MAC for ad-hoc inter-vehicle network: services and performance

In this paper we analyze the performance of ADHOC MAC, a new MAC protocol proposed within CarTALK200, a European research project with the purpose to design novel solutions for inter-vehicle communications. ADHOC MAC has been devised to provide a reliable single hop broadcast channel overcoming the hidden terminal problem, and an effective multi hop broadcast service by exploiting the connectivity information provided by the protocol. The simulation results presented in the paper prove the effectiveness of ADHOC MAC in terms of access delay to the shared resource and resource reuse when considering a single hop broadcast service. The efficiency of the multi-hop broadcast service is compared through simulation with flooding and with a centralized greedy heuristics that gives an upper bound to the performance. Results show that the distributed ADHOC-MAC multi-hop broadcast mechanism performs closely to the centralized greedy heuristics