I am currently reviewing the OSPF configuration of an existing network in an attempt to streamline it.
From a Layer 3 standpoint, this network consists of two core routers in Area 0 (
CORE2) as well as ten other routers (
BB stands for backbone), each an Area Border Router between Area 0 and its own area. These additional areas are standard areas and there are no OSPF routers in them apart for the ABR. (This might have not always been the case, but it sure is now. There are a few more OSPF routers on the network, e.g. a few Anycast DNS servers, but those are all in Area 0.) Each ABR routes some networks directly and also redistributes a few static routes (which OSPF considers external).
Here's an illustration where two out of the ten areas and ABRs are shown as an example:
My question is: does it make sense to keep using areas in this situation? Does using areas simplify shortest-path calculation on the other nine routers if a new directly-routed network is added to or removed from one of the ABRs? What about if a static route is added/removed?