Let me first apologize for what is probably a simple question. I've searched and been unable to find what I'm looking for in previous questions, though I'm sure it's probably trivial. I've had quite a bit of experience using Cisco routers in the past from an ISP standpoint, but I haven't had much experience in dealing with private links and VPN's.
Here's my situation. I've got a client with two locations. They currently have a frame relay connection between the locations and want to keep this as the primary method of communication between the two locations. However they would like to add a DSL connection at each location and use VPN over the DSL connections as a backup to their Frame connection.
One of the locations already has a connection to the internet through DSL, and one would be added at the remote location. The DSL connection at the remote location would only be used for VPN back to the main location and nothing else.
They don't really want the VPN connection up all the time, they would like it to come up as a result of the Frame connection going down. Similar to how you would do a dial-up backup for a frame connection.
Anyway.. This setup is further complicated(or if I'm thinking correctly perhaps actually simplified) by the fact that due to the sensitive nature of the information traversing the frame circuits they are actually running a VPN tunnel over the frame right now.
Any suggestions or thoughts, please be gentle it's my first VPN :)