gNB), relay station, access point, transmission point (TRP), transmitting point (TP), master station, auxiliary station, multi-standard wireless node, home base station, network controller, access node, access point, transmission node, transceiver node, baseband unit, radio frequency remote unit, active antenna unit, radio frequency head, central unit, distribution unit, positioning node, etc. A base station may be a macro base station, a micro base station, a relay node, a donor node, or the like. A base station may also be used for a communication module, a modem, or a chip provided in the aforementioned device or apparatus. The base station may also be a mobile switching center and a device that performs base station functions in device-to-device, vehicle-to-vehicle, and machine-to-machine communications. The embodiments of the present application do not limit the specific technology and specific device form used by the network device. In some embodiments, the transmitting device 100 may be a network device / core device, and correspondingly, the receiving device 200 may be a user device. For example, as shown in FIG22 , it is a structural diagram of a sending end device 100 provided in an embodiment of the present application. The sending device 100 may include a processor 110, an external memory interface 120, an internal memory 121, a universal serial bus (USB) interface 130, a charging management module 140, a power management module 141, a battery 142, an antenna 1, an antenna 2, a mobile communication module 150, a wireless communication module 160, an audio module 170, a speaker 170A, a receiver 170B, a microphone 170C, an earphone interface 170D, a sensor module 180, a button 190, a motor 191, an indicator 192, a camera 193, a display screen 194, and a subscriber identification module (SIM) card interface 195, etc. It is understandable that the structure illustrated in the embodiments of the present application does not constitute a specific limitation on the sending end device 100. In other embodiments of the present application, the sending end device 100 may include more or fewer components than shown in the figure, or combine certain components, or split certain components, or arrange the components differently. The illustrated components can be implemented in hardware, software, or a combination of software and hardware. In addition, the interface connection relationship between the modules illustrated in the embodiments of the present application is for schematic illustration only and does not constitute a structural limitation on the sending end device 100. In other embodiments of the present application, the sending end device 100 may also adopt an interface connection method different from that in the above-mentioned embodiments, or a combination of multiple interface connection methods. The processor 110 may include one or more processing units. For example, the processor 110 may include an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, a memory, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural-network processing unit (NPU). The different processing units may be independent devices or integrated into one or more processors. The controller may be the nerve center and command center of the transmitting device 100. The controller may generate an operation control signal based on the instruction operation code and the timing signal to complete the control of instruction fetching and execution. Processor 110 may also include a memory for storing instructions and data. In some embodiments, the memory in processor 110 is a cache memory. This memory can store instructions or data that have just been used or are being recycled by processor 110. If processor 110 needs to use the same instruction or data again, it can directly access the memory. This avoids duplicate accesses, reduces processor 110 latency, and thus improves system efficiency. The charging management module 140 is used to receive charging input from the charger. The power management module 141 is used to connect the battery 142, the charging management module 140 and the processor 110. The power management module 141 receives input from the battery 142 and / or the charging management module 140, and provides power to the processor 110, the internal memory 121, the external memory, the display 194, the camera 193, and the wireless communication module 160. The power management module 141 can also be used to monitor parameters such as battery capacity, battery cycle count, battery health status (leakage, impedance), etc. In some other embodiments, the power management module 141 can also be set in the processor 110. In other embodiments, the power management module 141 and the charging management module 140 can also be set in the same device. The wireless communication function of the transmitting device 100 can be implemented through antenna 1, antenna 2, mobile communication module 150, wireless communication module 160, modem processor and baseband processor. Antenna 1 and Antenna 2 are used to transmit and receive electromagnetic wave signals. Each antenna in transmitting device 100 can be used to cover a single or multiple communication frequency bands. Different antennas can also be reused to improve antenna utilization. For example, antenna 1 can be reused as a diversity antenna for a wireless local area network. In other embodiments, the antennas can be used in conjunction with a tuning switch. The mobile communication module 150 can provide wireless communication solutions including 2G / 3G / 4G / 5G applied on the transmitting end device 100. The wireless communication module 160 can provide wireless communication solutions including wireless local area networks (WLAN) (such as wireless fidelity (Wi-Fi) networks), Bluetooth (BT), global navigation satellite system (GNSS), frequency modulation (FM), near field communication (NFC), infrared (IR), etc., which are applied to