Economics of Optical Network Design

The bandwidth efficiency and relative costs for 100 Gb/s WDM transport and switching architectures are compared in North American and pan-European long-haul networks. The first architecture uses muxponders and ROADMs for end-to-end wavelength transport with no digital sub-wavelength grooming. The other two utilize digital OTN switching, as either a standalone OTN switch or a converged integrated WDM/switch system, to efficiently groom services onto WDM wavelengths. Results show the integrated WDM/switch architecture utilizes the fewest WDM wavelengths and client service interfaces, and an integrated WDM/switch architecture using photonic integrated circuit technology provides the lowest operational costs.