Far-End NAT Traversal White Paper

The goal of far-end NAT traversal is to allow inbound and outbound VoIP calls to succeed in the highest number of cases, even when one or both parties on the call are behind address-translation-enabled firewalls. No requirements on the subscriber-premise’s hardware, software, or firewall should be permitted – the subscriber’s experience should be to simply plug in a properly configured VoIP phone and start making calls.

This white paper discusses the issues that must be considered and the solutions required to achieve this goal. It begins by examining the effects of firewalls in their role as packet admission controlling points, and then looks into the more complicated issues arising from Network Address Translation (NAT) and Port Address Translation (PAT). A broad range of NAT traversal solutions are discussed, including the use of a Session Border Controller (SBC) that includes an external Back-to-Back User Agent / Media Proxy (B2BUA/MP).

Please sign in to access the “Practical Far-End NAT Traversal” for VoIP white paper.