Dimensioning Resilient Optical Grid/Cloud Networks
Optical networks play a crucial role in the provisioning of grid and cloud computing services. Their high bandwidth and low latency characteristics effectively enable universal users access to computational and storage resources that thus can be fully exploited without limiting performance penalties. Given the rising importance of such cloud/grid services hosted in (remote) data centers, the various users (ranging from academics, over enterprises, to non-professional consumers) are increasingly dependent on the network connecting these data centers that must be designed to ensure maximal service availability, i.e., minimizing interruptions. In this chapter, the authors outline the challenges encompassing the design, i.e., dimensioning of large-scale backbone (optical) networks interconnecting data centers. This amounts to extensions of the classical Routing and Wavelength Assignment (RWA) algorithms to so-called anycast RWA but also pertains to jointly dimensioning not just the network but also the data center resources (i.e., servers). The authors specifically focus on resiliency, given the criticality of the grid/cloud infrastructure in today’s businesses, and, for highly critical services, they also include specific design approaches to achieve disaster resiliency.