The essential value of the cloud is derived from an agile storage and server resource pool, and cloud networks are key to this model. Without the right network connectivity, servers and storage form no pool at all and users can't link to their applications. Organizations transitioning to the cloud must consider new kinds of network design and connectivity, as well as Quality of Service (QoS) management that will enable them to integrate private and public cloud resources and ensure optimized application performance.

Providing users application access: VPN vs. the virtual data center

Cloud computing must link workers' fixed view of their applications with a flexible vision of where and how those applications are run, and the network's job is to support that. There are two primary options for integrating cloud resource pools. One is to build a "virtual data center" by linking company data centers and public cloud resources behind a controller, which can be a software element or a load-balancing switch. That component provides user application access. The other option is to create a VPN that connects applications and users no matter where they're hosted. Both options have benefits and limitations.