According to Variety, the MPAA is cracking down on two of the biggest peer-to-peer networks used for movie piracy.

Trade org is expected to announce today that it's working with law enforcement authorities in the U.S. and Europe to arrest individuals and groups who run indexing servers for eDonkey and BitTorrent.

A recent study by piracy tracking company BayTSP found eDonkey was the most popular P2P network in November, while BitTorrent is regarded as the fastest growing, particularly for movie downloading.

The move comes several days after the MPAA and RIAA won the right to appeal to the U.S. Supreme Court a lower court decision legalizing decentralized P2P networks (Daily Variety, Dec. 13). But while P2P networks themselves are still legal despite industry efforts to shut them down, indexing servers that help users locate and download pirated content are not.

The fact that the defunct Napster ran such servers, while Grokster and Streamcast Networks, defendants in the Supreme Court case, do not, was cited by lower courts as a key reason why Napster was ruled illegal but the newer networks weren't.

Developers of BitTorrent and eDonkey don't run their own indexing servers. However, many individuals and groups involved in online piracy do, and they're expected to be the targets of the new legal crackdowns.

"If it can be demonstrated they lent substantial assistance to copyright infringement and had knowledge of what they were doing, it's a strong case that fits in line with Napster," explained Michael S. Elkin, head of the entertainment and media group at law firm Thelen, Reid & Priest

Several sources close to the MPAA confirmed the planned actions, although reps for the group weren't talking before today's press conference in Washington, D.C.

Criminal and possibly civil action against those running indexing servers will come on top of the hundreds of suits the MPAA recently began filing against individuals accused of pirating movies.

Along with MPAA CEO Dan Glickman and the org's worldwide anti-piracy topper John Malcolm, BayTSP CEO Mark Ishikawa will be present at the press conference. He'll most likely talk about trends in movie downloading, although the company has not worked with the MPAA in any of its actions.

In addition, Travis Kalanick, CEO of fledgling P2P distribution firm RedSwoosh is set to attend. In an effort to demonstrate MPAA's interest in what it sees as more positive uses of technology, Kalanick is expected to talk about how his firm works with studios to distribute promotional video clips online using P2P technology.

Ironically, Kalanick previously headed P2P network Scour, which was effectively shut down by a $250 billion lawsuit by the MPAA and RIAA.