Bringing out the advantage that the Google Voice service has vis-à-vis services of other phone companies, AT&T – in its letter to the Federal Communications Commission (FCC) – has said that Google’s Voice blocks certain ‘premium-rate’ phone numbers, operated by rural carriers, for which other carriers have to shell out unusually amounts to the rural phone companies.

Noting the while it is obligatory for carriers like AT&T to put through the high-cost calls to these numbers, thereby entailing yearly costs running hundreds of millions of dollars, AT&T pointed that Google Voice can easily avoid such calls from its long-distance lines to local networks run by other operators.

Further, adding that Google is clearly violating the same net neutrality principles that it overtly claims to support, AT&T said that going by the FCC policy says entitles consumers to competition among networks, Google Voice should comply by the guidelines laid down for its traditional phone service counterparts.

Meanwhile, defending Google’s Voice service, the company’s lawyer Richard Whitt said on the Google Public Policy Blog that Voice being a free, web-based software application is not subject to common carrier laws.

Whitt wrote: “Google Voice's goal is to provide consumers with free or low-cost access to as many advanced communications features as possible. In order to do this, Google Voice does restrict certain outbound calls from our web platform to these high-priced destinations.”