When are virtual links used in OSPF?
A. When two areas need to communicate and there is no area 0.
B. When an area needs to traverse another area to reach area 0.
C. When two areas are connected to area 0, but there is no direct path between them.
D. When an area needs to connect directly to another area without using area 0.
Answer: B
Which of the following statements regarding area border routers in an OSPF network is true?
A. The term backbone router has the same definition as the term area border router.
B. An OSPF network needs at least one area border router to function.
C. Area border routers connect the backbone area to other areas in an OSPF network.
D. By definition, an area border router must perform route summarization between areas.
Answer: C
