Adaptive routing and wavelength assignment algorithms for hierarchical architecture in ASON

The hierarchical routing and wavelength assignment problem in Automatic Switched Optical Network (ASON) is researched. Based on our analysis, three adaptive algorithms called MLLR (Multi-Layer Least Loaded Routing Algorithm), WMLCR (Wavelength-graph-based Multi-Layer Least Congestion Routing Algorithm) and BMR (Backtracking-based Multi-Layer Routing Algorithm) are proposed. A platform named AHORSP (ASON based hierarchical optimal routing & signaling platform) supporting our routing scheme is proposed and demonstrated. The simulation shows that the proposed algorithms can have comprehensive application on the basis of their convenience to be realized, low BP performance and acceptable operation time.