Quick Reference Guide

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Deploying DiffServ
The four basic steps necessary to deploy DiffServ are:
1. Create class-maps. (See Creating Class-maps/DiffServ Classes on page 180.)
A class-map is used to differentiate between types of traffic based on a packet’s match to defined rules in the
class-map. For information on using a class-map in configuration scripting, see Using Configuration Scripts on
page 31.
2. Create a policy-map. (See Creating a Policy-Map on page 182.)
A policy-map references a class-map and defines the actions to be taken for traffic in a referenced class.
3. Apply the policy to interfaces. (See Applying Policies on page 183.)
Apply the policy to the interfaces in an ingress or egress capacity.
4. Enable DiffServ globally. (See Enabling Differentiated Services on page 184.)
The following command sequence is annotated to show the four stages described above. The example
configures a policy of 1MByte rate limiting, with a 128K burst, sets a CoS, and assigns it to a port:
Figure 12-136. DiffServ Example: Configuring Rate Limiting on a Port
Using “class-map” policy options, you can configure more granular matching based on Layer 2 or Layer 3
headers. Input rate limiting is configured with the
police-simple command. Use traffic-shape for egress rate
shaping.
Creating Class-maps/DiffServ Classes
The first step in deploying DiffServ is to create a DiffServ class. From the Global Config mode, use the
class-map match-all classname command.
The
match-all class type indicates that all of the individual match conditions must be true for a packet to be
considered a member of the class.
class-map match-all match_all
match any
exit
!Completed Step 1!
policy-map rate_limit in
class match_all
police-simple 1024 128 conform-action set-cos-transmit 7 violate-action drop
exit
!Completed Step 2!
interface 1/0/7
service-policy in rate_limit
no shutdown
exit
!Completed Step 3!
diffserv
!Completed Step 4!