CN106254202A - A kind of multidiameter delay transmission method based on fountain codes and device - Google Patents

Abstract

The invention discloses a multi-channel parallel transmission method and device based on fountain codes. Wherein, the method includes: respectively buffering the original data packets to be sent according to the address of the receiving end; judging whether the number of original data packets in the cache reaches a preset number or whether the waiting time exceeds a preset value; Fountain encoding is performed on the original data packets in , respectively, to obtain encoded data packets; the overall status of multiple tunnels used to transmit encoded data packets is obtained, which can be divided into two cases: good overall performance and poor overall performance, and thus select the corresponding transmission Mode, in the corresponding transmission mode, select the corresponding tunnel for the encoded data packet according to the degree value of the encoded data packet, and adjust its transmission mode accordingly at different stages in the transmission process of the encoded data packet; set a feedback module at the receiving end, This enables the sending end to judge whether the transmission process is completed, thereby realizing multi-channel parallel transmission of original data packets, and improving link utilization and transmission reliability.

Description

A method and device for multi-channel parallel transmission based on fountain codes

technical field

The present invention relates to the field of virtual private network, in particular to a fountain code-based multi-channel parallel transmission method and device.

Background technique

Tunnel is a key technology for realizing a virtual private network (Virtual Private Network, VPN), and its basic function is encapsulation, which is mainly realized by using a tunnel protocol. The tunnel protocol encapsulates the data frame or data packet of one network protocol into the data frame of another network protocol, establishes a virtual private connection between the two hosts, and the encapsulated data packet is transmitted like a normal data packet, realizing Transfer private data over public networks. Based on the widely distributed Internet network, VPN tunnels are easy to deploy, low in cost, and good in scalability, and are widely used in enterprise networks. However, due to bandwidth limitations, node congestion, firewall filtering and other factors, there will be packet loss in the tunnel, and the transmission performance will fluctuate. If the tunnel is established based on UDP (User Datagram Protocol, User Datagram Protocol), packet loss will reduce the reliability of network transmission, application data cannot be transmitted correctly, and affect user experience; if the tunnel is established based on TCP (Transmission Control Protocol, Transmission Control Protocol) , although the TCP protocol can improve the reliability of data transmission, packet loss will cause a large number of retransmission packets in the network, seriously affecting network throughput.

With the rapid development of network technology, a large number of multimedia services have emerged. These services have a large amount of data and have high requirements for real-time and reliability of data transmission. The traditional single-path TCP-based transmission mode has been It is difficult to meet business needs. When network congestion occurs or link performance fluctuates greatly, a large number of ACK (Acknowledgment, confirmation character) confirmation packets and retransmission packets will appear in the network, which increases network load and aggravates network congestion. There will also be network paralysis. In order to make full use of network resources, IETF (Internet Engineering Task Force, Internet Engineering Task Force) proposed the Multipath Transmission Control Protocol (MPTCP), which can apply MPTCP (MultiPath TCP, Multipath Transmission Control Protocol) to the tunnel to realize the tunnel Load balancing among them to improve the throughput of the network. However, MPTCP is only an extension of the traditional TCP protocol, which is equivalent to establishing a multi-channel TCP connection, but the sender still only selects one of the paths for data transmission, which cannot make full use of the advantages of multi-path, and there is still room for improvement .

The tunnel is built based on the existing public network, and multiple tunnel paths can be established between nodes at both ends to realize parallel multiplex transmission. At present, although there are some schemes using fountain codes to realize multiplex transmission, these schemes are all realized by performing fountain codes on the application layer or transport layer, and there are few precedents of using fountain codes in the network layer. There are no related schemes for tunnel reliability.

Contents of the invention

The purpose of the present invention is to provide a method and device for multi-channel parallel transmission based on fountain codes. Wherein, the method can not only effectively improve the transmission reliability of the tunnel, but also adopt multi-tunnel parallel transmission to realize load balancing between tunnels, reduce congestion, and improve network throughput.

In order to achieve the above object, the present invention provides a multi-channel parallel transmission method based on fountain codes. The methods include:

Obtaining the corresponding receiving end address according to the destination address of the original data packet to be sent, and buffering the original data packet to be sent in different queues according to the receiving end address;

For each queue, determine whether the number of original data packets in the queue reaches a preset number or whether the waiting time of the original data packets in the queue exceeds a preset time;

When judging that the number of original data packets in the queue reaches the preset number or the waiting time of the original data packets in the queue exceeds the preset time, performing fountain encoding on the original data packets cached in the queue respectively to obtain encoded data packets;

Obtaining the overall status of multiple tunnels used to transmit the encoded data packets, and selecting a corresponding transmission mode according to the overall status, and in the corresponding transmission mode, according to the degree value of the encoded data packets, the encoding The data packet selects a corresponding tunnel, and adjusts its transmission mode correspondingly at different stages in the transmission process of the encoded data packet, so as to realize multiple parallel transmissions of the original data packet.

Optionally, before obtaining the corresponding receiver address according to the destination address of the original data packet to be sent, the method further includes:

According to the preset routing algorithm, multiple disjoint path sets between itself and any receiving end are obtained.

Optionally, the method also includes:

receiving the decoding information fed back by the receiving end for decoding the encoded data packet, and stopping the transmission of the encoded data packet when the receiving end has successfully decoded the original data packet according to the decoding information, and sending the next batch of Raw packets are processed and transmitted in the same way.

