Design of A Dynamic TCP Vegas to Support Long-distance High Speed Networks

• Main Authors: Bei-Hao Su, 蘇倍豪
• Other Authors: Mong-Fong Horng
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/86745475812843795082

碩士 === 樹德科技大學 === 資訊工程學系 === 96 === The main purpose of this research is to propose a new scheme to improve the throughput of long-distance TCP connections. The proposed scheme is a variation of TCP Vegas. Differing from the current standard TCP algorithms (TCP New Reno), the proposed scheme uses Round-Trip Time (RTT) to derive the actual throughput of the target connection. According to the difference between the actual throughput and the desired throughput, the congestion window size is adjusted to either speed op or slow down the TCP connection. For efficient response, the strategy of window-adjustment is composed four parts to meet the requirements of four stages of a TCP connection. We improve the constant-interval approach of TCP Vegas. In the new scheme, dynamic adjustment of TCP Vegas α, β value is designated to enhance the throughput of the standard TCP Vegas. Simulation results show that in various conditions of bandwidth and distance, the proposed scheme effectively improves the throughput of standard TCP Vegas. Besides, the analysis of fairness among homogenous and heterogenous TCP connections is also presented.