6.7 Stub, Totally Stubby, and Not-So-Stubby Areas  
  6.7.2 Stub and totally stubby area criteria  
An area can be qualified as a stub or totally stubby when it meets the following criteria:
  • There is a single exit point from that area.
  • The area is not needed as a transit area for virtual links. Virtual links are discussed at the end of this module.
  • No ASBR is internal to the stub area.
  • The area is not the backbone area, or Area 0.

These criteria are important because a stub or totally stubby area is configured primarily to exclude external routes. If these criteria are not met, external links may be injected into the area, invalidating their stubby nature.

 

Interactive Media Activity

Drag and Drop: ID the Area

Upon completion of this activity, the student will be able to identify the difference between stub and totally stubby areas in OSPF.