This application is a continuation of US patent applica tion Ser. No. 1 1/612,040, filed Dec.
18, 2006, now US Pat. No. 7.324, 752, which is a divisional of US patent applica tion Ser …

Part of an inputted optical add signal 118 is reflected by a mirror 117, and is thereby inputted
into an optical wavelength multiplexer 105 in the reverse direction so that the optical add …

An optical system with a first and second network tiers. The first network tier includes a
plurality of major nodes optically interconnected by at least one transmission path. The …

Kelly et al.,“80Gbit/s all-optical regenerative wavelength conversion using semiconductor
optical amplifier based interferometer.” Elec tronics Letters, vol. 35. No. 17. Aug. 1999, pp …

A method and an apparatus to provide optical equipment protection have been disclosed. In
one embodiment, the method includes splitting an incoming optical signal into a first and a …