Chapter 7 663
In addition to bandwidth and delay, IGRP can be configured to track the following
metrics:
Reliability.
Loading.
MTU (static).
15
Name two parameters that can be tuned by IGRP to allow faster convergence.
Turning off or reducing holddown.
Reducing the update timer.
16
As a rule of thumb, how many areas should be connected to a single router?
If a single router is connected to lots of areas, router memory and CPU resources might
be overwhelmed. Limit the number of areas that connect to a single router to three. A
router with high-speed CPU and lots of memory might be able to handle more areas.
17
What is the function of a designated router?
The designated router can send LSAs to the rest of the routers on the multiaccess
subnetwork. The designated router is the router with the highest priority.
18
What is a virtual link?
A virtual link is a logical link between Area 0 and another area that is not physically
connected to the backbone.
19
What is an OSPF area?
Areas are logical groups of OSPF networks that share information about routes. Each
router in the area shares the same database information.
20
True or false: IGRP summarizes on network number boundaries but can be configured to
support variable-length subnet masks.
False.
21
What is split horizon? In what situations might split horizon be useful to the network
design?
Split horizon prevents a router from sending information out the interface from which it
originated. Split horizon might be desirable in networks that use logical subinterfaces on
the same physical interface, such as Frame Relay or ATM.
22
True or false: To ensure fast convergence for large internetworks, EIGRP keeps two routing
tables, the local routing table and the active routing table, of any router three hops away.
False. EIGRP keeps its own local routing table, which is formed from communications
with neighbors, and the active routing table of each adjacent neighbor. This allows a faster
way for EIGRP to determine a route change.
87200333.book Page 663 Wednesday, August 22, 2001 1:41 PM