Hello,

the signaling shows traffic going from public IP (caller) to private IP (kamailio) then back to public IP (callee). So it is a bit of complex routing if you keep it like this. The best is to get it done working with kamailio, rtpproxy and mcu on their public ip, because they have such already. Then you can think of moving to use some private networks.

Your fourth bullet below is not clear for me: the clients should have visibility to sip server in order to register and call, but you say not, maybe just a typo.

Also, I would recommend to start with latest kamailio 3.3.1 version, 3.2.0 is very old, if you really want that release series, the use latest 3.2.x, not 3.2.0.

Cheers,
Daniel

On 10/9/12 1:36 PM, MARINA SERRANO MONTES wrote:
Hi Daniel:

The network is:
Thank you very much.

Br,
Marina

I attach the sip messages of a call with/without MCU:
...

-- 
Daniel-Constantin Mierla - http://www.asipto.com
http://twitter.com/#!/miconda - http://www.linkedin.com/in/miconda
Kamailio Advanced Training, Berlin, Nov 5-8, 2012 - http://asipto.com/u/kat
Kamailio Advanced Training, Miami, USA, Nov 12-14, 2012 - http://asipto.com/u/katu