One of my readers sent me this question:

Considering I know nothing about anything SDN-related (and considering it seems "SDN" means something different depending to whom you are asking), where should someone with no knowledge of SDN start?

The obvious answer: sdn.ipSpace.net. On a more serious note:

• You might want to start with the question “What is SDN?”, or “which definition of SDN makes sense?”, so the obvious starting point would be the Introduction to SDN webinar (free thanks to sponsors NIL Data Communications and NEC).
• You can also get that same webinar bundled with a few others into Introduction to SDN, NFV and Network Automation (also free).
• Once you’re ready for heavier topics, explore the paid SDN and network automation webinars. You can buy individual webinars, whole tracks, or get access to all of them with ipSpace.net subscription.

Is that all? No, obviously there are plenty of other resources on the Internet, but unfortunately most of them preach the centralized control plane religion (which makes little sense). However, if you found something more agnostic, please write a comment, and I’ll add a List of resources to my SDN page.

Interestingly, it was pretty easy to do that for IPv6, but then that technology can buy a beer even in most restrictive countries these days.