Migrating to a Next Gen WDM Network

A collection of slides from the authors\´ conference presentation is given. The convergence toward all over IP and the fast growth of the traffic make clearly the WDM layer as the core transport federating layer. This case study, performed on the France Telecom WDM network shows that: semi-transparent network architectures allows for significant CAPEX saving; WB and WS introduction dramatically simplifies network architectures and planning activity; they also bring additional CAPEX savings; migrating to a fully agile "Next Gen" WDM network might be challenging with currently proposed architectures.