Optionally, the corresponding transmission mode is selected according to the overall situation, and in the corresponding transmission mode, the corresponding tunnel is selected for the encoded data packet according to the degree value of the encoded data packet, and in the encoding Different stages in the packet transmission process adjust their delivery accordingly, including:

When it is judged according to the overall condition that the overall transmission performance of the multiple tunnels is good,

Evaluate and classify the transmission quality of each tunnel according to the delay, bandwidth, arrival rate of each tunnel, and the correlation between tunnels, and obtain the priority order of multiple tunnels.

Using the first encoded data packet whose priority is higher than the set value of the tunnel transmission degree value is lower than the preset value, and the priority is lower than the set value The second encoded data packet whose tunnel transmission degree value is higher than the preset value ,

When the number of transmissions of the first encoded data packets reaches the first preset number, transmit the second encoded data packets using a tunnel with a priority higher than the set value, and a priority lower than the set value tunneling of said first encoded data packet;

In the case where the overall transmission performance of the plurality of tunnels is judged to be poor according to the overall condition,

transmitting said first encoded data packet on all tunnels,

When the number of transmissions of the first encoded data packets reaches a second preset number, the second encoded data packets are transmitted on all tunnels.

Correspondingly, the present invention also provides a multi-channel parallel transmission device based on fountain codes. The devices include:

The first buffer module is used to obtain the corresponding receiving end address according to the destination address of the original data packet to be sent, and cache the original data packet to be sent in different queues according to the receiving end address;

The first judging module is used for, for each queue, judging whether the number of original data packets in the queue reaches a preset number or whether the waiting time of the original data packets in the queue exceeds a preset time;

The fountain code encoding module is used to perform fountain encoding on the original data packets cached in the queue respectively when the number of original data packets in the judging queue reaches a preset number or the waiting time of the original data packets in the queue exceeds a preset time, Get the encoded data packet;

A packet scheduling module, configured to obtain the overall status of multiple tunnels used to transmit the encoded data packets, and select a corresponding transmission mode according to the overall status, and in the corresponding transmission mode, according to the overall status of the encoded data packets The degree value selects a corresponding tunnel for the encoded data packet, and adjusts its transmission mode correspondingly at different stages in the transmission process of the encoded data packet, so as to realize multiple parallel transmissions of the original data packet.

Optionally, the device also includes:

The path management module is configured to calculate multiple disjoint path sets between itself and any receiving end according to a preset routing algorithm.

Optionally, the group scheduling module is also used for:

receiving the decoding information fed back by the receiving end for decoding the encoded data packet, and stopping the transmission of the encoded data packet when the receiving end has successfully decoded the original data packet according to the decoding information, and sending the next batch of Raw packets are processed and transmitted in the same way.

Optionally, the group scheduling module is specifically used for:

When it is judged according to the overall condition that the overall transmission performance of the multiple tunnels is good,

Evaluate and classify the transmission quality of each tunnel according to the delay, bandwidth, arrival rate of each tunnel, and the correlation between tunnels, and obtain the priority order of multiple tunnels.

Using the first encoded data packet whose priority is higher than the set value of the tunnel transmission degree value is lower than the preset value, and the priority is lower than the set value The second encoded data packet whose tunnel transmission degree value is higher than the preset value ,

When the number of transmissions of the first encoded data packets reaches the first preset number, transmit the second encoded data packets using a tunnel with a priority higher than the set value, and a priority lower than the set value tunneling of said first encoded data packet;

In the case where the overall transmission performance of the plurality of tunnels is judged to be poor according to the overall condition,

transmitting said first encoded data packet on all tunnels,

When the number of transmissions of the first encoded data packets reaches a second preset number, the second encoded data packets are transmitted on all tunnels.

Correspondingly, the present invention also provides a multi-channel parallel transmission method based on fountain codes. The methods include:

receiving multiple tunnel-transmitted data packets, decapsulating the data packets using a tunneling protocol, and filtering to obtain encoded data packets;

respectively buffering the encoded data packets in different queues according to the source addresses of the encoded data packets;

For each queue, determine whether the number of encoded data packets in the queue reaches the number required for decoding;

When it is judged that the number of encoded data packets in the queue reaches the number required for decoding, fountain decoding is performed on the encoded data packets buffered in the queue to obtain original data packets, thereby realizing multi-channel parallel transmission of the original data packets.

Optionally, the method also includes:

Feedback decoding information to the sending end according to the decoding situation, so that the sending end stops transmitting the encoded data packets according to the decoding information, and performs the same processing and transmission on the next batch of original data packets.

Correspondingly, the present invention also provides a multi-channel parallel transmission device based on fountain codes. The devices include:

A receiving module, configured to receive multiple tunnel-transmitted data packets, and use a tunneling protocol to decapsulate the data packets, and filter to obtain encoded data packets;

A second cache module, configured to respectively cache the encoded data packets in different queues according to the source address of the encoded data packets;

The second judging module is used for, for each queue, judging whether the number of encoded data packets in the queue reaches the number required for decoding;

Fountain code decoding module, for judging that the number of encoded data packets in the queue reaches the number required for decoding, fountain decoding is performed on the encoded data packets cached in the queue respectively to obtain the original data packets, thereby realizing the original data packets multiple parallel transmissions.

Optionally, the device also includes:

The feedback module is configured to feed back decoding information to the sending end according to the decoding situation, so that the sending end stops transmitting the encoded data packets according to the decoding information, and performs the same processing and transmission on the next batch of original data packets.

