Using a network overlay is one way to implement an SDN architecture. An overlay network is a computer or storage network built on top of another network and connected by virtual or logical links. In the context of software-defined networks (SDNs), an overlay network uses virtual links to connect to the underlying physical network (e.g., Ethernet switches or routers).
By submitting your personal information, you agree that TechTarget and its partners may contact you regarding relevant content, products and special offers.
With SDN implementations, the software-defined network can either be built as the logical network (e.g., with a server) or, more commonly, as an overlay on an existing physical Ethernet network consisting of switch and routers.
Physical networks are extremely efficient at moving packets at high speed and high reliability. The challenge that SDN is trying to address, however, is the ability to make the physical network more Agile so it can respond quickly to changes in network requirements -- for example, the provisioning of new compute workloads and virtual machine mobility.
It is likely that initially, the majority of SDN implementations will use SDN to improve the flexibility and operations of an existing physical network -- which would make it an SDN overlay network. As the technology matures, organization may decide to implement "native" SDN protocols as their primary network.
Related Q&A from Lee Doyle
Network expert Lee Doyle explains the status of NFV deployment in 2018 and how open source, 5G and the internet of things can drive future changes. Continue Reading
Most people have experienced poor quality when it comes to real-time network traffic, like VoIP and video. But SD-WAN can help prioritize traffic and... Continue Reading
SDN and intent-based networking share more in common than hype about their promises and potential. Our expert weighs in on how the two technologies ... Continue Reading
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.