124 Chapter 5: Introduction to the Modular QoS Command-Line Interface
The simplicity of conﬁguration is made possible through the use of a common conﬁgu-
ration structure for all QoS components within the MQC. That is, the basic conﬁguration
steps for conﬁguring all QoS mechanisms is the same, with only small variations in the
conﬁguration that are speciﬁc to the actual mechanism. You can conﬁgure all the mecha-
nisms through a three-step process:
Step 1 Class map conﬁguration
Step 2 Policy map conﬁguration
Step 3 Service policy application
This chapter describes each step in the conﬁguration process, as well as the conﬁguration
options, and also provides examples of MQC commands.
Step 1: The Class Map
The ﬁrst step for conﬁguring any QoS mechanism in the MQC is the conﬁguration of a
class-map. Simply stated, the class map deﬁnes which trafﬁc you want the router to match.
This is the fundamental step that allows the router to differentiate one trafﬁc type from
another. This is trafﬁc classiﬁcation, and without classiﬁcation there can be no QoS.
To differentiate trafﬁc, it is possible to match on one trafﬁc characteristic or multiple
characteristics. If you need to differentiate between trafﬁc from 10.1.1.1 and trafﬁc from
10.1.1.2, for example, the source IP address is the only characteristic that you need to
conﬁgure. If you have multiple trafﬁc streams from 10.1.1.1 and need to differentiate
between those, however, as well as differentiate between multiple streams from 10.1.1.2,
you probably need to classify trafﬁc based on multiple criteria, such as TCP or UDP port.
A possible scenario in which this would come into play might be server 10.1.1.1 that serves
production HTTP and FTP to the Accounting department, and server 10.1.1.2 that serves
nonproduction HTTP and FTP to the IT group that develops applications for the
Accounting department. Understanding that production trafﬁc is the top priority, the devel-
opment group needs their trafﬁc to have a minimum bandwidth guarantee to enable that
group to properly test a new HTTP application before delivering it to the Accounting
department for production use. This means that there will be QoS requirements for all
trafﬁc from 10.1.1.1 and some trafﬁc from 10.1.1.2. As such, just matching by IP address
does not sufﬁce. In this case, there is a requirement to match on multiple characteristics.
Conﬁguring the Class Map
When matching on multiple characteristics, two options exist for creating the class map:
match-any and match-all, as demonstrated in Example 5-1.
Example 5-1 Class Map Options
R1(config)# class-map ?
WORD class-map name
match-all Logical-AND all matching statements under this classmap
match-any Logical-OR all matching statements under this classmap