Abstract

WDM optical ring networks are attracting interest thanks to their restoration capability.^1-6 Such networks are also well suited for minimizing the fiber length needed to interconnect system nodes. A ring network needs at least two parallel fibers for restoring traffic in case of a fiber break. Based on this requirement, we propose a new optically restorable WDM ring architecture using simple add/drop circuitry. The result is achieved by using the two fibers as a bus carrying downstream and upstream traffic, respectively, between local stations and a central office or switching hub. Connectivity between local stations is provided through the central office. In case of a fiber break, traffic is restored along two such buses, both connected to the central office. This hub architecture is ideally suited to multimedia services provided by a server. Multisession video ATM traffic was demonstrated with the system. No visible degradation was observed during the 50 msec restoration time. A more detailed description of the system is given in the next section.

© 1996 Optical Society of America