It can be seen from the above technical solution that the original data packets to be sent to the same receiving end are buffered, and after the original data packets reach the preset number or after the original data packets wait for timeout, fountain coding is performed on the original data packets to obtain encoded data packets. Then, select the corresponding tunnel for the encoded data packet according to the overall state of the tunnel and the degree value of the encoded data packet, and transmit the encoded data packet to the receiving end in parallel, and the receiving end uses the tunneling protocol to decapsulate the data packets transmitted by multiple tunnels , to filter the encoded data packets, and cache the encoded data packets in different queues according to the source address of the encoded data packets. When it is judged that the number of encoded data packets in the queue reaches the number required for decoding, the Encoded data packets are decoded separately to obtain original data packets, which can not only effectively improve the transmission reliability of the tunnel, but also use multi-tunnel parallel transmission to achieve load balancing between tunnels, reduce congestion, and improve network throughput.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings that are required in the description of the embodiments or the prior art. Apparently, the drawings in the following description are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

Fig. 1 is a flow chart of a multi-channel parallel transmission method based on fountain codes provided by an embodiment of the present invention;

Fig. 2 is a schematic structural diagram of a multi-channel parallel transmission device based on fountain codes provided by an embodiment of the present invention;

3 is a flowchart of a fountain code-based multi-channel parallel transmission method provided by an embodiment of the present invention;

Fig. 4 is a schematic structural diagram of a multi-channel parallel transmission device based on fountain codes provided by an embodiment of the present invention;

Fig. 5 is a working flow diagram of a multi-channel parallel transmission method based on fountain codes provided by an embodiment of the present invention;

Fig. 6 is a schematic diagram of an overall structural model of a sending end and a receiving end provided by an embodiment of the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Some words mentioned in the embodiments of the present invention are explained below.

Fountain code is a "rateless" code whose code rate can be adjusted in real time as the channel transmission conditions change. The sending end does not need to pre-set the code rate, and can generate any number of encoded packets from k original data packets, and then send the packaged encoded data packets in a certain way; the receiving end only needs to receive enough packets, The original data packet can be recovered without considering which data packets are received and in what order these data packets are received, and there is no need to confirm the received data. Therefore, the fountain code is suitable for communication scenarios that do not know the channel conditions and are greatly affected by certain uncertain factors. The emergence of fountain codes has opened up new ideas for improving network reliability and network transmission efficiency. It has been widely used in large-scale network information distribution, reliable multicast transmission, wireless cooperative transmission and other scenarios, and is being extended to more and more more fields of application. The invention applies the advantages of the fountain code to the tunnel communication scene to improve the transmission reliability of the tunnel, and at the same time, adopts multi-tunnel parallel transmission to realize load balancing between tunnels, reduce congestion, and improve network throughput.

FIG. 1 is a flowchart of a fountain code-based multi-channel parallel transmission method provided by an embodiment of the present invention. As shown in FIG. 1, a fountain code-based multi-channel parallel transmission method provided by an embodiment of the present invention includes:

In step S101, the corresponding receiving end address is obtained according to the destination address of the original data packet to be sent, and the original data packet to be sent is respectively buffered in different queues according to the receiving end address.

Specifically, the VPN server as the sending end can obtain the corresponding address of the VPN server as the receiving end according to the destination address of the original data packet to be sent, and buffer the original data packets to be sent to the same VPN server in the same queue, that is to say , each queue corresponds to the same VPN server as the receiving end.

More specifically, before this step, the method further includes: calculating multiple disjoint path sets between itself and any receiving end according to a preset routing algorithm. The VPN servers in the network establish a layer-3 tunnel connection through mutual authentication to form a tunnel-based VPN network. The VPN server as the sending end can calculate multiple disjoint path sets between itself and the receiving end through preset routing algorithms.

Next, in step S102, for each queue, it is judged whether the number of original data packets in the queue reaches a preset number or whether the waiting time of the original data packets in the queue exceeds a preset time.

Wherein, the preset number is the number of original data packets required by fountain coding.

Next, in step S103, when it is judged that the number of original data packets in the queue reaches the preset number or the waiting time of the original data packets in the queue exceeds the preset time, the original data packets buffered in the queue are respectively subjected to fountain encoding , to get the encoded data packet.

Specifically, if the number of original data packets in the queue reaches the preset number within the preset time, fountain coding can be performed on the original data packets cached in the queue to obtain encoded data packets; if the number of original data packets in the queue If the preset number is not reached, but the waiting time of the original data packets exceeds the preset time, the original data packets buffered in the queue can be fountain encoded to obtain encoded data packets.

More specifically, when it is judged that the number of original data packets in the queue does not reach the preset number or the waiting time of the original data packets in the queue does not exceed the preset time, continue to wait until the number of original data packets in the queue reaches the preset number. Set the number or wait time of raw packets in the queue for more than a preset time.

Finally, in step S104, the overall conditions of the multiple tunnels used to transmit the encoded data packets are acquired, and a corresponding transmission mode is selected according to the overall conditions, and in the corresponding transmission mode, according to the encoded data packets The degree value of is to select a corresponding tunnel for the coded data packet, and adjust its transmission mode correspondingly at different stages in the transmission process of the coded data packet, so as to realize multi-channel parallel transmission of the original data packet.

