A Method for Estimating Access Delay Distribution in IEEE 802.11 Networks

The volume of multimedia traffic over wireless networks has been steadily increasing over the past decade. Unlike web browsing applications, multimedia data needs to satisfy stringent delay requirements since late packets are as good as lost packets. In this paper, we present a framework for the nodes in 802.11 networks to estimate the distribution of uplink access delay in Distributed Coordination Function (DCF) MAC mechanism using locally available information. The access delay for a packet is defined as the time between the packet arriving at the head of line of MAC queue, and its ACK being received. In our proposed framework, each node periodically records channel occupancy information to estimate the distribution of access delay. We use NS-2 simulations to verify the accuracy of our proposed approach.