ISDN backup for VPN

[lgardino]

I'm tasked with using ISDN as a backup for VPN's. Is there a way to do this securely?

[paqiu]

Yes, you can. You can apply the crypto map to the bri interface and dialter interface.

You can encrypt the data over ISDN link in the same time as your normal VPN link (Serial interface or ethernet interface).

Here is the CCO sample config for that:

http://www.cisco.com/warp/customer/707/ipsec_dialerwatch.html