Optical restoration at the wavelength-multiplex-section level in WDM mesh networks

Summary form only given. Amid mounting evidence of explosive growth in demand for long-haul, high-bit-rate services, it is becoming increasingly important to devise economical ways to restore wavelength-division multiplexing (WDM) networks that transport large aggregate traffic volumes. There are two broad means of addressing this challenge. One approach restores traffic at the wavelength-path level-i.e., by independently routing individual restored wavelengths. The second restores traffic aggregated at the wavelength-multiplex-section (WMS) level using, for example, the optical-switch-based approach. We evaluate the prospects for such WMS-level restoration in national-scale long-haul WDM mesh networks.