Mobile operators cannot block legitimate domains and services.

Verizon has appealed a ruling by the US Federal Telecommunications Commission prohibiting providers from blocking access to legitimate websites or services. Blocking websites that overload the operator's network, as well as various IP telephony and videoconferencing services, primarily Skype, is now common practice for mobile operators worldwide.

The Federal Telecommunications Commission recently introduced a rule that a carrier cannot prohibit a subscriber from using any website or service unless it has been found to be illegal. Verizon representatives appealed this ruling to the District of Columbia Circuit Court.

According to Michael Glover, Verizon's general counsel, the decision goes beyond the authority granted by Congress and creates uncertainty for the communications industry, developers, investors, and consumers.

But the rules haven't yet been approved in the Federal Register, so Verizon clearly rushed its announcement.