devices Virtualization to decrease the number of physical servers required to store files and run applications Private Clouds within Data Centers Enterprise and commercial organizations are cautious about moving their data center functions to the cloud. As detailed in Chapter 1, concerns about security, portabil- ity, and loss of control over data are the primary factors in their caution. However, IT directors are under pressure from CEOs and CFOs to operate their data centers as Data Centers and IP Private Branch Exchanges efficiently and cost-effectively as cloud providers. For example, when IT departments request money for staff, software, or equipment, top management will likely ask how much cheaper it would be to use a cloud provider. In addition, economic downturns have made organizations careful about spending money. All of these factors, together with technological improvements, are leading the drive to improve operational effi- ciencies in onsite data centers. These streamlined data center operations are often termed private clouds. One of the best ways for an organization to realize efficiencies is to consolidate into central data centers functions that were previously located in numerous remote offices and department. Centralization and streamlined data center operations are enabled in large part by storage, server, and switch virtualization. Increased speed in data networks is another key impetus to creating private clouds. Virtualization has made it more cost-effective to centralize applications and storage rather than installing complex applications and their attendant support requirements in individual departments or remote sales and branch offices. High-speed networks utiliz- ing WAN and application acceleration software ensure that people accessing applica- tions remotely from branch offices do not experience delays. Refer to Chapter 1 for an explanation of WAN acceleration and virtualization. Thus, the term "private cloud" refers to efforts by private companies to provide services to end users i