the sending end device 100. The wireless communication module 160 can be one or more devices that integrate at least one communication processing module. The wireless communication module 160 receives electromagnetic waves via the antenna 2, frequency modulates and filters the electromagnetic wave signals, and sends the processed signals to the processor 110. The wireless communication module 160 can also receive the signal to be sent from the processor 110, frequency modulate it, amplify it, and convert it into electromagnetic waves for radiation through the antenna 2. In some embodiments, antenna 1 of the transmitting device 100 is coupled to the mobile communication module 150, and antenna 2 is coupled to the wireless communication module 160, so that the transmitting device 100 can communicate with the network and other devices through wireless communication technology. The wireless communication technology may include global system for mobile communications (GSM), general packet radio service (GPRS), code division multiple access (CDMA), wideband code division multiple access (WCDMA), time-division code division multiple access (TD-SCDMA), long term evolution (LTE), BT, GNSS, WLAN, NFC, FM, and / or IR technology. The GNSS may include a global positioning system (GPS), a global navigation satellite system (GLONASS), a Beidou navigation satellite system (BDS), a quasi-zenith satellite system (QZSS) and / or a satellite based augmentation system (SBAS). The transmitting end device 100 implements a display function through a GPU, a display screen 194, and an application processor, etc. The display screen 194 is used to display images, videos, etc. The external memory interface 120 can be used to connect an external memory card, such as a Micro SD card, to expand the storage capacity of the transmitting device 100. The external memory card communicates with the processor 110 via the external memory interface 120 to implement data storage functions. For example, files such as music and videos can be stored on the external memory card. The internal memory 121 can be used to store computer executable program codes, which include instructions. The internal memory 121 may include a program storage area and a data storage area. The program storage area may store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc. The data storage area may store data created during the use of the sending device 100 (such as audio data, a phone book, etc.). In addition, the internal memory 121 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device. Flash memory device, universal flash storage (UFS), etc. The processor 110 executes various functional applications and data processing of the sending device 100 by running instructions stored in the internal memory 121 and / or instructions stored in a memory provided in the processor. The transmitting device 100 can implement audio functions such as music playback and recording through the audio module 170, the speaker 170A, the receiver 170B, the microphone 170C, the headphone jack 170D, and the application processor. In some embodiments, the receiving device 200 may adopt a structure similar to or the same as that of the transmitting device 100, or may adopt a different structure, which is not limited here. Based on the same technical concept, an embodiment of the present application also provides a sending end device, including one or more processors; one or more memories; the one or more memories store one or more computer programs, and the one or more computer programs include instructions. When the instructions are executed by the one or more processors, the sending end device executes one or more steps in any of the above methods. Based on the same technical concept, an embodiment of the present application also provides a communication system, including a sending end device and a receiving end device, wherein the sending end device is used to execute one or more steps in any of the above methods, and the receiving end is used to receive the data packet in the protocol data unit set transmitted by the sending end. Based on the same technical concept, an embodiment of the present application also provides a computer-readable storage medium, which stores computer-executable program instructions. When the computer-executable program instructions are executed on a computer, the computer or processor executes one or more steps in any of the above methods. Based on the same technical concept, an embodiment of the present application also provides a computer program product containing instructions, wherein the computer program product includes computer program code. When the computer program code is run on a computer, the computer or processor executes one or more steps in any of the above methods. It should be noted that, in the embodiments of the present application, the description of the numerical range, such as A is between B and C, may include endpoints (e.g., B, C) or not. That is, "A is between B and C" may be B <a<c，也可以是b≤a<c，还可以是b≤a≤c、b<a≤c。In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted via the computer-readable storage medium. The computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid state drive (SSD)). Those skilled in the art will appreciate that all or part of the process steps in the above-described method embodiments can be implemented by a computer program instructing the relevant hardware. The program can be stored in a computer-readable storage medium, and when executed, the program can include the process steps in the above-described method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM or random access memory (RAM), magnetic disks, or optical disks. The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A communication method, applied to a transmitting end, comprising: Identify dropped packets; The transmission state parameters of the sending end are updated based on the discarded data packets.

