New York - Comcast, the nation's largest cable TV provider and operator of a broadband access service with 12.4 million subscribers, or 20% of the U.S. market, is blocking the file-sharing traffic of some of its subscribers in an effort to manage the large amounts of bandwidth they are using, the Associated Press reported.

After seeing reports of such blocking on DSLreports.com and other forums, the AP tested Comcast's network and found the company is intervening between those uploading and downloading files on the BitTorrent file-sharing network, and terminating some of those connections.

While many ISPs engage in "traffic shaping," or giving less preference to bandwidth-hogging applications like file-sharing, the AP called Comcast's blocking "the most drastic example yet of data discrimination by a U.S. Internet service provider."

Tests were also run on connections offered by Time Warner Cable, Cablevision and AT&T, and the AP found no similar evidence of blocking.

"We have a responsibility to manage our network to ensure all our customers have the best broadband experience possible," Comcast spokesman Charlie Douglas told AP.

"This means we use the latest technologies to manage our network to provide a quality experience for all Comcast subscribers."

"It's their network and they can do what they want," said Paul "Tony" Watson, a network security engineer at Google interviewed by the AP.

"My concern is the precedent. In the past, when people got an ISP connection, they were getting a connection to the Internet. The only determination was price and bandwidth. Now they're going to have to make much more complicated decisions such as price, bandwidth, and what services I can get over the Internet."

Related Links:
http://tinyurl.com/3bw96k (AP)

http://www.comcast.net