Even modest Internet users may hit usage caps

Several Internet service providers are moving to curb the growth of traffic on their networks -- or at least make the subscribers who download the most pay more. This could have consequences not just for consumers -- who would have to learn to watch how much data their Internet use entails -- but also for companies that hope to make the Internet a conduit for movies and other content that comes in huge files. Cable companies have been at the forefront of imposing and talking about usage caps, because their lines are shared between households. In a sense, caps on Internet use are no stranger than the limited number of minutes a cell phone subscriber gets each month. Internet use varies hugely from person to person, and service providers argue that the people who use it the most should pay the most. But the industry hasn't worked out where to set the limits, or how much to charge users who exceed them. Fearing a customer backlash, most providers are setting the limits at levels where very few would bump into them.