• Summary
• Related Documents
  • Active Bibliography
  • Co-citation
• Version History

Abstract:

Since 1988, when the congestion control functions were first introduced, the performance of TCP has been greatly improved. However, TCP still suffers large performance degradation over wireless links due to characteristics specific to wireless environment that affect the behavior of TCP's congestion control and avoidance mechanisms. These mechanisms were designed and optimized for traditional wireline networks where packet losses are predominantly due to network congestion. In wireless networks, packet losses are mainly caused by the high bit error rate (BER) and hand-offs. Since TCP cannot differentiate packet losses caused by congestion from losses introduced by the wireless links, its performance degrades. M-TCP is a solution proposed to address the problems of TCP over wireless links with periodic disconnections. In this paper, we first give a brief introduction to M-TCP protocol. We then describe the OPNET implementation of M-TCP and the simulation scenarios in a mixed wireline/wireless environment. We give performance comparisons between M-TCP and TCP with and without presence of frequent disconnections in wireless links. Simulation results indicate that in the presence of frequent disconnections M-TCP outperforms TCP in terms of maintaining congestion window size, goodput, and sender size retransmission timer.

Citations