Improving Research Of TCP Vegas In Satellite Networks

With the rapid development of the communication network, more and more peoplealso gradually improve to the requirement of space network and focus on the satellitenetwork with its unique networking advantages. For satellite communication networkhas the advantages of wide coverage, high transmission which will make the satellitenetwork communication technology become an important research direction in future.However, the features of satellite networks such as large propagation delay, linkasymmetry and high bit error rates which impact the performance of the TCP protocolof terrestrial networks by using in satellite network. So how to enhance TCPperformance over the satellite based Internet is an important research topic.In this paper, we study how to improve performance of TCP in satellite network,and probe into the particularity of satellite link which effects on the TCP protocol, thenput forward the concrete solution to optimize TCP protocol. Comprehensive abovescheme we propose a relatively stable TCP Vegas protocol, through the optimization ofTCP Vegas mechanism, making it more suitable for data transmission in satellitenetworks.According to the characteristics of satellite networks, the TCP protocol on theground is improved to make it more suitable for the satellite network for datatransmission. Mainly improvement program with TCP Vegas：Firstly improve the TCPcongestion control mechanism of TCP Vegas and then adaptive adjustment of the size ofthe send window by the changes of network traffic. Second, according to the high errorrate characteristics of satellite network, to provide Loss Differentiation Algorithms,adjusting the data packet transmission rate of the satellite network. Finally, according tosatellite network asymmetrical feature, the application of the TCP protocol selectednegative acknowledgment (SNACK) option.to recover the lost packet Under keep congestion window size conditions. but also can reduce the reverse link responsepacket congestion problems. This paper uses NS2to simulation, comparing andanalyzing with the traditional TCP.