I am studying OSPF, and It seems to me that totally stub areas just saves the day. Why do we need stub areas?
To be more clear, as I read, I understand that OSPF areas designed as star topology, so there is one backbone area, and the other areas. So other areas connected to backbone area thru an ABR.
When I define that area as stub, how are the type 3 LSAs coming from backbone used, because there is only one connection to backbone area (a complete default route is enough indeed)?. In other words, can you give me a sample topology, that I should define the area as stub, but not totally stub?