INFINERA UNVEILS ALTERNATIVE TO ALL-OPTICAL NETWORKING

After three years in development, equipment vendor Infinera this week is launching the first optical switching platform to employ integrated photonic microchips, providing an alternative to all-optical networks.

In Infinera's DTN optical switch, which handles 400 Gb/s in a half-rack chassis, the optical-electrical-optical (OEO) conversions that normally would be performed by dozens of discrete photonic components are done in a pair of 100 Gb/s indium phosphide chips. Each transmitting chip does the work of 10 lasers, 10 modulators and a 10-channel multiplexer; each receiving chip contains a 10-channel demux and 10 photodetectors.

Without all the pricey components, the resulting cost per gigabit is “an order of magnitude lower” than competing technology, said Jagdeep Singh, Infinera's president, CEO and co-founder. The switch itself takes up half or a quarter of the central office space required by dense wavelength-division multiplexing gear for the same task. And because the DTN maintains OEO conversions, it offers a level of bandwidth management that all-optical networks don't, and it doesn't require separate regenerators, which all-optical networks do.

“If it works, this is a major breakthrough,” said Infonetics Research analyst Michael Howard. “It's a problem so difficult, most design teams haven't even tried it.”

The high price of photonic components in OEO conversions has been such a thorn in the industry's side that an entire equipment sector was created to remedy it: all-optical networks. Led by vendors such as Corvis, Calient Networks and Xros Communications — and joined more recently by Fujitsu and the recently launched Lambda Optical Systems — most of them used microelectrical mechanical systems (MEMS), an array of tiny tilting mirrors, to redirect light without converting it to electronic signals. That approach eliminates the need for components on both ends, but even it is proving to be expensive. As a result, the market for all-optical networks barely exists today.

“The whole all-optical network paradigm is frankly not relevant to the world where OEOs are cheap,” Singh said. Both he and his CTO, Drew Perkins, hail from Lightera Networks, where they built what would become, through acquisition, Ciena's CoreDirector optical switch. The rest of the team includes “the world's smartest people in the space,” according to Howard.

Key to Infinera's strategy was designing both its chips and system in-house, a rare move that led to broad success for Juniper Networks and Cerent Networks, whose gear became Cisco Systems' popular 15454. The strategy allows Infinera to tailor its chip specifically to a particular system rather than a range of system vendors, which maximizes effectiveness. Whereas most chips in today's state-of-the-art optical integration technology do the work of three or four devices, Infinera's does the work of more than 50.

With 13 investors — ranging from venture capital firms such as Mobius Venture Capital and Kleiner Perkins Caufield & Byers to strategic investors like Juniper Networks and Agilent Ventures — Infinera has raised about $150 million since its inception in 2001. Suited to long-haul, regional and metro networks alike (though probably first applied in the long haul), the DTN switch should be in carrier labs in the third quarter and carrying live traffic before the end of the year, Singh said. That puts Infinera well ahead of Lucent Technologies, for example, which recently began a project to develop an integrated photonic chip in four years.

“I think we have a disruptive technology here,” Howard said of Infinera. “A lot of people have made that claim over the years: ‘We have a disruptive technology!’ But I think in this case, they in fact do.”