CN114499749B

CN114499749B - Data transmission method and related equipment thereof

Info

Publication number: CN114499749B
Application number: CN202011270069.8A
Authority: CN
Inventors: 施玲玲
Original assignee: Shanghai Huawei Technologies Co Ltd
Current assignee: Shanghai Huawei Technologies Co Ltd
Priority date: 2020-11-13
Filing date: 2020-11-13
Publication date: 2024-06-11
Anticipated expiration: 2040-11-13
Also published as: WO2022100733A1; CN114499749A

Abstract

The embodiment of the application discloses a data transmission method and related equipment, which are used in the technical field of communication. The method comprises the following steps: the PDCP layer of the packet data aggregation protocol of the transmitting end determines the number N of the first data packets in the data packets to be transmitted according to the length of a receiving window corresponding to the receiving end; the generation transmission data packet sequence comprises M generation transmission data packets, wherein M is greater than the length of the receiving window, and N is less than the length of the receiving window; the sending end numbers the serial number SN of the first data packet; the transmitting end determines the remaining generation of transmitting data packets as second data packets; the second data packet does not carry an SN; the sending end sequentially sends the first data packet and the second data packet to the target end, so that the target end forwards the first data packet and the second data packet to the receiving end.

Description

Data transmission method and related equipment thereof

Technical Field

The embodiment of the application relates to the technical field of communication, in particular to a data transmission method and related equipment thereof.

Background

In a long term evolution (long term evolution, LTE) system, a packet data convergence protocol (PACKET DATA convergence protocol, PDCP) layer may allocate a 32-bit number (count) to data for integrity protection and encryption and decryption; wherein, the count is composed of an upper super frequency number (HYPER FRAME number, HFN) and a lower Sequence Number (SN); the SN is fixed in length, and may occupy 5 bits, 12 bits, or 16 bits, as configured by the upper layer.

In the process of the mutual communication between the sending end and the receiving end, the sending end and the receiving end respectively store HFNs, then the sending end sequentially numbers the data packets to determine the SN corresponding to each data packet, then the self-stored HFNs and the SNs corresponding to each data packet are utilized to form a count value corresponding to each data packet, finally the data packets are encrypted according to the count value corresponding to each data packet and other parameters and then sent to the receiving end, namely the sending end continuously increases 1 in the data transmission process; when the SN reaches a maximum value, the transmitting end will invert, so that the HEV stored by itself adds 1, and then the subsequent data packets are numbered from the initial transition state.

Because the data packet sent by the sending end only carries SN and does not carry HFN, the receiving end updates the stored HFN according to the SN number carried by the data packet, specifically, the receiving end uses the SN of the received data packet as the lower limit value of the receiving window, then the lower limit value updates the receiving window, and receives the data packet according to the receiving window, after the lower limit value of the receiving window is turned over, the stored HFN is added with 1, and then decrypts the received data packet according to the stored HFN and the SN of the data packet.

Under the condition of poor switching data or channel quality, a large amount of packet loss occurs, so that a data packet received by a receiving end cannot fall into a receiving window, the receiving window cannot be updated, and thus, HFN stored by the receiving end and HFN of a transmitting end cannot be synchronously updated, and thus, the data packet received by the transmitting end subsequently cannot be decrypted correctly, and the flow is interrupted and cannot be recovered.

Disclosure of Invention

The embodiment of the application provides a data transmission method and related equipment, which are used for numbering and transmitting SN numbers of data packets to be transmitted by a PDCP layer, so that the situation of flow interruption caused by different HFNs of super frame numbers stored by a transmitting end and a receiving end is avoided.

A first aspect of an embodiment of the present application provides a data transmission method, including:

When the transmitting end and the receiving end perform data transmission, if the number of data packets to be transmitted by the transmitting end exceeds the length of a receiving window of the receiving end, the PDCP layer of the transmitting end can firstly determine the number of first data packets which need to carry SN numbers in the data packets to be transmitted according to the length of the receiving window of the receiving end, and then sequentially numbering the SNs of the first data packets; and then determining the rest data packets as second data packets without SN, finally sequentially sending the first data packets and the second data packets to the target end, and then forwarding the received data packets to the receiving end by the target end.

In the scene of flow switching, a large number of packet losses often occur between a sending end and a target end (a forwarding side), if the number of packet losses exceeds the length of a receiving window of a receiving end, the receiving window is not slid, HFN cannot be normally maintained, and finally HFN asynchronization of the sending end and the receiving end occurs, so that the receiving end cannot normally decrypt received data packets; in this embodiment, when the transmitting end transmits the data packet to the target end, it is ensured that the number of the first data packets with SN in the data packet sequence does not exceed the length of the receiving window of the receiving end, so that even if the first data packets with SN are lost in the transmission process, the data packets fall into the receiving window, the receiving window will slide normally, the receiving end will maintain HFN normally, and the phenomenon that HFN maintained by the receiving end and the transmitting end are not aligned is avoided.

In an optional implementation manner, when the sending end sequentially sends the first data packet and the second data packet to the target end, the sending end also needs to send the self-numbering condition to the target end, namely send indication information to the target end to tell the starting point of the numbering of the target end; in this way, the target end can continue numbering the second data packet which is received and does not carry the SN according to the starting point, namely, the data packet finally received by the receiving end carries the SN, and the receiving end maintains the HFN stored by itself according to the SN carried by the data packet.

