Data retransmission method and device

Abstract

The invention, which relates to the communication field, provides a data retransmission method and device. The method comprises: after a real-time data packet is sent to a server, the real-time data packet carrying a packet serial number to a first cache region; and when response information that is returned by the server and corresponds to the packet serial number of the real-time data packet is not received within a first time threshold, the real-time data packet corresponding to the packet serial number in the first cache region is retransmitted to the server by a retransmission thread. In the prior art, the data transmission success can not be guaranteed and the packet loss probability is high according to the TCP protocol retransmission mechanism. However, according to the data retransmission method provided by the invention, a retransmission work mechanism asynchronous with the TCP transmission protocol is employed; and thus the response information for first-time data packet sending and receiving is in an asynchronous working process, so that next data can be sent without the need to wait for receiving the response information of the last data packet. Therefore, a phenomenon of data sending waiting caused by data packet and response information delay due to network congestion can be avoided, so that the real-time and rapid properties of data are enhanced.

Description

technical field [0001] The present invention relates to the technical field of communications, and in particular, to a data retransmission method and device. Background technique [0002] TCP (Transmission Control Protocol, Transmission Control Protocol) is a connection-oriented, reliable, byte stream-based transport layer communication protocol, defined by IETF's RFC 793, which is a standard for network communication. Currently, through the network Most of the transmitted data is transmitted based on the TCP protocol. [0003] In actual data transmission, usually there will be a large amount of real-time data that needs to be uploaded to the server by the wireless network using the TCP protocol. The transmitted real-time data ranges from several to dozens of pieces per second. After sending these data to the server, if the ACK message fed back by the server is not received within the predetermined time, the TCP timeout retransmission mechanism will be started, that is, the...

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Problems solved by technology

[0004] However, the existing TCP overtime retransmission mechanism has very short retransmission times and time. Once encountering GPRS (General Packet Radio Service, General Packet Radio Service), 3G (3rd-Generation, third-generation mobile communication technology) , 4G (the 4th Generation mobile communication technology, the fourth generation mobile communication technology) and other network congestion or poor signal conditions, there is a high probability that data will be lost for a few seconds or more than ten seconds, and the retransmission mechanism of TCP itself does not Guarantee the success of data transmission. After the preliminary test, relying on the retransmission mechanism of TCP itself has a packet loss rate of more than 20%.

And when the current network environment is bad, it is even more impossible to guarantee the accuracy of the data

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