I have a HQ, a DR site, approx 25 branches. All are connected via a BGP MPLS as primary. Our core switch is running OSPF Area 0 in HQ, redistributing into BGP. Branch MPLS Routers are running router on a stick and advertising directly in BGP. At each branch there are two routers, one for MPLS, one for DSL. Right now branches have IPSec VPN (871s) back to main office with static route. I want to change that to DMVPN with OSPF. I also want to have dual hubs, one in HQ, one in DR site. I also plan on migrating the MPLS between the HQ and DR to a VPLS connection. I am not sure on how to configure the OSPF for the branches, how far to extend the Area 0..., etc. Can someone shed some light?