Performance Analysis and Improvement Content Discovery Protocols Over Vehicular Networks

Recently P2P networks and theirs applications have become increasingly popular. On the other hand, considering ever increasing industrial and scholarly popularity of Vehicular Ad-hoc Networks (VANETs), implementation P2P network over VANET has attracted attentions recently. One of the most important applications in P2P networks is content discovery. This paper presents an evaluation framework which evaluates challenges in VANET and their impact on performance of content discovery protocols including structured or unstructured ones. This evaluation is based on simulation and mathematical modeling. For mathematical modeling, Generalized Random Graph has been used. Results of evaluation clarified a higher performance on unstructured protocol and also impact of movement pattern and environmental characteristic of VANET on performance on content discovery protocols. Furthermore, based on evaluation results, some modifications in the manner of comprising overlay network were presented. This modification emphasizes matching of overlay networks and underlay networks and also using traffic flow of vehicles in comprising overlay links. Positive impact of this modification has been shown by simulation and mathematical modeling.