Specifically, selecting the corresponding transmission mode according to the overall situation, and in the corresponding transmission mode, and adjusting the transmission mode correspondingly at different stages in the transmission process of the encoded data packet, according to the encoded data packet The degree value of is to select the corresponding tunnel for the coded data packet, including: under the condition that the overall transmission performance of the plurality of tunnels is judged to be good according to the overall condition, according to the delay (latency), bandwidth ( bandwidth), arrival rate (delivery rate) and the correlation (jointness) between tunnels to evaluate and classify the transmission quality of each tunnel, get the priority order of multiple tunnels, and use the tunnel transmission with a priority higher than the set value The first coded data packet whose degree value is lower than the preset value, the tunnel transmission second coded data packet whose degree value is higher than the preset value, and the transmission of the first coded data packet When the number reaches the first preset number, the second encoded data packet is transmitted using a tunnel with a priority higher than the set value, and the tunnel with a priority lower than the set value is used to transmit the first encoded data packet packets; if the overall transmission performance of the plurality of tunnels is judged to be poor according to the overall condition, transmit the first encoded data packets on all tunnels, and when the number of transmissions of the first encoded data packets reaches the second In the case of two preset numbers, the second coded data packet is transmitted on all tunnels. Wherein, the first encoded data packet refers to an encoded data packet whose degree value is lower than a preset value, and the second encoded data packet refers to an encoded data packet whose degree value is higher than a preset value.

The degree distribution used in digital fountain encoding is a key factor affecting encoding performance and decoding efficiency. The existence of low degree values can ensure the start of the decoding process, and the existence of high values can ensure that all source data (original data) can participate in encoding , so as not to omit the original information. A reasonable degree distribution design can allow the VPN server as the receiving end to recover all original data packets from as few encoded data packets as possible. Here, this application considers designing in combination with fountain code degree distribution characteristics and tunnel multipath characteristics to improve link utilization and decoding success rate. When designing how to use existing multiple paths for parallel encoded data packet transmission, considering the different transmission performance of tunnels, the following two transmission modes are designed:

Mode 1: The overall transmission performance of the tunnel is good

Evaluate and classify the transmission quality of each path according to the delay, bandwidth, arrival rate and correlation between paths of each path, and set the corresponding path priority from high to low according to the quality from good to bad. For example, in the actual tunnel, there are a total of 10 tunnels, and the priority can be set to level one, level two, and level three according to the quality from good to bad. Among them, there are four tunnels in the first level and three tunnels in the second level There are 3 grade-3 tunnels.

For example, when actually transmitting encoded data packets, every 10 original data packets can be regarded as a packet, and after they are fountain-encoded, they are sent to the tunnel for multiplexing until the receiving end can successfully decode the original data packets. Perform the same processing and transmission on the next original data packet group. Specific to the transmission of encoded data packets, it is divided into the following two stages:

The first stage: the first encoded data packet whose priority is higher than the set value is the first coded data packet whose transmission degree value is lower than the preset value, and the second coded packet whose priority is lower than the set value is higher than the preset value. Encode the packet.

At the beginning of the transmission of encoded data packets, select a path with a priority higher than the set value to transmit the first encoded data packet with a degree value lower than the preset value, and a path with a priority lower than the set value to transmit encoded data with other degree values packets, so that the decoding end receives enough coded data packets with degree 1 and other low degrees, on the one hand to ensure the start of the decoding process, and on the other hand to ensure that the decoder can decode the degree value in the subsequent decoding process Larger encoded packets. In an actual tunnel, first-level and second-level tunnels are selected to transmit the first encoded data packets whose degrees are lower than a preset value, and third-level tunnels are selected to transmit second encoded data packets whose degrees are higher than a preset value.

The second stage: the second coded data packet whose priority is higher than the set value is the second coded data packet whose transmission degree value is higher than the preset value, and the first encoded data packet whose priority is lower than the set value is lower than the preset value. Encode the packet.

After a certain number of encoded data packets can be successfully decoded at the decoding end, if the first encoded data packet whose degree value is lower than the preset value is still given priority, the decoder will receive a lot of redundant encoded data packets, and the The VPN server as the sender needs to generate more encoded data packets to decipher all the original data packets. At this time, enter the second stage of transmission, use several paths with higher priority than the set value instead of the second coded data packet whose transmission degree value is higher than the preset value, and the transmission degree value of the path with priority lower than the set value is low The number of redundant data packets is reduced, and the probability of covering all source data packets is increased, thereby reducing the number of times of transmission of encoded data packets. For example, in an actual tunnel, the first-level and second-level tunnels are selected to transmit the second encoded data packets whose degree values are higher than the preset value, and the third-level tunnels are selected to transmit the first encoded data packets whose degree values are lower than the preset value.

When designing multiplexed fountain encoded packets, it is important to define how many encoded packets enter the second stage. If the number is set too small, the decoder cannot receive enough first encoded data packets whose degree value is lower than the preset value. In this way, when decoding, there may be no encoded data packets with degree 1, and the decoding The encoding process cannot continue; if this number is set too large, the redundant information in the transmission process may be greatly increased. In both cases, the encoder needs to send more encoded packets in order for the decoder to recover the original information. For different actual path conditions, this value can be set reasonably by testing in practice. Specifically, in practice, the packet scheduling module at the sending end debugs according to the decoding situation fed back by the feedback module at the receiving end to obtain the number of encoded data packets entering the second stage of mode 1, that is, the first preset number. The preset number will not be too large, nor too small, not only can the decoding process continue, but also will not increase a large amount of redundant information in the transmission process. Then, the first preset quantity is assigned to the relevant variables of the program, and the program can perform corresponding operations. Due to the fountain encoding of the original data packets, the encoded data packets can be continuously generated at the sending end, and the sending end can stop sending encoded data packets at the receiving end as long as enough encoded data packets are successfully decoded. Adaptive and flexible Sex has increased.

