Restoration in optical cloud networks with relocation and services differentiation

• Published in: Journal of optical communications and networking Vol. 8; no. 2; pp. 100 - 111
• Main Authors: da Silva, Carlos Natalino, Wosinska, Lena, Spadaro, Salvatore, Costa, Joao C. W. A., Frances, Carlos R. L., Monti, Paolo
• Format: Journal Article Publication
• Language: English
• Published: Piscataway Optica Publishing Group 01.02.2016; The Institute of Electrical and Electronics Engineers, Inc. (IEEE); Institute of Electrical and Electronics Engineers (IEEE)
• Subjects: Availability; Backups; Cloud computing; Computació en núvol; Differentiation; Enginyeria de la telecomunicació; Failure recovery; High-speed optical techniques; Linear programming; Multiplexatge per divisió de freqüència; Network survivability; Optical cloud; Optical communication; Optical fiber networks; Optical fibers; Optical restoration; Restoration; SDN; Service availability; Service differentiation; Service relocation; Strategy; Survivability; Telecomunicació òptica; Wavelength division multiplexing; Wavelength division multiplexing (WDM); Àrees temàtiques de la UPC
• ISSN: 1943-0620; 1943-0639; 1943-0639
• DOI: 10.1364/JOCN.8.000100

Optical cloud networks allow for the integrated management of both optical and IT resources. In this paradigm, cloud services can be provisioned in an anycast fashion; i.e., only the source node asking for a service is specified, while it is up to the cloud control/management system to select the most suitable destination data center (DC) node. During the cloud service provisioning process, resiliency is crucial in order to guarantee continuous network operations also in the presence of failures. On the one hand, a survivability strategy needs to be able to meet the availability requirements of each specific cloud service, while on the other hand it must be efficient in using backup resources. This paper proposes a restoration-based survivability strategy, which combines the benefits of both cloud service relocation and service differentiation concepts. The former is used to enhance the restorability performance (i.e., the percentage of successfully restored cloud services) offered by restoration, while the latter ensures that critical services are given the proper consideration while backup resources are assigned. The paper proposes both an integer linear programming (ILP) formulation, which guarantees optimal results, and a heuristic, which trades the optimality of the solution achieved by the ILP for faster processing times. Simulation results show that the average service availability and restorability performance obtained by both the ILP and the heuristic are very close to that achievable using a protection-based strategy, but with the inherent benefit, in terms of efficient use of resources, offered by a restoration-based approach.