Research on TCP Protocol in Wireless Network and Network Simulation

With the increasing widespread use of wireless technologies, many improved TCP congestion control mechanisms used in wireless networks have been presented. Because TCP congestion control mechanism designed for fixed network are not applicable in wireless networks, we propose a modified TCP congestion control mechanism based on double windows for wireless networks in this paper. The modified mechanism divides the TCP congestion window into two parts: the dispose congestion window and the dispose error-code window. It considers the influences to TCP sender´s packet sending rate not only by the congestion but also by the corruption to decrease the energy consumption of mobile hosts. Simulation results show that the modified TCP congestion control mechanism can effectively improve the transmission reliability with small variances of throughput and delay.