Abstract: A method and computerized system for directing voice data transmissions by a gateway server of an Internet telephony service provider between an internal computer system of a registered user and an external device connected to the external network, such as Internet, where the internal computer system is protected by a firewall security system that does not allow transmissions of voice data packets to the internal computer system. The gateway server accepts a request from the internal computer system to initiate exchange of voice data with at least one external device, identifies the user and verifies that sender and recipient are registered with the provider and are currently active and able to exchange voice data.