Enhancing TCP RAPID using IGI

Several Transmission Control Protocols have been proposed to address the significant problem on congestion control avoidance in order to be efficient in achieving high throughput on high-speed network in non-intrusive manner. TCP RAPID has recently been proposed as a new TCP that can search and adapt to the available bandwidth within a few RTT. RAPID is an outstanding protocol in many aspects especially rapidly search for dynamic available bandwidth, queue friendliness, and fairness. The bandwidth estimation technique used in RAPID is based on queuing delay. The delay based protocol maintains high speed in bandwidth estimation and in non-intrusive manner. However, we found that RAPID cannot co-exist with other loss based protocols such as NewReno, which is commonly-used TCP version on the Internet. In this paper, we propose a solution to address this problem for TCP RAPID that is to derive the Initial Gap Increasing (IGI) algorithm to increase the stability of TCP RAPID. This can cause TCP RAPID to survive in the aggressive environment as it is in the today Internet.