Dubbed Publius after one of the founding fathers' Federalist Paper pseudonyms, the system promises to be one of the strongest tools yet designed to protect anonymous publishing online. The software allows anyone with a Web browser to post a file online, with almost no fear of being traced or of having the content removed from the system without permission.
The network adds to a growing number of network technologies designed to protect content from interference by corporate or government forces.
All of these systems have come under fire from critics who charge they could be used by criminals to exchange information or to post dangerous content online such as bomb-making instructions or child pornography, for example. Ideas for trimming back online anonymity have emanated repeatedly from circles such as record executives and international policymakers in recent months.
But the AT&T developers say those risks are worth taking, in order to protect free speech.
"The ultimate kick for us as developers is if some organization such as Amnesty International starts to refer people to our systems," said Avi Rubin, the AT&T Labs researcher who is leading the project. "We'd like to see it used in the real world, by real world people who can't express their ideas."
Official announcement of the launch will come tomorrow, according to an AT&T Labs spokesman.
Not a Napster
Because it allows free distribution of files online, without any checks by copyright owners or law enforcement, Publius has been talked about in the same breath as Napster, Gnutella and Freenet.
But the designers hope this won't be the focus for the system and have built in a few safeguards.
At least in its first release, the system will accept documents only 100 kilobytes in size--much too small to accept an MP3 or video file.
And unlike Napster, the Publius system does not have a search feature. Easy searches are partly what have made file-sharing systems such as Napster so popular so quickly.
In order to reach a file, a Publius surfer must have access to the file's complicated URL. The Publius project will provide a list of files it considers interesting, but this will not include music, pornography or anything else deemed "uninteresting."
"We don't view this as censorship," Rubin said. "We view what we're doing as a directory for things we think are interesting. For now, people publishing content on the system will have to email URLs and descriptions of their files to be included, although a search feature might be added in a later version, Rubin added.
That's been enough to win praises from anti-censorship groups, some of whom are actually hosting Publius servers during the trial project.
"We think the way this system is set up goes a long way towards helping individuals voice their opinions and protecting democratic values," said Ari Schwartz, a policy analyst with the Center for Democracy and Technology, a Washington, D.C.-based lobbying group. The center is one of the groups hosting a server for AT&T's trial project.
Rubin says AT&T has supported his project completely--an important factor given an environment where America Online shut down a similar internal development effort that produced the Gnutella file-swapping technology.
The Publius system can be compared to a jigsaw puzzle, in which the entire picture can't be seen until all of the pieces have been put together.
When a document is published on the Web using Publius, the software scrambles the file using nearly unbreakable encryption technology and then distributes this jumbled set of data to a large number of Web servers in the network.
In order to recreate the original document, a reader must put together a predetermined number of "shares" or "keys" to unlock the document. These keys are found inside the URL, or Web address of each published document. Each URL might contain a coded reference to 10 or more Web servers that act as keys; if three or more of these can be found the document will be unlocked. If not, then the document is lost.
This system allows a large number of the servers hosting the document to be shut down without blocking the document's retrieval, as long as the minimum number of keys can be found.
In the initial test of the service, AT&T Labs has attracted about 40 volunteers to host Publius servers and plans to reach about 10,000 files. The number of servers will expand later as the system works into a final release.