DSL with dynamic IP

[lebenton]

Couple of questions:



1. Just wondering when setting up Quadro behind a NAT router with
dynamic IP, manual NAT traversal can not be used (as IP is dynamic),
then is STUN the only way of NAT traversal?



2. If all the necessary ports have been forwarded from the NAT router
to the Quadro (eg. SIP & RTP), and I disable NAT traversal will
inbound and outbound calls via VoIP still function?



I'm asking only because I have a few clients with above DSL environment
(dynamic public IP and STUN as NAT traversal) and their SIP
registrations are failing from time to time because of "blocked UDP" in
the SIP status...

[davrays]

Hello Peter,


1. Yep, if your NAT router has dynamic IP and is not SIP-aware, then the only way to pass through that is to enable STUN (it automatically checks for router IP change every 5 minutes).


2. No, even if you forward all necessary ports to Quadro, you'll anyway need to have NAT traversal enabled ( you can use manual settings, if router IP is static; otherwise use STUN).


The reason why you have to enable the NAT traversal, is the following: SIP packets contain IP addresses in the message body, and routers (if they are not SIP-aware) don't modify them. Thus, for these packets to be correctly understood and handled by the remote destination, you have to tell Quadro to put router's IP/port in the SIP message instead of Quadro's own IP/port. For that you enable the "NAT traversal" and specify the IP/port, which Quadro will put into SIP message body.


Thats it.

[lebenton]

Thanks for the explanation David.



Are you able to give a brief explanation on why "Blocked UDP" occurs
when STUN is used as NAT traversal method? Or is this more of a TSS
question.

[davrays]

Yes, that one smells like a TSS question. Without logs it is difficult to tell anything on that. From my experience I can just remember that something like that happened in older versions, but the problem should have been fixed... Edited by: davrays