In this embodiment, the sender indicates the starting point of SN numbering of the target, and the target can sequentially number the second data packets successfully received according to the starting point, so that even if a large number of packet losses occur between the sender and the target, the target still can number the received data packets which do not carry SN from the starting point, thus ensuring that SN of the data packets forwarded to the receiver always falls into the receiving window, ensuring normal sliding of the receiving window and ensuring normal updating of the HFN of the receiving end.

In an alternative embodiment, when the data packet sent by the sending end exceeds an SN length, the sending end adds 1 to the stored hyper frame number HFN, and then starts from the initial state, and performs SN numbering on the data packet again for the second round; it will be appreciated that in the second round of numbering, it is also ensured that the number of packets carrying SNs does not exceed the length of the receiving window.

In an alternative embodiment, the occurrence of the asynchronous phenomenon caused by the HFN maintained by the sending end and the receiving end respectively is caused by a large number of packet losses of the sending end and the target end during data transmission, so that the sending end can count all data packets sent by itself, the target end counts the number of data packets successfully received by itself, then compares the counted number of data packets to estimate the number of lost packets, if the number of lost packets exceeds the length of a receiving window, the abnormal packet sending can be determined, and then the processing can be performed according to the abnormal packet sending phenomenon, including retransmission of the data packets, or re-access of released link resources, etc.

Therefore, the transmitting end can determine the total number of the transmitted data packets, and then transmit the total number of the transmitted data packets to the target end for the target end to judge the packet loss condition.

In an alternative embodiment, the sending end may also determine the packet loss condition; the target end sends feedback information to the sending end, wherein the feedback information is used for reporting the total number of the data packets successfully received by the target end; and the sending end counts the number of all data packets sent by the sending end, compares the number of the data packets with the number of the data packets to obtain the number of lost packets, finally judges whether the number of lost packets reaches a preset threshold, if the number of lost packets reaches the length of a receiving window, the sending end determines that the sending of the data packets is abnormal, and the sending end can perform final processing according to the abnormal phenomenon of the sending of the data packets.

A second aspect of an embodiment of the present application provides another data transmission method, including:

The target end receives the data packet sent by the sending end and then forwards the sending packet to the receiving end; firstly, a data packet sent by a sending end to a target end comprises a first data packet carrying SN and a second data packet not carrying SN, after the target end receives the second data packet not carrying SN, the SN number of the first data packet is needed to be continued to number the SN of the second data packet, and then the first data packet and the numbered second data packet are sequentially forwarded to a receiving end according to the SN.

In this embodiment, the target end sequentially numbers the second data packets which are successfully received, so that even if a large number of packet loss occurs between the transmitting end and the target end, the target end still starts numbering the received data packets which do not carry SN, so that SN of the data packets forwarded to the receiving end is guaranteed to always fall into the receiving window, normal sliding of the receiving window is guaranteed, normal updating of the HFN of the receiving end is guaranteed, and the phenomenon that HFN maintained by the receiving end and the transmitting end are not aligned is avoided.

Therefore, the target end needs to receive the total number of the sent data packets sent by the sending end, and then the target end determines the total number of the data packets which are successfully received by the target end; and finally, estimating the number of the lost packets to determine the packet loss condition.

A third aspect of the present application provides a transmitting apparatus comprising:

the determining unit is used for determining the number N of the first data packets in the data packets to be transmitted according to the length of the receiving window corresponding to the receiving end; the generation transmission data packet sequence comprises M generation transmission data packets, wherein M is greater than the length of the receiving window, and N is less than the length of the receiving window;

a processing unit, configured to number a sequence number SN of the first data packet;

The determining unit is further configured to determine that the remaining generation of transmission data packet is a second data packet; the second data packet does not carry an SN;

And the sending unit is used for sequentially sending the first data packet and the second data packet to the target end so that the target end forwards the first data packet and the second data packet to the receiving end.

In an optional implementation manner, the sending unit is further configured to send indication information to the target end; the indication information comprises a number upper limit value of the sending end; the indication information is used for indicating the target end to number the received SN of the second data packet.

In an optional implementation manner, the processing unit is further configured to update the stored hyper frame number HFN when the number of the transmitted data packets exceeds the SN length;

the determining unit is further used for determining the number N of the first data packets in the data packets sent instead of the first data packets again from the initial state;

The processing unit is further configured to number an SN of a first data packet in the sending data packet.

In an optional embodiment, the determining unit is further configured to determine a total number of sent data packets, and send the total number of sent data packets to the target end.

In an alternative embodiment, the transmitting device further comprises a receiving unit:

the receiving unit is used for receiving feedback information sent by the target end, wherein the feedback information comprises the total number of data packets successfully received by the target end;

The determining unit is further configured to determine whether the number of lost packets reaches a preset threshold according to the feedback information; if the preset threshold is reached, determining that the PDCP layer determines that the packet is abnormal.

A fourth aspect of the present application provides a forwarding device comprising:

the receiving unit is used for receiving the first data packet and the second data packet sent by the sending end; the first data packet carries a serial number SN, the second data packet does not carry the SN, and the number N of the first data packet is smaller than the length of a receiving window corresponding to a receiving end;

a processing unit, configured to number an SN of the second data packet;

and the sending unit is used for sequentially sending the first data packet and the numbered second data packet to the receiving end.

In an optional implementation manner, the receiving unit is further configured to receive the indication information sent by the sending end; the indication information comprises a number upper limit value of the sending end;

the processing unit is specifically configured to sequentially number the SN numbers of the second data packets according to the number upper limit value.

