IP Telephony with a Personal IP-PSTN Gateway: Architecture and PSTN-Line Sharing Application

We present a novel architecture and methods to enable a user to make IP-to-PSTN voice calls without using a VoIP service provider or their gateways. The architecture is based on a ´personal´ IP-to-PSTN gateway (PIPG) deployed at the residence or business of a user, where both PSTN and Internet service are assumed to exist. The PIPG enables the bridging of a voice call between an Internet endpoint, such as a softphone, and a user´s PSTN line. The architecture includes an external server for registration purposes. We also extend the architecture to support the concept of a PSTN-line sharing (PLS) application in which users´ PSTN lines can be shared by members of a group, analogous to popular peer-to-peer file sharing applications. In PLS, the external server supports a directory to available PIPG as well as intelligence to assign PIPG to incoming calls of members. The blocking performance of PLS is also analyzed