>I've only got a PAP2T (2 FXS) but from what you describe I'd say that it makes
>sense for the FXO port to be "phone_#_of_pstn" and FXS to be "ext_to_dial."
>I believe FS tries to be endpoint-type agnostic in this scenario. It's a SIP
>call in and gets routed in the dialplan.

This is what I thought as well, where I am unclear is how you register this device
as a gateway then as it isn't like a regular sip provider by means of a gateway
definition? The gateway definition requires a username and password for example
so how do you create the basic definition to allow the spa3102 to push the call into
the public context?