The proposal also excludes services that broadband providers may create. These services, the companies said, would have to be “distinguishable from traditional broadband Internet access services and are not designed to circumvent the rules.” Mr. Seidenberg said that, for example, the Metropolitan Opera might decide to stream its performances in 3-D through such a service because it would otherwise require too much bandwidth.

Mr. Schmidt said Google had no plans to develop these types of online services.

But some expressed fears that this exception could let companies bypass open-access regulations. For example, an online video start-up could create a competitor to YouTube that did not run on the public Internet and would pay for faster connections to viewers. As those types of payments grew, the access companies might have less incentive to invest in Internet capacity, pushing more content providers to these special services and creating alternative networks that look similar to cable TV.

Jason Hirschhorn, a former president of MySpace and a former executive at MTV Networks, said more questions about the proposal needed to be answered, since the exceptions for new services could be interpreted as “just another way of going against net neutrality.”

“Imagine a world where ABC, Comedy Central, MTV, any of these brands, were on some other network, and then there was this open Internet,” he said.

Google and Verizon stressed that their plan was not a business deal, but was a policy proposal that both companies intended to follow and that they wanted the Federal Communications Commission to review. The F.C.C., which since June had been convening meetings of Internet companies, carriers and public interest groups to try to come to an agreement on access issues, called off the talks last week after reports that Google and Verizon had come to a private agreement.

One F.C.C. commissioner came out against the proposal. “Some will claim this announcement moves the discussion forward. That’s one of its many problems,” the commissioner, Michael J. Copps, said in a statement. “It is time to move a decision forward  a decision to reassert F.C.C. authority over broadband telecommunications, to guarantee an open Internet now and forever, and to put the interests of consumers in front of the interests of giant corporations.”

Image Eric E. Schmidt, Google’s chief. “The next two people in a garage really do need an open Internet,” Mr. Schmidt said on Monday. Credit... Matthew Staver/Bloomberg News

Jen Howard, a spokeswoman for the F.C.C., said that it would not immediately comment on the proposal, and that the views of commissioners did not reflect those of Julius Genachowski, the F.C.C. chairman.