Gateway and method for linking a packet-based IP network to a switched or PSTN network in which the gateway first queries a receiving terminal to determine if it is IP enabled and if so uses IP tunneling

摘要

Method for transmission of voice over Internet telephone conversations (VoIP) using an IP gateway to link a packet IP network to a convention (PSTN) telephone network. The first time a connection is made to a particular terminal in a PSTN network the gateway determines if tunneling of IP packets over the network is possible. If so, communication is henceforth via IP packets. If IP tunneling is not possible the gateway acts as an information converter for converting information between different protocols and tunnels as necessary. An independent claim is made for a device, especially an IP gateway for linking packet and switched telecommunications networks.