Data-center operators, telecom carriers, and cloud service providers are striving to optimize their strategies for decoupling network functions from the underlying hardware, which is critical to increasing agility and lowering costs. That abstraction is central to SDN usages, where virtualized network resources are programmatically provisioned, coordinated, and controlled by management software, dynamically as changing requirements warrant. Accordingly, physical assets can be utilized more efficiently, and novel services and usage models can be supported rapidly.
Similarly, NFV capabilities replace fixed-function hardware with implementations fully in software that run more cost-effectively on general-purpose, standards-based servers. Virtualized software functions are assembled on demand to create an open-ended variety of communications capabilities, including those needed to support novel service offerings, without requiring the addition of specialized hardware. SDN and NFV reduce costs and increase business agility, fostering competitive advantages, but those goals are more widely agreed upon than the means to achieve them are.