Cloud computing represents a fundamental shift in the delivery of information technology services that has been changing the computing landscape. Indeed, over the past several years, cloud computing has rapidly emerged as a widely accepted computing paradigm. The research and development community has quickly reached consensus on the core concepts such as on-demand computing resources, elastic scaling, elimination of up-front capital and operational expenses, as well as the new pay-per-use business model for computing and other information technology services provided by the cloud. With the adoption of virtualization, service-oriented architectures, and utility computing, there is also consensus on the enabling technologies necessary to support this new consumption and delivery services model. Additionally, the customers' demand to meet quality-of-service requirements and service-level agreements, including security, is well understood.