TCP Congestion Control Algorithm And The Quality Evaluation

With the development of new network technology, especially the appearance of the High Bandwidth-Big-Delay-Product Network, the existing congestion control mechanism can not satisfy the need of new Internet. So, more and more scientists begin the research of this field and make it become a hot research field.There are two primary components in end-to-end congestion control:one is the link algorithm executed by network devices, such as routers orswitches; the other is the source algorithm executed by host computers or edge devices.We analysis the congestion control mechanism and stability of FAST TCP which is a new TCP congestion control protocol for high-speed long latency networks. It changes the congestion control mechaniam of traditional TCP esstntially.We improve FAST-TCP congestion control algorithm on fast recovery and congestion avoid and solve the persistent congestion. Efficiency, fairness, stability, convergence and friendly are most important criterions to measure congestion control mechanism.Althoughvarious excellent algorithmas have been presented, there has been no standard to evaluate quality of these algorithms. It is a big challenge for researchers to construct the TCP quality evaluation architecture and improve the TCP congestion control algorithms. Research on the TCP congestion control algorithm and its quality evaluation is discussed in this thesis.