Virtual Backoff Algorithm: An Enhancement to 802.11 Medium-Access Control to Improve the Performance of Wireless Networks

This paper presents a scheme, called the virtual backoff algorithm (VBA), which is based on the sequencing technique for efficient medium-access control. The proposed method minimizes the number of collisions while reducing the delays that occur during the backoff periods. We present an analytical study on MAC-layer issues, which are very important when accessing a channel over wireless networks. The VBA scheme uses fair distributed mechanisms to access a channel. We introduce a counter at each node to maintain the discipline of the nodes. The performance of the proposed method is evaluated under various conditions, and the obtained results are very promising. The enhanced protocol improves the utilization of bandwidth by increasing the throughput up to 75%, and the amount of collisions is reduced to 65% when compared with legacy protocols. The proposed scheme shows that the energy requirements are minimum due to the limitation on the number of transmissions.