Research On Improvement Of TCP Protocol In Mobile Wireless Network

The wireless network is playing an increasingly important role on human's life, work and study, which generates many of the relevant research subjects, the improvement of the tcp protocol is one of the most important subjects. In recent years, there are some results about the research of the tcp protocol in the wireless network, and some classical improve algorithms are generated. As the network service quality call for higher, the tcp protocol wireless network of research is still significant.This article first introduced the tcp protocol of data transmission mechanisms and congestion control mechanism and wireless tcp congestion control algorithm development and hot research aspect.And then analyze the performance of TCP protocol on the wireless network. The major factors of the decline performance of tcp in mobile wireless network are summarized, including:high bie error rate, error detection mechanisms of packet loss, wireless link bandwidth limitied, link break, routing, asymmetry of bandwidth, link layer delay. Then some of the classic improvemal strategies of current wireless TCP research fields are studied, including:end-to-end TCP technology, subsection TCP technology, the date link layer technique.On this basis, we will analyze introduce the WTCP scheme.There are deficiencies of WTCP protocol in the error control mechanism in the mobile wireless network.Based on this,a new solution is put forward combined with the link to Freeze of TCP-Freeze protocol.The new protocol of NWTCP is aiming at improving the mobile wireless network transmission performance. There are two main innovations of NWTCP protocol:1, Through the ACK state information returning from the mobile terminal, the sender reduces or delays sending data, in order to reduce the reaction number of mobile terminal, then save energy;2, For the frequent handoff of mobile wireless network, when the link is cut, there is not slow start of the send, but freezing. Once the link is recovery, then to send date at original windows, which can improve the network throughput.In the paper, network simulation tool ns2 is used for emulation. First, the NWTCP protocol is compared with wtcp protocol and TCP NewReno protocol, which have been proved outperformed in the espect of throughput. Then the NWTCP protocol is compared with the TCP NewReno and the WTCP in the aspect of the use of energy efficiency and productivity in the wireless network. There is obvious improvement in efficiency shown by the results.Last reviewed in all work, according to the agreement of theory and practical simulation results, the relevant conclusion is provided. The later looking forward to the working is inroduced.