[Asterisk-Users] Listening on one IP and binding to other IP - is this possible ?

[Lukasz Wojciechowski]

Hello

Im new to Asterisk and generally to IPPBX.

Quick specification of my SOHO system:
1. 2 Interfaces: WAN and LAN
4. 5 VoIP phones configured with SIP attached to LAN
5. 1 external SIP line configured as "gateway" for VoIP phones to allow
outbound calls.

What I want is to set secure Asterisk platform. I would like Asterisk to
allow connections only from LAN but I would also like to use 1 SIP
account which requires registration on my provider sip server which
needs Internet connection.

When I set sip.conf "bindaddr" option to my LAN addres I was sure that
Asterisk will use WAN interface for Internet connections but i was wrong
:|.

When I set "bindaddr" back to "0.0.0.0" then all is ok except that
Asterisk allow to connect and register SIP accounts from WAN.

My general question is:
How to make Asterisk listen only on LAN interface and use WAN interface
for Internet connections ?

I could set NAT from LAN => WAN but this would be ugly, so I prefer to
handle this problem using Asterisk configuration.

Thaks in advance for any help