A Divide and Conquer Technique for the Contention Window to improve the QoS of MAC

Efficient Quality of Service (QoS) has become new challenge in Wireless Local Area Networks (WLANs). Voice over Internet Protocol (VoIP) is an important service with strict quality of requirements in Wireless Local Area Network (WLANs). The IEEE802.11e introduced a contention window based technique that is Enhanced Distribution Channel Access (EDCA) that provides a prioritized traffic to guarantee minimum bandwidth needed for time critical applications, through modifications to the medium access control layer. The number of nodes in the network are less the performance of this technique is good, if the number of nodes has increased randomly, the Static behavior of EDCA will show the effect on network usage by increasing the congestion level leads to packet loss in the networks, which intern leads to bad performance and poor link utilization whenever the demand for link utilization increases. Availability of techniques IEEE802.11a and IEEE802.11e proposed new adaptive differentiation techniques for resetting the value of contention window to improve the quality of service. In this paper we proposed a Novel frame work by setting the contention window based on the Divide and Conquer strategy which in turn leads to efficient Quality of Service (QoS) by reducing the channel congestion level even if we have more number of nodes in the network and also reducing the packet loss and packet delay in Wireless Local Area Networks.