Improving broadcast efficiency of irresponsible forwarding with random linear coding at source

Broadcasting is the most prevalent method for disseminating information in vehicular networks. At high vehicle densities, the so-called broadcast storm problem degrades the efficiency of broadcasting. A so-called Irresponsible Forwarding (IF) scheme has recently been proposed in the literature that can effectively combat the broadcast storm problem. For messages consisting of multiple packets, the coupon collector problem also degrades the broadcast efficiency at all vehicle densities. In this paper, we extend the basic IF scheme to multi-packet messages, which we call the max-min IF, and combine it with Random Linear Coding (RLC) of packets at the source to solve the coupon collector problem and improve the broadcast efficiency of IF. Through discrete event simulations, with a widely accepted realistic vehicular mobility model based on cellular automata, we demonstrate that our IF+RLC scheme can significantly improve the reachability in sparsely connected vehicular networks at low vehicle densities as well as reduce the mean delay under high probability of collisions at high vehicle densities.