A new approach to on-demand loop-free routing in networks using sequence numbers

A new protocol is presented for on-demand, loop-free routing in ad hoc networks. The new protocol, called the labeled distance routing (LDR) protocol, uses a distance invariant to establish an ordering criterion and per-destination sequence numbers to reset the invariant resulting in loop-freedom at every instant. The distance invariant allows nodes to change their next hops or distances to destinations without creating routing-table loops. The destination sequence number, which only the destination may increment, permits nodes to reset the values of their distance invariants. The performance of LDR is compared against the performance of three other protocols that are representative of the state-of-the-art, namely AODV. DSR and OLSR; LDR's performance is shown to be far better than the other three protocols. (c) 2005 Elsevier B.V. All rights reserved.