This is Jay Kishan. I work in Pakistan Petroleum Limited as a Network Associate. There is a little problem that i am facing recently. We have a Head Office in Karachi and a Remote Location is Islamabad. We are connecting them with a Primary DXX Link with an active VSAT Backup Link. As soon as the DXX Link goes down the VSAT Link comes up automatically. But the DXX Provider has introduced a few more non-cisco devices in the middle and now we have to create a tunnel from our ISB 2610 Router to KHI 3661 Router. The reason for creating the tunnel is that we dont want the DXX provider to know our network. But the problem that we have at our hand is that the tunnel never goes down as the interfaces on both the routers are connected to devices that wont go down. But there can be a problem in some other middle device because of which the link may not work. So the situation is that even the DXX Link isnt working the tunnel is still up and the VSAT Backup link doesnt come up. So how can i make sure that if the DXX Link stops working the tunnel could sense it and the VSAT Backup link comes up automatically. I will be very much thankful for any sort of help. Thanks in advance.