A Scheme to Eliminate Redundant Rebroadcast and Reduce Transmission Delay Using Binary Exponential Algorithm in Ad-Hoc Wireless Networks

Abstract

Ad-hoc wireless network is a Collection of wireless mobile nodes dynamically forming a temporary network without the use of any existing network infrastructure or centralized administration. Neighbor discovery is an important part of many protocols for wireless adhoc networks, including localization and routing. When neighbor discovery fails, communications and protocols performance deteriorate. Broadcasting is a common operation in a network to resolve many issues. In a mobile ad hoc network (MANET) in particular, due to host mobility, such operations are expected to be executed more frequently such as finding a route to a particular host, paging a particular host. Probabilistic broadcasting is best suited in terms of ad hoc network which is well known for its decentralized network nature and Binary exponential Back off (BEB) algorithm stated in the 802.11 standard plays an important role in the distributed coordinate function (DCF), which is provided at the medium access control (MAC) layer of the IEEE 802.11 standard. BEB might introduce long transmission delays without any significant benefit in respect of contention resolution due to node mobility. In fact, contending mobiles are likely to move to a different location during a large waiting time for retransmission after a packet collision and might get involved into another independent collision process elsewhere. Thus, the large growth rate in waiting time might not be appropriate in a mobile scenario as in a WLAN. Bearing this in mind, we propose certain modifications to BEB algorithm suitable for WLANs.