Asterisk as a PSTN gateway through Cisco 1760

Evening all,

Actually I’m trying to configure asterisk as a PSTN gateway (using SIP). I haven’t got any card in the asterisk server but i want to tranfer the calls throught a cisco access routeur (1760) connected to PSTN.

Here is the configuration:
Asterisk <------> Cisco 1760 <------> PSTN

So basically i want to route any incoming SIP calls straight on to the PSTN through the access router.

Can anyone have some example configuration files for this simple scenario of a pstn gateway?

Cheers in advance,