"STUN (Simple Traversal of UDP (User Datagram Protocol) through NATs (Network Address Translators)) is a network protocol allowing a client behind a NAT (or multiple NATs) to find out its public address, the type of NAT it is behind..."
The two main categories of NAT devices are Cone NATs and Symmetric NATs. The difference between these two types is whether the NAT device (i.e. router/firewall) maintains a consistent port mapping between itself and the client machine.
Need a small footprint, standards-based Firewall NAT traversal client to be integrated with your SIP hardphone or your Instant Messaging client? The Paradial RealTunnel client ensures maximum call success rates, and is offered as SDK towards any IM or col