Mode 2: The overall transmission performance of the tunnel is poor

Because the overall transmission performance of the tunnel is not good, the tunnel is no longer classified here. Same as mode 1, every 10 original data packets are regarded as a packet, after they are fountain coded, they are sent to the tunnel for multiplexing, until the receiving end can successfully decode the original data packet, and then the next original data Packets are processed and transmitted in the same way. Specific to the transmission of data packets, it is also divided into two stages:

Phase 1: Transmit the first encoded data packet with degree value lower than the preset value on all tunnels

The overall performance of the tunnel is not good, and the difference between the tunnels is not obvious compared with mode 1. At this time, the same first encoded data packet whose degree value is lower than the preset value is transmitted on all tunnels at the same time, so that the decoding end receives enough On the one hand, encoding data packets with a degree of 1 and other low degrees can be decoded immediately to reduce transmission delay; on the other hand, it can lay a solid foundation for subsequent encoded data packets with higher decoding degrees and improve transmission reliability.

Phase 2: Transmit a second encoded packet with a degree value higher than the preset value on all tunnels

After the decoding end can successfully decode a certain number of encoded data packets, if the first encoded data packet whose degree value is lower than the preset value is still given priority, the decoder will receive a lot of redundant data packets, and the sending end It is necessary to generate more encoded data packets to decipher all the original data packets. At this time, the second stage of transmission is entered, and all the second encoded data packets whose degree value is higher than the preset value are transmitted through the tunnel, covering the probability of all source data packets, so as to ensure that all data packets are decoded. In the second stage, when transmitting the second coded data packet whose degree value is higher than the preset value, different coded data packets can be transmitted on different tunnels to improve transmission efficiency, or the same data packet can be transmitted on different tunnels, through Gain diversity gain to improve transmission reliability.

Same as Mode 1, how to define the certain number of encoded data packets mentioned in the second stage of Mode 2 will be a problem that needs to be considered in actual operation. For different actual path conditions, this value can still be set reasonably through testing in practice. Specifically, in the process of actual operation, the packet scheduling module at the sending end debugs according to the decoding situation fed back by the feedback module at the receiving end to obtain the number of encoded data packets entering the second stage of mode 2, that is, the second preset number. Then, the second preset quantity is assigned to the relevant variables of the program, and the program can perform corresponding operations.

Based on tunnel performance, two transmission modes are designed. Mode 1 reflects the improvement of transmission effectiveness when the tunnel performance is good; mode 2 reflects the improvement of transmission reliability when the tunnel performance is poor. The two modes complement each other and have their own advantages in different application scenarios. In each mode, two transmission stages are designed respectively, fully combining the characteristics of the fountain code, and rationally using the degree value of the encoded data packet to design the transmission scheme.

Preferably, the method further includes: receiving decoding information fed back by the receiving end for decoding the encoded data packet, and stopping transmission of the original data packet when the receiving end successfully decodes the original data packet according to the decoding information Encode the packet, and do the same processing and transmission for the next batch of raw packets. Thereby, the reliability of tunnel multiplex transmission can be further improved.

This embodiment applies the fountain code at the network layer to encode and decode the data packets transmitted between the two networks, and realizes the transparent transmission of the data packets between the two networks. Compared with the deployment at the physical layer and the application layer In other words, the deployment of this embodiment is more efficient, and the protocol only needs to be deployed on the VPN server without changing terminals and other intermediate data forwarding devices. Different from the multi-path transmission method based on the MPTCP protocol, although there are multiple paths, only one path is finally selected for data transmission. This embodiment considers the parallel multiplex transmission of data packets on the network layer, so it can make full use of existing All the tunnels can make full use of the network capacity and improve the tunnel utilization.

For the method embodiment, for the sake of simple description, it is expressed as a series of action combinations, but those skilled in the art should know that the embodiment of the present invention is not limited by the described action order, because according to the embodiment of the present invention , certain steps may be performed in other order or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification belong to preferred embodiments, and the actions involved are not necessarily required by the embodiments of the present invention.

Fig. 2 is a schematic structural diagram of a fountain code-based multi-channel parallel transmission device provided by an embodiment of the present invention. As shown in Figure 2, the multi-channel parallel transmission device based on fountain codes provided by an embodiment of the present invention includes:

The first cache module 201 is used to obtain the corresponding receiving end address according to the destination address of the original data packet to be sent, and cache the original data packet to be sent in different queues according to the receiving end address;

The first judging module 202 is used for, for each queue, judging whether the number of original data packets in the queue reaches a preset number or whether the waiting time of the original data packets in the queue exceeds a preset time;

Fountain code encoding module 203, for judging that the number of original data packets in the queue reaches the preset number or the waiting time of the original data packets in the queue exceeds the preset time, perform fountain encoding on the original data packets cached in the queue respectively , to get the encoded data packet;

A packet scheduling module 204, configured to acquire the overall status of multiple tunnels used to transmit the encoded data packets, and select a corresponding transmission mode according to the overall status, and in the corresponding transmission mode, according to the encoded data packets The degree value of is to select a corresponding tunnel for the coded data packet, and adjust its transmission mode correspondingly at different stages in the transmission process of the coded data packet, so as to realize multi-channel parallel transmission of the original data packet.

In an optional embodiment of the present invention, the device further includes:

The path management module 205 is configured to calculate multiple disjoint path sets between itself and any receiving end according to a preset routing algorithm.

