Collision probability based Available Bandwidth estimation in Mobile Ad Hoc Networks

Abstract

Ever increasing demand for streaming applications transfer data in real-time over Mobile Ad hoc NETworks (MANETs). These transmission estimates Available Bandwidth (ABW) at each node before transmission in MANETs as channel is shared. The ABW mainly depends on the channel utilization which can be improved by minimizing packet losses. Researchers proposed many techniques to minimize the packet losses by developing models for synchronized idle period at sender-receiver pair before data transfer, collision probability and random waiting. In this paper, we propose a scheme of estimating ABW in MANETs using similar but modified models. The idle period synchronization model of previous work uses parameters of various node state for actual workload, channel utilization at optimal workload and collision rate at optimal workload instead of actual. We use the actual channel utilization and collision rate. The collision probability model of previous work uses same Lagrange Interpolation polynomial irrespective of node behavior. We compute separate Lagrange Interpolation polynomial at each node according to node behavior dynamically. The random waiting time calculated in previous work does not consider all waiting time statistics which is added in our model of random waiting time calculation. The ABW estimated by our scheme is approximately 19.99% more accurate compare to the recent work done by other researchers. As we are computing Lagrange Interpolation polynomial at each node dynamically, evidently it adds computation overhead which is ignored as our goal is towards accuracy of ABW but optimized for speed in future.