PITTSBURGH (KDKA) -- It's called throttling -- deliberately slowing down your access to the internet from your smart phone.
"Throttling is this idea if you consume too much of my bandwidth I'm going to intentionally slow down how much bandwidth you can consume, so you might see web pages loading slower than they normally would," Carnegie Mellon University Professor Michael Smith told KDKA Money Editor Jon Delano.
Making it slower to download data, pictures and video is now AT&T's policy for its iPhone customers who have an unlimited data plan and are heavy users, says Smith, who teaches internet marketing.
"They want to charge you based on the amount of data you use, as opposed to giving you an unlimited, all you can eat buffet."
Unlimited fixed price data plans are gone to new customers at AT&T, Verizon, or T-Mobile -- but those already on them could get throttled and pushed into higher priced plans with limited gigabyte downloads.
Sprint is now marketing its unlimited plan directly to AT&T customers.
"This is the beautiful thing about a competitive market place," notes Smith.
But out on the street some have given up on costly smart phones.
User 1: "Nowadays they are just charging more and more, so I don't even have one. It's not worth it."
User 2: "My plan is like 90 a month. It's just too much. My plan is now 30 a month, and I can use the internet in other places."
Others don't complain.
User 3: "It's one of those things that I'm willing to shell out the green just so I don't have to worry about it."
And while AT&T is the bad guy today, all smart phones will be affected eventually.
Smith: "When you have a limited resource and a lot of people get access to it, something's gotta give."
Delano: "Prices go up?"
Smith: "Prices go up."
What really irks people about AT&T's throttling is that it occurs all the time -- even at 2 a.m. when there's plenty of bandwidth.
Verizon throttles, too, but only when their local cell tower is so congested that it cannot accommodate all the downloads.
T-Mobile starts throttling when a user hits five gigabytes.
For now, Sprint says it's not throttling at all.
(TM and © Copyright 2011 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2011 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)
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