High-performance packet transmission method

Abstract

The invention discloses a high-performance packet transmission method, which comprises the following steps of: designing a physical layer, reducing the size of a processing unit LDU through the physical layer, reserving protocol overhead, and achieving the purpose of quick transmission without waiting for the transmission of a whole TB (Transport Block) block; a protocol layer is designed, the protocol layer is divided into an LDU layer and a UDU layer, the LDU layer is used for defining a 3-byte LDU head Type1 and reducing protocol overhead, the UDU layer is used for defining a 5-byte UDU head Type2, and a load is user data to be transmitted; fragmentation and recombination, including a fragmentation mechanism and a recombination mechanism; the transmission process comprises a sending mode and a receiving mode. According to the method, the physical layer and the protocol layer are combined, and the throughput and time delay requirements are met under the high throughput and small packet multi-scene.

Description

Technical Field

[0001] The present invention relates to the technical field of mobile communications, and in particular to a high-performance small packet transmission method. Background Art

[0002] In the field of mobile communications, especially in the ad-hoc network environment, high throughput and small packet transmission are common requirements. With the rapid development of emerging applications such as the Internet of Things (IoT) and Vehicle-to-Everything (V2X), mobile communication systems are facing unprecedented challenges. These applications usually need to transmit a large number of small data packets, such as sensor data, control instructions, and status updates. Traditional mobile communication systems, such as 4G LTE and 5G NR, although perform well in high throughput and large bandwidth, often have problems of low air interface utilization and high latency when dealing with small packet transmission. In the field of mobile communications, in the transmission scenario with a large number of small packets, it is easy to waste air interface resources. If waiting to send data to improve air interface utilization, there will be a problem of large latency.

[0003] The main challenge of small packet transmission is how to efficiently transmit a large number of small data packets under limited bandwidth and resources, while ensuring low latency and high reliability. Traditional mobile communication systems usually adopt a relatively large transport block (TB), which will lead to waste of air interface resources and increase of transmission latency when transmitting small packets. In addition, the overhead of the protocol layer will also occupy a large amount of bandwidth, further reducing the overall efficiency of the system.

[0004] Existing solutions, such as the TCP / IP protocol stack and traditional MAC layer protocols, although perform well in dealing with large bandwidth and high throughput, have obvious limitations in the small packet transmission scenario. The overhead of the TCP / IP protocol stack is relatively large, especially when transmitting small packets, the protocol header occupies a relatively large proportion, resulting in a decrease in the effective data transmission rate. Traditional MAC layer protocols, such as the MAC layer of LTE, usually need to wait for the transmission and reception of the entire transport block, which will lead to a relatively high transmission latency. Summary of the Invention

[0005] Object of the Invention: In order to solve the above-mentioned problems, the present invention provides a high-performance small packet transmission method for the requirements of air interface utilization and latency during the small packet transmission process in the field of mobile communications. By using a processing scheme that combines the physical layer and the protocol layer, reducing the size of the processing unit LDU in the physical layer, reserving protocol overhead, without waiting to send the entire TB block, and through means such as compact definition, compression, fragmentation and recombination in the protocol layer, to ensure the accuracy and orderliness of the transmission process, and to ensure low latency, so as to meet the throughput and latency requirements in the scenario of high throughput and a large number of small packets.

[0006] Technical solution: A high-performance small packet transmission method, including the following steps:

[0007] Step S1, physical layer design. By reducing the size of the processing unit LDU at the physical layer, reserving protocol overhead, and not waiting to send the entire TB block, the purpose of fast transmission is achieved, including:

[0008] Step S11, reducing the size of the processing unit LDU;

[0009] Step S12, physical layer reserving protocol overhead: Calculate the data transmission requirements shared per time slot according to the throughput requirement, and on this basis, increase the capacity by 10% and reserve it for protocol overhead; The size of the LDU already includes the reserved protocol overhead to ensure that the protocol layer has sufficient resources for processing;

[0010] Step S2, protocol layer design. Divide the protocol layer into two layers, the LDU layer and the UDU layer:

[0011] Among them, the LDU layer is used to define a 3-byte LDU header Type1. Among the N LDU transmissions per time slot, only the first one carries Type1 to reduce protocol overhead;

[0012] Among them, the UDU layer is used to define a 5-byte UDU header Type2. The UDU payload is the user data to be transmitted. The UDU layer implements fragmentation and recombination. Each LDU carries 1-2 UDUs. When there are less than 5 bytes remaining in the LDU, the next user data is transmitted by default without carrying the UDU header;

[0013] Step S3, fragmentation and recombination, including:

[0014] Fragmentation mechanism: Each LDU carries 1-2 UDUs. When there are less than 5 bytes remaining in the LDU, the next user data is transmitted by default;

[0015] Recombination mechanism: The receiving end recombines multiple UDUs into a complete data packet according to the fragmentation identifier and user data identifier in the UDU header;

[0016] Step S4, transmission process, including the sending method and the receiving method.

