Updated 3:20 p.m. PDT with comment from MediaDefender and to clarify that individual movie and recording studios, and not RIAA and MPAA, are clients of MediaDefender, and that Dmitri Villard is CEO of MediaDefender parent ArtistDirect and not MediaDefender.
Revision3 has investigated the denial of service attack that kept it offline over the Memorial Day weekend and has concluded that antipiracy group MediaDefender is to blame.
In a blog post on Thursday morning, Revision3 Chief Executive Jim Louderback writes that much of the traffic that bombarded the Web TV network was traced back to MediaDefender. The group has a history of launching DOS attacks against distributors of what they believe to be copyrighted content, he alleges. MediaDefender's clients include all the major recording label and movie studio, but not the RIAA or MPAA.
Louderback says he called MediaDefender and was told that it had indeed been injecting spoof files into the Revision3 network without permission for months as part of its antipiracy efforts to dilute the pool of pirated content online, but MediaDefender denied responsibility for the DOS attack.
It appears that Revision3's servers were overwhelmed by backed up traffic when the company closed a back door that MediaDefender had been using into the network, Louderback speculates.
"Media Defender was abusing one of Revision3's servers for their own purposes--quite without our approval. When we closed off their backdoor access, MediaDefender's servers freaked out, and went into attack mode," he writes.
He notes that DOS attacks are illegal in the U.S. under 12 different statutes and that Revision3 suffered "measurable harm" to its business as it was unable to serve videos and ads through much of the weekend and into Tuesday, and its internal e-mail servers were even shut down.
The FBI is looking into the matter, he adds.
MediaDefender Chief Executive Randy Saaf told CNET News.com later on Thursday that the firm did nothing illegal, did not target Revision3 specifically, and was merely posting spoof files to what it saw as a public torrent index server that had pirated content on it just like anyone can post files to a torrent network.
"We're fans of Revision3," he said. "We didn't know they were running" the index server.
Dimitri Villard, chief executive of MediaDefender parent ArtistDirect, did not immediately return calls or respond to an e-mail seeking comment.