For the first time ever, this year’s Super Bowl was streamed live online, to the initial delight, and then disappointment, of fans, who experienced poor image quality and delays of several minutes.
The man behind the BitTorrent file-sharing protocol, Bram Cohen, is developing software that could fix such problems. This protocol facilitates the distribution of large files by having users serve up fragments of a file to other users as they download it. This makes it possible to share very large files without a single central server.
Cohen’s company, also known as BitTorrent, is now working on technology that could allow a person with far fewer resources than a TV studio to stream live footage to an audience of millions.
“To this day, most of the live video people consume isn’t over the Internet, it’s over the cable system,” says Cohen. “Cable is very well optimized for sending out live events at a low delay, which has, to date, been very hard over the Internet.”
Cable and over-the-air TV can efficiently target multiple people because viewers can all tune into the same stream of content, but the Internet’s design requires a separate copy to be sent to each person. That makes streaming online video of any kind expensive (even Google hasn’t found a way to make YouTube profitable yet) and live video especially so. Specialized servers and other infrastructure are typically required.
Cohen’s solution, known as BitTorrent Live, could make it possible for almost anyone to offer a live stream to millions. Like the original BitTorrent, the scheme relies on viewers all running software that links into a network that distributes data directly between users, in what is known as a peer-to-peer design, which is much more efficient than every user being served by a central server. A key benefit of the approach is that as more people try to download a file, the network’s capacity to serve that file also grows.
Cohen has been running public trials of BitTorrent Live since late last year, streaming live DJ sets from San Francisco. So far, the system has been able to deliver live video with less than five seconds of delay, although the largest audience so far has been roughly 350 viewers.