Methods for restoring MAC layer fairness in IEEE 802.11 networks with physical layer capture

In this paper, we experimentally investigate the physical layer capture effect in off-the-shelf 802.11 network cards and confirm that it reduces throughput fairness of traffic flows. We then study the feasibility of using the following PHY and MAC layer approaches to mitigate the disproportionate allocation of throughput in capture dominated scenarios: transmit power control, retransmission lim-its, CWmin adjustment, TxOp adjustment, and AIFS control. The results obtained on the ORBIT indoor wireless testbed 1 show that the 802.11e EDCF parameters provide the most fine-grained con-trol of fairness.