[Asterisk-Users] Asterisk as SIP client behind NAT

[Patrick]

On Wed, 2006-01-18 at 15:07 +0100, amaury BOSSE wrote:
> I have a problem with SIP on my * box.
> 
> The * server with a private IP address is behind a NAT modem-router
> with a public one.
> 
> I try to connect to a SIP provider which has a * server with public IP
> but it doesn’t works.
> 
> When I try making a call, the provider answers to the SIP INVITE with
> a 404 not found error.
> 
> With a IAX provider, it works find so I am thinking to a NAT problem.
> 
> Do I have to do port forwarding on my router or to add some special
> configuration to Asterisk?

Yes you have to forward SIP udp port 5060 and RTP udp ports
10000-20000 on your modem to the IP of your Asterisk server.
If the port range 10000-20000 is too big for your modem/router
than make it something smaller and make sure you change the range
also in /etc/asterisk/rtp.conf (rtpstart=10000 & rtpend=20000)

Also make sure that you have the following in sip.conf: 
nat=yes
localnet=<your network> (see the examples in sip.conf)

Regards,
Patrick