NFV vs. SDN: What’s the Difference?

Telecommunications companies have taken a strong interest in SDN. At the same time, more enterprise use cases for NFV have been emerging. Network functions virtualization (NFV) and software-defined networking (SDN) are related and both use network abstraction. However, SDN separates and abstracts the control plane into software from the data plane, which remains in hardware, and NFV is a combination of separating wholesale network and security functions into specific software, then service chaining them.


When network function virtualization (NFV) first started making headlines about four years ago, the initial use cases for the technology had more to do with the telecommunications industry rather than the average enterprise.

That shouldn’t come as much of a surprise. After all, the white paper that kicked off interest in NFV came out of a group that was part of the European Telecommunications Standards Institute (ETSI). Those involved in writing the paper were almost exclusively made up of representatives from telecommunications providers in Europe and elsewhere around the world.

When NFV comes up as a discussion topic today, though, it’s not just in relation to the telecommunications industry. Over the last couple of years, more of the discussion has centered around how enterprises can make use of the technology.

Historically, NFV has typically been thought of as a telco technology, whereas related software-defined networking (SDN) technologies have been considered something more likely to be adopted by the enterprise. That’s changing.

For enterprises, there are plenty of reasons to at least investigate NFV for use in their own businesses. The technology can help reduce capital expenditures (instead replacing them with more modest operational expenditures). It offers the ability to have more diminutive fault domains. And it makes applications more portable, which is increasingly more of a necessity to enterprises.

NFV has the potential to play a significant role in the rapidly growing market of software-defined WAN (SD-WAN). By combining network and security virtual network functions (VNFs) with an SD-WAN architecture, enterprises can gain a better price/performance ratio for a variety of network services.
NFV technologies aim to replace network appliances with virtualized versions, enabling the creation of on-demand network services and simplifying management by creating a central point for network orchestration. After all, there’s logic in building a software-defined WAN based on true software.

As an SDxCentral article pointed out, there are several enterprise use cases for NFV and SDN. Some of the use cases presented by the all things software-defined news site are more specific to SDN than NFV, but there are a few use cases (virtual core and aggregation, data center optimization, etc.) where NFV plays a more central role in the enterprise.

The future of NFV will be linked to both the enterprise and telecommunications sectors. Use cases are still emerging and will continue to do so. The market for NFV is growing rapidly. A 2016 IHS Infonetics report predicts a five-fold increase in NFV-related revenue between 2015 and 2019, resulting in an expected $11.6 billion market.

Much of the growth will be in the carrier realm, but a recent QuinStreet Enterprise survey found that 16 percent of enterprises have already deployed some form of NFV. Another 44 percent are currently evaluating NFV to see how it can fit into their organizations.

The message seems clear: NFV was born in the telecommunications sector, but it’s finding a home in the enterprise too.