Specifically, Active Networking was an experiment to let users configure the router network. OpenFlow is more about giving a network owner a vantage point to watch over the entire network and issue orders to the troops.
"This is about the owner and operator of the network modifying its behavior," says Nick McKeown, the Stanford University professor who's been spearheading OpenFlow since 2008.
OpenFlow has become a hot topic in data center and cloud networking discussions, and the OpenFlow Lab at next week's Interop will further spotlight the technology. It's a specification whereby an external controller -- software running on a server -- sends routing decisions into the network.
OpenFlow was created so that university researchers could experiment. They could try new types of routing or switching algorithms, or new applications -- turning a subset of the network into a smaller, closed network, for instance. Moreover, they'd be able to do this on a network built of commodity switches. In fact, companies such as Brocade Communications Systems Inc. (Nasdaq: BRCD) see the technology as a way to challenge the hegemony of Cisco Systems Inc. (Nasdaq: CSCO).
If you're not already tired of hearing about OpenFlow, here's what you've missed:
- Carriers and big network owners like Google (Nasdaq: GOOG) recently created the Open Networking Forum (ONF) to champion software-defined networking, with OpenFlow being a key component. (See Open Networking Foundation Formed.)
- Startups Big Switch Networks (whose backers include ex-Cisco executives Mike Volpi, for Index Ventures , and Charles Giancarlo, acting as an angel investor) and Nicira Networks Inc. are basing their businesses on it. (See Big Switch Raises $13.75M .)
- Even Cisco and Juniper are talking about working with OpenFlow, although that might amount to just lip service, says analyst Zeus Kerravala of Yankee Group Research Inc. "I don't know how committed they are. Their competitive advantage has always been closed systems," he says.
Not an AN
As Light Reading readers noted back in March, OpenFlow bears some similarity to the Active Networking movement of the '90s.
And that wouldn't be good, because Active Networking had some big problems. Security was one. Network performance was another, because the effects of users' changes to the routers would be unpredictable.
But OpenFlow is different, and it's already happening in some networks. Enterprise Wi-Fi networks divorce the control plane from the data plane, using one point of control for several hot spots. Telco backbones are at it, too. "A control router will make a decision for all the routers, and then push those decisions out to the routers," McKeown says.
It's true that OpenFlow came from university propeller-heads, but it's caught the attention of big-network owners -- hence, the creation of the ONF by Deutsche Telekom, Facebook, Google, Microsoft, Verizon, and Yahoo. Its first goal will be to create a standardized interface from network equipment to the OpenFlow forwarding plane.
Once that's done, the group will work on higher-level interfaces, McKeown says. For example, there might be some way to create high-priority queries into the network, for grabbing video as opposed to retrieving email information from a database, for instance.
— Craig Matsumoto, West Coast Editor, Light Reading
Interested in learning more on this topic? Then come to the Carrier Cloud Forum, the latest event in Light Reading's Service Provider IT (SPIT) series. Collocated at Interop in Las Vegas, May 9, 2011, the workshop is free for attendees meeting our prequalification criteria. For more information, or to register, click here.