Improving bandwidth efficiency in fault‐tolerant opaque IP over optical mesh networks

Adequately providing fault tolerance while using network capacity efficiently is a major topic of research in optical networks. In order to improve the network utilization, grooming of low-rate connections in optical networks has been usually performed at the edge of the network. However, in all-optical networks once a channel is assigned, its entire capacity is dedicated to the users independently of its grooming capabilities. As current users don't usually require such big capacities, bandwidth inefficiencies still occur. In this paper we address this issue introducing unlimited grooming per link (UGPL), a new restoration mechanism for opaque mesh optical networks that grooms connections on a per-link basis. Simulation results show that UGPL provides the best bandwidth efficiency and the best blocking probability compared to traditional 1 + 1 protection and 1 : N end-to-end sharing schemes. Furthermore, we show that the 1 : N end-to-end restoration scheme provides no benefits over the simpler and faster 1 + 1 protection scheme.