Automatic routing using multiple prefix labels

We present Multi-label Automatic Routing (MAR), the first compact routing protocol that attains a low path stretch (ratio of selected path length to the optimal path length) while maintaining a low routing state for mobile networks. MAR is resilient to node movements in the network. In MAR, nodes assign themselves labels based on their location in the network through a distributed algorithm. Distributed Hash Tables (DHTs) for the node to label mappings are established in some anchor nodes. Once the labels are established, the routing is automatic based on the positional labels of the nodes and DHT lookups. This eliminates flooding completely. Unlike traditional routing protocols MAR does not need destinations-based routing tables. Hence, MAR has a small routing state. With the use of multiple labels per node, the average path length is close to the shortest path and there are multiple paths between source and destination nodes. In Qualnet simulations MAR shows a path stretch close to or better than traditional table-driven and on-demand protocols like OLSR and AODV. Simulation results also show shorter end-to-end delays due to the automatic routing. The delivery ratio of MAR is comparable to these traditional protocols but with a significantly lower network overhead.