BOSTON — Plexxi, a data networking company based in the Boston area, may be the zen startup of data networking — it is both “hot” and quiet at the same time. Many networking pundits and VCs (mostly those who have invested in it) have been talking about the company as the Next Big Thing in data networking, but its marketing approach has been subtle and there’s been relatively little noise about its next product — the Plexxi Switch 2.
The company is busy testing and stacking up racks of the Switch 2 — a networking device that is both optical and Ethernet switch, with four optical ports to handle terabits of optical switching traffic and as many as 72 10 Gigabit (Gbps) Ethernet switching ports in each box — and it’s scheduled to ship in the next quarter. After a chat with CEO and Founder David Husak, a veteran of networking technology, it’s clear the company is laser focused and ready to launch a serious assualt on Cisco’s data-center Ethernet dominance.
This company is only two years old, and it may have one of the more unique optical Ethernet products produced in the last 10 years. In a time frame in which many startups would still be stuck on slideware, Plexxi is already shipping its second-generation product with a radical notion: that it can displace Cisco Systems in the data center with a combined optical and Ethernet switch that can be hooked together in rings to handle massive scaleability for data centers.
In an interview in Plexxi’s Nashua, N.H. office, Husak succinctly described to me why Software Defined Networking (SDN) — to which Plexxi has been closely linked — may be nothing more than a marketing buzzword obscuring an even bigger trend in networking: A huge architectural change in data networking needs. (Editor’s Note: Rayno Report will publish the full interview next week).
Husak — a verbose man with a car-racing habit — does not shy from controversial statements. He went as far as to say that the that Cisco has stifled innovation it networking for two decades now, because the status quo — massive Ethernet switches — is good for sales.
“It’s been built this way because the proposition of the Cisco sales guy was to to buy as much core switching as you could and tier it up,” he says. “This has been a fantastic story for Cisco sales guys and their college finances.”
What’s different now? If I were to boil down Husak’s visions, it’s that data-centers have changed the world, and stacks of overprovisioned Ethernet switches are no longer efficient. Engineers throw a lot of bandwidth at the data centers, because in fact they’re not really sure what’s happening inside of them. This is where SDN comes it — the concept of open, intelligent software than can more easily control the network. But there’s more — there’s also the efficiency optical. Plexxi says that data centers need more optical switching and less Ethernet, and it wants to combine the best of optical switching technology in telecom and plug half of it into the data center, to absorb much of the capacity of the Ethernet switch — which is more expensive technology.
This has yielded Plexxi’s combined optical and Ethernet data-center switch that will allow the high-speed optical switch fabric to create an “express lane” for traffic that needs to move on quicker to its final destination, while preserving an electronic switch that can look at data traffic on a more granular level. The Plexxi 2 is a relative monster, for the data center: Four optical ports based on DWDM (Dense Wave Division Multiplexing) technology yielding 480 Gbps yielding a full-duplex (two-way) mesh optical switching, and up to 72 ports of 10Gbps Ethernet. These switches can then be connected in a large ring to expand the capacity of the network.
For networking technology historians, of course, the concept of Plexxi’s switch is not actually new. Ring networks go back a long way. In the enterprise world, there was IBM’s Token Ring networking in the early 1990s. Later, in optical networking circles, ring “topologies,” in which optical switches are connected in a large ring to surround a city, were used in metropolitan switching architectures for telecom networks.
Optical switching engineers in the late 1990s and early 2000s also proposed many forms of the fast-lane concept. It’s always been a goal of networking engineers to keep as much traffic as possible in the “optical domain” — switching it with light — rather than converting it to electrons, which are more expensive, consume more power, and generate more heat than pure optical switching.
But cloud computing has changed the game by driving the need for more efficient optical technology into the data center. Think of the huge warehouses of servers at Amazon.com, Facebook, and Twitter. Traffic is now moving around mostly between massively scaleable virtual servers, rather than from city to city. The electronic Ethernet switching, which is used to connect servers, generates huge amounts of heat and consumes large amounts of power, so the more you can reduce Ethernet switching, the better.
Husak describes this traffic as “East-West” traffic rather than “North-South.” What’s happening in a data center is that a lot of traffic is moving back between servers (East-West), rather than trying to make a larger hop out of the data center (North-South). So switches should be engineered to handle that change.
“The perponderance of traffic is dominated by East-West,” says Husak. “Many servers in a data center talk to other other servers rather than the outside world.”
“It’s a truth that networks are simultaneously way overprovisioned and way underfunctional,” said Husak. “What sense does it make to keep building networks at large scales when nothing talks to everything? It’s really inefficient.”
If Husack is right, Plexxi is going to really shake up the system. And what about the concept of SDN, to which Plexxi is often linked? Husack says it’s a misnomer.
“What they called SDN then is now called network virtualzation. this is not a new idea because we did it with ATM and VPNs back in the day was the same thing.”
Husak says it’s more important to look at the efficiencies of how the bits are being moved around, rather than talking about the “commoditization” of hardware, which is often not necessarily the case. Husak a more important characteristic of the SDN concept is networking flexibility, so that networks can mimic the virtualized world of the data center.
“We’re not alone, in that SDN doesn’t mean much anymore because it meant everything,”
It’s yet another zen statement in Husack’s pursuit of data center nirvana.