Washington- “Peer to peer” networks such as Kazaa could prevent people from downloading music, movies and other copyrighted material if they had the desire to do so, media and technology experts said Tuesday.

Kazaa, Morpheus and other P2P networks are hailed as revolutionary technology that allows people to swap any sort of digital material directly, but the services have drawn criticism for their ability to make copyrighted material and hardcore pornography widely available for free.

In a letter to Congress, Titan Media, an adult-video company said that Kazaa’s parent company, Sharman Networks, had the ability to monitor activity on the network and could stop copyright violations if it wished.

Titan’s claim was backed up by two independent technology experts, who said such filtering technology exists and could be implemented easily and affordably.

“If you’ve got computing power to do the searches, you can also use that computer power to do that filtering directly,” said Darrell Smith, who oversaw the Morpheus peer-to-peer network when it shared the same technology as Kazaa.

But existing copyright filters can be easily evaded, said a lawyer for Sharman.

Expert witnesses at a trial last year failed to prove that any filtering system could work, said Larry Hadley, outside counsel to Sharman. “When those people were deposed, it turned out to be a house of cards,” Hadley said.

‘Cant’ be done’
Sharman has long maintained that it cannot control content on Kazaa because file-swappers connect directly with each other, not through company-owned computers. Kazaa does contain a filter to allow people to avoid offensive content.

But others said content filtering is already in use.

Titan, which asked Sharman last month to block 1,400 of its movies, said Sharman can closely monitor activity on the network through “spyware” installed on people’s computers and could block those PC from downloading copyrighted files.

Hadley said the company does not have that capability.

Smith, who is now setting up a peer-to-peer network with built-in copyright protections, said Kazaa has had the capability to block content for years.

“All of the mechanisms to be able to do some form of identification and filtering, and also tracking of the files to some degree, was always there in the core,” said Smith, who is now setting up a peer-to-peer network called M-Terra.

The same technology Kazaa uses to recognize songs and download them from multiple sources can be used to prohibit that song from being shared, Smith said.

One California company has already developed a peer-to-peer system that blocks copyrighted songs.

Los Gatos-based Audible Magic has created a copyright filtering system that is used by CD pressing plants and a small college town in Finland that chief executive Vince Ikezoye said can distinguish between different versions of the same song.

The head of a peer-to-peer trade group that does not include Kazaa, said Congress should hold hearings to determine if such filters actually work or if they are simply hype.

“If this unicorn of a program exists in the forest of software, then it is incumbent upon the industries that keep claiming that they’ve made sightings to at least provide video for the evening news,” said Adam Eisgrau, executive director of P2P United.