Asterisk & Linksys SPA3102

Hello all,

I’m new with Asterisk and i could use some help.
I have an Asterisk (11.8.1) server and some IP Phones behind it.
Calls between the IP Phones are ok.
Call to another sip server (sip trunk from Asterisk) are also ok.

I also have a Linksys 3102 which I want to use to make outgoing calls to PSTN/GSM networks through its FXO port.
So it will be like this,
IP phone – Asterisk --Linksys SPA3102 – PSTN/GSM network

I guess a SIP trunk should be established between Asterisk and SPA3102.
I’m confused with this, who is going to make the registration ?
Asterisk or SPA3102 ?
How I’m supposed to configure these two ?

Regards,
George

Normally the PSTN gateway would register, or you would use static addresses.

Should I configure the PSTN or the Line 1 on the SPA3102 ?