Cam Hardware Classifiers Overview - Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - POLICY MANAGEMENT CONFIGURATION GUIDE 2010-10-04 Configuration Manual

JunosE 11.3.x Policy Management Configuration Guide

CAM Hardware Classifiers Overview

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when all policies have 16 hardware classifier entries or fewer, and supports 8127 policies
when all policies have 17 to 32 hardware classifier entries.
You can configure a combination of the two versions of FPGA hardware classifier-based
policies—you can have some that contain 16 or fewer classifier entries and others with
more than 16 entries. In this case, between 8127 and 16,255 policies are supported,
depending on the actual configuration.
You can also configure hardware classifier-based policies that have more than 32 classifier
entries. The router groups the classifiers into blocks of 32. For example, if you configure
a policy with 100 classifier entries, the router groups these as 3 policies that have 32
classifier entries and 1 policy with 4 classifier entries. The group with 4 classifier entries
actually consumes 16 classifier resources, which is the minimum number consumed for
a group in a mixed-mode hardware classifier configuration.
Unlike policies that are based on software classifiers, policies that are based on FPGA
hardware classifiers consume resources at a rate of one resource per policy, regardless
of the number of different hardware classifier categories in the policy. For example, if a
classifier list has three hardware classifiers, such as destination address, source address,
and protocol, the policy referencing that classifier list consumes only a single hardware
classifier resource.
The same is true when multiple policy rules reference the classifier list. For example, if
four policy rules reference the same classifier list (which contains three hardware
classifiers), then still only one classifier entry is consumed.
Content-addressable memory (CAM) hardware classifiers are supported on the
OC48/STM16, GE-2, ES2 4G, ES2 10G, ES2 10G Uplink, and GE-HDE line modules. Table
17 on page 152 lists CAM hardware classifiers and the software classifiers supported for
each interface type.
The OC48/STM16 line module supports 128,000 144-bit CAM entries, and the GE-2 and
GE-HDE line modules support 64,000 144-bit CAM entries. The ES2 4G LMs on E120 and
E320 routers support 256,000 144-bit CAM entries, and the ES2 10G and ES2 10G Uplink
LMs on E120 and E320 routers support 128,000 144-bit CAM entries. For most
configurations, each classifier entry in a policy consumes one CAM entry. However, a
policy that has only the default classifier consumes no CAM resources.
In this example, the policy consumes a total of four CAM entries: two entries for clacl1,
one for clacl2, and one for the default classifier.
host1(config)#ip classifier-list clacl1 ip host 192.168.1.1 host 192.168.2.2 tos 1
host1(config)#ip classifier-list clacl1 ip host 192.168.1.1 host 192.168.2.2 tos 2
host1(config)#ip classifier-list clacl2 tcp any any tcp-flags "SYN"
host1(config)#ip policy-list policy1
host1(config-policy-list)#classifier-group clacl1
host1(config-policy-list-classifier-group)#forward
host1(config-policy-list-classifier-group)#exit
host1(config-policy-list)#classifier-group clacl2
host1(config-policy-list-classifier-group)#forward
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