A mechanism to enforce TCP Fairness in 802.11 wireless LANs and its performance evaluation in a real test-bed

In this paper, we study the problem of maintaining fairness for TCP connections in wireless local area networks (WLANs), based upon the IEEE 802.11 standard and operating in DCF mode. Although this mode of operation ensures fair access to the medium at the MAC level, it does not provide fairness among TCP connections. TCP unfairness may result in significant degradation of performance, leading to users perceiving unsatisfactory quality of service. We propose and analyze a solution capable of enabling TCP fairness with minimal additional complexity. The proposed solution is based on utilizing an IP rate-limiter with an adaptive rate control mechanism and does not require modifying existing standards at the MAC or network layers. The solution is fully compatible with existing devices and can be integrated either within the access point or within and external device (e.g., the network gateway). The performance analysis is performed in a real test-bed and proves the feasibility and effectiveness of our mechanism. To allow fellow researchers to reproduce our work we published on the WEB all the implementation code.