Improving TCP-Vegas Performance Over MANET Routing Protocols

Recently, the Internet Engineering Task Force Mobile Ad Hoc Network (MANET) working group has standardized the reactive and proactive MANET routing protocols. In addition, work on using the transmission control protocol (TCP) to provide reliable data transmission has been performed for the purpose of smooth integration with the wired Internet. In the wired Internet, TCP-Vegas is a well-known transport protocol which takes into account existing network conditions. However, TCP-Vegas cannot be directly applied to MANETs because a route change (RC) can make the BaseRTT used over a previous path obsolete. Hence, the authors propose their TCP-Vegas-ad hoc protocol, which is made aware of RCs and uses the correct BaseRTT values. Through simulations using ns-2, it was observed that the TCP-Vegas-ad hoc outperforms the standard TCP-Vegas protocol, especially under high mobility scenarios over both reactive and proactive ad hoc routing protocols