Yes, people really are still debating the definition of SDN (software-defined networking)

Thankfully, many speakers at the Open Networking Summit in Santa Clara, Calif., this week agreed on the definition of software-defined networking (SDN): the separation of the control plane and the data plane. But despite the growth of the conference, what people could do with software defined networking wasn’t completely clear, leaving enterprises unsure of what’s possible and what’s not and which vendors can solve which problems.

Bruce Davie, principal engineer at VMware, (s vmw) took the stage with a provocative message: SDN has promised many things, but most of those things are being delivered with network virtualization, and SDN isn’t necessary. Network virtualization, of course, is the preferred term for Nicira, which VMware bought last year for $1.26 billion and subsumed into its own product last month. Davie said he often sees people claiming that SDN can let network administrators do application-level programming of networks, easily provision and manage networks, improve performance and add bandwidth. But Davie has his doubts about that.

After Davie’s address, I ate lunch with a bunch of network engineers from a Fortune 100 company who are getting pressure from executives to lower capital and operational expenditures with SDN. But they’re just not sure what to do. They need to find something fast, but they also don’t want to bring any more risk into their data center. That’s why implementing open-source code on the way from the OpenDaylight Project on top of white-label network gear might not be as good a choice as sticking with expensive hardware with reliable support from a legacy vendor. These guys already hear different definitions from different vendors. When they hear that, no, SDN is not going to make networks programmable, they only become more uncertain of what to choose.

It’s a little easier to see why about half of more than 200 enterprise network administrators surveyed earlier this year couldn’t identify the correct definition of SDN. And so it seems we still are arguing over definitions, that we are still in the hype cycle, that we are still trudging through the FUD phase.