In an alternative embodiment, the forwarding device further comprises a determining unit;

The receiving unit is further configured to receive the total number of transmitted data packets sent by the transmitting end;

The determining unit is used for determining the total number of the data packets which are successfully received by the determining unit; determining a packet loss condition according to the total number of the sent data packets and the total number of the data packets which are received successfully by the self;

the sending unit is further configured to send feedback information to the sending end, where the feedback information is used to report the packet loss situation to the sending end.

the determining unit is used for determining the total number of the data packets which are successfully received by the determining unit;

The sending unit is further configured to send the total number of the data packets that are received successfully to the sending end.

A fifth aspect of the present application provides a transmitting apparatus comprising: at least one processor and a memory storing computer-executable instructions executable on the processor, the transmitting device performing the method as described above in the first aspect or any one of the possible implementations of the first aspect when the computer-executable instructions are executed by the processor.

A sixth aspect of the present application provides a forwarding apparatus, including: at least one processor and a memory storing computer-executable instructions executable on the processor, the forwarding device performing the method according to the second aspect or any one of the possible implementations of the second aspect as described above when the computer-executable instructions are executed by the processor.

A seventh aspect of the present application provides a chip or chip system comprising at least one processor and a communication interface, the communication interface and the at least one processor being interconnected by wires, the at least one processor being for running a computer program or instructions to perform a data transmission method as described in any one of the possible implementations of the first aspect;

the communication interface in the chip can be an input/output interface, a pin, a circuit or the like.

In one possible implementation, the chip or chip system described above further includes at least one memory, where the at least one memory has instructions stored therein. The memory may be a memory unit within the chip, such as a register, a cache, etc., or may be a memory unit of the chip (e.g., a read-only memory, a random access memory, etc.).

An eighth aspect of the present application provides a chip or chip system comprising at least one processor and a communication interface, the communication interface and the at least one processor being interconnected by wires, the at least one processor being adapted to run a computer program or instructions for performing a data transmission method as described in any one of the possible implementations of the second aspect to the second aspect;

A ninth aspect of an embodiment of the present application provides a computer-readable storage medium having stored therein a computer program which, when run on a computer, causes the computer to execute the data transmission method of any one of the first to second aspects described above.

From the above technical solutions, the embodiment of the present application has the following advantages:

When the transmitting end and the receiving end perform data transmission, the PDCP layer of the transmitting end firstly determines the number of first data packets which need to carry SN numbers in the data packets to be transmitted according to the length of a receiving window received by the receiving end, and then sequentially numbering the SNs of the first data packets; then determining the rest data packets as second data packets without SN, finally sequentially sending the first data packets and the second data packets to the target end, and then forwarding the received data packets to the receiving end by the target end; when the transmitting end transmits the data packet to the target end, the number of the first data packets with the SN in the data packet sequence is ensured not to exceed the length of a receiving window of the receiving end, so that even if the first data packets with the SN are lost in the transmission process, the data packets fall into the receiving window, the receiving window can slide normally, the receiving end can maintain the HFN normally, and the phenomenon that the HFNs maintained by the receiving end and the transmitting end are not aligned is avoided.

Drawings

Fig. 1 is a schematic flow chart of a data transmission method according to an embodiment of the present application;

fig. 2 is a schematic structural diagram of a transmitting device according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of a forwarding device according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of another transmitting device according to an embodiment of the present application;

Fig. 5 is a schematic structural diagram of another forwarding device according to an embodiment of the present application.

Detailed Description

The following detailed description of the present application refers to the accompanying drawings, which illustrate only some, but not all, embodiments of the application.

The terms "first," "second," "third," "fourth" and the like in the description and in the claims and in the above drawings, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments described herein may be implemented in other sequences than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

A long term evolution (long term evolution, LTE) wireless communication system is a high-speed wireless communication system established on a third generation mobile communication system. In the LTE air interface user plane protocol stack, a PDCP protocol layer, a radio link control (radio link control, RLC) layer, a medium access control (medium access control, MAC) layer and a physical layer are sequentially arranged from top to bottom; wherein each layer completes different data processing, the PDCP layer mainly performs security operation and header compression and decompression processing, such as confidentiality, integrity protection and the like; the RLC layer mainly completes segment concatenation of data, sequential delivery, automatic retransmission request (automatic repeat request, ARQ) data transmission guarantee, etc.; the MAC layer mainly completes scheduling, cascading processing among different logic channels, hybrid automatic repeat request (hybrid automatic repeat request, HARQ) operation and the like; and finally, the physical layer completes the transmission block contracture and the air interface transmission.

In the data transmission process, a transmitting end (base station) PDCP layer interacts with an RLC layer of a lower layer; the PDCP layer manages Sequence Numbers (SNs) for service data units (service dataunits, SDUs) received from a higher layer, then performs header compression, integrity protection and ciphering, updates state variables, generates protocol data units (protocol data unit, PDUs), and finally transmits the PDUs to the RLC layer; after the RLC layer receives the PDU, the PDU is sent in sequence according to the sequence number carried by the PDU, and finally the PDU is sent to a receiving end (terminal); in response mode, the RLC layer returns a successful acknowledgement message of PDCP PDU to the PDCP layer; the PDCP layer clears the PDCP PDUs from the transmit buffer after receiving the acknowledgement message.

