Editing Open Shortest Path First (section)

====Totally stubby area====
[[File:OSPF-Totally stubby area figur.drawio.png|frameless|right]]
A ''totally stubby area'' is similar to a stub area. However, this area does not allow ''summary'' routes in addition to not having ''external'' routes, that is, ''inter-area'' (IA) routes are not summarized into totally stubby areas. The only way for traffic to get routed outside the area is a default route which is the only Type-3 LSA advertised into the area. When there is only one route out of the area, fewer routing decisions have to be made by the route processor, which lowers system resource utilization.

:Occasionally, it is said that a TSA can have only one ABR.<ref>{{cite web|url=http://www.groupstudy.com/bookstore/samples/thomas/|title=Stub Area Design Golden Rules|publisher=Groupstudy.com|access-date=2011-11-30|archive-url=https://web.archive.org/web/20000831182105/http://www.groupstudy.com/bookstore/samples/thomas/|archive-date=August 31, 2000|url-status=dead}}. This is not necessarily true. If there are multiple ABRs, as might be required for high availability, routers interior to the TSA will send non-intra-area traffic to the ABR with the lowest intra-area metric (the ''closest'' ABR) but that requires special configuration.</ref>