An approach for enhancing fixed alternate routing in dynamic wavelength-routed WDM networks

A novel planning algorithm, namely capacity-balanced alternate routing (C-BAR), is proposed for enhancing fixed alternate routing in dynamic wavelength-routed WDM networks. With C-BAR, alternate paths between each source-destination (S-D) pair are defined at the network planning stage according to the load distribution and the location of each S-D pair, so that the routing of lightpaths can take the most advantages of the load-balancing characteristic of the alternate paths. A methodology for designing the number of alternate paths between an S-D pair for achieving a specific performance requirement is demonstrated. Simulation is conducted to examine the proposed approaches, and show that the C-BAR algorithm can significantly improve the performance in blocking probability compared with the other reported RWA schemes.