Posted by: Shamus McGillicuddy
Cisco, data center networks, Networking, openflow, Plexxi, software-defined networking
When Cisco introduced its Open Network Environment at Cisco Live last week, Cisco executives spoke about the importance of northbound APIs, leveraging the intelligence of switches and routers to supply information to the orchestration layer so that it can make better decisions about how to program the network.
Now Plexxi Inc., a stealthy, software-defined networking start-up, is emerging with a similar message. Plexxi is being vague on the details of its technology but it’s lifted the curtain on some of its marketing message this week. It’s calling its approach to software-defined networking Affinity-Driven Networking.
Plexxi is also hinting that its software-defined networking technology extends to the physical layer of an optical network, allowing a network manager to provision bandwidth by manipulating the wavelengths of optics.
Mat Mathews, co-founder and vice president of product management at Plexxi, said his company is starting a limited private beta with select customers who have been working closely with Plexxi on the development of its products. Mathews describes Affinity-Driven Networking as an integrated software and hardware solution consisting of a a top-of-rack network switch and a software-based controller. Although Mathews describes the product as a software-defined networking (SDN) solution, he said Plexxi is not using OpenFlow.
Plexxi customers will be able to build out an entire data center network using only the company’s top-of-rack switches and its software, although customers will have the option of integrating a network domain built with Plexxi technology into an existing legacy ntwork.
Mathews said Plexxi is looking beyond the decoupling of the control and forwarding planes that other SDN vendors champion in order to focus on a neglected issue in the data center.
“Networks are fundamentally disconnected from applications and application workloads,” he said. “We can use tools and software to understand application workloads in a data center. The first part of Affinity Networking is getting an understanding of those workloads and what they require. The second part is building a physical network that can implement these workloads exactly with the direct requirements we understand from either the orchestration tools, the applications themselves or the data center operator.”
So just how does Plexxi deliver a network that is tailored to the needs of application workloads? The company isn’t sharing too much information on that, at least until its products become generally available at the end of this year or early next year. But Mathews did drop some hints.
“We’re leveraging some optical technologies to allow flexibility in how we interconnect racks together without the overhead traditionally associated with the aggregation and core layers [of a data center network]. We can connect racks directly together and enable direct east-west capacity. Servers want to talk to each other, so our physical topologies are optimized for east-west traffic. And we use software-defined networking to flexibly orchestrate that bandwidth based on where it’s actually needed.”
Plexxi’s secret appears to focus on the physical layer of the network stack. The company is virtualizing the physical layer with optical technology somehow.
“We set out to build a network where you can ‘move the wires,’” he said. “That’s where we brought in optical technology, because we can use things like wavelengths and lambdas that are provisioned in software and say, ‘OK, this rack needs to be connected to this rack. And it doesn’t just need a 20 gigabit connection. It needs a 100 gigabit connection.’ Those kinds of dynamic capacity issues are only possible where you get down to virtualizing the physical layer. Optical technology allows us to view those physical layers as wavelengths of light.”
“We can move capacity by changing the way wavelengths of light are distributed across the network,” he said. “Therefore, we can say, ‘You need 20 gigabits now. We’ll take the 10 gigabits you’re not using over here and put it there. That’s not possible today with just a [SDN] flow table.”