In an optional embodiment of the present invention, the packet scheduling module 204 is further configured to:

receiving the decoding information fed back by the receiving end for decoding the encoded data packet, and stopping the transmission of the encoded data packet when the receiving end has successfully decoded the original data packet according to the decoding information, and sending the next batch of Raw packets are processed and transmitted in the same way.

In an optional embodiment of the present invention, the packet scheduling module 204 is specifically used for:

When it is judged according to the overall condition that the overall transmission performance of the multiple tunnels is good,

Evaluate and classify the transmission quality of each tunnel according to the delay, bandwidth, arrival rate of each tunnel, and the correlation between tunnels, and obtain the priority order of multiple tunnels.

Using the first encoded data packet whose priority is higher than the set value of the tunnel transmission degree value is lower than the preset value, and the priority is lower than the set value The second encoded data packet whose tunnel transmission degree value is higher than the preset value ,

When the number of transmissions of the first encoded data packets reaches the first preset number, transmit the second encoded data packets using a tunnel with a priority higher than the set value, and a priority lower than the set value tunneling of said first encoded data packet;

In the case where the overall transmission performance of the plurality of tunnels is judged to be poor according to the overall condition,

transmitting said first encoded data packet on all tunnels,

When the number of transmissions of the first encoded data packets reaches a second preset number, the second encoded data packets are transmitted on all tunnels.

The specific details involved in the fountain code-based multi-channel parallel transmission device provided by an embodiment of the present invention have been described in detail in the fountain code-based multiple-channel parallel transmission method provided by an embodiment of the present invention, here No longer. The fountain code-based multi-channel parallel transmission device provided by an embodiment of the present invention can be set in the sending end.

Fig. 3 is a flowchart of a fountain code-based multi-channel parallel transmission method provided by an embodiment of the present invention. As shown in FIG. 3, the multi-channel parallel transmission method based on fountain codes provided by an embodiment of the present invention includes:

In step S301, a plurality of tunneled data packets are received, and the tunneling protocol is used to decapsulate the data packets, and the encoded data packets are obtained by filtering.

Specifically, the data packet reaches the VPN server as the receiving end through multiple paths, the tunnel protocol decapsulates the data packet, and filters the encoded data packet in the VPN server.

Next, in step S302, the encoded data packets are respectively buffered in different queues according to the source addresses of the encoded data packets.

Specifically, encoded data packets with the same source address are cached in the same queue, that is, one queue corresponds to one VPN server as the sending end.

Next, in step S303, for each queue, it is judged whether the number of encoded data packets in the queue reaches the number required for decoding.

Finally, in step S304, when it is judged that the number of encoded data packets in the queue reaches the number required for decoding, fountain decoding is performed on the encoded data packets buffered in the queue to obtain the original data packets, thereby realizing the original data packet multiple parallel transmissions.

Specifically, when it is judged that the number of encoded data packets in the queue does not reach the number required for decoding, continue to wait until the number of encoded data packets buffered in the queue reaches the number required for decoding.

Preferably, the method further includes: feeding back decoding information to the sending end according to the decoding situation, so that the sending end stops transmitting the encoded data packets according to the decoding information, and performs the same processing and processing on the next batch of original data packets transmission. Thereby, the reliability of tunnel multiplex transmission can be further improved.

In this embodiment, the original data packets to be sent to the same receiving end are cached, and after the original data packets reach the preset number or after the original data packets wait for timeout, fountain coding is performed on the original data packets to obtain the encoded data packets, and then, according to the tunnel The overall state of the encoded data packet and the degree value of the encoded data packet select the corresponding tunnel, and transmit the encoded data packet to the receiving end in parallel. The receiving end uses the tunnel protocol to decapsulate the data packets transmitted by multiple tunnels, and filters to obtain the encoded data packet. data packets, and cache the encoded data packets in different queues according to the source address of the encoded data packets. Performing fountain decoding to obtain original data packets can not only effectively improve the transmission reliability of the tunnel, but also use multi-tunnel parallel transmission to achieve load balancing between tunnels, reduce congestion, and improve network throughput.

For the method embodiment, for the sake of simple description, it is expressed as a series of action combinations, but those skilled in the art should know that the embodiment of the present invention is not limited by the described action order, because according to the embodiment of the present invention , certain steps may be performed in other order or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification belong to preferred embodiments, and the actions involved are not necessarily required by the embodiments of the present invention.

Fig. 4 is a schematic structural diagram of a fountain code-based multi-channel parallel transmission device provided by an embodiment of the present invention. As shown in Figure 4, the multi-channel parallel transmission device based on fountain codes provided by an embodiment of the present invention includes:

The receiving module 401 is configured to receive multiple tunnel-transmitted data packets, and use a tunneling protocol to decapsulate the data packets, and filter to obtain encoded data packets;

The second caching module 402 is configured to respectively buffer the encoded data packets in different queues according to the source address of the encoded data packets;

The second judging module 403 is used for, for each queue, judging whether the number of encoded data packets in the queue reaches the number required for decoding;

Fountain code decoding module 404, for judging that the number of encoded data packets in the queue reaches the number required for decoding, perform fountain decoding on the encoded data packets cached in the queue respectively to obtain original data packets, thereby realizing the original data Multiple parallel transmission of packets.

In an optional embodiment of the present invention, the device further includes:

The feedback module 405 is configured to feed back decoding information to the sending end according to the decoding situation, so as to regulate the transmission of encoded data packets in multiple tunnels. In addition, it is also used for the sending end to stop transmitting the encoded data packets according to the decoding information, and perform the same processing and transmission on the next batch of original data packets.

