But just what is SDN? This article from Kurt Marko at Information Week seeks to cut through all of the buzz surrounding software-defined networking and get to the most important questions. Following are the questions that Marko seeks to answer accompanied by important excerpts from the answers he gives:
1. Just what is SDN?
"SDN is nothing more than the separation of network data traffic processing from the logic and rules controlling the flow, inspection, and modification of that data ..."
2. Why all the excitement now?
"Just like server virtualization, network fabrics and clouds, SDN is a new approach to solving real problems ..."
3. How does SDN change my network? What's different?
"From a topological standpoint, SDN needn't change your network at all, although it can make wiring up very wide, non-blocking, flat, two-tier "fat tree" networks replete with VMs and virtual NICs much easier ..."
4. Is SDN just a switching technology or is there more to it?
"The initial focus of OpenFlow has been on software-controlled switching, because the network controller is essentially a server-based application ..."
5. Which vendors are pushing SDN?
"The most visible SDN advocates are members of the Open Networking Foundation (ONF) ..."
6. Are there any standards yet?
"Yes, for OpenFlow. The ONF has two standards: there's the OpenFlow Switch Specification 1.2(PDF) and OF-Config 1.0(PDF) ..."
7. What do critics say about SDN?
"OpenFlow skeptics point out that we're too early in the technology's lifecycle to make any useful assessments of its value, impact, or longevity ..."
8. Where are we in the SDN technology life-cycle?
"Although SDN is in its infancy ... there were plenty of OpenFlow-compatible products on display at Interop ..."
Chances are that, if you're trying to get your bearings in this new world of SDN, your questions are answered in this FAQ. For a more in-depth introduction to SDN, see Eli "The Computer Guy" Etherton's video "Introduction to SDN" here.