End-to-End Network Security: Defense-in-Depth

Chapter 9. IP Telephony Security

This chapter covers the following topics:

• Protecting the IP Telephony Infrastructure

• Securing the IP Telephony Applications

• Protecting Against Eavesdropping and Other Attacks

Cisco alone has sold more than 4.5 million IP phones and 3 million Cisco Unity unified messaging licenses. The company has more than 20,000 IP Communications customers. IP telephony or Voice over IP (VoIP) deployments are growing dramatically on a daily basis. Consequently, the need to secure IP telephony networks is also growing by the minute. IP telephony security threats generally fall into one of two categories. The first category includes risks that are aimed to hijack listening or unauthorized listening to voice conversations ...