A hybrid metropolitan and long-haul WDM network with end-to-end optical channel layer protection performed by metropolitan WDM equipment

We demonstrate a hybrid metropolitan and long-haul wavelength-division mult iplexed (WDM) network. In this application, two metropolitan WDM rings are connected to each other by two optically amplified point-to-point WDM trans mission systems. The metropolitan WDM equipment performs optical channel la yer protection switching when a failure occurs in the metropolitan rings or in the long-haul WDM transport system. This scheme provides an end-to-end protected network for the transport of high-speed data traffic without requ iring costly SONET terminals. The protection switching time with this schem e is shown to be much faster than traditional SONET protection times. (C) 2 000 John Wiley & Sons, Inc.