Statistical broadcast protocol design with WiBDAT: Wireless Broadcast design and analysis tool

Abstract

Multi-hop broadcast routing is a critical component in ad-hoc wireless networks. Vehicular ad-hoc network (VANET) applications for example use broadcast communications extensively. Efficient broadcast protocols are required to enable these applications. Multi-hop broadcast algorithms can roughly be classified as either topological or statistical. Statistical protocols are well-suited to applications such as VANET, because they are tolerant of rapid changes in network topology and can be designed to accommodate transmission failures due to fading and collisions. However, unlike topological protocols, statistical methods are highly stochastic in nature so it is not possible to analytically prove these algorithms will connect all nodes in the network. Instead, designers attempt to measure and minimize the probability nodes will not receive a broadcast message. Thus simulation plays an important role in the design and validation of these protocols. The key design factor in statistical protocols is the rebroadcast decision threshold curve. There are no analytical tools for creating these threshold curves, so like many stochastic systems, simulation models are required to develop them. Empirically discovering good threshold curves using simulation models requires many simulation iterations, and thus can be extremely time consuming if these iterations are slow. As a solution, this work introduces the Wireless Broadcast Design and Analysis Tool (WiBDAT), a fast and scalable high-level network simulator built from the ground up specifically for wireless broadcast. WiBDAT provides tools for quickly designing efficient statistical broadcasting protocols and evaluating their performance at a high level. WiBDAT is easy to use and extend, implements a wide variety of broadcast protocols, and provides clear results including innovative visualizations of node and transmit densities.