Most data networks could be faster, more energy efficient, and more secure. But network hardware—switches, routers, and other devices—is essentially locked down, meaning network operators can’t change the way they function. Software called OpenFlow, developed at Stanford University and the University of California, Berkeley, has opened some network hardware, allowing researchers to reprogram devices to perform new tricks.
Now 23 companies, including Google, Facebook, Cisco, and Verizon, have formed the Open Networking Foundation (ONF) with the intention of making open and programmable networks mainstream. The foundation aims to put OpenFlow and similar software into more hardware, establish standards that let different devices communicate, and let programmers write software for networks as they would for computers or smart phones.
“I think this is a true opportunity to take the Internet to a new level where applications are connected directly to the network,” says Paul McNab, vice president of data center switching and services at Cisco.
Computer networks may not be as tangible as phones or computers, but they’re crucial: cable television, Wi-Fi, mobile phones, Internet hosting, Web search, corporate e-mail, and banking all rely on the smooth operation of such networks. Applications that run on the type of programmable networks that the ONF envisions could stream HD video more smoothly, provide more reliable cellular service, reduce energy consumption in data centers, or even remotely clean computers of viruses.
The problem with today’s networks, explains Nick McKeown, a professor of electrical engineering and computer sciences at Stanford who helped develop OpenFlow, is that data flows through them inefficiently. As data travels through a standard network, its path is determined by the switches it passes through, says McKeown. “It’s a little bit like a navigation system [in a car] trying to figure out what the map looks like at the same time it’s trying to find you directions,” McKeown explains.
With a programmable network, he says, software can collect information about the network as a whole, so data travels more efficiently. A more complete view of a network, explains Scott Shenker, professor of electrical engineering and computer science at the University of California, Berkeley, is a product of two things: the first is OpenFlow firmware (software embedded in hardware) that taps into the switches and routers to read the state of the hardware and to direct traffic; the second is a network operating system that creates a network map and chooses the most efficient route.