Original URL: http://www.theregister.co.uk/2013/04/18/cerf_endorses_sdn/

Vint Cerf endorses software-defined networks

Is this the fall of the stupid switch?

By Richard Chirgwin

Posted in Networks, 18th April 2013 00:03 GMT

One of the reasons for the rise of the Internet was that it was stupid: by throwing buckets of bandwidth at any problem, and attaching the intelligence to the network edge, it could ship bits around vastly cheaper than telco carrier networks.

That competition was documented back in 1998 in David Isenberg's famous paper, The Dawn of the Stupid Network, which dismissed the “intelligent network” as a “marketing concept for scarce, complicated, high-priced services”.

Now, however, even one of the fathers of the key TCP/IP protocol suite, Vint Cerf, seems to be arguing in favour of returning to a smarter network. In a speech given to the Open Networking Summit in Santa Clara, California, and reported by Slashdot here, Cerf endorses software-defined networking's (SDN) separation of the data plane and the control plane.

That separation means that forwarding decisions – the control plane – can be abstracted away from the switch elements and hosted in external (and more generic) servers.

“I wish we had done [the separation] in the Internet design, but we didn’t … In a very interesting way you have an opportunity to reinvent this whole notion of networking.”

The separation has another implication, however, which isn't lost either on vendors or carriers. The abstraction of the control plane into software is also seen as an opportunity to pull service creation and definition back into the network, away from the elements – giving carriers a chance to recoup some of the value lost when they were turned into big, dumb bit-pipes.

Back to Cerf: speaking to the Open Networking Summit, he noted that the emerging market meant SDN was currently suffering from fragmentation and needs at least some kind of movement towards standards and interoperability.

“As you get to the point where you want to have something big happen, spend some time working on getting agreement on standards,” Cerf is quoted as saying. Standards encourage innovation because everyone can work to the standard, as “happened in the creation of the Internet—and these standards often create a certain amount of stability.

“Stability is your friend in networking environments. If you can’t rely on some stable point in the architecture, you’ll have some trouble in making things work reliably.” ®