We present a technique for compression of shortest paths routing tables for wireless ad hoc networks. The main characteristic of such networks is that geographic location of nodes determines network topology. As opposed to encoding individual node locations, at each node our approach groups the remaining nodes in the network into regions. All shortest paths to nodes in a specific region are routed via the same neighboring node. In this paper, we propose an algorithm for dividing a network field into distinct regions to minimize routing table size while guaranteeing shortest path routes. We show that this problem is NP-hard, propose a heuristic to find efficient solutions, and empirically demonstrate the resulting system performance from the perspective of compression ratio and scalability. In our experiments, routing tables compressed using this technique, require 88.9% to 97.9% less storage than uncompressed tables. In order to achieve energy efficient routing, we propose an augme...