The U.S. Federal Communications Commission (FCC) is investigating complaints, according to which Google is blocking in some regions of the U.S. calls made through the present, if only in that country, Google Voice VoIP service, and therefore decided to initiate proceedings. The complaints come from a competitive group, AT & T, who says that Google in this way violates the principle of network neutrality. This problem affects all the regions in which the termination rate for calls are particularly high. Termination rates are charged by phone operators for accepting a call from a foreign network and its transmission to the end user. In the U.S., these rates vary regionally.