LOCNET-an experimental communications system using optical routing

Experiences gained with the installation and operation of an experimental communication system are reported. The system uses distributed switching in its narrow-band part, integrating ISDN services and high-speed data communication, and a star coupler as a central device. LiNbO3 optical switches behind the star coupler prevent line tapping. In the wideband subsystem, optical routing is used for videophone. The central device is a space-division-switching unit consisting of cascaded 4*4 LiNbO3 switching matrices. Both the narrowband and wideband parts of the system have been operated with bit error rates less than 10-9.