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The bigger picture​Mar 4th 2010From The Economist print edition​Video on the internet: Why are public broadcasters experimenting with the “peer-to-peer”technology beloved of online pirates?​LAST year Norway’s public broadcaster, NRK, filmed a stunning seven-hour train ride between Bergen andOslo, shot entirely in high-definition video. Over one million Norwegians watched the film on television.But NRK faced a challenge in reaching a larger audience. How could it distribute the hard-drive-busting246 gigabytes of raw footage to a global audience without bringing its servers to a grinding halt? Thebroadcaster made a somewhat surprising choice: it turned to BitTorrent, a peer-to-peer (P2P) internetservice best known as a means of sharing pirated movies and music.Some at NRK worried that using a system associated with piracy would generate negative publicity. ButBitTorrent itself is value neutral. It is a uniquely efficient distribution method that lets broadcasters “seed”the internet with one or two copies of their massive media files. It then relies on end users (called peers)who request the file and receive different pieces of it. To assemble a complete version of the file, thesepeers then share their pieces with each other (hence “peer to peer”). It takes a while, but the broadcasterdoes not need expensive server farms or fat data pipes to deliver massive files to viewers anywhere in theworld.Several other public-service broadcasters have also been experimenting with P2P distribution, probablybecause they are relatively insulated from commercial pressures. In 2008, for instance, Canada’s CBCused BitTorrent to distribute a high quality, unprotected version of a prime-time reality show called“Canada’s Next Great Prime Minister”.The British experience, however, reveals that P2P distribution is no panacea. When the BBC rolled outiPlayer, its television catch-up service, in 2007, it initially relied on P2P techniques to offload the burden ofsupplying so many large files. At the time, the BBC’s Anthony Rose believed that P2P was the only way toprovide the service. Yet one year later, the BBC had switched to streaming content directly from its ownservers. The reason? A 90% drop in the cost of bandwidth.There were other problems with P2P. Many users did not realise that they had become video distributorsby installing iPlayer, and complained about slower computers and upload speeds, or about exceeding amonthly data cap. From an ease-of-use standpoint, there is another drawback: most P2P systems workonly with complete downloads, not with streaming video of the kind on YouTube. And if there is one thingthat unites internet users, it is impatience: multi-hour waits to download an episode of “Top Gear” areintolerable.None of this has stopped the European Union from investing in P2P as a route to the remaking ofbroadcasting. In 2008 it put ?4m ($19m) of funding into a four-year project called P2P-Next. It is anambitious international undertaking backed by research institutes, companies and some broadcasters,including the BBC.Television sets are already starting to stream internet video from companies like Netflix in America. IfP2P-Next has its way, televisions, computers and mobile phones will all support a standardised P2Pnetwork for streaming content distribution in the future. The idea is to create the world’s best videoservice: from anywhere on earth, users can then use a standard protocol to pull up any video, at any timeand on any screen.Despite the hitches, P2P may yet be the right way to do this. Bandwidth may be cheap now, but manyworry that the explosive growth of video, much of it in high-definition formats, could soon clog up theinternet. Traffic from legal online video sites like Hulu, iPlayer and YouTube has surged in recent years,increasing from 13% of all internet traffic in 2008 to 27% in 2009. Furthermore, the current infrastructureof the internet is not suited to the simultaneous transmission of live events to millions of viewers.Johan Pouwelse, P2P-Next’s scientific director, imagines a brave new world for broadcasters in whichinterconnected television sets with P2P sharing can give any television station global reach. Barriers tomarket entry will be low, ensuring healthy market competition, he says. “Satellite gave us hundreds ofchannels―internet television can give us all the free-to-air channels of the globe.”The business model that will support all this, however, is not yet clear. Advertising, the lifeblood of manybroadcasters, is difficult to do globally. And distribution through P2P networks has costs. Manybroadcasters make a great deal of money by selling international distribution rights. Though there may belittle commercial demand for a seven-hour documentary of a train journey in Norway, and so no harmdone by giving it away, the BBC makes lots of money selling programmes such as “Top Gear”. It isunlikely that broadcasters, even in the public sector, would give away for nothing on the internet whatthey might otherwise sell through traditional routes. Until a better reason for using P2P distribution​emerges, it may only be of niche interest to the big broadcasters.

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