Signaling protocols for survivable all-optical networks

Abstract

Survivable mechanisms, including fault localization and connection restoration, are achieved by means of electronically analyzing overhead bits in opaque optical networks. However, unlike opaque networks, transparent all-optical networks are unable to examine signal quality at transponders. Consequently, locating and isolating failures and attacks (intentional failures) in transparent optical networks are much harder than in opaque networks. Likewise, connection restoration and path rectification are more complex. Therefore, previously defined survivable terminologies, models, and techniques should be evolved and re-designed with respect to the dissimilarities to be applicable to all-optical networks. Accordingly, this thesis proposes several fault detection protocols, including Fault Localization Signaling Protocol, Rolling-back Signaling Protocol, and Limited-perimeter Vector Matching Protocol, and a number of connection restoration and re-routing techniques, such as Open Link Restoration Protocol, Minimum Weighted-path Restoration Protocol, and Signaling Nested Reservation Protocol, which are feasible in all-optical communication networks. The proposed protocols are all implemented by signaling in the supervisory channels of the overlay model. Since these protocols use controlling signals only as triggering signs, they are not involved in substantial processes and delays. As a result, they are compatible to high-speed all-optical networks. However, the signaling mechanisms embedded in these protocols utilize additional bandwidth from the control network.