Research On TCP Veno Enhanced Congestion Control Algorithm And Implementation In Linux Network Test Bed

Since the advantages of convenient and mobility, wireless networks have beenwidely used. But wireless network usually has higher bit error rate, lower bandwidth,longer delay, and higher frequency of mobile switching, which leading to the poorreliability of the wireless link, and thus the network congestion is no longer the onlycause for the loss of data transmission resulting in a wireless network environment.The transmission loss caused by the poor reliability of wireless link doesn’t needto take congestion control and reduce the send rate. The TCP (Transmission ControlProtocol) just needs to retransmit the lost data. But when there is transmission loss, asthe traditional TCP can’t distinguish the reason for the transmission loss, it will takecongestion control blindly and reduce the send rate. So that makes the performance ofTCP significantly decreased in the wireless network environment. Thus, how toimprove the performance of the TCP in wireless networks has become a hot topic ofcurrent research.First, this article summarizes and analyzes several typical types of the wirelessnetworks and the problems faced by the traditional TCP in the wireless network andthe current research progress that focus on how to improve the performance of theTCP in the wireless network.Second, this article analyzes the mechanisms and existing problems of TCP Venoalgorithm, and proposes a novel end-to-end congestion control algorithm called TCPEveno, according to the existing problems of TCP Veno. The TCP Eveno improves thecongestion status differentiation mechanism and congestion control mechanism, inorder to distinguish the cause of transmission loss more accurately, and achieveshigher network resources utilization.Then, this article uses the network simulation software NS-2to evaluate the TCPEveno algorithm with a series of experiments. The experimental results conclude thatthe TCP Eveno algorithm proposed in this article can distinguish the causes for thetransmission loss more effectively, and adopt a more rational control strategy to obtainfuller bandwidth utilization while maintaining a good TCP-friendly with the traditional TCP algorithm.Finally, this article expands the existing Linux network test bed in the laboratorywith the expansion of the wireless LAN, and implements Eveno algorithm in theLinux system as a kernel module. The results of comparative experiments with Renoand Veno algorithm confirm that the TCP Eveno algorithm has been implementedsuccessfully in the Linux network test bed.The main innovations of this article are the followings:(1) Proposes a novel end-to-end congestion control algorithm called TCP Evenoalgorithm to improve the congestion status differentiation mechanism and congestioncontrol mechanism of TCP Veno algorithm.(2) Expand the existing network test bed with the expansion of the wireless LAN,and implement TCP Eveno algorithm successfully in the Linux network test bed.The TCP Eveno algorithm not only can achieve a higher link bandwidthutilization and maintain a good TCP-friendly, but also convenient for use. It modifiesonly the sender-side protocol without changing the router or the receiver-side protocolstack. It has the potential to be applied to the actual network environment.