PigWin: Meaningful Load Estimation in IEEE 802.11 Based Wireless LANs

In this paper, we propose a novel definition of the term load, which overcomes the weaknesses of traditional metrics for measuring load. We then present PigWin, which is a load estimation technique for IEEE 802.11 based Wireless Local Area Networks (WLANs) operating in the infrastructure mode. PigWin can also be applied to modified versions of the 802.11 MAC, such as Exponential Increase Exponential Decrease (EIED). PigWin performs the actual load estimation through analysis of the contention window size, which was used for every recent and successful uplink frame transmission. Through simulations using ns-2, we demonstrate the efficacy of PigWin, when applied to both the legacy 802.11 MAC and EIED. We also show how our definition of load helps us to obtain more meaningful load estimates.