On the Scalability Problem of Highway Ad Hoc Network

Vehicular ad hoc network in a highway is composed of high speed vehicles or nodes which induce fast topology changes in their configuration. In order to solve the connectivity and scalability problems of VANETs, we introduce the architecture of a vehicular hybrid ad hoc network (VHANET). Using some routing protocol extensions, the VHANET allows ad hoc islands to be interconnected among each other using a infrastructure network. Our simulation results show that the performances, compared to a flat network, are greatly enhanced. In addition, we study a nearly optimal AP density for the use of our architecture.