RANDOM CHANNEL ACCESS IN IEEE 802.11 DCF Ad Hoc NETWORK USING GAME THEORY

Abstract

In the IEEE 802.11 based wireless ad hoc network the channel access is random. The nodes are accessing the shared channel independently. This accessing of channel by a user, influence the channel access of the neighbouring users. Standard 802.11 DCF network uses CSMA/CA protocol and employ a binary exponential back-off algorithm. This algorithm causes fairness problem. In this network when selfish users exists then they can access the channel for their own benefit. In such scenario game theory has been used to accomplish the selfish behaviour of the users. So I have proposed a game model for this IEEE 802.11 DCF based network in order to increase the overall network performance. In this game model user are accessing the channel according to their channel access probability. This channel access probability is decided on the basis of the data frame length and the delaying factor which is function of contention window. This game model solves the fairness problem and employs a mixed strategy Nash equilibrium. Finally the simulation result shows the game theory is best suited for such type of ad hoc network.