Software-Defined Networking: Where It Came From and Where It’s Going

The global software-defined networking market, valued at $9.9 billion in 2019, is predicted to grow to $72.6 billion by 2027, a 28.2% growth rate.


Software-defined networking (SDN) solves pain points for enterprises, carriers, and service providers. Using software to control networks, SDN gives operators centralized management and a holistic view, even if the network encompasses multiple physical locations. It also offers organizations a way forward, enabling them to leverage the Internet of Things, cloud, metaverse, and other advanced technologies that can impact a business’s competitiveness.

The Evolution of SDN

Before SDN, the only solution when a customer needed more data capacity or bandwidth was to make significant capital investments in infrastructure. However, as more businesses transformed digitally, it became clear that they needed a better solution.

The idea for SDN isn’t completely original. The fundamental theories of SDN can be traced back to public switched telephone networks where control and data planes were separated to simplify management and provisioning. Engineers used those principles for decades before the thought of applying them to data networks.

As software evolved, telecommunications service providers saw an opportunity to use less expensive commoditized telecommunications hardware connected via software, thus making networks function virtually. This spawned a new field of knowledge known as network function virtualization infrastructure. Subsets of endpoints could now be isolated, either for security reasons or for specific protocol applications.

That control is similar to software-defined networking, which allows businesses to expand their networks and still maintain control over them. It enables them to create policies that apply across the network by providing instructions to every device on how to regulate access to enterprise resources.

SDN also allows businesses to expand without needing to rewire routers, gateways and switches physically. Software-defined WAN blends some SDN concepts in enterprise WAN strategy. SDN enables network virtualization to segment different virtual networks within a single physical network or to bring together geographically separated devices into a single virtual network. Additionally, SDN is a solution to addressing limits on the speed of network growth. SDN allows for increased enterprise control over networks. Businesses can grow, acquire other businesses, and not be limited by certain vendors’ architecture.

SDN Now and in the Future

The global software-defined networking market, valued at $9.995 billion in 2019, is predicted to grow to $72.630 billion by 2027, a 28.2% growth rate. The solutions segment is expected to represent a large share of the market. Solutions make businesses with advanced network, compute, and storage capabilities immediately usable.

Additionally, SDN is a logical solution for enterprises that cannot tolerate long periods of downtime. Engineers can configure the network so that when an outage occurs, the network will automatically reroute and maintain enough connections for business functions to continue. Through this automation, engineers can increase uptime without adding any large expenditures for new hardware. SDN further allows for networks to be automatically scaled up or down as needed so that businesses are only paying for the capacity they need when they need it.

The Future of Software-Defined Networking

SDN is still nascent, and the technology has been applied primarily to cloud-hosted control planes implemented in production networks. But the industry is now beginning to apply SDN to access networks and programmable pipelines used to deliver new data plane features. Implementation of virtual networks and SD-WAN has varied, but traditional networks still outnumber software-defined networks.

Concerns about SDN must be addressed. It is an open-source technology, and while the cost savings it offers are considerable, organizations that adopt the technology will need to find a way to secure their networks adequately.

The adoption of SDN will likely grow as technology improves. However, use cases that have yet to be developed may, in the end, prove to make the biggest impact on how SDN is used in the future. The promise of SDN is the potential features it offers that simply were not attainable previously with traditional networks.

Mike Majewski is the CEO at SEH Technology. He opened the SEH U.S. sales office in Phoenixville, PA, in 2002; three years later Mike became CEO of newly founded SEH Technology, a fully owned subsidiary of the German vendor SEH, a specialist in network printing solutions for more than 20 years. Mike also established the U.S. sales channel and subsequently managed all sales, distribution, and marketing activities for North America. Today, Mike is still responsible for all ongoing sales and marketing processes as well as technical relations with SEH’s OEM partners.