2. The method according to claim 1, characterized in that The transmission state parameter of the sending end includes a first state parameter, and the first state parameter is used to indicate the sequence number of the next data packet to be confirmed for reception by the sending end.

3. The method according to claim 2, characterized in that The discarded data packet meets the first condition; The first condition includes: The discarded data packets are within the sending window; or the sequence number of the discarded data packet is between the sequence number indicated by the first status parameter and the sequence number of the next data packet sent by the sender; or the sequence number of the discarded data packet is greater than or equal to the sequence number indicated by the first status parameter; Or the sequence number of the discarded data packet is less than or equal to the sequence number of the next data packet sent by the sending end.

4. The method according to claim 2 or 3, characterized in that The updating of the transmission state parameter of the transmitting end based on the discarded data packet includes: If the discarded data packet meets the second condition, updating the transmission state parameter of the transmitting end based on the discarded data packet; The second condition includes: The discarded data packets are within the sending window; or the sequence number of the discarded data packet is between the sequence number indicated by the first status parameter and the sequence number of the next data packet sent by the sender; or the sequence number of the discarded data packet is greater than or equal to the sequence number indicated by the first status parameter; Or the sequence number of the discarded data packet is less than or equal to the sequence number of the next data packet sent by the sending end.

5. The method according to claim 2, characterized in that The updating of the transmission state parameter of the transmitting end based on the discarded data packet includes: If there is a first data packet whose sequence number is the same as the sequence number indicated by the first state parameter among the discarded data packets, updating the first state parameter to a second sequence number following the first sequence number of the first data packet; Alternatively, corresponding to the absence of a data packet having a sequence number identical to the sequence number indicated by the first state parameter among the discarded data packets, when the first state parameter is updated to the first sequence number, the first state parameter is updated to the second sequence number.

6. The method according to claim 3 or 4, characterized in that The updating of the transmission state parameter of the transmitting end based on the discarded data packet includes: If the sequence number indicated by the first state parameter is the same as the first sequence number of the first data packet among the discarded data packets, updating the first state parameter to a second sequence number following the first sequence number, wherein the first data packet is the data packet with the smallest sequence number among the discarded data packets; Alternatively, the sequence number indicated by the first state parameter is different from the first sequence number. When the first state parameter is updated to the first sequence number, the first state parameter is updated to the second sequence number.

7. The method according to claim 5 or 6, characterized in that The discarded data packets include first consecutive data packets, the first consecutive data packets include the first data packet, and the second sequence number is a sequence number of a second data packet following the first consecutive data packet.

8. The method according to claim 7, characterized in that The second data packet is the next data packet of the first continuous data packet, or the first data packet after the first continuous data packet that has not received confirmation feedback, or the first data packet after the first continuous data packet that has not received confirmation feedback and is not among the discarded data packets.

9. The method according to claim 7, characterized in that The first sequence number and a third sequence number corresponding to the last data packet in the first continuous data packets are maintained based on a first discard state parameter and a second discard state parameter, respectively.

10. The method according to claim 9, characterized in that The method further comprises: At least one consecutive data packet that is discarded is determined, and a first discard state parameter and a second discard state parameter are updated based on the at least one consecutive data packet that is discarded.

11. The method according to claim 10, characterized in that The maximum value of the sequence numbers corresponding to the at least one consecutive data packet is the fourth sequence number, and the minimum value is the fifth sequence number, and the fourth sequence number is greater than or equal to the fifth sequence number; and updating the first discard state parameter and the second discard state parameter based on the discarded at least one consecutive data packet includes: corresponding to the fourth sequence number being less than the first discard state parameter, updating the first discard state parameter to the fifth sequence number and updating the second discard state parameter to the fourth sequence number; or corresponding to the fourth sequence number being greater than the second discard state parameter, and the fifth sequence number being greater than or equal to the first discard state parameter and less than or equal to the second discard state parameter, updating the second discard state parameter to the fourth sequence number; or corresponding to the fourth sequence number being less than or equal to the second discard state parameter and greater than or equal to the first state parameter, and the fifth sequence number being less than the first discard state parameter, updating the first discard state parameter to the fifth sequence number; or corresponding to the fourth sequence number being less than or equal to the second discard state parameter and greater than or equal to the first state parameter, and the fifth sequence number being less than the first discard state parameter, updating the first discard state parameter to the fifth sequence number; Alternatively, corresponding to the fourth sequence number and the fifth sequence number being between the first discard state parameter and the second discard state parameter, or the fifth sequence number being greater than the second discard state parameter, the first discard state parameter and the second discard state parameter are not updated.

