Title of the deliverable: Towards a Secure and Reliable VoIP Infrastructure

The increasing interest in telecommunication systems and the wide spreading of computer networks within commercial and scientific field, are going in the direction of a deep integration of phone and data systems into a single network infrastructure. We are particular interested in security issues that arise in such context, thinking, for example, about authentication and billing problems. The available security mechanisms can offer different guarantees but their introduction greatly affect the whole system performances. To guarantee system usability and an efficient resource usage, we propose a design methodology and a framework to evaluate how each security choice affects the whole system performances and help system designers in evaluating the performance-security trade-off.