PSSB: Priority enforced slow-start backoff algorithm for multimedia transmission in wireless ad-hoc networks

The binary exponential backoff (BEB) algorithm is the fundamental access method, which provides collision avoidance in wireless ad-hoc networks. However, BEB algorithm poses several performance issues. For example, the high collision rate problem, unfair channel access and throughput degradation have been several widely known issues. Besides, frames in BEB do not have priorities, making it unsuitable for multimedia communications. With a little bad luck, a station might have to wait arbitrarily long to send a frame. In this paper, we introduce the priority enforced slow-start backoff algorithm (PSSB) for multimedia transmission for wireless ad-hoc networks, which employs a distributed adaptive contention window control mechanism to mitigate intensive collisions in congested scenario and support priority traffic for multimedia transmission. Furthermore, the proposed scheme could alleviate the fairness problem in partially connected network topology by employing feedback information from wireless stations. Simulations are conducted to evaluate the performance of the proposed scheme. The results show that the proposed scheme outperforms the BEB algorithm in many aspects in wireless ad hoc networks. (C) 2010 Elsevier Ltd. All rights reserved.