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
Choosing between SDN open source and vendor-provided options is easier when you know some of the available choices. Industry analyst Lee Doyle lists ...continue reading
How can your organization take advantage of SD-WAN? Networking expert Lee Doyle explains how SD-WAN adoption can transform your WAN, and why you ...continue reading
It might come as little surprise, but the two primary options for NFV orchestration platforms are open source or vendor-supplied options. See who's ...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.