No precise crossover to new and improved optical networks. Wavelength division multiplexing vendors are boosting the number of wavelengths that can be transmitted per fiber, boosting the distance optical signals can travel without being regenerated electrically. The industry is also developing optical cross-connects that eliminate the need to convert waves into electronic signals.
Optical networks have a major management issue, as well.
Sonet is the manager of choice today, but vendors are focusing on optical management systems that can more readily handle high-speed IP and ATM traffic. In its labs, Lucent Technologies Inc. has run transmission rates of 1 terabit per second of data using 100 wavelengths at 10 Gbps each over distances of about 250 miles. Vendors are also working on increasing the capacity per wavelength-with potential rates as high as 40 Gbps compared to the 2.5 Gbps or 10 Gbps per wavelength used today. The next generation of optical amplifiers will effectively double the potential number of wavelengths that can be transmitted on one fiber by operating at a slightly higher frequency, says Jack Wimmer, MCI's executive director of network technology and planning. Sonet Add-Drop Multiplexers convert optical signals to electrical so traffic can be added or dropped as needed.