Dear, I find that stun and symmetric nat can not work together , but some big sip providers like sipgate or fwd, added stun settings to their ata as default without, any question about customer's nat type.
where is the key ?
El Thursday 12 June 2008 08:59:55 Pezhman Lali escribió:
Dear, I find that stun and symmetric nat can not work together , but some big sip providers like sipgate or fwd, added stun settings to their ata as default without, any question about customer's nat type.
where is the key ?
AFAIK a device doing STUN test discovers the type of its NAT and returns a value to the application invoking it (the ATA). If the ATA receives "Symmetric NAT" when doing he STUN test it cannot set public IP:port in the SIP messages since the ANT type will make them not working.
So, it's a device decission wherever to use STUN or not depending on the STUN test result. For example Twinkle or Ekiga refuse to set the public IP:port discovered via STUN test if the result of the test is "Symmetric NAT".
So if a device (an ATA for example) does STUN test and receives "Symmetric NAT" it shouldn't apply STUN to send requests.
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Iñaki Baz Castillo -
Pezhman Lali