A Probabilistic Protocol for Multi-Hop Routing in VANETs

Vehicular ad hoc networks (VANETs) allow communications over sequences of vehicles with radio devices. On such a network, there are many possible applications such as traffic jam warning, collision warning, parking lot reservations, camera picture feed etc. There have been quite a few results in the area seeking for a fast and reliable communication protocol due to their potential. VANETs, however, are pointed out as difficult for numerical optimizations due to frequent changes in their topologies. As a result, heuristic methods such as GPSR have been mainly used for routing packets over multi-hop communications. In this paper, we present an algorithm to pre-compute the probability that the communication is possible between specified source and destination in a VANET, under certain mathematical assumption. The proposed new protocol for multi-hop communication refers to a lookup table containing the pre-computed data to decide a good packet forwarder quickly. We create a simulation testbed that seems challenging for all the existing multi-hop routing protocols for VANETs, in which we test ours. We see much improved performances over GPSR after the algorithm is refined for some practical issues.