Chapter 32. Designing QoS

Designing a QoS scheme can be a relatively simple task or a very large project. The scale of the solution depends on the complexity of your network and the needs of your business. As a general rule, I like to plan everything I do with an end-state design in mind. Even if I’m implementing a QoS scheme for a company that currently doesn’t have VoIP, I’ll design one that assumes VoIP is coming in the future.

In this chapter, I’ll walk you through designing a QoS scheme for a network that will require VoIP. Designing QoS is a two-part process: first, you must determine the requirements for the system, and then you have to configure the routers. We’ll use low-latency queuing (LLQ), which is the recommended solution according to Cisco. I will also outline two traffic-shaping scenarios and show the steps necessary to implement them.