Article details

Title: TCP WR: Simulation Based Comparison with Major TCP Versions
Author(s): Mohammad-Ariful Huq               

Abstract: In this paper, we proposed a new version of a TCP protocol, called TCP WR, which enhances the performance of TCP Westwood+ by measuring the available bandwidth from the receiver’s end. TCP performance over wireless network is giving degraded performance due to its inability to differentiate between wireless loss and congestion loss. TCP Westwood+ is a recently proposed protocol which has ability to differentiate between these two losses. This paper, first, analyzes TCP Westwood+ and, then, proposes a new scheme for its bandwidth (BW) measurement. Generally, TCP Westwood+ estimates BW from the sender side by measuring the returning rate of acknowledgments (ACKs). Here, we are proposing a new technique for bandwidth estimation which will use Timestamp-Based Available Bandwidth estimation (TABE) algorithm for estimating BW. TABE is a TCP-sender-side algorithm that continuously estimates the bandwidth available to the connection and guides the sender to adjust its transmission rate when the network becomes congested. Simulation results will show that TCP WR can achieve better throughput than the existing protocols like New Reno, Westwood+, Vegas and New Jersey.

Keywords: TCP Westwood+, bandwidth estimate, congestion control, performance comparison.

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