12. The method according to any one of claims 1 to 11, characterized in that The method further comprises: Sending discard information to the receiving end, where the discard information is used to indicate the discarded data packet.

13. The method according to claim 1, wherein The above method further includes: receiving first instruction information; The discarded data packet is discarded in response to the first indication information.

14. A communication method, applied to a receiving end, characterized in that: include: Identify dropped packets; The transmission state parameters of the receiving end are updated based on the discarded data packets.

15. The method according to claim 14, characterized in that The transmission status parameter of the receiving end includes at least one of the following parameters: A second state parameter, wherein the second state parameter is used to indicate a sequence number of a next data packet after the data packet most recently received in sequence and in full by the receiving end; A third state parameter, wherein the third state parameter is used to indicate a sequence number of a next data packet after the most recently completely received data packet by the receiving end; A fourth state parameter, where the fourth state parameter is used to indicate a next sequence number of a sequence number corresponding to a data packet that triggers a reassembly timer.

16. The method according to claim 15, characterized in that The updating of the transmission state parameter of the receiving end based on the discarded data packet includes: If the discarded data packet meets a third condition, updating a transmission state parameter of the receiving end based on the discarded data packet; The third condition includes: The discarded data packets are within the receiving window; or the sequence number of the discarded data packet is between the sequence number indicated by the second status parameter and the largest sequence number of the sequence numbers of the data packets completely received by the receiving end; or the sequence number of the discarded data packet is between the sequence number indicated by the second status parameter and the sequence number indicated by the third status parameter; or the sequence number of the discarded data packet is between the sequence number indicated by the second status parameter and the sequence number indicated by the fourth status parameter; or the sequence number of the discarded data packet is greater than or equal to the sequence number indicated by the second status parameter; Or the sequence number of the discarded data packet is less than or equal to the largest sequence number among the sequence numbers of the data packets completely received by the receiving end; Or the sequence number of the discarded data packet is less than or equal to the sequence number indicated by the third status parameter; Or the sequence number of the discarded data packet is less than or equal to the sequence number indicated by the fourth status parameter.

17. The method according to claim 15, characterized in that The updating of the transmission state parameter of the receiving end based on the discarded data packet includes: If there is a third data packet whose sequence number is the same as the sequence number indicated by the second state parameter among the discarded data packets, updating the second state parameter to the seventh sequence number following the sixth sequence number of the third data packet; Alternatively, corresponding to the absence of a data packet with a sequence number identical to the sequence number indicated by the second state parameter among the discarded data packets, when the second state parameter is updated to the sixth sequence number, the second state parameter is updated to the seventh sequence number.

18. The method according to claim 16, characterized in that The updating of the transmission state parameter of the receiving end based on the discarded data packet includes: If the sequence number indicated by the second state parameter is the same as the sixth sequence number of the third data packet among the discarded data packets, updating the second state parameter to the seventh sequence number following the sixth sequence number, wherein the third data packet is the data packet with the smallest sequence number among the discarded data packets; Alternatively, the sequence number indicated by the second state parameter is different from the sixth sequence number. When the second state parameter is updated to the sixth sequence number, the second state parameter is updated to the seventh sequence number.

19. The method according to claim 17 or 18, characterized in that The discarded data packets include second consecutive data packets, the second consecutive data packets include the third data packet, and the seventh sequence number is the sequence number of the fourth data packet after the second consecutive data packet.

20. The method according to claim 19, characterized in that The fourth data packet is the next data packet of the second continuous data packet, or the first incompletely received data packet after the second continuous data packet, or the first incompletely received data packet after the second continuous data packet and not in the discarded data packets.

21. The method according to claim 17 or 18, characterized in that The discarded data packets include a second continuous data packet, and the second continuous data packets include the third data packet; and updating the transmission state parameter of the receiving end based on the discarded data packets further includes: If the sequence number of the last data in the second continuous data packets is greater than or equal to the sequence number indicated by the third state parameter, updating the third state parameter to an eighth sequence number; and / or when the sequence number of the last data in the second continuous data packets is greater than or equal to the sequence number corresponding to the fourth state parameter, updating the fourth state parameter to a sequence number next to the largest sequence number among the sequence numbers of the data packets completely received by the receiving end; The eighth serial number is the serial number of the fifth data packet after the second continuous data packet, and the fifth data packet is the next data packet after the second continuous data packet, or the first incompletely received data packet after the second continuous data packet.