The PDCP layer allocates a 32-bit number count to each data Packet (PDU), wherein the count is composed of a high HFN and a low SN; the length of the SN is configured by an upper layer, which may be 5bit, 7bit, 12bit, or the like, and is not limited in particular, before sending a data packet, the PDCP layer sequentially configures corresponding SNs for the data packet in the buffer sequence, and, for example, may be numbered from 0 to determine the SN corresponding to each data packet; the high-order HFN is maintained uniformly by the transmitting end, for example, it is determined that HFNs of a plurality of data packets to be forwarded currently are all 1; thus, each data packet may be composed of HFN and SN corresponding thereto to form a different count, and the PDCP layer finally encrypts the data packet according to the count corresponding to each data packet, and transmits the encrypted data packet to the receiving end.

It can be understood that the SN length will limit the upper limit value of the number, for example, the SN length configured by the upper layer is 12 bits, and then the space size of the SN is 2 ¹² =4096, that is, the PDCP layer can be configured for SN numbers of 4096 data packets at most, that is, the SN number corresponding to the first data packet is determined to be 0, until the SN number of 4096 data packets is 4097; when the number of packets to be sent of the PDCP layer exceeds 4096, the HFN maintained by the sender needs to be updated, and illustratively, hfn+1 may be then renumbered from 0 for the 4097 th packet and subsequent packets; that is, in the process of continuously transmitting data packets, SN is continuously increased by 1, after SN corresponding to a certain data packet which is successfully transmitted reaches a maximum value, HFN corresponding to the transmitting end is increased by 1, and SN corresponding to a data packet to be transmitted thereafter is turned over. Thus, the count value of each data packet sent by the sending end is different.

In the data packet sent from the sending end to the receiving end, only the SN corresponding to the data packet is carried, but the current HFN of the sending end is not carried, and generally, the sending end and the receiving end respectively maintain the corresponding HFNs; the receiving end corresponds to a receiving window, which receives only the data packet having SN falling into the receiving window, specifically, the length of the receiving window is generally equal to the SN space size, and in the above example, the SN space size of the upper layer configuration is 2 ¹² =4096 if the SN space size is 12 bits, the receiving window is half of the size 2048, the lower limit value of the receiving window determines the position of the receiving window, for example, the lower limit value of the receiving window is 10, the receiving window receives the data packet having SN of 10 to 2057, and the data packet falling outside the receiving window is not received.

The lower limit value of the receiving window is dynamically changed and is determined by the SN of the latest successfully received data packet, for example, the receiving end sequentially receives the data packets, when the SN of the successfully received first data packet is 0, the lower limit value of the receiving window is determined to be 0, and the data packets with the SNs of 0 to 2027 fall into the receiving window and can be received by the transmitting end; then, when the SN of the second packet received by the receiving end is 1, the lower limit value of the receiving window is updated to 1, and at the same time, the packets with SN of 1 to 2048 fall into the receiving window, and similarly, the receiving window slides along with the SN of the successfully received packet to sequentially complete the reception of the plurality of packets, and when the lower limit value of the receiving window is overturned, the receiving end updates its own maintained HFN, so that the HFN of the receiving end and the sending end can be ensured to be synchronous, so that the receiving end can obtain the correct count of each packet through the HFN maintained by itself and the SN carried by the packet, and decrypt the packet by using the correct count.

Under the condition of data traffic switching, the transmitting end transmits the data packet to the target end (base station), and the target end forwards the data packet to the receiving end, so that a large amount of packet loss can occur due to the instability of the channel between the base stations, which may cause the HFN maintained by the receiving end and the transmitting end to be different, so that the receiving end cannot normally decrypt the data packet, thereby causing traffic interruption and irrecoverability. For example, at a certain moment, the transmitting end transmits 5000 data packets to the receiving end through the target end, the corresponding SN space size is 4096, the transmitting end sequentially determines SNs of 5098 data packets, the transmitting end starts numbering from 0, HEN corresponding to the first 4096 data packets is 0, and the SNs sequentially range from 0 to 4095; the sender starts from the 4098 th data packet, adds 1 to the maintained HFN, and then starts from 0 to number the 4098 th data packet, namely, the HFN corresponding to the 4098 th to 5098 th data packets is 1, and the SN is 0 to 999. The sender then sends these packets to the destination in turn.

The target end forwards the successfully received data packet, and it can be understood that the initial HFN stored by the receiving end is also 0, and the corresponding window length is 2048, namely the initial receiving window is 0 to 2047; if the target side successfully forwards the data packet with SN of 1 to the receiving end, the receiving window of the receiving end is updated to 1 to 2048, if no packet loss occurs, i.e. the receiving end successfully receives the 4096 th data packet, the receiving end determines the lower limit value of the receiving window to be 4095, updates the receiving window to 4095 to 2046, and when the 4097 th data packet is received again, as the 4097 th data packet corresponds to SN of 0, the receiving end judges that the lower limit value of the window is sent to be overturned, the HFN stored by the receiving end is added with 1, and the HFN of the receiving end and the sending end is kept consistent.

However, in the case that a large number of packet losses occur, the packets received by the receiving end will not be continuous packets, in the above example, if the receiving window of the receiving end is updated to 1 to 2048 and all the packets with SN of 2 to 2048 are lost, after the receiving end successfully receives the packets with SN of 1, the SN number of the packets received again does not fall into the receiving window, the receiving window will discard the received packets, and the original receiving window and HFN are maintained unchanged, i.e. the receiving end window is 1 to 2048 and HFN is 0; after that, when the receiving end receives the 4097 th to 5098 th data packets again, the receiving end will receive the data packets because the SN numbers corresponding to the data packets are 0 to 999 and successfully fall into the receiving window, but the receiving end still considers the HFN to be 0 because the receiving end does not perceive the overturn of the lower limit value of the receiving window, and in fact, the HFN corresponding to the 4097 th to 5098 th data packets is already 1, which leads to inconsistent HFNs of the transmitting end and the receiving end, and the receiving end cannot decrypt the received data packets, resulting in flow interruption.

