Analysis of a polling protocol for packet voice transport over IEEE 802.11 wireless LANs

In this paper we first give an overview of an isochronous coordination function (ICF) for supporting voice services over IEEE 802.11 wireless local area networks (WLANs). By emulating a dynamic TDMA-like service, ICF can reduce polling overhead while minimizing consecutive packet losses. Next we present a Markov model to analyze the average reconnection failure ratio, average packet loss ratio, and average goodput of the ICF method under three different reconnection schemes. In particular close form solutions are obtained. The model can also be extended to analyze other polling-based protocols. Therefore it provides a valuable insight into the design of polling-based protocols for supporting isochronous voice traffic over WLANs.