Routing algorithms for anycast messages

We propose and analyze three routing algorithms for anycast packets: source-destination based routing with weighted random selection (SD/WRS); destination based routing with weighted random selection (D/WRS); and the shortest shortest path first (SSPF) algorithms. The SSPF algorithm is a simple extension to the traditional SPF algorithm for routing unicast packets. The SD/WRS and D/WRS algorithms explicitly take into account characteristics of anycast message traffic and its recipient group. As a result, our simulation study shows that both the SD/WRS and D/WRS algorithms perform much better than SSPF in terms of average end-to-end packet delay. In particular, SD/WRS performs very close to a dynamic optimal algorithm in most cases. Our algorithms are simple, efficient and compatible with the most of existing routing technologies. We also formally prove the loop free and correctness properties for our algorithms.