One essential element in managing traffic while ensuring security is the traversal of the network address translation device (NAT) and of the firewall. NAT helps to ensure security since each outgoing or incoming request for an Internet Protocol address must go through a translation process that also offers the opportunity to qualify or authenticate the request or match it to a previous request.

For that reason, businesses seeking to deploy a Voice over IP infrastructure must therefore ensure proper traversal of both NAT and Firewall, which can be accomplished by either integrating an application level gateway (ALG) or by using STUN, enabling the Simple Traversal of UDP through the NAT.


Though securing VoIP calls brings with it a set of new and often unique challenges, businesses should give as much serious consideration to securing their voice traffic as they do to their data today. Voice traffic will always account for a considerable portion of a business’ communication, and as systems transfer from the traditional PBX to the Internet voice will increasingly become an attractive commodity for interception by third parties. Whether malicious in the form of eavesdroppers and spoofers or simply distracting in the shape of unwanted content such as voice spam, the damage to a business whether financially or to its reputation could be devastating, so now is the time to be aware and seek a proactive solution – don’t let them steal your voice.