Network virtualization (NV) is using network resources through a logical segmentation of a single physical network, or making multiple networks appear as one in a virtual data center. Network virtualization is achieved by installing software and services to manage the sharing of network resources among storage, computing cycles and applications. Network virtualization treats all servers and services in the network as a single pool of resources that can be accessed without regard for its physical components. Software-defined networking (SDN) is one type of network virtualization. The term network virtualization has been used to describe many things, including network management, storage virtualization, and even grid computing.