The traditional OSPF recovery is based on calculating {HEAD ~ new shortest paths} from a node to {TAIL ~ all the destinations} in the changed topology 
The traditional OSPF recovery is based on calculating { HEAD ~ new shortest paths } from a node to { TAIL ~ all the destinations } in the changed topology
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH