This article provides a compact and insightful introduction to the important points of SDN.
The problem that SDN proposes to solve is succinctly described in the article in this way:
“Physically, every time one needs to deploy a server, move a server, add more bandwidth or switch resources, they are touching the rack – a task that is fraught with risks of unintended consequences if the wrong cable is pulled or the proper governance models (which dictate the rules and processes around deployment, configuration, security, access, etc.) are not followed.”
The author continues:
“SDN promises to automate much of this and move from physical connections ruling the data communications to smart applications handling the work, by moving some of the routing intelligence down to the server level and removing much of the intelligence for the corresponding layers of switches and routers. Through this strategy (and flattened hierarchy), less intelligent routers and switches can be deployed, implying a significant cost savings for the typical data center. But is that reality?”
This is a good question to ponder. And, not only that, but how long will it take for standards to stabilize so it all works reliably? The article explores these questions and shows how the major existing vendors may respond to the changes.