A Gateway Discovery Approach Using Link Persistence Based Connected Dominating Sets for Vehicular Ad Hoc Networks

In roadside gateway (RG) based vehicle ad hoc networks, the vehicles have difficulty in maintaining a stable route to the RG due to their high mobility. In addition, the redundant transmissions of an RG advertisement message transmitted to inform vehicles of the presence of RG can cause high control overhead. A new gateway discovery approach using tree topology is proposed to reduce control overhead as well as to cope with the high mobility of vehicles. The proposed approach employs the notion of connected dominating set (CDS) such that all nodes can receive the advertisement message if every vehicle in the CDS retransmits the message once. A prediction function of link persistence time is used in building the CDS, which replaces the node Id as primary key, to increase the stability of the route from each vehicle to an RG. The proposed protocol was evaluated comparatively with the traditional approaches, by resorting to simulation with various mobility scenarios generated by the VanetMobisim tool.