22. The method according to claim 19, wherein The method further comprises: A status report is sent to the sending end, where the status report is used to indicate that all data packets in the second continuous data packets have been completely received by the receiving end.

23. The method according to claim 22, characterized in that The sending of the report to the transmitting end includes: In a case where the acknowledgement feedback ACK of one or more data packets in the second consecutive data packets is not sent to the transmitting end, the status report is sent to the transmitting end, where the status report includes the ACK of the one or more data packets.

24. The method according to claim 19, wherein The sixth sequence number and a ninth sequence number corresponding to the last data packet in the second continuous data packets are maintained based on a third discard state parameter and a fourth discard state parameter, respectively.

25. The method according to claim 24, characterized in that The method further comprises: At least one consecutive data packet that is discarded is determined, and a third discard state parameter and a fourth discard state parameter are updated based on the at least one consecutive data packet that is discarded.

26. The method according to claim 25, characterized in that The maximum value of the sequence numbers corresponding to the at least one consecutive data packet is the tenth sequence number, and the minimum value is the eleventh sequence number, and the tenth sequence number is greater than or equal to the eleventh sequence number; and updating the third discard state parameter and the fourth discard state parameter based on the discarded at least one consecutive data packet includes: corresponding to the tenth sequence number being less than the third discard state parameter, updating the third discard state parameter to the eleventh sequence number and updating the fourth discard state parameter to the tenth sequence number; or corresponding to the tenth sequence number being greater than the fourth discard state parameter, and the eleventh sequence number being greater than or equal to the third discard state parameter and less than or equal to the discard state parameter, updating the fourth discard state parameter to the tenth sequence number; or corresponding to the tenth sequence number being less than or equal to the fourth discard state parameter and greater than or equal to the third state parameter, and the eleventh sequence number being less than the third discard state parameter, updating the third discard state parameter to the eleventh sequence number; or corresponding to the tenth sequence number being less than or equal to the fourth discard state parameter and greater than or equal to the third state parameter, and the eleventh sequence number being less than the third discard state parameter, updating the third discard state parameter to the eleventh sequence number; Alternatively, corresponding to the tenth sequence number and the eleventh sequence number being between the third discard state parameter and the fourth discard state parameter, or the eleventh sequence number being greater than the fourth discard state parameter, the third discard state parameter and the fourth discard state parameter are not updated.

27. The method according to any one of claims 15 to 26, characterized in that The receiving end includes a radio link control layer, and the radio link control layer: Identify dropped packets; The transmission state parameters of the receiving end are updated based on the discarded data packets.

28. The method according to claim 14, wherein The transmission status parameter of the receiving end includes at least one of the following parameters: a fifth state parameter, where the fifth state parameter is used to indicate a COUNT value corresponding to a first data packet that has not been submitted by the Packet Data Convergence Protocol (PDCP) layer of the receiving end to an upper layer of the PDCP layer; A sixth state parameter, wherein the sixth state parameter is used to indicate a COUNT value corresponding to a data packet that triggers a reassembly timer of the PDCP layer.

29. The method according to claim 28, characterized in that The discarded data packets update the transmission state parameters of the receiving end, including: If the discarded data packet meets a fourth condition, updating the transmission state parameter of the receiving end based on the discarded data packet; wherein the fourth condition includes: The COUNT value corresponding to the discarded data packet is between the COUNT value indicated by the fifth status parameter and the COUNT value corresponding to the next data packet received by the PDCP layer; Or the COUNT value corresponding to the discarded data packets is greater than or equal to the COUNT value indicated by the fifth state parameter; Or the COUNT value corresponding to the discarded data packet is less than or equal to the COUNT value corresponding to the next data packet received by the PDCP layer.

30. The method according to claim 28, wherein The updating of the transmission state parameter of the receiving end based on the discarded data packet includes: If there is a sixth data packet whose COUNT value is the same as the COUNT value indicated by the fifth status parameter among the discarded data packets, updating the fifth status parameter to a second COUNT value following the first COUNT value of the sixth data packet; Alternatively, corresponding to the absence of a data packet with a COUNT value identical to the COUNT value indicated by the fifth state parameter among the discarded data packets, when the fifth state parameter is updated to the first COUNT value, the fifth state parameter is updated to the second COUNT value.

