The way to fix this situation in my view is to make the NAT box SIP
aware by building a SIP proxy capability into the NAT box. The designers
of NAT boxes go to great efforts to try to work around applications.
Leave approaches such as STUN to the case where you are dealing with a
My SIP ATA sits behind a iptables based NAT, and I have never had a
problem with it. No STUN either. Symmetric IP Masquerading does the
trick. Then again, it is not a commercial NAT device, just a
function of the iptables firewalling suite in the linux kernel and
associated userland tools.
sleekfreak pirate broadcast
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