Linear lightwave networks: how far can they go?

A novel type of lightwave network architecture that is based on establishing controllable, optically transparent paths among network users is described. The objective is to provide optical connections on demand. These connections would support a high degree of flexibility, including user-chosen modulation formats and bit rates, for large numbers of user stations (e.g., 100000) using mesh-type topologies that are spread over geographical areas that may extend to diameters of several thousand kilometers. The networks in question perform only linear operations on optical signals, essentially operating as a dynamically controlled `ether´ within which light beams are selectively directed between prescribed source-destination pairs. Because these linear lightwave networks are controllable, they are capable of being reconfigured in response to changing load conditions or component failures