What is a virtual machine, and why are they so useful?

What are some other forms of virtualization?

The success of VMs in server virtualization led to applying virtualization to other areas including storage, networking, and desktops. Chances are if there’s a type of hardware that’s being used in the data center, the concept of virtualizing it is being explored (for example, application delivery controllers).

In network virtualization, companies have explored network-as-a-service options and network functions virtualization (NFV), which uses commodity servers to replace specialized network appliances to enable more flexible and scalable services. This differs a bit from software-defined networking, which separates the network control plane from the forwarding plane to enable more automated provisioning and policy-based management of network resources. A third technology, virtual network functions, are software-based services that can run in an NFV environment, including processes such as routing, firewalling, load balancing, WAN acceleration, and encryption.

Verizon, for example, uses NFV to power its Virtual Network Services that enables customers to spin up new services and capabilities on demand. Services include virtual applications, routing, software-defined WANs, WAN optimization and even Session Border Controller as a Service (SBCaaS) to centrally manage and securely deploy IP-based real-time services, such as VoIP and unified communications.