Juniper EX9200 Series, Features Manual

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To rate-limit Layer 3 traffic, you can apply a two-color policer in the following ways:
•
Directly to a logical interface, at a specific protocol level.
•
As the action of a standard stateless firewall filter that is applied to a logical interface,
at a specific protocol level.
To rate-limit Layer 2 traffic, you can apply a two-color policer as a logical interface policer
only. You cannot apply a two-color policer to Layer 2 traffic through a firewall filter.
Related
Documentation
Two-Color Policer Configuration Overview on page 49
•
•
Example: Limiting Inbound Traffic at Your Network Border by Configuring an Ingress
Single-Rate Two-Color Policer on page 56
•
Example: Configuring Interface and Firewall Filter Policers at the Same Interface on
page 64
Example: Limiting Inbound Traffic at Your Network Border by Configuring an Ingress
Single-Rate Two-Color Policer
This example shows you how to configure an ingress single-rate two-color policer to
filter incoming traffic. The policer enforces the class-of-service (CoS) strategy for
in-contract and out-of-contract traffic. You can apply a single-rate two-color policer to
incoming packets, outgoing packets, or both. This example applies the policer as an input
(ingress) policer. The goal of this topic is to provide you with an introduction to policing
by using a example that shows traffic policing in action.
Policers use a concept known as a token bucket to allocate system resources based on
the parameters defined for the policer. A thorough explanation of the token bucket
concept and its underlying algorithms is beyond the scope of this document. For more
information about traffic policing, and CoS in general, refer to
QOS-Enabled
Networks—Tools and Foundations by Miguel Barreiros and Peter Lundqvist. This book is
available at many online booksellers and at www.juniper.net/books.
• Requirements on page 56
• Overview on page 57
•
Configuration on page 59
•
Verification on page 63
Requirements
To verify this procedure, this example uses a traffic generator. The traffic generator can
be hardware-based or it can be software running on a server or host machine.
The functionality in this procedure is widely supported on devices that run Junos OS. The
example shown here was tested and verified on MX Series routers running Junos OS
Release 10.4.
Copyright © 2016, Juniper Networks, Inc. 56
Traffic Policers Feature Guide for EX9200 Switches