Improving Throughput in Wireless Local Area Networks

Imam AL-WAZEDI, Anjali AGARWAL, Ahmed K. ELHAKEEM

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Concordia University, Montreal, Quebec, Canada.

DOI: 10.4236/ijcns.2008.14038                

Abstract

The medium access control (MAC) technique of standard WLANs, called the distributed coordination function (DCF), is carrier sense multiple access based on collision avoidance (CSMA/CA) scheme with binary slotted exponential backoff. It has a two way handshaking technique for packet transmission and also defines an additional four way handshaking technique called RTS/CTS mechanism, which is used to reduce the hidden terminal problem. The RTS/CTS frames carry the information of the packet length to be transmitted which can be read by any listening stations, to update a network allocation vector (NAV) about the information of the period of time in which the channel is busy. In this paper a method is proposed called the table driven technique (which has two parts called table driven DCF and table driven RTS/CTS) which is similar to the standard DCF (IEEE802.11) and RTS/CTS (IEEE802.11) system without having the exponential backoff. In this technique users use the optimum transmission probability by estimating the number of stations from the traffic conditions in a sliding window fashion one period at a time, thereby increasing the throughput compared to the standard DCF (IEEE802.11) and RTS/CTS (IEEE802.11) mechanism while maintaining the same fairness and the delay performance.

Keywords

Standard DCF (IEEE802.11), Standard RTS/CTS (IEEE802.11), Table Driven DCF, Table Driven RTS/CTS

Conflicts of Interest

The authors declare no conflicts of interest.

References