Figure 13: Multifield Classifier Based On Tcp Source Ports - Juniper EX9200 Features Manual

Traffic Policers Feature Guide for EX9200 Switches
Requirements
Overview
128
classifier is insufficient to classify a packet, when peering routers do not have CoS bits
marked, or the peering router's marking is untrusted.
Requirements on page 128
Overview on page 128
Configuration on page 129
Verification on page 132
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.
A classifier is a software operation that inspects a packet as it enters the router or switch.
The packet header contents are examined, and this examination determines how the
packet is treated when the network becomes too busy to handle all of the packets and
you want your devices to drop packets intelligently, instead of dropping packets
indiscriminately. One common way to detect packets of interest is by source port number.
The TCP port numbers 80 and 12345 are used in this example, but many other matching
criteria for packet detection are available to multifield classifiers, using firewall filter
match conditions. The configuration in this example specifies that TCP packets with
source port 80 are classified into the BE-data forwarding class and queue number 0.
TCP packets with source port 12345 are classified into the Premium-data forwarding
class and queue number 1.
Multifield classifiers are typically used at the network edge as packets enter an
autonomous system (AS).
In this example, you configure the firewall filter mf-classifier and specify some custom
forwarding classes on Device R1. In specifying the custom forwarding classes, you also
associate each class with a queue.
The classifier operation is shown in

Figure 13: Multifield Classifier Based on TCP Source Ports

Figure 13 on page 128.
Copyright © 2016, Juniper Networks, Inc.