Based on the above-mentioned problems, the embodiment of the present application provides a data transmission method and related device, when determining an SN corresponding to a data packet, a PDCP layer at a transmitting end may only number a part of SNs of the data packet, then a part of the data packet carries the SN and transmits to a target side, and a part of the data packet does not carry the SN and transmits to the target side, then the target side, after receiving the data packet which does not carry the SN, numbers the SN and then transmits, and finally, all the data packets received by a receiving end carry the SN.

Fig. 1 is a schematic flow chart of a data transmission method according to an embodiment of the present application; as shown in fig. 1, the data transmission method includes the steps of:

101. the sending end determines the number N of the first data packets carrying the SN according to the length of the receiving window;

In the flow switching process, a sending end sends a data packet to a target end, and the target end forwards the data packet for a receiving end; before sending data packets, a sending end firstly determines the number N of first data packets carrying SN, then selects N data packets in a data packet sequence to be sent as the first data packets, and determines the rest data packets as second data packets; wherein the number of the first data packets is smaller than the length of the receiving window (PDCP reordering window).

For example, the SN length of the upper layer configuration is 12 bits, i.e. the SN space size is 2 ¹² =4096; in general, the receiving window corresponding to the receiving end occupies half of the size of the SN space; i.e. the length of the receiving window is 2048, the number of the first data packets determined by the transmitting end cannot exceed 2047, for example, the transmitting end needs to transmit 3000 data packets, so that the first 2047 data packets in the sequence of data packets to be transmitted can be selected as the first data packets, and the second data packets which do not carry SN can be determined from the 2048 th data packet to the 3000 th data packet.

It can be appreciated that in the PDCP data forwarding process, PDCP data forwarding includes PDCP data forwarding in a handover scenario, PDCP data forwarding in an NSA scenario, and so on; the method is not only applicable to the traffic switching scene under the LTE system, but also applicable to the traffic switching scene under the NR system, and also applicable to the traffic switching scene between the LTE system and the NR system, and is not particularly limited.

102. The transmitting end numbers the SNs of the N first data packets in sequence;

After the transmitting end determines the first data packet, the SN of the first data packet may be sequentially numbered, for example, in the above example, the transmitting end determines that the SNs of the 1 st to 2047 th data packets are sequentially 0 to 2046.

103. The sending terminal sends a first data packet and a second data packet to the target terminal;

The sending end sends the first data packet and the second data packet to the target end, and then the target end sends the received data packet to the receiving end, and it can be understood that the first data packet sent by the sending end to the target end carries SN, and the second data packet does not carry SN.

It can be understood that when the number of the first data packet and the second data packet sent exceeds 4096, the HFN of the sending end needs to be increased by 1, and then the subsequent data packets are numbered continuously from 0.

104. The sending terminal sends indication information to the target terminal;

The sending end also needs to send indication information to the target end, where the indication information is used to instruct the target end to number the second data packet that does not carry SN first, and forward the second data packet to the receiving end after the second data packet carries SN again.

The receiving end can receive the data packets in sequence according to the SNs carried by the data packets, and can judge the packet loss condition according to the SNs, so that the target end is required to number the second data packets which do not carry the SNs and then forward the second data packets.

The indication information includes a numbering condition of the sending end, for example, an upper limit value of a number corresponding to the sending end is sent to the target end, and the target end is indicated to number the received second data packet next to the upper limit value; for example, in the above example, the sending end determines that the number of the first data packets is 2047, then the sending end may determine the 1 st to 2047 th data packets of the sequence to be sent as the first data packets and determine that the corresponding SNs are 0 to 2046, then the sending end may determine that the upper limit value of the number is 2047, that is, the corresponding SN of the next packet, and the sending end sends the count value of the next packet to the destination end with the indication information, so as to indicate that the destination end receives the second data packet without SN, and numbering is performed from 2047.

105. The target end numbers the SN corresponding to the second data packet according to the indication information sent by the sending end;

The target end numbers the second data packet, and then forwards the first data packet and the numbered second data packet to the target end in sequence, and it can be understood that the data transmission between the transmitting end and the target end may possibly send a large number of packets to be lost, if each data sent by the transmitting end carries SN, a large number of data packets carrying SN will be lost, when the number of lost packets exceeds the length of the receiving window, the data packets received by the receiving end will fall outside the receiving window and cannot slide normally, and finally HFN of the transmitting end and the receiving end are different; when the target end numbers the second data packet, the target end only numbers the received second data packet, no matter how many packets are lost, the target end only numbers the second data packet which is successfully received, and then forwards the first data packet and the second data packet to the receiving end, so that the first second data packet sent by the target end falls in a receiving window, the receiving window is updated, then HFN is normally maintained according to the lower limit value of the receiving window, finally, the HFN synchronization of the sending end and the receiving end is ensured, and flow interruption is avoided.

