Gateway to Asterisk via PRI

I have an question about Samsung DCS-VIP Internet Keyphone.

Now days I have to solution DCS Vip ( company 1) and an IP-solution ( Asterisk ) at company 2 located att same address. But now is DCS vip to small
for my company and I will switch to same IP solution as my company 2 but I need to have my BRI connection as backup for security.

So my qeustion is if it´s possible to use DCS Vip as a bridge from my IP solution to BRI.

Like This

Asterisk IP solution — phone call via IP

Backup if IP fail — call through DCS VIP as a Gateway to BRI

A simple picture of my wanted solution can you find att jndcom.com/DCS_as_gateway-fi … de0001.htm

I Hope you understand my question.

Change the text from Pri to Bri. Even another question about an another solution. I can even use a ordinary telephone line if it´s possible to use a ordinary modem

If not my Samsung DCS Vip not can be use I can think me use a ordinary telephone line and modem or mobilephone ( ericsson Z1010 ) connected to Aterisk server.

It´s for security porpose. If I need to call emergency call so must I config PBX to call with this line otherwise the emergency call will call wrong area for police etc. My ISP sends all my IP calls from Stockholm and I live in a small town 40 km away. I need to let my emergency call a near emergency operator.

Please help me with a solution. ( Cheapest as possibly)