31. The method according to claim 29, wherein The updating of the transmission state parameter of the receiving end based on the discarded data packet includes: If the COUNT value indicated by the fifth status parameter is the same as the first COUNT value of the sixth data packet among the discarded data packets, updating the fifth status parameter to a second COUNT value subsequent to the first COUNT value, wherein the sixth data packet is the data packet with the smallest COUNT value among the discarded data packets; Alternatively, the COUNT value indicated by the fifth status parameter is different from the first COUNT value. When the fifth status parameter is updated to the first COUNT value, the fifth status parameter is updated to the second COUNT value.

32. The method according to claim 30 or 31, characterized in that The discarded data packets include a third consecutive data packet, the third consecutive data packet includes the sixth data packet, and the second COUNT value is a COUNT value of a seventh data packet after the third consecutive data packet.

33. The method according to claim 32, characterized in that The seventh data packet is the next data packet of the third consecutive data packet, or the first data packet after the third consecutive data packet that is not submitted to the upper layer of the PDCP layer, or the first data packet after the third consecutive data packet that is not submitted to the upper layer of the PDCP layer and is not among the discarded data packets.

34. The method according to claim 30 or 31, characterized in that The updating of the transmission state parameter of the receiving end based on the discarded data packet further includes: When the second COUNT value is greater than the COUNT value indicated by the sixth status parameter, the sixth status parameter is updated to the COUNT value corresponding to the next data packet received by the PDCP layer. And / or start the reassembly timer of the PDCP layer.

35. The method according to claim 32, wherein The first COUNT value and the third COUNT value corresponding to the last data packet in the third consecutive data packets are maintained based on the fifth discard state parameter and the sixth discard state parameter, respectively.

36. The method according to claim 35, characterized in that The method further comprises: Determine at least one consecutive data packet to be discarded, where a maximum value of COUNT values corresponding to the at least one consecutive data packet is a fourth COUNT value, a minimum value is a fifth COUNT value, and the fourth COUNT value is greater than or equal to the fifth COUNT value; corresponding to the fourth COUNT value being less than the fifth discarding state parameter, updating the fifth discarding state parameter to the fifth COUNT value and updating the sixth discarding state parameter to the fourth COUNT value; or corresponding to the fourth COUNT value being greater than the fifth discard state parameter, and the fifth COUNT value being greater than or equal to the fifth discard state parameter and less than or equal to the sixth discard state parameter, updating the sixth discard state parameter to the fourth COUNT value; or corresponding to the fourth COUNT value being less than or equal to the sixth discard state parameter and greater than or equal to the fifth state parameter, and the fifth COUNT value being less than the fifth discard state parameter, updating the fifth discard state parameter to the fifth COUNT value; or corresponding to the fourth COUNT value being less than or equal to the sixth discard state parameter and greater than or equal to the fifth state parameter, and the fifth COUNT value being less than the fifth discard state parameter, updating the fifth discard state parameter to the fifth COUNT value; Alternatively, corresponding to the fourth COUNT value and the fifth COUNT value being between the fifth discard state parameter and the sixth discard state parameter, or the fifth COUNT value being greater than the sixth discard state parameter, the fifth discard state parameter and the sixth discard state parameter are not updated.

37. The method according to claim 28, wherein By the PDCP layer: Identify dropped packets; The transmission state parameters of the receiving end are updated based on the discarded data packets.

38. The method according to claim 14, wherein The step of determining the discarded data packets includes: Drop information indicating the dropped data packet is received.

39. A transmitting end device, characterized in that: include: one or more processors; one or more memories; The one or more memories store one or more computer programs, and the one or more computer programs include instructions. When the instructions are executed by the one or more processors, the sending device implements the method described in any one of claims 1 to 13.

40. A receiving device, characterized in that: include: one or more processors; one or more memories; The one or more memories store one or more computer programs, and the one or more computer programs include instructions. When the instructions are executed by the one or more processors, the receiving device implements the method described in any one of claims 14 to 38.

41. A communication system, characterized in that The communication system comprises: The transmitting device according to claim 39 and the receiving device according to claim 40.

42. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable program instructions, which, when executed on a computer, enable the computer to implement the method of any one of claims 1 to 13 or any one of claims 14 to 38.

43. A computer program product, comprising computer program code, which, when run on a computer, causes the computer to implement the method of any one of claims 1 to 13, or the method of any one of claims 14 to 38.