Abstract
Recently, vehicular networks and inter-vehicle communication have received attention from the research community and the automotive industry. In this context, many services are deployed in vehicular networks that are beneficial to drivers and passengers. Service discovery in vehicular networks is vital to make such services useful. However, due to the lack of communication reliability in vehicular ad hoc networks, it is necessary to implement fault-tolerant techniques during the discovery of service providers in vehicular networks. Very few service discovery protocols for vehicular networks have considered fault tolerant techniques, which are very important for the efficiency of service discovery. Fault tolerant techniques improve service request satisfaction and reduce dropped connections due to faulty components between the service provider and the service requester. In this paper, we propose a fault tolerant location based service discovery protocol for vehicular networks which can work well under service provider failures, communication link failures and roadside router failures. Our protocol permits the discovery of location based services where the requester specifies the region of interest within the request. Our protocol uses an infrastructure support consisting of clusters of roadside routers formed in specific regions in the vehicular network. In addition, service discovery messages are integrated into the network layer and use channel diversity in order to improve service discovery efficiency. We describe our fault tolerant location based vehicular service discovery protocol (FTLocVSDP) and discuss its proof of correctness and performance evaluation. We prove that the success rate is improved in the roadside router failure and in the communication link failure scenarios by 50% and 30%, respectively, compared to the location based service discovery protocol for vehicular networks (LocVSDP) which does not consider fault tolerant techniques.