Trends of optical networking technologies

Optical layer networking, such as wavelength routing, switching and restoration/protection in an optical layer is a major trend of future optical networks to achieve highly scaleable and survivable optical backbone networks. In this paper, optical layer networking using MEMS-based optical switches both for ring and mesh networks is discussed. Fast protection time of about 20 ms for IP layer has been achieved by the optical layer protection with the optical network protection equipment using a 2D-MEMS in a 500 km bidirectional wavelength path switching ring network. The obtained switching time was comparable to that of optical cross connect using electrical switching fabrics. Regarding the intelligent optical network using the generalized multi-protocol label switching (GMPLS) protocols, interworking between a photonic cross connect based on a 3D-MEMS and an IP/MPLS router has been confirmed. Fast wavelength path provisioning as well as proper path restoration has been also achieved with the GMPLS testbed including three photonic cross connect nodes and 1000 km bidirectional transmission line. Finally, the feasibility of the transparent all-optical network has been demonstrated with the GMPLS testbed.