Question : VOIP gateway

I need to spec out a voip gateway, any help would be appreciated

1) Expected approx 20 concurrent connections
2) I want to use a Cisco router
3) what type of network module do I need?
4) Are the seperate calls broken out on the card or do I need something else?

I am unclear of the interface between an IP based system and the PSTN, any info would help

harbor235 ;}

Answer : VOIP gateway

yes
you need to have pvdm voice modules. ebay number 220499069860

http://cgi.ebay.co.uk/Cisco-NM-HDV-1T1-24E-w-VWIC-1MFT-T1-4-PVDM-12-Modul_W0QQitemZ220499069860QQcmdZViewItemQQptZCOMP_EN_Networking_Components?hash=item3356c4cba4
 The picture shows the pvdm modules on the left the T! on the right.
This is how to configure the voice wic.
http://www.cisco.com/en/US/docs/interfaces_modules/port_adapters/install_upgrade/voice/t1.e1_digital_voice_install_config/3592conf.html

Greg