Security of Voip networks

Voice over IP (VoIP) has had a strong effect on global communications by allowing voice, data and images to travel over existing packet data networks along with traditional data packets. The convergence of voice and data in the same network brings both benefits and constraints to users. Among the several issues that need to be addressed when deploying this technology, security is one of the most critical. We give an overview of VoIP and provide UML models of some aspects of its infrastructure, including architectures, protocols and implementation with a corresponding increase in the potential for misuse and basic use cases. We present some possible attacks against VoIP infrastructures and use the taxonomy provided by the VoIPSA (Voice over IP Security Alliance) in aims to define the security threats and vulnerabilities against the VoIP deployment services and users.