For example, the SN length of the upper layer configuration is 12 bits, that is, the space size of the SN is 2 ¹² =4096, the length of the receiving window is 2048, and the receiving end needs to send 5000 data packets to the sending end; the receiving end firstly determines the number of the first data packets so that the number of the first data packets does not exceed 2048, for example, the number of the first data packets is 2000; in this way, the transmitting end determines the SN of the first 2000 data packets in the transmission sequence, the serial numbers are 0 to 1999 in sequence, and determines that the last 3000 data packets do not carry SN for transmission; the destination is then instructed to number data packets that do not carry SN from 2000.

It can be understood that, even if a large number of packet losses occur between the transmitting end and the destination end, for example, a packet is lost from the third data packet, and 2048 data packets are lost altogether, when the 2051 st data packet is successfully received by the destination end, the destination end still numbers from 2001 according to the instruction of the transmitting end, that is, the 2051 st second data packet without SN is numbered 2001, so that the second data packet falls into the receiving window of the receiving end, the receiving end normally receives the second data packet, and updates the position of the receiving window according to the SN; when the receiving end receives the first data packet again, that is, when the SN of the received data packet does not exceed 1999, the lower limit value of the receiving window can be determined to be overturned, and the maintained HFN is added with 1, so that the HFN of the sending end and the HFN of the receiving end are consistent, the receiving end can successfully decrypt the received data packet, and flow interruption is avoided.

106. The target end forwards the first data packet and the numbered second data packet to the receiving end;

107. The transmitting end determines the total number of the transmitted data packets;

It can be understood that when a large number of packet losses occur between the sending end and the target end, transmission abnormality is caused, even the flow is interrupted and cannot be recovered, so that the sending end can determine the total number of data packets to be sent before sending the data packets, then determine whether a large number of packet losses occur according to the number of data packets successfully received by the target end, and then take relevant measures for the large number of packet losses.

108. The sending terminal sends request information to the target terminal;

In a specific embodiment, the sending end sends request information to the target end, where the request information is used to instruct the target end to report the total number of data packets that are counted and successfully received, and then the sending end performs whether a large number of packet losses occur.

109. The target end determines the total number of data packets successfully received according to the request information;

110. the target end reports the total number of the data packets successfully received to the sending end;

And the target end reports the total number of the data packets successfully received to the sending end according to the indication information.

111. The sending terminal determines the packet loss condition according to the total number of successfully received data packets reported by the target terminal;

after the transmitting end obtains the total number of the data packets which are transmitted by the target end and are successfully received, the number of the lost packets is determined, and the total number of the data packets which are successfully received is subtracted from the total number of the data packets which are transmitted to obtain the number of the lost packets, then whether the number of the lost packets reaches a preset threshold value is judged, and then corresponding ear processing is carried out according to a judging result.

112. The transmitting terminal transmits the total number of the transmitted data packets to the target terminal;

The transmitting end may also transmit the total number of the transmitted data packets to the target end, where the target end determines the packet loss on the link.

113. The target end determines the packet loss condition according to the total number of the sent data packets and the total number of the data packets which are successfully received;

the target end uses the total number of the data packets which are sent by the sending end and are sent by the receiving end to subtract the total number of the data packets which are successfully received, and the packet loss condition is determined.

114. The target end reports the packet loss condition to the transmitting end;

It will be appreciated that steps 108 to 111 and steps 112 to 114 are optional steps, and that steps 109, 110 and 111 need to be performed when step 108 is performed; when step 112 is performed, steps 113 and 114 are performed.

115. The transmitting end determines whether abnormal phenomenon of packet sending occurs according to the packet loss condition;

The sending end performs corresponding processing according to the packet loss condition, for example, the preset threshold value may be the number corresponding to the receiving window, and when the packet loss number exceeds the length of the receiving window, the retransmission may be reset or the receiving end may be released.

Fig. 2 is a schematic structural diagram of a transmitting device according to the present application, as shown in fig. 2, where the transmitting device includes:

A determining unit 201, configured to determine, according to a length of a receiving window corresponding to a receiving end, a number N of first data packets in the data packets to be sent; the generation transmission data packet sequence comprises M generation transmission data packets, wherein M is greater than the length of the receiving window, and N is less than the length of the receiving window;

A processing unit 202, configured to number a sequence number SN of the first data packet;

the determining unit 201 is further configured to determine that the remaining generation of transmission data packet is a second data packet; the second data packet does not carry an SN;

And the sending unit 203 is configured to send the first data packet and the second data packet to a target end in sequence, so that the target end forwards the first data packet and the second data packet to the receiving end.

The sending unit 203 is configured to send indication information to the target end; the indication information comprises a number upper limit value of the sending end; the indication information is used for indicating the target end to number the received SN of the second data packet.

Illustratively, the processing unit 202 is further configured to update the stored hyper frame number HFN when the number of transmitted data packets exceeds the SN length;

the determining unit 201 is further configured to, starting from the initial state, redetermine the number N of the first packets in the transmission data packets;

the processing unit 202 is further configured to number an SN of a first packet of the proxy transmission packets.

Illustratively, the determining unit 201 is further configured to determine the total number of sent data packets, and send the total number of sent data packets to the target end.

Illustratively, the transmitting device further includes a receiving unit 204:

The receiving unit 204 is configured to receive feedback information sent by the target, where the feedback information includes a total number of data packets successfully received by the target;

the determining unit 201 is further configured to determine whether the number of dropped packets reaches a preset threshold according to the feedback information; if the preset threshold is reached, determining that the PDCP layer determines that the packet is abnormal.

