Research On VANET Routing Protocol Based On Named Data Networking

Named Data Networking is a new content-centric networking architecture. In recent years, research shows that NDN has more advantage than traditional IP based architecture in VANET. In this thesis, we propose a VANET routing protocol based on Named Data Networking. The protocol attaches the geographical location information in GeoHash code to the NDN Interest packet(represents request). Using this information, our forwarding strategy make Interest choose the best route to the destination area represented by GeoHash code.In this thesis, we abstract the best routing selection to the shortest path problem of a directed graph. Regarding the road network as a weighted undirected graph, this thesis considers both vehicle density and length of road to design the weight calculation formular, designing a best routing algorithm based on Dijkstra algorithm. We also proposes a delayed forward mechanism using a timer. Before forwarding packet, each node set the timer propotional to the distance with last hop node, thus the packet can be forwarded as far as possible. The delayed forward mechanism can also help to reduce the unecessary wireless signal conflict.Always forwarding the Interest packets along the best route may lead to network overload. In order to solve this problem, we design a load balance mechanism. We use a "Penalty Time" strategy, a communication node can add an additional delay before forwarding a packet when it detected the wireless signal conllision rate is high. Eventually Interest packet can be forwarded along the suboptimal routing path with a given ratio.This thesis also propose a mitigating mechanism against Interest Flooding Attack. Each node can detect potential flooding attack by statistic the interest satisfaction status, and then restrict the node with low interest satisfaction to forward more insterest.Finally, this thesis runs simulation under several scenarios using SUMO and NS3. Compared to the typical geographic routing protocol GPSR, we prove that our protocol has higher Interest satisfaction ratio and higher throughput. In overload scenario, our protocol can effectively balance the load. And the Interest Flooding simulation proves that the mechanism can mitigate attack effect for valid Interest satisfaction ratio.