Destination Discovery Oriented Position Based Routing in VANET

Routing in vehicular network is a major challenge and research area. The major threat is the node density and high dynamics of the network topology. Existing position based routing protocols try to solve this by forwarding data in greedy forwarding way. However, they solely depend upon Location services. Location service makes a lot of transactions in the network traffic. Proactive routing protocols find the destination information by flooding RREQ messages. But flooding also increases routing overhead. Again they maintain a route from source to destination. The lifetime of route is same as the life time of the edge with smallest life time. This makes it vulnerable to path break up, which leads to frequent RREQ flooding. We have tried to solve the above stated problems in three manners: (1) Location service overhead problem: We have not used any location server; rather a destination discovery message is sent from source to destination which finds the destination direction relative to source. If the destination direction is known this is not used. (2) Flooding of RREQ problem: We have not used any flooding. We have used only unicast messages. (3) Path break-up problem: We have not used any dedicated path from source to destination for data transmission. Rather we have selected the next hop in the direction of destination to send a packet using an algorithm called smart next hop selection algorithm (SNESA). Also we have tried to reduce the frequency of HELLO messages using neighbor update algorithm which validates the neighborhood of a node.