Cloud computing represents the next generation of sharing computing and storage resources over a network in a self-service manner without direct involvement in how that computing and storage is resourced. Utilization of the cloud via third-party, web-based providers, such as Amazon EC2, Amazon S3 and Google App Engine, is becoming increasingly common. However, cloud computing is also available to enterprises as private clouds, meant to leverage existing investments in data centers and help overcome some of the physical and political barriers to cloud computing adoption. In general, a private cloud is a centralized shared infrastructure with automated capacity adjustment that internal business units utilize in a self-service manner.