[0017] According to another aspect of the present application, step S11 is specifically:

[0018] Step S111, at the physical layer, reduce the size of the processing unit LDU to be sent, and use it to send the LDU to be sent to the air interface;

[0019] Step S112, demodulate the LDU that has been sent to the air interface;

[0020] Step S113: Send the demodulated LDU to the upper layer without waiting for the transmission and reception of the entire time slot data; where each LDU has a fixed SIZE ldu bytes, and N TB LDUs are transmitted per time slot, and N TB is determined according to actual requirements and throughput requirements.

[0021] According to another aspect of the present application, the specific definition of Type1 in step S2 includes:

[0022] Quadruple address: source address, destination address, previous hop address, next hop address;

[0023] Udu count: The total number of UDUs included in all LDUs within this time slot;

[0024] The sending end ensures that the data transmitted within the time slot is of the same flow, and Type1 does not need to be resent.

[0025] According to another aspect of the present application, the specific definition of Type2 in step S2 includes:

[0026] SI: Fragmentation identifier, where 00 means no fragmentation, 01 means the first fragment, 10 means the last fragment, and 11 means the middle fragment;

[0027] SN: A sequence number for each service data packet SDU, which is an incrementing value;

[0028] OFFSET: The starting position of the fragment in the SDU;

[0029] LEN: The data length of the UDU.

[0030] According to another aspect of the present application, the fragmentation mechanism in step S3 specifically includes:

[0031] User data fragmentation: Fragment the user data into multiple UDUs, and the payload length of each UDU does not exceed 11 bytes;

[0032] LDU encapsulation: Each LDU carries 1 - 2 UDUs. When there are less than 5 bytes remaining in the LDU, the next user data is transmitted by default without carrying the UDU header.

[0033] According to another aspect of the present application, the recombination mechanism in step S3 specifically includes:

[0034] Receiver parsing: The receiver parses the Type1 header to obtain the time slot identifier and the sequence number;

[0035] UDU parsing: Parse the Type2 header to obtain the user data identifier and the fragmentation identifier;

[0036] Data Reorganization: Reorganize multiple UDUs into a complete data packet according to the shard identifier and user data identifier.

[0037] According to another aspect of the present application, the specific process of sending in step S4 includes:

[0038] When sending in each time slot, sequentially take out SDUs from the queue, and calculate the maximum length that can be sent this time according to the remaining size SIZE of the LDU. The calculation method is as follows: lduleft Calculate the maximum length that can be sent this time. The calculation method is as follows:

[0039] length = min(len sdu - offset, SIZE lduleft <= HdrLen udu ? SIZE lduleft : SIZE lduleft - HdrLen udu ); where

[0041] Determine SI and SN according to offset and length;

[0042] Set the UDU header, complete the encapsulation, and save SN and offset;

[0043] Repeat this process until the LDU is completely encapsulated. If the remaining number of bytes in the LDU is not enough to encapsulate the UDU header, skip setting the UDU header; if only the SDU is encapsulated, but the offset and SN information still need to be determined and saved according to the normal process to continue encapsulating the remaining part of the SDU in the next LDU;

[0044] After the LDU is completely encapsulated, send it immediately;

[0045] Repeat the above process until N TB LDUs are sent, or there is no data to send.

[0046] According to another aspect of the present application, the specific process of receiving in step S4 includes:

[0047] Index the receive queue with the LDU src and record the address information to facilitate continued reception of subsequent LDUs without an LDU header, and record the UDU SN ;

[0048] If UDU SN != UDU SNSAVED , immediately deliver the received shards of this SDU to the upper layer, and increment UDU SNSAVED ; if UDU SI is not fragmented, immediately deliver this SDU to the upper layer, and increment UDU SNSAVED ;

[0049] If UDUSI For the last fragment, complete the recombination and immediately deliver the SDU to the upper layer, the UDU SNSAVED Increment;

[0050] Save the fragmentation information.

[0051] Beneficial effects: By reducing the size of the processing unit LDU at the physical layer, reserving protocol overhead, without waiting to send the entire TB block, compactly defining, compressing, and fragmenting and recombining at the protocol layer, etc., to ensure the accurate and orderly transmission process and guarantee low latency; Based on ad-hoc mobile communication, the present invention combines the physical layer and the protocol layer to achieve the requirements of throughput and latency in scenarios with high throughput and mostly small packets. Description of the Drawings

[0052] Figure 1 It is the overall scheme flowchart of the present invention.

