FOX Networks worked with Barefoot Networks to demonstrate programmable forwarding plane technology within a broadcast network. Barefoot’s Tofino switch chip ran a P4 program written by FOX, implementing forwarding plane functions. The demonstration was supported by switch maker Stordis.

Increasingly, broadcast networks are converting to Internet Protocol (IP). The packetized Live IP technology gives them the potential to have a programmable forwarding plane in which a switch can manipulate packets and make forwarding decisions. P4-programmable forwarding planes enable use cases that are not possible with fixed-function switching silicon.

Thomas Edwards, VP of engineering and development at FOX Networks, gave this example: He said if you want to have the top two-thirds of a video image coming from a camera and the bottom one-third of the video image coming from a graphics device, you could combine those flows from a program written in P4.

“Before, these are things that would normally have to run on a programmable computer, some kind of middle-box,” said Edwards. In the above example, the traditional broadcast network would need to use a special graphics mixing device. But the programmable Tofino-powered switch with the P4 language offers the potential to eliminate middle-box devices.

Edwards also said the programmable forwarding plane would allow FOX to do rapid flow changes on thousands of flows in an instant. “At the top of the hour, cable networks all need to switch to new channels,” said Edwards. “By having those tables loaded on the switch, we can make a single register change. You can make switching decisions on elements deep inside the packet, rather than the networking layer.”

"We're delighted to collaborate with FOX Networks and Stordis as they showcase the power of P4-programmable forwarding planes, like our Barefoot Tofino series of Ethernet switch ASICs," said Prem Jonnalagadda, director of product management at Barefoot Networks, in a statement. "Barefoot Tofino allows users to define the packet processing functions they want in software using P4.”

The trial between FOX, Barefoot, and Stordis was just a demonstration. But Edwards said broadcast networks are increasingly moving to IP.

“It’s becoming more normal now,” he said. “Most large outside broadcast trucks are being built on an Ethernet platform. FOX Sports was one of the first to build an Ethernet truck. We’re also now using Ethernet and IP for monitoring inside our broadcast plants.”

For Barefoot's part, Jonnalagadda said, "We believe the P4 programmability of Tofino will bring forth new forwarding plane applications for IP production infrastructure, accelerating the adoption of Live IP technology for broadcast media networks."