A Study Of Congestion Control Algorithm Of High Speed TCP And Its Implementation On Terabit Router

The main task of TCP protocol is to provide the reliable date stream communication service among the applied programs, namely the reliable data communication from port to port. However, with the development of network, the traditional TCP protocol especially its congestion control arithmetic has represented the capability shortage. Therefore it is necessarily to deeply research the TCP protocol and improve the congestion control arithmetic.Combining with the National High-Tech Research and Development Program of China (863 Program) for the Tenth-Five-year Plan"The basic platform and experiment system for Terabit scalable high performance IPv4/IPv6 routers", this paper makes research on a new congestion control arithmetic of TCP protocol—High Speed TCP, analyzing and aiming at Terabit Router to make an improvement and optimizing, proposing an improved arithmetic—SF-HSTCP (A more Stable and Fair High Speed TCP) , and making the test and evaluation to its capability.The main tasks of this paper:1. In the beginning, analyze the reason of producing congestion in network, then described the congestion control algorithm of traditional TCP protocol. And analyze the evaluation method of TCP congestion control algorithm. It provide the basis for the evaluation of algorithm.Take a detailed research on High Speed TCP congestion control algorithm, analyze the advantages of High Speed TCP compared with traditional TCP.2. We compare the capabilities of two TCP congestion control algorithm by simulation environment, we find out some limitations of High Speed TCP in its performance. It makes a fine foundation for improving the algorithms.3. Refer to an improved High Speed TCP congestion control algorithm—SF-HSTCP; this new algorithm improves manner of Increasing or Decreasing congestion windows of High Speed TCP. The paper tests the capabilities of algorithm—SF-HSTCP by simulation environment, its result proves that the improved algorithm enhances the convergence , stability and fairness of High Speed TCP congestion control algorithm and the improved algorithm reduces loss rate of High Speed TCP congestion control algorithm. All of these advantages make it be used in the intercom of Terabit Router.4. Take the SF-HSTCP congestion control algorithm be used in the intercom of Terabit Router. Based on the design principles of congestion control algorithm and the system structure of Terabit Router, we rise up a precept that use SF-HSTCP on Terabit Router from the angle of the system design. At last,testing the performance of algorithm in Terabit Router, the result of testing achieve the standard of 863 Program.