This work proposes an enhancement of the GPSR routing protocol to improve the performance of point-to-point IP-based voice communications in a vehicular ad-hoc network. Our enhancement reduces significantly the end-to-end delay in ad-hoc networks using a TDMA-based medium access control protocol. The proposed enhancement of GPSR routing basically consists in an optimized choice of the next hop node based on the time slot used by the node to transmit outgoing packets. We evaluate the performance improvements in terms of end-to-end packet delay, packet loss ratio and synthetic mean opinion score that users would assign to the voice communications. We show that, with our procedure, it is possible to obtain a significant performance improvement in terms of network scalability and quality of IP telephone calls
['Giuseppe Caizzone', 'Walter Erangoli', 'Paolo Giacomazzi', 'Giacomo Verticale']
An enhanced GPSR routing algorithm for TDMA-based ad-hoc networks