Restoration Based on Bandwidth Degradation and Service Restoration Delay for Optical Cloud Networks

The use of an optical fiber infrastructure to accommodate cloud services is gaining a lot of momentum. This is mainly driven by the bandwidth and latency performance that optical transmission can guarantee. On the other hand failures in the optical infrastructure may result in the concurrent loss of a possibly high number of cloud services. For this reason, being able to offer cloud service resiliency at a contained cost is of the utmost importance for operators. This paper proposes a heuristic for the restoration of optical cloud services in the presence of a single fiber link failure. The heuristic leverages on two parameters specified in the service class (i.e., restoration delay and bandwidth degradation) in order to make the best use of the available optical resources during the recovery process. The numerical results presented in the paper show that the proposed restoration algorithm is able to improve cloud service restorability without a negative impact on the cloud service blocking probability.