Fig. 3 is a schematic structural diagram of a forwarding device provided by the present application, as shown in fig. 3, where the forwarding device includes:

A receiving unit 301, configured to receive a first data packet and a second data packet sent by a sending end; the first data packet carries a serial number SN, the second data packet does not carry the SN, and the number N of the first data packet is smaller than the length of a receiving window corresponding to a receiving end;

a processing unit 302, configured to number an SN of the second data packet;

And the sending unit 303 is configured to send the first data packet and the numbered second data packet to the receiving end sequentially.

The receiving unit 301 is configured to receive indication information sent by the sending end; the indication information comprises a number upper limit value of the sending end;

the processing unit 302 is specifically configured to sequentially number SN numbers of the second data packets according to the number upper limit value.

Illustratively, the forwarding device further includes a determining unit 304;

the receiving unit 301 is further configured to receive a total number of transmitted data packets sent by the sending end;

The determining unit 304 is configured to determine a total number of data packets that are received successfully by itself; determining a packet loss condition according to the total number of the sent data packets and the total number of the data packets which are received successfully by the self;

the sending unit 303 is further configured to send feedback information to the sending end, where the feedback information is used to report the packet loss situation to the sending end.

Illustratively, the forwarding device further includes a determining unit 304;

the determining unit 304 is configured to determine a total number of data packets that are received successfully by itself;

the sending unit 303 is further configured to send the total number of data packets that are received successfully by itself to the sending end.

Referring to fig. 4, a schematic structural diagram of another transmitting apparatus 400 according to an embodiment of the present application is provided, where the transmitting apparatus 400 includes: processor 401, memory 402, and communication interface 403.

The processor 401, the memory 402, the communication interface 403 are connected to each other by a bus; the bus may be a peripheral component interconnect standard (PERIPHERAL COMPONENT INTERCONNECT, PCI) bus, or an extended industry standard architecture (extended industry standard architecture, EISA) bus, among others. The buses may be classified as address buses, data buses, control buses, etc. For ease of illustration, only one thick line is shown in fig. 4, but not only one bus or one type of bus.

The memory 402 may include volatile memory (RAM), such as random-access memory (RAM); the memory may also include a non-volatile memory (non-volatile memory), such as a flash memory (flash memory), a hard disk (HARD DISK DRIVE, HDD) or a solid state disk (solid-state drive (SSD); memory 402 may also include a combination of the above types of memory.

The processor 401 may be a central processor (central processing unit, CPU), a network processor (English: network processor, NP) or a combination of CPU and NP. The processor 401 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (programmable logic device, PLD), or a combination thereof. The PLD may be a complex programmable logic device (complex programmable logic device, CPLD), a field-programmable gate array (FPGA) GATE ARRAY, generic array logic (GENERIC ARRAY logic, GAL), or any combination thereof.

The communication interface 403 may be a wired communication interface, such as an ethernet interface, a wireless communication interface, or a combination thereof. The ethernet interface may be an optical interface, an electrical interface, or a combination thereof. The wireless communication interface may be a WLAN interface, a cellular network communication interface, a combination thereof, or the like.

Wherein the processor 401 is arranged to execute a computer program or instructions in the memory 402 for performing the steps performed by the sender in any one of the possible implementations of the embodiment shown in fig. 1.

Referring to fig. 5, a schematic structural diagram of another forwarding device 500 according to an embodiment of the present application is shown, where the forwarding device 500 includes: a processor 501, a memory 502, and a communication interface 503.

The processor 501, the memory 502, and the communication interface 503 are connected to each other by a bus; the bus may be a peripheral component interconnect standard (PERIPHERAL COMPONENT INTERCONNECT, PCI) bus, or an extended industry standard architecture (extended industry standard architecture, EISA) bus, among others. The buses may be classified as address buses, data buses, control buses, etc. For ease of illustration, only one thick line is shown in fig. 5, but not only one bus or one type of bus.

The memory 502 may include volatile memory (RAM), such as random-access memory (RAM); the memory may also include a non-volatile memory (non-volatile memory), such as a flash memory (flash memory), a hard disk (HARD DISK DRIVE, HDD) or a solid state disk (solid-state drive (SSD); memory 502 may also include a combination of the types of memory described above.

The processor 501 may be a central processor (central processing unit, CPU), a network processor (English: network processor, NP) or a combination of CPU and NP. The processor 501 may further comprise a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (programmable logic device, PLD), or a combination thereof. The PLD may be a complex programmable logic device (complex programmable logic device, CPLD), a field-programmable gate array (FPGA) GATE ARRAY, generic array logic (GENERIC ARRAY logic, GAL), or any combination thereof.

The communication interface 503 may be a wired communication interface, such as an ethernet interface, a wireless communication interface, or a combination thereof. The ethernet interface may be an optical interface, an electrical interface, or a combination thereof. The wireless communication interface may be a WLAN interface, a cellular network communication interface, a combination thereof, or the like.

Wherein the processor 501 is configured to execute a computer program or instructions in the memory 502 to perform steps performed by a target in any one of the possible implementations of the embodiment shown in fig. 1.

The embodiment of the application also provides a chip or a chip system, the chip or the chip system comprises at least one processor and a communication interface, the communication interface and the at least one processor are interconnected through a circuit, and the at least one processor is used for running a computer program or instructions to perform a data transmission method described in any one of possible implementation manners of the embodiment shown in fig. 1;

The embodiment of the application also provides a computer storage medium for storing the computer software instructions for the above-mentioned transmission device, which includes a program for executing the program designed for the transmission device.

