Evaluating and Improving TCP Performance against Contention Losses in Multihop Ad Hoc Networks
نویسندگان
چکیده
Default TCP treats all losses as congestion since it was designed and optimized to work in networks with low noncongestion losses. In this paper first it is shown that the dominant cause of packet drops in multihop ad hoc network is medium access contention and congestion losses, are very rare. Then the most prevalent packet contention drops are analyzed and based on that a modification to both TCP and IEEE802.11 MAC is proposed and evaluated. It is also shown that this modification can eliminate TCP throughput instability which is regarded as one of main TCP problems in multihop networks. KeywordsContention drop, Hidden Terminal, IEEE802.11 MAC, Multihop Ad hoc Network, TCP
منابع مشابه
TCP Contention Control: A Cross Layer Approach to Improve TCP Performance in Multihop Ad Hoc Networks
It is well known that one of the critical sources of TCP poor performance in multihop ad hoc networks lies in the TCP window mechanism that controls the amount of traffic sent into the network. In this paper, we propose a novel cross layer solution called “TCP Contention Control” that dynamically adjusts the amount of outstanding data in the network based on the level of contention experienced ...
متن کاملA Cross Layer Solution to Address TCP Intra-flow Performance Degradation in Multihop Ad hoc Networks
Incorporating the concept of TCP end-to-end congestion control for wireless networks is one of the primary concerns in designing ad hoc networks since TCP was primarily designed and optimized based on the assumptions for wired networks. In this study, our interest lies on tackling the TCP instability and in particular intra-flow instability problem since due to the nature of applications in mul...
متن کاملLocal Route Recovery Algorithms for Improving Multihop TCP Performance in Ad Hoc Wireless Networks
TCP (transmission control protocol) will for sure continue to be the major transport protocol in wireless environments, due to its large install-base in existing applications. Indeed, in future ad hoc wireless networks where devices communicate among each other over multihop routes, TCP is expected to be the prominent protocol for data exchange (e.g., multihop wireless FTP). However, there is a...
متن کاملWireless Congestion Control Protocol For Multihop Ad Hoc Networks
The traditional TCP congestion control mechanism encounters a number of new problems and suffers a poor performance when the IEEE 802.11 MAC protocol is used in multihop ad hoc networks. Many of the problems result from medium contention at the MAC layer. In this paper, I first illustrate that severe medium contention and congestion are intimately coupled, and TCP’s congestion control algorithm...
متن کاملCOPAS: dynamic contention-balancing to enhance the performance of TCP over multi-hop wireless networks
Most studies on TCP over multi-hop wireless ad hoc networks have only addressed the issue of performance degradation due to temporarily broken routes, which results in TCP inability to distinguish between losses due to link failures or congestion. This problem tends to become more serious as network mobility increases. In this work, we tackle the equally important capture problem to which there...
متن کامل