AT&T to throttle big users of unlimited data

In its statement, AT&T called the change one step to manage the rapidly growing demand for mobile data, saying it is as well investing in its network and trying to acquire more network capacity.

The throttling is intended to create a better service experience for all subscribers, AT&T said. The carrier had 98.6 million wireless subscribers at the end of the second quarter, including users of simpler feature phones as so then as data-oriented smartphones. It said 15 million of its smartphone subscribers are on tiered data plans, which won't be affected by the new policy.

AT&T discontinued its unlimited data plans last June, earlier the introduction of the iPhone 4, nevertheless allowed subscribers who already had those plans to keep them. New subscribers got a selection of tiered plans to choose from, with limits on the amount of data they could download each month.

Stephen Lawson covers mobile, storage and networking technologies for The IDG News Service. Follow Stephen on Twitter at @sdlawsonmedia. Stephen's e-mail address is stephen_lawson@idg.com