To prevent inter-area routing loops, OSPF does not allow advertising routing information between two non-backbone areas and allows advertising routing information only within an area or between the backbone area and a non-backbone area. Therefore, each ABR must be connected to the backbone area.

Question

Quizplus · Accepted Answer

OSPF requires that all non-backbone areas connect to the backbone area (Area 0) to ensure proper routing and prevent loops, as the backbone area acts as a central hub for inter-area communication.

To Prevent Inter-Area Routing Loops, OSPF Does Not Allow Advertising