The Signaling System 7 (SS7) is the control network used by public telephones all over the world. Having been designed in an era in which few large telephone companies controlled the entire network, SS7 was designed with no security in mind. However, due to the telecommunications deregulation act, liberalization of economies, and the convergence of telephone, IP, and wireless networks, the number of interfaces to SS7 has increased. Author discusses how new players in the market and numerous entry points between SS7 and other networks have brought many vulnerabilities. This book analyzes one such interface existing between the SS7 and IP networks where the inter-signaling can be exploited from either side to disrupt the services provided on the other side. The topics in this book include: SS7 Network Security, SIGTRAN (SS7 over IP) Security, IP Telephony Security.