ZRESTORE: A Link Restoration Scheme with High Aggregation and No Reservation

This paper proposes a new link restoration scheme for optical networks. Our scheme uses dynamic provisioning of bypass routes to effectively utilize bandwidth for restoration. The bypasses are pre-selected but not reserved. Bandwidth is requested in aggregate, resulting in control traffic savings. A unique idea of over-protecting channels on the links for future work savings has been proposed in this paper. Our scheme assumes the knowledge of global topology (but not capacity) information at each node. Using simulation results we show that our scheme is very competitive in terms of restoration times and restorability even in very high load conditions.