The epiphany came last summer. Listening to a Yale doctoral student describe how peer-to-peer networks could cut Internet congestion, executives at Pando Networks realized they might no longer be an enemy of Internet providers—and maybe even be a friend. "It seems so obvious now," says Robert Levitan, CEO of Pando, a peer-to-peer company. "It wasn't then."
In a matter of months, a remarkable turnaround has occurred: The bad boys of the Internet are now seen as among its saviors. Peer-to-peer file sharing, in which end users link their computers using software like Napster and BitTorrent for downloading large files, was long seen as a threat to Internet providers, content providers, and the Internet itself. "All of a sudden, we're seen as good for the networks," Levitan says.
The change comes as Internet providers feel rising heat from several sides. First is the increasing popularity of video on the Web, which sends huge files moving across the Internet and threatens to clog it for everyone.
"The network was never designed to support video," says Lawrence Roberts, a scientist who helped launch the Internet in the 1960s. Peer-to-peer networks get around the limitations in a way that floods the network with more data than it was designed to handle. Left unchecked, the peer networks will overwhelm any efforts to expand broadband capacity, Roberts says.
Yet, when Internet providers tried to block peer-to-peer software, they generated an outcry from federal regulators and lawmakers. Critics say broadband providers like Comcast and Verizon are targeting video download to protect their other business of selling cable TV channels. Cable and telephone companies fear new "net neutrality" laws could hamstring their ability to manage their networks. They're desperately seeking what Douglas Pasko, senior technologist at Verizon, calls "industry solutions to industry problems."
Embracing peer-to-peer is more than a case of "can't beat them." The research by Yale student Haiyong Xie argued that, if managed properly, peer-to-peer networks could in fact benefit the Web with faster downloads and less congestion. Pando and Verizon soon launched a group to study how peer networking might ease data flows.
The initial results have been nothing less than "phenomenal," according to Verizon's Pasko. Download speeds jumped several fold, while network costs fell. In short, peer-to-peer is "no longer the dark-alley distribution system for unauthorized file sharing," the company said in a press release.
The study group now includes about 60 companies, including numerous peer-to-peer vendors and other large Internet providers such as Comcast and AT&T. It operates under the Distributed Computing Industry Association, which is made up primarily of peer networking companies.
Some content providers, meanwhile, already understand that peer-to-peer can help distribute their works more quickly. Movie studios have inked deals with Vudu, which runs a proprietary peer-to-peer network on the Internet to deliver high-quality videos to homes, and BitTorrent itself offers legal downloads for sale on its site.
But until the Yale research, Levitan at Pando says peer-to-peer companies could only hope to "play nicely" with Internet providers. Pando in 2006 launched new peer software as an effort to commercialize the concept. It had emerged in the 1990s in file-sharing networks such as Napster and Grokster, and got a boost with the release of BitTorrent in 2001. BitTorrent dramatically speeds downloads by pulling bits of files simultaneously from numerous end-user PCs.
By opening up those multiple streams, the new generation of peer-to-peer networks fill end-user pipes. Each connection gets pushed to capacity. That's well beyond the occasional and episodic streams that come from Web surfing or E-mail. Networks quickly get strained under the load. Most peer-to-peer software also randomly links computers around the world, sending those streams on long-distance journeys through many pipes.
To shorten the connections in recent tests, Xie and colleagues at Yale obtained maps of how Verizon and other operators had built their networks. That allowed them to link nearby computers for peer-to-peer downloads. The shorter hops meant faster downloads and reduced traffic across the Internet.
Pando Networks provided software for the tests. But Levitan says any peer-to-peer company can use the same sort of approach, if it knows the maps to Internet networks.
Still, some advocates of an unencumbered Internet fear the new approach will favor some peer networks over others. Many argue that the broadband providers profit from broadband fees and don't invest enough in added capacity.
"The answer to this problem is not to ration access to the engine of our economic growth," Sen. John Kerry, the Massachusetts Democrat and former presidential candidate, wrote in a recent op-ed piece. "The answer is to obliterate the argument altogether by building additional capacity."
But burgeoning peer networks would quickly consume any new capacity, says Roberts, the Internet pioneer. His latest company, Anagran Inc., is starting to sell network gear that will help Internet providers slow the flow of data to ease congestion. New technology enables Anagran to slow all traffic, rather than forcing Internet providers to target specific uses such as peer networking.
System strains will require a number of technologies to fairly distribute available bandwidth, says Levitan at Pando Networks. "We do not think peer-to-peer alone will solve the problems." He's just basking in being part of the solution, and not the problem.