Putting the Brakes on Web-Surfing Speeds

State-of-the-art Web surfing, for all of its breathtaking speed, can be baffling. A favorite page gets hung up. A data-intensive application, like playing a video or downloading large files, stutters or stops. Is it the telecommunications operator? Is it the Web site? Is it the smartphone or the computer? Or just a sign of Internet thrombosis? Krishna Gummadi, the head of the Networked Systems Research Group at the Max Planck Institute for Software Systems, in Saarbrücken, Germany, says the blame often lies with the telecom operator, which is selectively slowing broadband speeds to keep traffic flowing on its network, using a sorting technique called throttling.

In 2008, Gummadi and a graduate student, Marcel Dischinger, developed a free software gauge that detected whether broadband service was being throttled by a network operator. The software, called Glasnost after the Russian word for “openness,” has been downloaded and used by 1.5 million people around the world since then. The latest results, based on 121,247 tests run from January through October, suggest that throttling is being done everywhere in the world. In the United States, throttling was detected in 23 percent of tests on telecom and cable-television broadband networks, less than the global average of 32 percent. The U.S. operators with higher levels of detected throttling included Insight Communications, a cable-television operator in New York, Kentucky, Indiana and Ohio, where throttling was detected in 38 percent of tests; and Clearwire Communications, where throttling was detected in 35 percent of the tests.