Does anyone know of a tutorial or guide that shows how to route/forward incoming calls (FXO/PSTN) to a soft-phone/laptop that is outside the LAN where asterisk resides? Worse, the laptop can only be resolved using its dyndns name and may/may not be behind a NAT router. Assuming I can punch enough holes in the various fire-walls, does this have a hope of working with a simple configuration? I suspect that the NAT router won’t know where to send the incoming sip data and all will be lost. Are there any other options here?
It should be relatively straightforward. You will need to make sure that your Asterisk server is reachable from outside your LAN by opening suitable holes in the firewall for the SIP signaling and RTP Streams. The easiest way to do this to go to the port forwarding section of your router and forward the appropriate ports (5060 for SIP and 10000-20000 for RTP)
Then you will need to configure your softphone client on the laptop to register with Asterisk. This will let Asterisk know where your laptop is and how to reach it. Dynamic DNS is not required. You will need to configure Asterisk to tell it that your laptop is using a dyanmic address since the laptop will move from time to time and you should set it up for NAT=yes and reinvite=no in your SIP.conf file.
Just to second the reply above, it really should be that straight forward. Your laptop needs to be able to find & connect to the Asterisk server, the Asterisk server doesn’t need to be able to find your laptop.
I’ve done this exact thing, and it was very easy.