The specific details involved in the fountain code-based multi-channel parallel transmission device provided by an embodiment of the present invention have been described in detail in the fountain code-based multiple-channel parallel transmission method provided by an embodiment of the present invention, here No longer. The fountain code-based multi-channel parallel transmission device provided by an embodiment of the present invention can be set in the receiving end.

Fig. 5 is a working flowchart of a fountain code-based multi-channel parallel transmission method provided by an embodiment of the present invention. As shown in Figure 5, the specific workflow steps are as follows:

Step (1), the VPN server (hereinafter referred to as the server) in the network establishes respectively three layers of tunnel connections through mutual authentication, forming a tunnel-based VPN network;

Step (2), the path management module obtains multiple disjoint path sets between any two servers through a routing algorithm;

Step (3), in the sender server, obtain the corresponding destination VPN server address according to the destination address of the IP packet to be sent, and cache the IP packets in different queues respectively according to the destination server address;

Step (4), for each cache queue, judge whether the number of data packets in the queue reaches the encoding requirement of the fountain code, or whether the wait is timed out, if so, carry out fountain coding to the data packets in the queue, and proceed to the next step, If not, proceed to step (3);

Step (5), the packet scheduling module selects the corresponding transmission mode according to the tunnel state, selects the corresponding tunnel for each encoded data packet in the corresponding mode to send, and the tunnel (sub-path) encapsulates the encoded data packet and sends the data packet.

Step (6), the data packet arrives at the receiver server through multiple paths, the tunnel protocol decapsulates the data packet, filters out the encoded data packet in the receiving server, and caches them respectively according to the source server address of the encoded data packet;

In step (7), the encoded data packet of the same source address is sent to the decoding module for decoding after reaching the decoding requirement, and the decoding situation is fed back to the packet scheduling module in the step (5) to participate in the path distribution of the data packet;

In step (8), the decoded data packet is handed over to the IP protocol for processing.

The tunnel is built based on the existing public network. According to a certain routing algorithm, multiple paths with different quality conditions between the sending end and the receiving end can be obtained. In order to improve the reliability of the tunnel communication network, reduce the impact of packet loss on network performance, and improve network throughput, the present invention combines the advantages of multi-channel transmission and fountain codes, and proposes a tunnel multi-channel parallel reliable transmission method based on fountain codes and device. The basic idea is: firstly calculate the multiple path sets between the sending end and the receiving end server according to the routing algorithm, and then cache the IP data packets to be sent to the same destination VPN server in the VPN server at the sending end, After the number of data packets reaches the encoding requirement, it is sent to the encoding module for encoding. Finally, the packet scheduling module selects the corresponding tunnel for the encoding packet to send out according to the degree value of the encoding packet and the information fed back by the feedback module. When the tunnel is encapsulated, the transport layer can The UDP protocol is used to ensure real-time performance; in the VPN server at the receiving end, after the data packets transmitted through each sub-path arrive at the server, the tunnel protocol decapsulates, and then caches the data packets whose source address is the same VPN server. After requesting, it is sent to the decoding module for decoding, and continues to perform subsequent processing on the restored original data packet. In this way, fountain coding is performed before data packets enter the tunnel, and multi-channel parallel transmission is adopted, which can effectively improve transmission reliability, make full use of network resources, and increase network throughput. Fig. 6 is a schematic diagram of an overall structural model of a sending end and a receiving end provided by an embodiment of the present invention.

It should be noted that among the various components of the system of the present invention, the components are logically divided according to the functions to be realized, but the present invention is not limited thereto, and each component can be re-divided as required Or combined, for example, some components can be combined into a single component, or some components can be further broken down into more subcomponents.

The various component embodiments of the present invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art should understand that a microprocessor or a digital signal processor (DSP) may be used in practice to implement some or all functions of some or all components in the system according to the embodiments of the present invention. The present invention can also be implemented as an apparatus or an apparatus program (for example, a computer program and a computer program product) for performing a part or all of the methods described herein. Such a program for realizing the present invention may be stored on a computer-readable medium, or may be in the form of one or more signals. Such a signal may be downloaded from an Internet site, or provided on a carrier signal, or provided in any other form.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In a unit claim enumerating several means, several of these means can be embodied by one and the same item of hardware. The use of the words first, second, and third, etc. does not indicate any order. These words can be interpreted as names.

The above embodiments are only suitable for illustrating the present invention, rather than limiting the present invention. Those of ordinary skill in the relevant technical fields can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all Equivalent technical solutions also belong to the category of the present invention, and the scope of patent protection of the present invention should be defined by the claims.

Claims (10)