[0053] Figure 2 It is the schematic diagram of the SDU encapsulation method of the present invention. Detailed Embodiments

[0054] The applicant believes that in the field of mobile communication, in the transmission scenario with more small packets, the problem of waste of radio resources is likely to occur. If waiting to send data to improve the radio resource utilization rate, a larger delay problem will occur. The present invention combines the physical layer and the protocol layer to provide a small packet fast transmission scheme, that is, a processing scheme combining the physical layer and the protocol layer for the requirements of radio resource utilization rate and delay in the process of small packet transmission in the field of mobile communication: by reducing the size of the processing unit LDU at the physical layer, reserving protocol overhead, without waiting to send the entire TB block, compactly defining, compressing, and fragmenting and recombining at the protocol layer, etc., to ensure the accurate and orderly transmission process and guarantee low latency; Based on ad-hoc mobile communication, the present invention combines the physical layer and the protocol layer to achieve the requirements of throughput and latency in scenarios with high throughput and mostly small packets.

[0055] Such as Figure 1 shown, a high-performance small packet transmission method includes the following steps:

[0056] Step S1, Physical layer design, by reducing the size of the processing unit LDU at the physical layer, reserving protocol overhead, without waiting to send the entire TB block, to achieve the purpose of fast transmission, including:

[0057] Step S11, Reduce the size of the processing unit LDU;

[0058] Step S12, Physical layer reserve protocol overhead: Calculate the data transmission requirements allocated to each time slot according to the throughput requirements, and on this basis, increase the capacity by 10% and reserve it for protocol overhead; The size of the LDU already includes the reserved protocol overhead to ensure that the protocol layer has sufficient resources for processing;

[0059] Step S2, Protocol layer design: The protocol layer is divided into two layers, the LDU layer and the UDU layer:

[0060] Among them, the LDU layer is used to define the 3-byte LDU header Type1. Among the N LDU transmissions in each time slot, only the first one carries Type1, reducing the protocol overhead;

[0061] Among them, the UDU layer is used to define the 5-byte UDU header Type2. The UDU payload is the user data to be transmitted. The UDU layer implements fragmentation and reassembly. Each LDU carries 1-2 UDUs. When there are less than 5 bytes remaining in the LDU, the next user data is transmitted by default without carrying the UDU header;

[0062] Step S3, Fragmentation and reassembly, including:

[0063] Fragmentation mechanism: Each LDU carries 1-2 UDUs. When there are less than 5 bytes remaining in the LDU, the next user data is transmitted by default;

[0064] Reassembly mechanism: The receiving end reassembles multiple UDUs into a complete data packet according to the fragmentation identifier and user data identifier in the UDU header;

[0065] Step S4, Transmission process, including the sending method and the receiving method.

[0066] The design of the physical layer in this solution enables data to be transmitted quickly through the air interface, reducing the transmission delay; the protocol layer design further reduces the transmission delay by reducing the protocol overhead (such as only carrying the Type1 header in the first LDU). The efficient fragmentation mechanism reduces unnecessary protocol overhead and improves the transmission efficiency; the reassembly mechanism ensures the integrity and correctness of the data at the receiving end, while reducing the complexity of reassembly; the physical layer reserved protocol overhead ensures that the protocol layer has sufficient resources for processing, while avoiding transmission failures caused by insufficient protocol overhead; the protocol layer optimization reduces unnecessary protocol overhead by defining the Type1 and Type2 headers, especially by only carrying the Type1 header in the first LDU in the LDU layer, further improving the transmission efficiency; the efficient transmission process: the sending process ensures the efficient transmission of data while avoiding unnecessary waiting and delay; the receiving process enables the receiving end to quickly reassemble the data packet by parsing the Type1 and Type2 headers and deliver it to the upper layer, improving the receiving efficiency; the flexible LDU size enables the system to flexibly adapt to different transmission requirements, improving the adaptability and scalability of the system; through the fragmentation identifier and user data identifier, the receiving end can accurately identify and reassemble the data packet, ensuring the reliability and integrity of the data transmission.

[0067] In summary, through the optimized design of the physical layer and the protocol layer, the present technical solution realizes high-performance small packet transmission, and has technical effects such as fast sending, low latency, efficient fragmentation and reassembly mechanisms, flexible protocol overhead management, efficient transmission processes, and strong adaptability.