The embodiment of the application also provides a computer storage medium for storing the computer software instructions for the forwarding device, which includes a program for executing the program designed for the forwarding device.

Embodiments of the present application also provide a computer program product comprising computer software instructions loadable by a processor to implement the above-described flow in relation to a data transmission method.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product.

It will be clear to those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, which are not repeated herein.

In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be embodied essentially or in part or all of the technical solution or in part in the form of a software product stored in a storage medium, including instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a read-only memory (ROM), a random-access memory (RAM, random access memory), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

Claims

1. A method of data transmission, the method comprising:

The PDCP layer of the packet data aggregation protocol of the transmitting end determines the number N of the first data packets in the data packets to be transmitted according to the length of a receiving window corresponding to the receiving end; the data packet sequence to be sent comprises M data packets to be sent, wherein M is greater than the length of the receiving window, and N is less than the length of the receiving window;

The sending end numbers the serial number SN of the first data packet;

the transmitting end determines the rest data packets to be transmitted as second data packets; the second data packet does not carry an SN;

The sending end sequentially sends the first data packet and the second data packet to the target end, so that the target end forwards the first data packet and the second data packet to the receiving end.

2. The method according to claim 1, wherein the method further comprises:

The sending end sends indication information to the target end; the indication information comprises a number upper limit value of the sending end; the indication information is used for indicating the target end to number the received SN of the second data packet.

3. The method according to any one of claims 1 to 2, further comprising:

when the number of the sent data packets exceeds the SN length, the sending end updates the stored hyper frame number HFN;

the sending end starts from an initial state and redetermines the number N of first data packets in the data packets to be sent;

and the sending end numbers the SN of the first data packet in the data packets to be sent.

4. The method according to any one of claims 1 to 2, further comprising:

The sending end determines the total number of the sent data packets and sends the total number of the sent data packets to the target end.

5. The method according to claim 4, wherein the method further comprises:

The sending terminal receives feedback information sent by the target terminal, wherein the feedback information comprises the total number of data packets successfully received by the target terminal;

The sending end judges whether the number of lost packets reaches a preset threshold value according to the feedback information;

if the preset threshold is reached, the PDCP layer of the transmitting end determines that the packet is abnormal.

6. A method of data transmission, the method comprising:

The target terminal receives a first data packet and a second data packet which are sent by the sending terminal; the first data packet carries a serial number SN, the second data packet does not carry the SN, and the number N of the first data packet is smaller than the length of a receiving window corresponding to a receiving end;

the target end numbers the SN of the second data packet;

and the target end sequentially sends the first data packet and the numbered second data packet to the receiving end.

7. The method of claim 6, wherein the method further comprises:

the target end receives the indication information sent by the sending end; the indication information comprises a number upper limit value of the sending end;

and the target end sequentially numbers the SN numbers of the second data packets according to the number upper limit value.

8. The method according to any one of claims 6 to 7, further comprising:

the target end receives the total number of the sent data packets sent by the sending end;

The target end determines the total number of data packets which are successfully received by the target end;

the target end determines the packet loss condition according to the total number of the sent data packets and the total number of the data packets which are received successfully by the target end;

the target end sends feedback information to the sending end, wherein the feedback information is used for reporting the packet loss condition to the sending end.

9. The method according to any one of claims 6 to 7, further comprising:

The target end determines the total number of the data packets which are successfully received by the target end, and sends the total number of the data packets which are successfully received by the target end to the sending end.

10. A transmitting apparatus, characterized in that the transmitting apparatus comprises:

The determining unit is used for determining the number N of the first data packets in the data packets to be transmitted according to the length of the receiving window corresponding to the receiving end; the data packet sequence to be sent comprises M data packets to be sent, wherein M is greater than the length of the receiving window, and N is less than the length of the receiving window;

The determining unit is further configured to determine that the remaining data packets to be sent are second data packets; the second data packet does not carry an SN;

11. The transmission apparatus according to claim 10, wherein the transmission unit is further configured to transmit indication information to the target terminal; the indication information comprises a number upper limit value of the sending equipment; the indication information is used for indicating the target end to number the received SN of the second data packet.

12. The transmitting device according to any one of claims 10 to 11, wherein the processing unit is further configured to update the stored hyper frame number HFN when the number of transmitted data packets exceeds the SN length;

The determining unit is further configured to re-determine, from the initial state, the number N of first data packets in the data packets to be sent;

The processing unit is further configured to number an SN of a first data packet in the data packets to be sent.

13. The transmitting apparatus according to any one of claims 10 to 11, wherein the determining unit is further configured to determine a total number of transmitted data packets, and transmit the total number of transmitted data packets to the target.

14. The transmission apparatus according to claim 13, wherein the transmission apparatus further comprises a reception unit:

15. A forwarding device, the forwarding device comprising:

a processing unit, configured to number an SN of the second data packet;

16. The forwarding device of claim 15 wherein the receiving unit is further configured to receive the indication information sent by the sending end; the indication information comprises a number upper limit value of the sending end;

17. The forwarding device of any of claims 15 to 16, wherein the forwarding device further comprises a determination unit;

18. The forwarding device of any of claims 15 to 16, wherein the forwarding device further comprises a determination unit;

19. A computer readable storage medium storing one or more computer-executable instructions, which when executed by a processor performs the method of any one of claims 1-5 or claims 6-9.