Novel Routing Algorithms for Hierarchical Architecture in ASON

The hierarchical routing infrastructure in automatic switched optical network (ASON) is researched. Three operational algorithms MLLR (multi-layer least loaded routing algorithm), MLCR (multi-layer least congestion routing algorithm) and MROB (multi-layer routing algorithm based on backtracking) are proposed. In these algorithms, the resource coordination and balancing of multi-domain and multilayer are considered based on the fixed alternate hierarchical routing. A platform named AHORSP (ASON based hierarchical optimal routing & signaling platform) supporting our routing optimization scheme is proposed and demonstrated. Based on the platform the average block probability can be reduced effectively with acceptable time performance by these algorithms.