ABRs of a Stub area do not flood Type-5 and Type-4 LSAs to the Stub area. Therefore, the Stub area does not have the external AS routing capability. ABRs of the Stub area advertise a default route to the stub area to guide packet forwarding to the external of the AS.

Question

Quizplus · Accepted Answer

In OSPF, a stub area is designed to block external routes (Type-5 LSAs) and summary ASBR routes (Type-4 LSAs) to reduce routing table size. Instead, a default route is advertised by the ABR to handle traffic destined outside the AS.

ABRs of a Stub Area Do Not Flood Type-5 and Type-4