Quadtree-based optimal path routing with the smallest routing table size

Routing schemes play an important role in the network. In terms of the information utilized by routing, the existing schemes can be classified into two main groups: topology-based routing and geographical routing. The former can always guarantee the optimal path, but its routing tables often contain massive entries which seriously impact the algorithm's efficiency. The latter can not guarantee the optimal path, but its routing table size is fairly small. Based on the characteristics of above routing mechanisms, we present a novel geographical routing mechanism which can guarantee the optimal path with the minimum overhead. By utilizing the geographical location information and the quadtree data structure, the routing table size can be reduced to its information-theoretic lower bound. Our theoretical analysis suggests that the performance of the routing table size of our proposed scheme is better than the best IP-based routing table compression result in the literature.