Dynamic route diversion in vehicular networks

In vehicular ad hoc networks in a city environment, communication connections need to adapt to fast moving nodes (e.g., vehicles on streets) and large obstacles (e.g., office buildings). Fast moving nodes results in frequent topology changes. Large buildings surrounded by relative narrow streets allow only a short window of communication among nodes. Early solutions address this fundamental requirement by employing techniques that can reconnect a broken link quickly with low overhead. This strategy, however, cannot cope with a high frequency of broken links in a vehicular environment. To address this problem, a few connectionless-oriented techniques, e.g., connectionless approach for vehicular networks, have emerged. These schemes rely on any mobile host along the general direction towards the destination node to help forward the data packets. Extensive simulation results have shown that these methods are more robust, and perform significantly better than connection-oriented techniques. The current connectionless method, however, may suffer from packet drops since traffic congestion is not considered in the packet forwarding policy. We address this weakness, in this paper, by adapt the connectionless approach for vehicular networks with collision avoidance routing technique; and give simulation results, based on GloMoSim, to illustrate their performance advantage.