[asterisk-users] Multi-homed SIP in Asterisk 11?

[Gareth Blades]

On 31/07/13 15:32, Tony Mountifield wrote:
> Most of my experience until recently has been in Asterisk 1.2, and I am
> just starting to make use of Asterisk 11 for new systems.
>
> I have a question about using SIP on a multi-homed machine.
>
> I have a customer who wants an Asterisk box with two network interfaces:
> one on the public Internet (no NAT), and one on a private LAN. The box
> will not do any IP forwarding between interfaces. They want to connect
> to a SIP trunk from an ITSP via the public interface, and to have SIP
> phones on their LAN registered via the private interface.
>
> I haven't tried such a setup before, so before creating a test system,
> I wondered if anyone here has made such a setup, and whether there are
> any issues with getting SDP contents and media routing correct?
>
> Cheers
> Tony
I normally just ensure localnet= and externip= is set correctly. I 
normally also have 'directmedia=no' defined in sip.conf so that asterisk 
is performing store and forward for all the rtp traffic. That does mean 
rtp traffic for internal calls is going via asterisk where it could be 
direct between the phones but the amount of traffic doing this is 
normally pretty trivial so it doesnt matter in most cases.