The industry pretty much knows that Barefoot Networks is developing chips for a new kind of network programmability, even though the startup still hasn't disclosed specifics. In fact, Barefoot hasn't disclosed much of anything about itself.

So it was novel on Tuesday when CEO Martin Izzard spoke at the Open Networking Summit. On a panel about startups and open source technology, he succinctly described Barefoot's goals. Nothing surprising surfaced, but it was good to hear Izzard describe the startup's mission in his own terms.

Barefoot is trying to develop a programmable data plane, he said. That's different from the control-plane approach that software-defined networking (SDN) has taken so far. Barefoot wants to let programmers change the way the network examines packets.

That, in turn, would be a step toward "building a completely protocol-agnostic hardware layer," Izzard said.

P4 would be one possible language for programming the data plane, Izzard said. The language got some publicity at last year's ONS and got a semi-official launch in May.

And it's well known that P4 is closely tied to Barefoot Networks, as Stanford University professor Nick McKeown is a founder of Barefoot and of the P4 Consortium.

One use case would be a more flexible form of network monitoring, where it would be possible to change what factors you're watching for. With "hard-wired hooks" for monitoring, "you'd have to have known was was going to go wrong before you started," Izzard said.

"We also envisage being able to use the programmability to do things like traffic management and flow control. You'd be able to optimize the way the network behaves for your application or your context."

The trick will be in getting people accustomed to programming the data plane. "A programmable data plane is undigestible to all but a few people," said fellow panelist J.R. Rivers, CEO of Cumulus Networks.

Rivers believes that if enough users wanted a particular change to the data plane, they could demand it of vendors, which would then go do the programming work. He sounded unconvinced that there would be much pull from customers themselves to have a programmable data plane.

Izzard actually agreed with Rivers about the difficulty of data-plane programming. Part of Barefoot's mission will be to develop tools to make that task easier — trying to widen the pool of people who could do this programming — he said.