Provisioning Policies for Elastic Computing Environments
Resources experience dynamic load as demand fluctuates. Therefore, resource providers must estimate the appropriate amount of resources to purchase in order to meet variable user demand. With the relatively recent introduction of Infrastructure-as-a-Service (IaaS) clouds (e.g. Amazon EC2) resource providers may choose to outsource demand as needed. As a result, a resource provider may decide to decrease his initial capital outlay and purchase a smaller resource that meets the needs of his users the majority of the time while budgeting for future outsourcing costs. When bursts in demand exceed the capacity of the resource, a resource provider can use elastic computing to outsource excess demand to IaaS clouds based on a defined budget.