Yes, you are right! That, and the additional introduced delay, are drawbacks!

Klaus

-----Original Message----- From: Pablo Murillo [mailto:pm@rednet.com.ar] Sent: Friday, December 12, 2003 4:06 PM To: serusers@lists.iptel.org Subject: Re: [Serusers] Totally lost! proxies, firewalls, gateways, etc, etc,etc ...

Thanks Klaus, but ...

If, I use RTP proxy all the traffic would go through my server or am I mistaken?

----- Original Message ----- If you want 2 NATed devices to talk to each other, you MUST use an RTP proxy (except you want to manually configure the NAT router of every participant).

Sessions between one public and one NATed client might work depending on the used SIP applications. Therefore, using an RTP proxy as soon at least one client is behind NAT is suggested!

It's very simple, take a look at the config script at: http://cvs.berlios.de/cgi-bin/viewcvs.cgi/ser/sip_router/etc/n

athelper.cfg?rev=1.1&content-type=text/vnd.viewcvs-markup

This will show you how to test if user agents are behind a NAT, how to rewrite the SIP messages and how to integrate the RTP proxy.

Note: NAT traversal using RTP proxies and the nathelper module works only if the SIP client is symmetric (=sending and receiving on the same port, SIP and RTP). --------------------------------

Pablo Murillo