ROADMs: Reconfigurable Optics for Agile Networks

The growth of innovative, transformative Internet-based services has been fueled by an explosion of optical network capacity—an expansion that has hinged on a concomitant drop in the cost per bit of data transmission. Much of that cost reduction has come from advances in optical transceiver and amplifier technologies: increased bit rate per wavelength; an increased number of wavelengths carried in a single fiber; increased optical reach. Less widely recognized, however, has been the role of a fourth critical enabler: increasingly flexible optical wavelength routing.