A next-generation optical regional access network

We describe an optical regional access network which combines electronic IP routing with intelligent networking functionality of the optical WDM layer . The optical WDM layer provides such networking functions as network logic al topology reconfiguration, optical flow switching to offload traffic and bypass IP routers, wavelength routing of signals, protection switching and restoration in the optical domain, and flexible network service provisionin g by reconfigurable wavelength connectivity. We discuss key enabling techno logies for the WDM layer and describe their limitations. The symbiosis of e lectronic and optical WDM networking functions also allows support for hete rogeneous format traffic and will enable efficient gigabit-per-second user access in nest-generation Internet networks.