PRIORITY DRIVEN STRP: AN EFFICIENT POLLING MAC PROTOCOL FOR WIRELESS LANs

Abstract

The performance of wireless local area. networks (LANs) depends, to a large extent, on the availability of flexible and efficient medium access control protocols that cope with the constraints imposed by the wireless propagation environment. For wireless LANs, Polling schemes are an important class of medium access control (MAC) protocols. A major drawback of these schemes is their inefficiency when only a small number of mobile stations have packets to transmit. This inefficiency.is due to the polling of mobile stations with no packet to transmit, which delay the transmission of mobile stations with packets. In such a scenario, it is required to have a MAC layer protocol to utilize the limited available bandwidth efficiently. In the dissertation Simultaneous transmit response polling (STRP), a MAC protocol has been analyzed. STRP exploits the capture phenomenon and enables the simultaneous polling and transmission of information packets. The dissertation work also presents some improvements to the protocol so that it could be able to provide priority to more important traffic. While scheduling the stations the improved protocol, Priority Driven STRP (PSTRP) considers the type of traffic that each station is sending and hence gives each of the station a priority over the other based upon the type of traffic. At the same time the normal traffic is not ignored. The simulation is done in C++ programming language in windows 98 environment in order to compare the performance of the Simple Polling (U-Poll) and PSTRP