[0068] According to another aspect of the present application, step S11 is specifically as follows:

[0069] Step S111: At the physical layer, reduce the size of the processing unit LDU to be sent to send the LDU to be sent to the air interface;

[0070] Step S112: Demodulate the LDU that has been sent to the air interface;

[0071] Step S113: Send the demodulated LDU to the upper layer without waiting for the sending and receiving of the entire time slot data; wherein, each LDU has a fixed SIZE ldu bytes, and N TB LDUs are transmitted per time slot, and N TB is determined according to actual requirements and throughput requirements.

[0072] According to another aspect of the present application, the specific definition of Type1 in step S2 includes:

[0073] Quadruple address: source address, destination address, previous hop address, next hop address;

[0074] Udu count: The total number of UDUs included in all LDUs within this time slot;

[0075] The sending end ensures that the data transmitted within the time slot is of the same flow, and Type1 does not need to be resent.

[0076] According to another aspect of the present application, the specific definition of Type2 in step S2 includes:

[0077] SI: Fragmentation flag, where 00 means no fragmentation, 01 means the first fragment, 10 means the last fragment, and 11 means the middle fragment;

[0078] SN: A sequence number for each service data packet SDU, which is an incrementing value;

[0079] OFFSET: The starting position of the fragment in the SDU;

[0080] LEN: The data length of the UDU.

[0081] According to another aspect of the present application, the fragmentation mechanism in step S3 specifically includes:

[0082] User data fragmentation: Fragment the user data into multiple UDUs, and the payload length of each UDU does not exceed 11 bytes;

[0083] LDU encapsulation: Each LDU carries 1 - 2 UDUs. When there are less than 5 bytes remaining in the LDU, the next user data is transmitted by default without carrying the UDU header.

[0084] According to another aspect of the present application, the recombination mechanism in step S3 specifically includes:

[0085] Receiver parsing: The receiver parses the Type1 header to obtain the time slot identifier and sequence number;

[0086] UDU parsing: Parse the Type2 header to obtain the user data identifier and fragmentation identifier;

[0087] Data recombination: Recombine multiple UDUs into a complete data packet according to the fragmentation identifier and user data identifier.

[0088] According to another aspect of the present application, the specific process of sending in step S4 includes:

[0089] When sending per time slot, take out the SDUs from the queue in sequence, and calculate the maximum length that can be sent this time according to the remaining size SIZE of the LDU. The calculation method is as follows: lduleft Calculate the maximum length that can be sent this time. The calculation method is as follows:

[0090] length = min(len sdu - offset, SIZE lduleft <= HdrLen udu ? SIZE lduleft : SIZE lduleft - HdrLen udu ); where

[0092] Determine SI and SN according to offset and length;

[0093] Set the UDU header, complete the encapsulation, and save SN and offset;

[0094] Repeat this process until the LDU is completely encapsulated. If the remaining bytes in the LDU are not enough to encapsulate the UDU header, skip setting the UDU header; if only the SDU is encapsulated, the offset and SN information still need to be determined and saved according to the normal process so that the remaining part of the SDU can be encapsulated in the next LDU;

[0095] After the LDU is completely encapsulated, send it;

[0096] Repeat the above process until N TB LDUs are sent, or there is no data to send.

[0097] According to another aspect of the present application, the specific process of receiving and sending in step S4 includes:

[0098] Use the LDU src to index the receive queue and record the address information to facilitate the continued reception of subsequent LDUs without LDU headers, and record the UDU SN ;

[0099] If the UDU SN != UDU SNSAVED , immediately deliver the received fragments of the SDU to the upper layer, and increment the UDU SNSAVED ; If the UDU SI is not fragmented, immediately deliver the SDU to the upper layer, and increment the UDU SNSAVED ;

[0100] If the UDU SI is the last fragment, complete the recombination, immediately deliver the SDU to the upper layer, and increment the UDU SNSAVED ;

[0101] Save the fragmentation information.

[0102] It should be noted that, in the above specific embodiments, the various specific technical features described can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention does not separately describe various possible combination methods.

