Research On Packet Loss Measurement For Reliable Transport Protocol Based On UDP

With the rapid development of Internet transport protocol,the TCP / IP protocol architecture is facing a bottleneck.The upper layer protocol based on UDP protocol have more and more advantages and extensive applications.In the field of network measurement,the existing methods mainly solve the problem of packet loss measurement under TCP transmission,and there are also some methods to measure packet loss for specific protocols.The research of packet loss measurement for new reliable transport protocols based on UDP is very few,and there is a lack of effective method to detect packet loss of various reliable transport protocols based on UDP in the transmission intermediate node.Therefore,the research on packet loss measurement of reliable transport protocol based on UDP is of great significance.In view of the above problems,this paper studies the reliable transmission mechanism of reliable transmission protocol based on UDP,and proposes a packet loss measurement method based on the classification detection of positive and negative response of return data and protocol format reversing engineering.The two methods use deep packet detection technology and deep flow detection technology respectively,which can accurately measure packet loss in multiple reliable transmission protocols based on UDP.The main contributions and innovations of this paper are as follows:(1)Aiming at the simple design of UDP protocol and the fact that the header field of UDP packet only contains four information: source port,destination port,length,check and so on,it is very difficult to measure the packet loss of UDP protocol.A packet loss measurement method based on classification detection of positive and negative responses of returned data is proposed.We use a packet loss detection function as a model to detect packet loss.The packet loss detection function is composed of two sub functions,which are used to measure the fluctuation of the positive response signal of the returned data stream and to count the packet loss information carried by the negative response in the returned data stream.This method has the advantages of small implementation cost,fast processing speed,and is not affected by the encryption mechanism of the protocol.It has a good detection effect on the protocol using positive and negative response messages to achieve reliable transmission.(2)To solve the problem that it is difficult to identify and detect the positive and negative response messages in private or certain public protocols,a packet loss measurement method based on protocol format reverse analysis is proposed.This method uses protocol reversing engineering technology,infers the set of protocol field features for packet loss detection through sequence alignment algorithm,selects the optimal rules through the evaluation function,and dynamically and adaptively uses the previously inferred protocol field features through the pre implemented detection method to realize packet loss detection.This method has strong practicability,high measurement accuracy,stable detection effect,and is not affected by the upper service.It has good detection ability for a variety of public and private protocols.(3)In order to solve the problem that it is difficult for a single stream feature oriented or packet feature oriented method to have the ability to measure a variety of protocols with different mechanisms and implementations,this paper implements a prototype system of composite packet loss measurement method integrating the above two packet loss measurement methods.The system can transfer sample data to build and integrate packet loss detection components,and output visual detection results of sample data to be detected,which has strong practicability and scalability.