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A huge chunk of the U.S. may no longer have “broadband” service soon, if a new plan by federal regulators to change the definition of high-speed access is approved.

Federal Communications Commission Chairman Tom Wheeler proposed Wednesday to increase the U.S. definition of broadband to 25 megabits per second, saying the current definition of four Mbps just doesn’t cut it anymore.

That “dated” standard is “inadequate for evaluating whether broadband capable of supporting today’s high-quality voice, data, graphics and video is being deployed to all Americans in a timely way,” according to an FCC fact sheet about the proposal.

(The proposed 25 Mbps definition would be for downloads, while the standard for upload speeds would be just three Mbps.)

If the FCC adopts the change — which is likely — it means that about 55 million Americans won’t technically have access to “high-speed” broadband service, FCC officials say. Almost half of those households are in rural areas where it has been more expensive to build out high-speed fiber networks. Millions of Americans in those areas rely on slower DSL Internet service offered by phone companies.

Wheeler’s proposal isn’t particularly surprising, given he mentioned several times last year that he thinks most Americans need faster speeds because they’re glued to tablets and other Wi-Fi enabled gadgets at home, watching a lot of streaming videos.

But the fact that, under the new definition, the FCC could again find “that broadband is not being deployed to all Americans in a reasonable and timely fashion” is likely to upset some Internet providers and their congressional allies, since it keeps open the door to more FCC regulations.

Even though a federal court last year struck down the FCC’s last attempt at net neutrality rules, it did uphold the agency’s authority to take actions to ensure all Americans have reasonable access to high-speed Internet service.

Three years ago, the agency concluded that broadband wasn’t available “to all Americans,” which helped prompt the agency last month to require Internet providers that receive government subsidies to offer service of at least 10 Mbps.

As part of the change, Wheeler is asking for suggestions on what else the agency can do to “accelerate broadband deployment.”

One thing that’s likely to come up is Wheeler’s ongoing efforts to preempt state laws that ban or restrict communities from setting up their own broadband services.

Another move the agency may make could come as a byproduct of the FCC’s soon-to-be released rules on net neutrality.

Google mentioned recently to FCC lawyers that regulating broadband lines under Title II of the Communications Act would actually help it expand its new fiber network because it would give it easier access to telephone poles and other public rights of way.