UPDATE: This story originally included a paragraph describing the history of an Intel chip design licensed by Netronome. Netronome's interaction with P4.org does not involve that product. The story has been corrected to reflect this.

It turns out Barefoot Networks, the latest startup from software-defined networking (SDN) godfather Nick McKeown, is indeed making an Ethernet switch chip, hoping to extend SDN's reach by applying the new P4 language.

Today marks the first time Barefoot is officially revealing details about itself, but for two years, the startup has dropped hints about next-generation switching, and McKeown helped Princeton professor Jennifer Rexford get the P4.org community off the ground.

Barefoot's chip — named Tofino, and due to sample in the fourth quarter — is meant to be an alternative to Broadcom, whose Trident and Tomahawk chips have dominated white box Ethernet switching and have even found their way into designs at ASIC stalwarts such as Cisco and Juniper.

At the same time, Barefoot is hoping to promote the use of P4 in general, even inside those Cisco and Juniper ASICs. In talking with CEO Martin Izzard, the topics of Tofino and P4 tend to criss-cross, as if either one could be considered Barefoot's actual product.

Founded in 2013, Barefoot came into existence because networking is "at a junction point forced by mega data centers; folks who have special needs and are prepared to do aggressive things to serve those needs," Izzard says.

In other words, there's a customer base that's willing to spend some money and entertain radical ideas.

That makes it sound like Barefoot's first market will be in white box switches — off-brand, generic boxes. Facebook, Google, and other cloud giants have been willing to build their own white boxes using Broadcom chips, and it's possible they would welcome a more flexible alternative.

Selling the chip to OEMs — brand-name switch vendors including Cisco — could also be a possibility but will take time, Izzard admits. "The steep part of the ramp will come from webscale folks," he says.

Having said all that — one hardware company did beat Barefoot to the P4 cause.

Netronome has been holding seminars specifically on how to use the P4 language on its network interface cards that it sells, and the company recently released an integrated development environment supporting P4 and C.

"We're actually ecstatic that Netronome claimed it had the first production P4," Izzard says. "One of the advantages of P4 is that it scales across platforms," meaning it's usable on ASICs, network processors, regular microprocessors, and FPGAs.

In the latter case, one company is applying FPGAs to create a programmable forwarding plane: Corsa Technology. Izzard didn't mention Corsa in talking to SDxCentral, but presumably he'd be equally "ecstatic" if P4 were to appear on that platform as well.

So, why make a chip startup? It's a tough road, a sector investors have been skittish to pursue.

The discussions that would lead to Barefoot and P4 began in 2011, and at the time, there was no suitable platform to run the language on, Izzard says.

Moreover, with P4 being implementable on a variety of chips, Barefoot wanted to stand out by creating a particularly high-end device. Tofino forwards a claimed 6.5 Tb/s of traffic, compared with 3.2 Tb/s for Broadcom's top-of-the-line chips.

Barefoot, which now has 80 employees, managed to raise $75 million from investors including Sequoia Capital, Lightspeed Venture Partners, and Andreessen Horowitz — some pretty big names.

It seems likely they were attracted by Barefoot's team. McKeown, a Stanford professor, helped start the SDN craze. He and graduate student Martin Casado were among the founders of NiciraNetworks, which famously got acquired into VMware. (Casado joined Andreessen Horowitz earlier this year.)

Izzard, meanwhile, was a player in Ethernet semiconductors before Broadcom swallowed the market, having worked at Texas Instruments for 21 years. He'd also helped McKeown with an earlier switching startup called Abrizio.

McKeown and Izzard started Barefoot as a joint project between Stanford and TI; when TI lost interest, it gave them the OK to create a startup. TI also licensed them some patents, which at this point make up a minority of Barefoot's intellectual property, Izzard says.

One thing that's changed since Barefoot was founded: Switch-chip startups showing signs of life. Startup XPliant got acquired by Cavium, and Innovium recently raised $50 million in two rounds.