Comcast Corp. says it will stop targeting BitTorrent on the Internet, according to an announcement to be made today.

Seeking to defuse tensions in a government investigation, Comcast says it will halt its practice of interfering only with BitTorrent file-sharing programs when the Internet congests and slows speeds for everyone.

The Philadelphia cable company also will boost broadband capacity to make it easier to transmit online video and other rich media, it says. At times, BitTorrent accounts for 50 percent of the traffic on the Internet, with 40 million to 45 million users around the globe.

As part of the agreement, BitTorrent Inc., based in San Francisco, will make its free software more efficient and will make sure software developers learn of those efficiencies.

Comcast and BitTorrent, which have clashed publicly for months, are expected to announce the collaborative agreement today. The Comcast-BitTorrent dispute has been a cause celebre among Internet advocacy groups and others who called for greater regulation for an open Internet, citing Comcast.

Kevin Martin, chairman of the Federal Communications Commission, is investigating Comcast's action with BitTorrent to determine if it qualifies as "reasonable" network management. Martin scheduled a second public hearing in the investigation for April 17 at Stanford University, which ratcheted the pressure on Comcast. A prior public hearing in Boston led to headlines when it was disclosed that Comcast paid "seat-warmers" to attend the forum.

It was unclear what impact the agreement would have on the FCC investigation.

"We are thrilled with this," Ashwin Navin, cofounder and president of BitTorrent, said of the agreement. BitTorrent traffic will be treated the same as that from YouTube Inc., Google Inc. or other Internet companies, he said.

Internet management should be "fair, agnostic and disclosed," Navin said. BitTorrent would work through its forums and open bodies to distribute new standards for its software, he said.

It was important that Comcast agreed to expand Internet capacity, because broadband in the United States is falling behind other areas of the world, Navin said. Referring to the clashes with Comcast, he said: "We are not happy about the companies' being in the limelight."

Comcast had said that BitTorrent users hogged bandwidth and distributed pirated video. At first, Comcast said it did not target BitTorrent. Later, it admitted it did.

Tony Werner, executive vice president and chief technology officer at Comcast Cable, said yesterday that the agreement had "an awful lot of promise" and that Comcast would move quickly to implement it.

The cable giant would continue to manage traffic on the Internet, as other network operators do, but without singling out BitTorrent, according to the agreement.

"We are working hard on a different approach that is protocol-agnostic during peak periods," Werner said.

He said Comcast was talking with other Internet operators and had discussions on the issue recently at a conference of Internet engineers in Philadelphia.

Contact staff writer Bob Fernandez at 215-854-5897 or