Arrival Time Dependent Shortest Path by On-Road Routing in Mobile Ad-Hoc Network

Arrival time dependent shortest path finding is an important function in the field of traffic information systems or telematics. However large number of mobile objects on the road network results in a scalability problem for frequently updating and handling their real-time location. In this paper, we propose a query processing method in MANET(Mobile Ad-hoc Network) environment to find an arrival time dependent shortest path with a consideration of both traffic and location in real time. Since our method does not need a centralized server, time dependent shortest path query is processed by in-network way. In order to reduce the number of messages to forward and nodes to relay, we introduce an on-road routing, where messages are forwarded to neighboring nodes on the same or adjacent road segments. This routing method allows to collect traffic information in real time and to reduce the number of routing messages. Experiments show that the number of forwarded messages is reduced in an order of magnitude with our on-road routing method compared to LAR-like method. At best, our method reduces about 57 times less messages.