Designing Fast and Bandwidth Efficient Protection Scheme for WDM Optical Networks

In this paper, we introduce the Pre-cross-connected Segment First —PXSFirst protection scheme; a new path-based protection schemes for WDM optical networks. The goal of the PXSFirst scheme is to achieve fast recovery, while maximizing bandwidth sharing to improve bandwidth utilization. Similar to pre-cross-connected trails (PXTs) protection scheme, PXSFirst ensures that all backup paths are pre-crossconnected, and hence eliminates the switching configuration delay along backup paths. However, unlike the PXT scheme, where backup paths can only share trails, PXSFirst breaks backup paths into smaller segments by existing end nodes, and hence, increases the possibility of bandwidth sharing. Extensive simulation results for different network topologies and under different traffic patterns show that the proposed scheme has better blocking performance and less bandwidth utilization (an average of 11.0% reduction) compared to existing PXT protection schemes.