BBC and P2P Next Test HD BitTorrent Streaming

The EU-funded P2P Next project has started to stream BBC content in true 1080p HD via BitTorrent. The project posted an episode of the BBC’s R&D TV on its technical trial web site this week, with the option to stream it either in regular 480p or full HD-quality 1080p. Users have to first install a plug-in, which is currently only available for Windows.

P2P Next has been working on BitTorrent-based streaming since early 2008, and the project has enjoyed support from a number of European heavyweights. The EU has funded P2P Next with 14 million euros ($20.8 million). The BBC has been an early content partner of the project, and Pioneer has partnered to produce a P2P set top-box prototype. Initial data from the current test is promising, but it also shows there’s still work to be done.

P2P Next is using a technology that’s loosely based on BitTorrent, but optimized for real-time and on-demand streaming. The objective of the current trial is to see whether the project’s adaptation of BitTorrent can scale. P2P Next’s researchers are also using it to experiment with ISP-friendly congestion control, meaning that they’re trying to figure out how to route those P2P video bits without clogging up the tubes.

One the big issues of P2P streaming has always been latency. A little bit of a delay is unavoidable if bits are handed down from user to user, but of course waiting for minutes isn’t really an option for live video. The current P2P Next trial seems to work fairly well in this regard: I only had to wait a couple of seconds until the BBC clip showed up in my browser after I installed the plug-in on my Windows machine, and a quick glance at the test results published in real time on the P2P Next web site show that the average delay is around 8.5 seconds.

A delay like that is too bothersome for on-demand content like the video used in this trial. However, BitTorrent inventor Bram Cohen, whose company BitTorrent Inc. is currently working on its own P2P streaming solution, has argued in the past that any delay greater than 5 seconds is unacceptable for live video. It’s also unclear how the technology would behave under really high demand. At last check, only around 500 people had participated in the test. And the statistics page showed some issues with stalling, with more than 10 percent of all users reporting more than 10 stalls.

Still, the test is remarkable, if only for the fact that it shows persistent interest by broadcasters like the BBC to use P2P technology. We shouldn’t expect the BBC to incorporate this type of technology into its popular iPlayer anytime soon, especially since the iPlayer really only took off after the Beeb ditched P2P downloads for its current web-based streaming model. However, P2P Next is also experimenting with distributing 500 set-top boxes to TV viewers in Europe by the end of this year. The BBC has been trying to move the iPlayer beyond the PC for a while with implementations for the Wii and various set-top boxes. Throw some P2P into the mix to cut down the broadcaster’s bandwidth bills, and suddenly BitTorrent is starting to make a lot of sense for the Beeb.