QoS provided by the IEEE 802.11 wireless LAN to advanced data applications: a simulation analysis

IEEE 802.11 is a Media Access Control (MAC) protocol which has been standardized by IEEE for Wireless Local Area Networks (WLANs). The IEEE 802.11 MAC protocol offers two types of services to its users: synchronous and asynchronous. This paper presents an in-depth analysis, by simulation, of the asynchronous part alone. The analysis is performed by considering station data traffic patterns (hereafter advanced data traffic) which have a very similar shape to traffic generated by WWW applications. We carried out the simulation by taking into consideration two classes of scenarios: balanced and unbalanced. In the former class each station has the same offered load while in the latter class a specific station is more loaded than the others. Our conclusion is that the IEEE 802.11 MAC protocol performs satisfactorily for both classes of scenarios, although performance measures with advanced traffic are worse than the corresponding performance measures with Poissonian traffic. Furthermore, we broadened our analysis to include higher medium capacities than those planned (i.e., 1 and 2 Mbit/sec) up to 10 Mbit/sec. This part of the analysis shows that the IEEE 802.11 MAC protocol is not adequate to work at speeds planned for the forthcoming ATM Wireless LAN.