1. A multi-channel parallel transmission method based on fountain codes, characterized in that the method comprises: Obtaining the corresponding receiving end address according to the destination address of the original data packet to be sent, and buffering the original data packet to be sent in different queues according to the receiving end address; For each queue, determine whether the number of original data packets in the queue reaches a preset number or whether the waiting time of the original data packets in the queue exceeds a preset time; When judging that the number of original data packets in the queue reaches the preset number or the waiting time of the original data packets in the queue exceeds the preset time, performing fountain encoding on the original data packets cached in the queue respectively to obtain encoded data packets; Obtaining the overall status of multiple tunnels used to transmit the encoded data packets, and selecting a corresponding transmission mode according to the overall status, and in the corresponding transmission mode, according to the degree value of the encoded data packets, the encoding The data packet selects a corresponding tunnel, and adjusts its transmission mode correspondingly at different stages in the transmission process of the encoded data packet, so as to realize multiple parallel transmissions of the original data packet. 2. the multi-channel parallel transmission method based on the fountain code according to claim 1, wherein, before the destination address of the original data packet to be sent obtains the corresponding receiver address, the method also includes: According to the preset routing algorithm, multiple disjoint path sets between itself and any receiving end are obtained. 3. the multi-channel parallel transmission method based on fountain code according to claim 1, is characterized in that, described method also comprises: receiving the decoding information fed back by the receiving end for decoding the encoded data packet, and stopping the transmission of the encoded data packet when the receiving end has successfully decoded the original data packet according to the decoding information, and sending the next batch of Raw packets are processed and transmitted in the same way. 4. The multi-channel parallel transmission method based on fountain codes according to claim 1, wherein the corresponding transmission mode is selected according to the overall situation, and in the corresponding transmission mode, according to the encoded data packet Select the corresponding tunnel for the encoded data packet, and adjust its transmission mode accordingly at different stages in the transmission process of the encoded data packet, including: When it is judged according to the overall condition that the overall transmission performance of the multiple tunnels is good, Evaluate and classify the transmission quality of each tunnel according to the delay, bandwidth, arrival rate of each tunnel, and the correlation between tunnels, and obtain the priority order of multiple tunnels. Using the first encoded data packet whose priority is higher than the set value of the tunnel transmission degree value is lower than the preset value, and the priority is lower than the set value The second encoded data packet whose tunnel transmission degree value is higher than the preset value , When the number of transmissions of the first encoded data packets reaches the first preset number, transmit the second encoded data packets using a tunnel with a priority higher than the set value, and a priority lower than the set value tunneling of said first encoded data packet; In the case where the overall transmission performance of the plurality of tunnels is judged to be poor according to the overall condition, transmitting said first encoded data packet on all tunnels, When the number of transmissions of the first encoded data packets reaches a second preset number, the second encoded data packets are transmitted on all tunnels. 5. A multi-channel parallel transmission device based on fountain codes, characterized in that the device comprises: The first buffer module is used to obtain the corresponding receiving end address according to the destination address of the original data packet to be sent, and cache the original data packet to be sent in different queues according to the receiving end address; The first judging module is used for, for each queue, judging whether the number of original data packets in the queue reaches a preset number or whether the waiting time of the original data packets in the queue exceeds a preset time; The fountain code encoding module is used to perform fountain encoding on the original data packets cached in the queue respectively when the number of original data packets in the judging queue reaches a preset number or the waiting time of the original data packets in the queue exceeds a preset time, Get the encoded data packet; A packet scheduling module, configured to obtain the overall status of multiple tunnels used to transmit the encoded data packets, and select a corresponding transmission mode according to the overall status, and in the corresponding transmission mode, according to the overall status of the encoded data packets The degree value selects a corresponding tunnel for the encoded data packet, and adjusts its transmission mode correspondingly at different stages in the transmission process of the encoded data packet, so as to realize multiple parallel transmissions of the original data packet. 6. The multi-channel parallel transmission device based on fountain codes according to claim 5, wherein the device further comprises: The path management module is configured to calculate multiple disjoint path sets between itself and any receiving end according to a preset routing algorithm. 7. The multi-channel parallel transmission device based on fountain codes according to claim 5, wherein the packet scheduling module is also used for: receiving the decoding information fed back by the receiving end for decoding the encoded data packet, and stopping the transmission of the encoded data packet when the receiving end has successfully decoded the original data packet according to the decoding information, and sending the next batch of Raw packets are processed and transmitted in the same way. 8. The multi-channel parallel transmission device based on fountain codes according to claim 5, wherein the packet scheduling module is specifically used for: When it is judged according to the overall condition that the overall transmission performance of the multiple tunnels is good, Evaluate and classify the transmission quality of each tunnel according to the delay, bandwidth, arrival rate of each tunnel, and the correlation between tunnels, and obtain the priority order of multiple tunnels. Using the first encoded data packet whose priority is higher than the set value of the tunnel transmission degree value is lower than the preset value, and the priority is lower than the set value The second encoded data packet whose tunnel transmission degree value is higher than the preset value , When the number of transmissions of the first encoded data packets reaches the first preset number, transmit the second encoded data packets using a tunnel with a priority higher than the set value, and a priority lower than the set value tunneling of said first encoded data packet; In the case where the overall transmission performance of the plurality of tunnels is judged to be poor according to the overall condition, transmitting said first encoded data packet on all tunnels, When the number of transmissions of the first encoded data packets reaches a second preset number, the second encoded data packets are transmitted on all tunnels. 9. A multi-channel parallel transmission method based on fountain codes, characterized in that the method comprises: receiving multiple tunnel-transmitted data packets, decapsulating the data packets using a tunneling protocol, and filtering to obtain encoded data packets; respectively buffering the encoded data packets in different queues according to the source addresses of the encoded data packets; For each queue, determine whether the number of encoded data packets in the queue reaches the number required for decoding; When it is judged that the number of encoded data packets in the queue reaches the number required for decoding, fountain decoding is performed on the encoded data packets buffered in the queue to obtain original data packets, thereby realizing multi-channel parallel transmission of the original data packets. 10. the multi-channel parallel transmission method based on fountain code according to claim 9, is characterized in that, described method also comprises: Feedback decoding information to the sending end according to the decoding situation, so that the sending end stops transmitting the encoded data packets according to the decoding information, and performs the same processing and transmission on the next batch of original data packets.