The security of the telephone network started to be deployed in the forties at the time of the Second World War. The deregulation and the globalization of the telecommunication?s sector opened the door to the evolution of the telephone networks and to their diversification. Although, the evolution of the information technology yields to a converged data and voice network based on IP technology. The security solutions offered within each network provide protection to its services against eventual attacks and hacking. Nevertheless, these solutions are network dependant and does not allow secure interoperable phone call crossing different telephony infrastructure. This paper describes a new security architecture that provides a secure end-to-end voice communication with an abstraction of the underlying telephony platforms.