Distributed routing with labeled distances

The author presents, verifies, and analyzes a new routing algorithm called the labeled distance-vector routing algorithm (LDR), that is loop-free at every instant, eliminates the counting-to-infinity problem of the distributed Bellman-Ford (DBF) algorithm, operates with arbitrary link and node delays, and provides shortest paths a finite time after the occurrence of an arbitrary sequence of topological changes. In contrast to previous successful approaches to loop-free routing, LDR maintains DBF´s row-independence property and does not require internodal coordination spanning multiple loops. The new algorithm is shown to be loop-free and to converge in a finite time after an arbitrary sequence of topological changes. Its performance is compared with the performance of other distributed routing algorithms