Brent Salisbury sent me a link to a fantastic OpenFlow/SDN presentation Scott Shenker did @ Stanford University a few days ago. It’s a perfect introduction to the fundamental ideas behind SDN and therefore a must-see for everyone vaguely involved in networking.
- They got it all wrong in the first iteration (@ 20:00) – it’s rare to see someone being so honest about past misconceptions;
- Network virtualization is the killer app, and SDN is just a means to an end (@ 25:00);
- MPLS was right (@ 32:00) – would love to see the reaction of a well-known SDN evangelist and MPLS basher ;)
- A network should have a complex edge and a simple core, with software switching at the edge (@ 38:00);
- Today’s networks are full of middleboxes which are already x86-based. The functionality of these middleboxes should be moved to x86-based devices at the network edge (@ 42:00);
- Network latency (actually intra-switch latency) doesn’t matter at the edge (@ 49:00).
There’s still a lot of handwaving and missing details, particularly as you move from tightly controlled environments (data centers) to large-scale WAN networks where individual components have to operate independently to be failure-resilient, but they’ll eventually get there.
This would be a perfect place to smugly list my blog posts (going all the way back to 2011) talking about exactly these same things ... but it’s sunny outside and the kids are waiting ;)