Analysis of wavelength conversion in all-optical express backbone networks

Sparse wavelength conversion is essentially achieved for free in all-optical express networks by taking advantage of wavelength conversion at regeneration sites. As has been shown in numerous studies, sparse wavelength conversion is sufficient for achieving utilization levels close to those of networks with full wavelength conversion. We discussed qualitatively why this should be expected for all-optical express networks, and further demonstrated this using four carrier networks. Thus, the significant savings in capital and operating expenses and the fast-provisioning benefits of all-optical networks can be attained with very little loss of network efficiency.