A Research Of Geographic Routing In Ad-hoc Networks

The research of Ad Hoc network has become a hot, this paper focuses on geographic routing algorithm in Ad Hoc network.all the nodes in Ad Hoc network are also with double function. Because of the mobility, self-organization of nodes in ad hoc network, the routing algorithm is different from other network routing algorithms. Routing based on geographic position is one of the widely used routing.It assumes that all notes in ad hoc network know their own positions, their 1-hop neighbors' positions as well as the destination's. DSR is consist of searching and maintaining of routing. GR is a simple greedy geographic forwarding algorithm, for a forwarding node, the locally optimal choice of next hop is the neighbor geographically closest to the packet's destination. GPSR is Upgraded version of Greedy Routing, can solve the void of GR. The packet is forwarded greedily, and forwarded along the perimeter when there is a problem, return to greedy mode if it is possible.This work simulated GR, GPSR and DSR with ns-2 in several different scenes, and summarized their own superiority on packet delivery success rate, routing protocol overhead and path length, and analysis of these simulation data.GPSR can guarantee the discovery of route, avoid unreachable of existing path. The right rule of GPSR can solve the void of GR, it is a circuitous routing method, average routing path length can not reach to optimal.This paper makes some work on GPSR, Add a packet storaged the hops of transmission in packet header, the nodes in Perimeter mode Storage last route information, Comparative routing hops, and get the best route. The simulation data analysis show that the GPSR-PRO algorithm can achieve the desired effect on shorter average route.