Simulation and comparison of path restoration techniques in SDH mesh networks

Abstract

This paper investigates by simulation whether path restoration in a SDH mesh network is more resource effi'cient than traditional protection for a single link failure. The two examined restoration methods are based on the algorithm by Ford and Fulkerson for finding flow augmenting paths, and on the Dijkstra algorithm for finding the shortest path. The methods are studied for two different link upgrading strategies, and for a restoration strategy that adds links to the network. The different methods are compared by simulation with respect to capacity usage, restoration path length (hop count) and number of necessary link upgrades. Our study shows that network restoration can be more resource efficient and requires fewer link upgrades than traditional protection, particularly when applying the Dijkstra method. However, a longer restoration path is required compared to traditional protection. Index Terms path restoration, restoration simulation