as shown in the attached pic,i wish to allow my 2 towns to have internet access when one town is down the other can pass through the other and have internet access,the protocol in use is BGP Protocol that i use to communicate with my Provider.The routers used are cisco 7200 series routers
i want that wentever there is connectivity issues with Town B from CA Telecom,Town B
can pass through Town A and go through to the internet and vice versa.Town A and B communicate using GRE Tunelling