WASHINGTON  Thwarted by the courts, by lawmakers on Capitol Hill and by some of his fellow commissioners, the Federal Communications Commission chairman will try again on Wednesday to devise a new strategy for regulating broadband Internet service providers.

In a speech he plans to give Wednesday in Washington, Julius Genachowski, the F.C.C. chairman, will outline a framework for broadband Internet service that forbids both wired and wireless Internet service providers from blocking lawful content. But the proposal would allow broadband providers to charge consumers different rates for different levels of service, according to a text of the speech provided to The New York Times.

Mr. Genachowski has decided not to use the commission’s telephone regulatory powers to govern broadband Internet service, a move that he proposed in May that would potentially open Internet service to heavier government regulation.

His proposal would also allow broadband providers to manage their networks to limit congestion or harmful traffic.