Desktop voice over IP development with PSTN integration

Our design specification for voice over IP field applications has three main targets: the development and distribution of a free and open source application for voice communications over IP networks; the internetwork of this applications with the PSTN infrastructure without expensive equipments and the technology´s study for future developments. The application, called Ephone, uses a modular development approach in order to allow the use of different protocols, compression and robust audio transmission algorithms. Because of this approach we are creating a development API, interfacing with the current system, that will allow anyone interested in this subject to change the system´s usual operation and also to create new applications related to voice transmission using its platform. We describe an IP voice system and it explains the Ephone´s main features and workflows, questions the robust audio transmission as well as the viability of a voice tool quality in packet networks, particularly IP networks