Arista plans to let users buy its EOS software on a subscription basis — a format similar to an installment plan, aimed at Tier 2 and 3 cloud providers that are hesitant about up-front infrastructure costs.

Today's announcement describes the pricing scheme as a separation of the hardware and software payments for a switch — and from there it's easy to jump to the question, "When does Arista start selling EOS all by itself, on white box hardware?" But that's not what's happening here, and Arista has no white box plans yet. More on that in a bit.

When buying EOS as a subscription, the customer still has to buy Arista's hardware up-front, at list prices that start at around $10,000. But the EOS software purchase becomes a monthly payment of roughly $500 ($6,000 per year). It takes about three years for a customer to pay off the normal EOS price, Arista estimates.

Which brings up a key point: The subscription model assumes you don't keep the switch in place for more than about three years. That's reasonable for the cloud but different from, say, the telecom norm of leaving equipment in place for a decade. Under the subscription model, that Arista switch becomes more expensive the longer it stays on the rack.

So the subscription model isn't for everybody. Its audience is the population of smaller cloud players, the kind that don't operate at Amazon or Google scale.

"They're the ones challenged with building out this infrastructure," since it takes a lot of early investment in infrastructure, says Jeff Raymond, vice president of EOS software and services. They're interested in deflecting some of the switch's price, because the revenues generated by the switch will arrive over the course of months or years, in the form of cloud subscription and service fees.

It's also not being applied to every product — just top-of-rack switches for now, and not the highest-end varieties.

"We do think the traditional model will continue to serve the bulk of our customers," Raymond says.

The subscription pricing for EOS will be available later in the second quarter, Raymond says.

So, when will Arista get into the white box market?

Only when that market gets to be big enough, Raymond says — and that's been Arista's official answer for a while now. White boxes are about a $259 million-per-year market, CEO Jayshree Ullal said during the company's earnings call in February, quoting a figure from Dell'Oro Group. And nearly all of that demand comes from Google and Amazon, Dell'Oro analyst Alan Weckel has said.

"Once the market gets big enough, Arista will consider participating in it when we have customers who want it," Ullal said on the earnings call.

It's a generic position, when you think about it — "we won't sell something that people don't want to buy." But the white-box question is particularly pertinent to Arista because the company initially considered being a pure software vendor.

So while Arista has avoided the blade and virtual-switch markets, it's wired for white boxes. Moving into that market would be "a very small step for us," Raymond says.

Juniper has already taken that step, offering the Junos operating system on hardware built by Alpha Networks. A nudge from the right customer might be all it takes to put Arista in the white box camp, too.

White boxes might not be cool in a mainstream sense yet, but DevOps is. So a bit of Puppet Labs news is tacked onto today's Arista announcement.

Arista already trumpeted its support for Puppet, and for several other applications, with the announcement of EOS+ in December. EOS+ is a version of EOS made to be more programmatic, integrated with applications that can react to feedback coming from the network.

In the specific case of Puppet, Arista also added a native Puppet agent for EOS in February and put an EOS model into the Puppet Forge.

With today's announcement, Arista is enhancing that integration — for example, making Puppet scripts aware of Arista's APIs, so that the scripts can be substantially simplfied.

Arista is also starting up an EOS community, a place on the web where customers can exchange programming ideas and/or communicate with Arista's experts.

In general, the network equipment vendors will probably make stronger overtures to the developer community during the next year or more. Cisco is an extreme example with DevNet, a major program that gets its own corner of the Cisco Live conferences. Arista's EOS community is a move in the same direction.