Optically restorable WDM ring network using simple add/drop circuitry

An optically restorable wavelength division multiplexing (WDM) ring network carrying ATM traffic is presented. It uses a new architecture with simple add/drop circuitry allowing traffic restoration in case of a ring breakage by independent local actions at the affected nodes. Multisession video traffic at 155 Mb/s was demonstrated between stations distributed along the ring. No visible video degradation was observed during the 50 ms restoration time caused by a ring breakage.