Queuing and Compression

THE CCNP EXAM TOPICS COVERED IN THIS
CHAPTER INCLUDE THE FOLLOWING:

Determine why queuing is enabled, identify alternative
queuing protocols that Cisco products support, and
determine the best queuing method to implement.

Specify the commands to configure queuing.

Specify the commands and procedures used to verify proper
queuing configuration.

Specify the commands and procedures used to effectively
select and implement compression.

Describe traffic control methods used to manage traffic flow
on WAN links.

Plan traffic shaping to meet required quality of service on
access links.

Troubleshoot traffic control problems on a WAN link.

This chapter teaches you how to use both queuing and compression
to help maintain a healthy network, which is important because
user data consists of many types of data packets roaming the internetwork,
hungering for and consuming bandwidth.
Queuing
is the act of sequencing packets for
servicing—similar to a line at an amusement park with a FastPass or “go to the front” ability.
Compression is the ability to communicate a piece of information with fewer bits, typically by
removing repetitions within the data.
As a network administrator, you can help save precious bandwidth on WAN links, the largest
bottlenecks in today’s networks. With Gigabit Ethernet running the core backbones and 10-gigabit
Ethernet networks just now being deployed, a 1.544Mbps T-1 link is painfully slow. By implementing
both queuing and compression techniques, you can help save bandwidth and get the most for
your money.
In addition, this chapter teaches you the three
queuing
techniques available on the Cisco
router: weighted fair queuing (WFQ), priority queuing, and custom queuing. You will learn
when to use each type, as well as how to configure each type on your router. We also present
an overview of newer queuing and policing technologies, including low latency queuing (LLQ),
class-based weighted fair queuing (CBWFQ), and committed access rate (CAR).
Finally, this chapter provides the information you need to both understand and configure the
types of compression on Cisco routers. The types of compression techniques covered in this
chapter include header, payload, and link compression.