OADMs in Optical Networks: Architecture and Algorithms

Ultra-long haul transmission systems, with ability to go thousands of km without electrical regeneration, together with Optical Add-Drop Multiplexers (OADMs) and optically transparent photonic cross-connects enable cost-effective optical transparency. In this paper, we discuss OADM architectures, appropriate network architectures in which they can be prominently used, and network design challenges to be addressed. We also present economic results testifying to the ability of our innovative OADM techniques. In particular, we discuss asymmetric structures in OADMs used in multi-connected nodes, the architectural flexibility (network topology, OADM orientation, end terminals and regeneration placement, and demand routing) allowed by such asymmetry, and the algorithmic problems that we have solved.