The following questions test your understanding of the topics covered in this chapter. The final questions in this section repeat the opening "Do I Know This Already?" questions. These are repeated to enable you to test your progress. After you have answered the questions, find the answers in Appendix A. If you get an answer wrong, review the answer and ensure that you understand the reason for your mistake. If you are confused by the answer, refer to the appropriate text in the chapter to review the concepts.
In a totally stubby area, which routes are not propagated into the area?
Where would you see whether a learned network was within the same area as the router you were looking at?
An Area Border Router must be resident in which area?
What does ABR stand for, and what LSAs will it forward?
State two advantages in creating areas in OSPF.
What is an external route, and on which type of router will this route be introduced?
Which command in OSPF shows the network LSA information?
Why is the use of VLSM important in the design of OSPF?
Given the networks 18.104.22.168 and 22.214.171.124, both with the mask of 255.255.255.0, is it possible to summarize these into one subnet? If so, state the new subnet and mask.
What is a discontiguous network?
A virtual link in OSPF is used to solve what problem?
State one disadvantage for making an NBMA Frame Relay cloud Area 0.
State one advantage in making the centralized routers and network resources dwell in Area 0 while the Frame Relay cloud and the stub remote LANs reside in satellite stub areas.
How does creating a number of areas in OSPF reduce the number of SPF calculations?
How does a stub area differ from the backbone area?
How does a totally stubby area differ from a stub area?
State the different LSA types.
Where does the backbone router reside, and what is its function?
Are there any considerations for OSPF configured with VLSM sending routing updates into RIPv1?
There are two types of summarization. What are they?
Can the following subnets with a mask of 255.255.255.0 be summarized? If so, state the subnet and mask that can be used.
Why can interarea summarization be configured only on ABRs?
What command would be used to create a totally stubby area?
What is a virtual link, and what command would be used to create it?
Where would you issue the command to summarize IP subnets? State the command that would be used.
How would you summarize external routes before injecting them into the OSPF domain?