Improving The Performance Of Tcp In A Gprs Channel

With the Internet more and more popular, the data services(Email ,FTP, web browsing) over Internet increase dramatically. The General Packet Radio Service (GPRS) is part of the new generation of mobile phones offering an always-on, packet based system for Internet connection, with significantly higher bandwidth than is currently available with older mobile phone networks. GPRS, however, has its limitations. Current implementations allow connection to the GPRS Internet at rates of around 40Kbps - around four times faster than GSM. In practice, the experience is much slower than this suggests.There are many reasons to be GPRS network data transmitting bottlenecks, TCP is one of them. Our aim is to improve TCP performance over GPRS networks.In the first chapter, we propose the emergency to accelerate the GPRS network, introduce the knowledge about GPRS, including architecture, protocol, signal.The second chapter focuses on TCP and why GPRS characteristics do not interact well with current TCP implementations. We present the results of a series of experiments used to characterize the performance of a GPRS.In the third chapter, we show a proxy interposed the fixed and GPRS networks, over which we employ our own wireless TCP protocols. The protocols are WECN, LT, PACING. These protocols performance are valued in a emulated GPRS network.The fourth chapter realizes SNOOP TCP in Linux Kernel, some changes are added according to GPRS link characteristics. The last chapter, we realize T/TCP (transaction transmission control protocol) in Linux which eliminates the round trips involved in connection setup in normal operation. Both the SNOOP TCP and T/TCP, we test their performance in a emulated GPRS network and analyze them.