In the alphabet soup of high-tech jargon, most have only a faint idea what 4G mobile broadband really means, except that it’s supposed to be faster than what they get today.

Part of the problem is that all the national carriers say they offer 4G speeds. But what they provide is very different, depending on the carrier.

Rep. Anna Eshoo (D-Calif.) wants to clear things up. She’s introducing a bill Wednesday that would require wireless carriers to spell out what speeds a consumer gets when buying into a 4G data plan.

The bill, called the Next Generation Wireless Disclosure Act, would require carriers to inform customers at the point of sale about the minimum data speeds their 4G networks offer. The carriers would have to explain pricing and coverage areas better. And the Federal Communications Commission would have to provide speed and price information on the top 10 wireless carriers so consumers can comparison shop.

“My legislation is simple — it will establish guidelines for understanding what 4G speed really is, and ensure that consumers have all the information they need to make an informed decision,” Eshoo said in a statement.

Today, Verizon advertises that its 4G network provides 5 MB to 12 MB, but in Washington it only delivers 9.5 MB, compared to 19 MB in Houston, according to statistics by RootMetrics.

In contrast, AT&T says it offers up to a 6 MB per second data connection but actually delivers about 1.5 MB in Washington.

The technology is fairly new and is only starting to be picked up by consumers. Pretty much all the high-tech industry thinks the future is in mobile Internet access and 4G speeds — with devices such as iPads and Droids replacing laptops and computers down the road.

Data plans, meanwhile, are all moving away from all-you-can-eat options. AT&T charges users by how much data they consume and Verizon said Tuesday they will begin that practice in July. T-Mobile slows down users who surpass their monthly caps, too.

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