Comrex BRIC-Link II, Руководство по эксплуатации продукта

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STUNNING SUCCESS
Another technique for working around the SIP-Router issue is by using a protocol called STUN . This can be enabled
in Comrex codecs in the Advanced EBU3326/SIP op ons and allows for the codec to learn its public IP address. It
does this by contac ng a STUN server on the Internet (the default one is maintained by Comrex) and reques ng its
Public IP. If this op on is enabled, the codec itself will handle the address switching.
Be aware of the “ba ling workarounds” issue, as ports are being translated by the router as well as IP addresses. If
the ALG-enabled router receives an unexpected result in the SIP address
fi eld (as it might if using STUN), it may not
translate ports as expected, and it’s likely that the call will fail. When in doubt, the best technique is to try a SIP call
with STUN turned o
ff , and if the return channel fails, try enabling STUN.
FIX OF LAST RESORT
Finally, there’s a brute-force op on available on Comrex Codecs when STUN ports are blocked by a fi rewall, or
are unusable for some reason. Under Advanced System Se ngs , a fi eld is available called Public IP Override . Any
address put into that fi eld will be pasted into the address SIP fi eld. A user can thus place their Public IP address
(obtainable from many websites via a browser) in this loca on. Keep in mind, the Public IP Address is o en subject
to change over me, so it’s important to remember this change has been made on a codec.