Secure Voice Encryption

A VoIP VPN combines Voice over IP and Virtual Private Network technologies to offer a method for delivering secure voice. Because VoIP transmits digitized voice as a stream of data, the VoIP VPN solution accomplishes voice encryption quite simply, applying standard data-encryption mechanisms inherently available in the collection of protocols used to implement a VPN.

The VoIP gateway-router first converts the analog voice signal to digital form, encapsulates the digitized voice within IP packets, then encrypts the digitized voice using IPSec, and finally routes the encrypted voice packets securely through a VPN tunnel. At the remote site, another VoIP router decodes the voice and converts the digital voice to an analog signal for delivery to the phone.

Other advantages

Security is not the only reason to pass Voice over IP through a Virtual Private Network, however. Session Initiation Protocol, a commonly used VOIP protocol is notoriously difficult to pass through a firewall because it uses of random port numbers to establish connections. A VPN is one solution to avoid a firewall issue when configuring remote VoIP clients. The VPN virtually moves users inside the same network local as the VoIP server.