[Asterisk-Users] More NAT questions

[Rudolf Ladyzhenskii]

Hi, all

Still trying to get NAT working.

I have following setup:

PHONE  1 ------ * BOX
                    |
             NAT/Firewall
                    |
                    |
              NAT/Firewall
                   |
                   |
                 PHONE 2

Firewall next to phone 2 has all ports open.
Firewall next to Asterisk has open ports 5060 and 10000:20000. All of those 
are forwarded to Asterisk box.

Both phones succesfully register with Asterisk. (I had to add NAT=yes to 
configuration of PHONE 2 in sip.conf to get this far).
Now, problems:
I can place a call from PHONE2 to PHONE1, but sound path is not established.
Calls from PHONE1 to PHONE2 can not be placed at all. (I assume that this is 
because port 5060 is not forwarded to the phone at NAT/Firewall, but more on 
it later).

Looking at SIP debug info, Asterisk tries to use local address of PHONE2 
instead of its public IP. As a result, no info can be sent to it.

I have tried to install SIPROXD on the NAT/Firewall close to Asterisk box, 
but this did not help.

Now, we have tried to use one of the commercial VoIP service at PHONE2 
location. We had to use their phone and it worked just fine without any 
alterations to NAT/Firewall device. I am pretty sure that they use SIP, so 
they did resolve the problem somehow. Sorry, there is no technical info 
available on this service.

Did anyone succeeded in doing this setup? I know, IAX is a better way, but I 
can not setup many Asterisk boxes.

Basically, I am doing it for a friend. He is working for a small medical 
company. They have number of offices that are not open every day and offices 
are too small to put Asterisk box in each one. There will be 1-3 IP phones 
in each office, except central one. Central one will need Asterisk, the rest 
should be on their own.

Any help is greatly appreciated.

Thanks,
Rudolf