Internet subscribers

Embarq Corp. has revealed more details about its exploration of a program that tracked Internet subscribers' Web-surfing habits for advertising purposes, telling Congress that it performed the test on 26,000 customers in a Kansas town.

Building on an earlier response to Rep. John Dingell, chairman of the House Energy and Commerce Committee, Embarq CEO Thomas Gerke wrote in a letter late Wednesday that his Overland Park, Kan.-based company chose Gardner, Kan., for its test because it was Embarq's smallest market and near qualified technicians.

Cox Communications appears to be interfering with file-sharing by its Internet subscribers in the same manner that has landed Comcast Corp. in hot water with regulators, according to research obtained by The Associated Press.

A study based on the participation of 8,175 Internet users around the world found conclusive signs of blocked file-sharing connections only at three Internet service providers: Comcast and Cox in the U.S. and StarHub in Singapore.