NATed solutions with no RTP proxies will depend on the client side, not on the server side like in Kamailio. Key things to notice:

1 - Private IPs (RFC-1918) will always be proxied if you don't change the basic template config;
2 - Dual NIC servers require a little bit more knowleadge on Kamailio before you can get it to work properly;
3 - Although you can use some tricky configurations, Kamailio is not a SBC like Asterisk/Freeswitch;
 
Having said that, RTPproxy is just good. I mean, it is really good! If it is not working, then you probably have another problem. So the questions are: Are you running your system on virtual machines? What is your topology? How many NICs do you have? Your Kamailio server is connected direct to the Internet or behind a firewall?
 
All the above questions can strongly affect the quality of your calls.
 
Cheers!
 
Moacir
From: aelsharqawi@live.com
To: sr-users@lists.sip-router.org; miconda@gmail.com
Date: Wed, 20 Mar 2013 02:09:44 +0800
Subject: Re: [SR-Users] NAT & Firewall Issues

Thanks All,

Yes, please if you've an example using nathelper without rtp proxy let us know.

now more than ten days I am trying to get kamailio up & running to bypass NAT & firewall blocking but I couldn't.

After some research I might create a VPN.

so please if you have any working example for NAT and Firewall let us know.

Regards,
Amr

> From: julian_q@hotmail.com
> To: miconda@gmail.com; sr-users@lists.sip-router.org
> Date: Tue, 19 Mar 2013 11:19:49 -0500
> Subject: Re: [SR-Users] NAT & Firewall Issues
>
> Daniel
>
> Do you have a config example using nathelper without rtp proxy?
>
> Regards
>
> Julián
>
>
> -----Mensaje original-----
> De: sr-users-bounces@lists.sip-router.org
> [mailto:sr-users-bounces@lists.sip-router.org] En nombre de
> Daniel-Constantin Mierla
> Enviado el: martes, 19 de marzo de 2013 10:00 a.m.
> Para: Kamailio (SER) - Users Mailing List
> Asunto: Re: [SR-Users] NAT & Firewall Issues
>
> Hello,
>
> rtpproxy could bring some delays, as another hop in rtp path. But usually is
> not noticeable, unless rtpproxy is on a slow network.
>
> Look at the traffic coming to rtpproxy and going out (with wireshark or
> similar tool) to be sure you have delays from rtpproxy.
>
> Cheers,
> Daniel
>
> On 3/19/13 8:49 AM, Amr Elsharqawi wrote:
> > Hello,
> >
> > I am facing NAT & Firewall problems how I can solve this issue I've
> > tried RTPProxy but voice quality is bad.
> >
> > any tutorial, please
> >
> > Amr
> >
> >
> > _______________________________________________
> > SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing
> > list sr-users@lists.sip-router.org
> > http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
>
> --
> Daniel-Constantin Mierla - http://www.asipto.com
> http://twitter.com/#!/miconda - http://www.linkedin.com/in/miconda
> Kamailio World Conference, April 16-17, 2013, Berlin
> - http://conference.kamailio.com -
>
>
>
> _______________________________________________
> SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
> sr-users@lists.sip-router.org
> http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users

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