http://www.itbusinessedge.com/whitepapers/35724910/96000/3891210/111111
First, it is usually fully virtualized and accessed via the internet (or cloud). The technical concept actually isn’t new. Companies have been implementing their own virtual private data centers for years. However, companies are now looking to adopt cloud computing as a managed service to reduce costs as well as time to implement new infrastructure, platforms or software applications. One of the fastest growing areas of cloud services is utilizing it for data storage and managed services to improve application and data accessibility. There are two types of cloud data centers – virtual private or virtual public networks. Larger companies have typically created their own virtual private cloud data center. However, that isn’t an option for many small to mid-sized businesses. The initial capital required to build a virtual private cloud is cost prohibitive for many their only option is to turn to remote or branch offices to access applications and or services via a secure internet connection.