Nima Afraz - Faculty of Computer and IT Engineering Qazvin Branch, Islamic Azad University Qazvin, Iran
Morteza Analoui - School of Computer Engineering Iran University of Science and Technology Tehran, Iran

While the demand for bandwidth increases exponentially with the growing number of internet based devices, traditional TCP algorithms are turning to be sub optimal. Delay-based congestion control algorithms which are designed to overcome this challenge, are proven to be more satisfactory than loss-based congestion algorithms. On the one hand, Loss base congestion detection technique depends solely on packet loss. On the other hand delay-based algorithms have the advantage of proactively detecting congestion occurrences based on packet delays and as a result avoiding unnecessary packet loss. TCP-Vegas as the most referred variant of delay-based algorithms is promised to achieve between 40 and 70 percent better throughput. However there is some problems which are preventing TCP-Vegas to become widespread. One of these problems is lack of fairness in bandwidth allocation while delay and loss-based connection share a link. In this paper we made some modifications on the original TCP-Vegas which enabled the new algorithm to compete fairly with loss-based algorithm.

TCP; Congestion control; internet protocol; delay-based congestion control