Criteria for Selecting Subsystem Configuration in Creating Large-Scale OXCs

We investigate in detail the performances of different subsystem-based modular optical cross-connect (OXC) architectures that can be expanded to cover large port counts. They include ring, linear, and main/junction types, all of which are proved to substantially reduce total hardware scale compared to the conventional architecture. The reduction in necessary number of wavelength selective switches (WSSs) can be more than 70% for OXCs with about 50 x 50 ports, where the accepted traffic offset is about 2%. The maximum number of WSSs traversed by optical paths is also reduced by more than 50% for Pan-European (26 nodes) and 5 x 5 regular mesh networks.