A Cooperative Road Topology-Based Handoff Management Scheme

Selecting the most stable partner on a vehicular ad hoc network (VANET) is a challenging task due to its unique mobility, driver behavior, and networking requirements. Although new partner selection protocols are introduced for mobile ad hoc networks and general mobility, there is a lack of a partner selection protocol that is suitable for VANET. This paper discusses the requirements of such a protocol and presents a handoff protocol that is tailored to VANET requirements. We leverage the use of partner-assisted handoff by introducing a vehicle link expiration time (VLET) metric that is designed to maximize intervehicular connections. The suitability of the proposed protocol is carefully studied and then compared to state-of-the-art protocols. A performance analysis comparing average connection time, connection stability, handoff delay, and success rate is carried out. The simulation results show that the proposed protocol enhances the handoff on VANET and can increase the average connection time among vehicles by 175%. This research advocates the importance of using road topology and traffic information for any future VANET handoff protocols and paves the way for future research on using the introduced VLET in other VANET applications.