430 Chapter A: Answers to the "Do I Know This Already?" Quizzes and Q&A Sections
7
How many queues are available in priority queuing?
There are four queues: high, medium, normal, and low.
8
If a default queue is not specified in the configuration, in which queue are traffic types that
are not defined in the priority list placed?
Unspecified traffic defaults to the normal queue unless configured otherwise. A default
queue should be defined in all queue lists.
9
What happens to traffic in the low-priority queue if there is always traffic in the high-
priority queue?
The Time To Live (TTL) for the traffic might expire and the traffic might be dropped. Also,
the low-priority queue could fill up and overflow, causing dropped traffic.
10
How many queues are available in custom queuing?
There are 17 queues in custom queuing, 016. Only 116 are user-configurable.
11
How is traffic dispatched in a custom queuing implementation?
Traffic is dispatched on a round-robin basis. Each queue is serviced until its service
threshold is reached.
12
How can a higher priority be assigned to a particular queue?
The service thresholds for that particular queue can be expanded to give it a higher
percentage of the overall bandwidth.
13
List the types of compression supported by most Cisco routers.
Link compression, payload compression, TCP header compression, and Microsoft Point-
to-Point Compression are supported by most Cisco router models. Additional types of
compression are supported by other chassis models.
14
When should link compression be implemented?
Link compression works best on point-to-point dedicated circuits that do not require the
use of header information for switching purposes.
15
Which type of compression should be utilized on virtual circuit-based WAN deployments?
Payload compression should be used on VC-based deployments. This leaves the Layer 2
header intact for use by the carrier network.
Answers to the Chapter 10 Q&A Section
1
Where on a router is queuing implemented?
Queuing should be implemented on low-speed WAN interfaces only.