Cost-Effective VoIP Services for Reducing Digital Divide in Developing Countries: Case of Study and Practical Implementation

Digital divide is one of the most relevant emergencies of developing countries. The situation is particularly difficult in central Africa, where wide zones are totally disconnected by any kind of communication services. In these areas (sometimes not very far from big towns) many people are living and critical infrastructures, like e.g. hospitals, cannot communicate with the external world. In this work, we are going to propose a feasible and low-cost solution for installing VoIP-based telephone services in peripheral areas not reached by fixed and cellular networking infrastructures. The proposed solution is based on a Wi-Fi radio bridge connecting a remote disconnected site with a gateway placed in a town. The gateway consists only of a PC connected to the PSTN by a suitable interfacing card. The gateway is equipped with the ASTERISK server, a software tool able at routing VoIP calls to a PSTN, as it would happen if a regular push-button telephone was employed. The system was developed and tested in open field and provided very good results in terms of efficiency and reliability. Such a positive testing phase encouraged developers to propose such kind of solution also for practical installation in interested countries. In particular, low hardware costs, easy of use and totally open-source software availability are regarded by potentially interested users as real strength points with respect to other available commercial solutions.