Claims

1. A high-performance small packet transmission method, characterized in that: The steps include: Step S1, physical layer design, reducing the size of the processing unit LDU through the physical layer, reserving the protocol overhead, and achieving the purpose of fast transmission without waiting to send the entire TB block, including: Step S11, reducing the size of the processing unit LDU; Step S12, physical layer reserved protocol overhead: calculate the data transmission requirement shared to each time slot according to the throughput requirement, and increase the capacity by 10% on this basis to reserve for the protocol overhead; the LDU size already includes the reserved protocol overhead, ensuring that the protocol layer has sufficient resources for processing; Step S2: Protocol layer design, dividing the protocol layer into two layers: LDU layer and UDU layer: The LDU layer is used to define the 3-byte LDU header Type 1. In the N LDU transmissions in each time slot, only the first one carries Type 1, which reduces the protocol overhead. The UDU layer is used to define a 5-byte UDU header Type 2. The UDU payload is the user data to be transmitted. The UDU layer implements fragmentation and reassembly. Each LDU carries 1-2 UDUs. When there are less than 5 bytes left in the LDU, the next user data is transmitted by default without carrying the UDU header. Step S3, fragmentation and reorganization, includes: Fragmentation mechanism: Each LDU carries 1-2 UDUs. When there are less than 5 bytes left in the LDU, the next user data is transmitted by default. Reassembly mechanism: The receiving end reassembles multiple UDUs into a complete data packet based on the fragment identifier and user data identifier in the UDU header; Step S4: Transmission process, including sending method and receiving method.

2. A high-performance packet transmission method as claimed in claim 1, characterized in that: Step S11 is specifically as follows: Step S111: reducing the size of the processing unit LDU to be sent at the physical layer so as to send the LDU to be sent to the air interface; Step S112: demodulate the LDU sent to the air interface; Step S113: Send the demodulated LDU to the upper layer without waiting for the transmission and reception of the entire time slot data; wherein each LDU has a fixed size ldu Bytes, N transmitted per time slot TB LDU, N TB Determined based on actual demand and throughput requirements.

3. A high-performance packet transmission method as claimed in claim 1, characterized in that: The Type 1 definition in step S2 specifically includes: Four-tuple address: source address, destination address, previous hop address, next hop address; Udu count: the total number of UDUs contained in all LDUs in this time slot; The sender ensures that the data transmitted in the time slot is the same stream, and Type1 does not need to be sent repeatedly.

4. A high-performance packet transmission method as claimed in claim 1, characterized in that: The Type2 definition in step S2 specifically includes: SI: fragmentation identifier, where 00 indicates no fragmentation, 01 indicates the first fragment, 10 indicates the last fragment, and 11 indicates the middle fragment; SN: a sequence number of each service data packet SDU, which is an increasing value; OFFSET: The starting position of the fragment in the SDU; LEN: UDU data length.

5. A high-performance packet transmission method as claimed in claim 1, characterized in that: The sharding mechanism in step S3 specifically includes: User data fragmentation: User data is fragmented into multiple UDUs, and the payload length of each UDU does not exceed 11 bytes; LDU encapsulation: Each LDU carries 1-2 UDUs. When there are less than 5 bytes left in the LDU, the next user data is transmitted by default without carrying the UDU header.

6. A high-performance packet transmission method as claimed in claim 1, characterized in that: The recombination mechanism in step S3 specifically includes: Parsing at the receiving end: The receiving end parses the Type1 header to obtain the time slot identifier and sequence number; UDU parsing: parse the Type2 header to obtain the user data identifier and fragment identifier; Data reassembly: Reassemble multiple UDUs into a complete data packet based on the fragment identifier and user data identifier.

7. A high-performance packet transmission method as claimed in claim 1, characterized in that: The specific process of sending in step S4 includes: When each time slot is sent, the SDU is taken out from the queue in sequence, and the remaining size of the LDU is calculated according to the size of the LDU. lduleft Calculate the maximum length that can be sent this time. The calculation method is as follows: length = min(len sdu - offset, SIZE lduleft <= HdrLen udu ? SIZE lduleft : SIZE lduleft - HdrLen udu ); where Determine SI and SN based on offset and length; Set the UDU header, complete the encapsulation, and save the SN and offset; Repeat this process until the LDU is encapsulated. If the remaining bytes of the LDU are not enough to encapsulate the UDU header, the UDU header is skipped. If only the SDU is encapsulated, but the offset and SN information still need to be determined and saved according to the normal process, so that the remaining part of the SDU can be encapsulated in the next LDU. After LDU is encapsulated, it is sent; Repeat the above process until N TB LDUs are sent, or there is no data to send.

8. A high-performance packet transmission method as claimed in claim 1, characterized in that: The specific process of receiving and sending in step S4 includes: LDU src Index the receiving queue and record the address information to facilitate the continued reception of subsequent LDUs without LDU headers and record UDUs SN ; If UDU SN ! =UDU SNSAVED , immediately submit the received fragment of the SDU to the upper layer, UDU SNSAVED Incremental; If UDU SI Unfragmented, that is, the SDU is immediately submitted to the upper layer, UDU SNSAVED Incremental; If UDU SI For the final fragmentation, complete the reassembly and immediately submit the SDU to the upper layer, UDU SNSAVED Incremental; Save the shard information.

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