WDM Networks; A US Perspective

Optical amplifiers and wavelenght-division-multiplexing (WDM) have enabled rapid progress in lightwave communications: large-scale deployment has begun of 20 Gb/s capacity WDM systems in the terrestrial network using 8 wavelenght channels, WDM computer networks are on the market, the WDM Africa I network was proposed, and Tb/s capacities per fiber have been demonstrated in the laboratory using 25 WDM channels. Large coordinated programs are exploring transparent optical networking that can provide flexibility, survivability and reconfigurability via WDM add/drops and VVDM cross-connects. Studies cover the range from WDM technology, WDM rings, and WDM architectures through network management and control.