Configuring Gigabit Ethernet Two-Color And Tricolor Policers - Juniper JUNOS 10.1 - CONFIGURATION GUIDE 1-2010 Configuration Manual

Configuring Gigabit Ethernet Two-Color and Tricolor Policers

For Gigabit Ethernet and 10-Gigabit Ethernet IQ2 and IQ2-E interfaces on M Series
and T Series routers, you can configure two-color and tricolor marking policers and
apply them to logical interfaces to prevent traffic on the interface from consuming
bandwidth inappropriately.
Networks police traffic by limiting the input or output transmission rate of a class of
traffic on the basis of user-defined criteria. Policing traffic allows you to control the
maximum rate of traffic sent or received on an interface and to partition a network
into multiple priority levels or classes of service.
Policers require you to apply a burst size and bandwidth limit to the traffic flow, and
set a consequence for packets that exceed these limits—usually a higher loss priority,
so that packets exceeding the policer limits are discarded first.
Juniper Networks router architectures support three types of policer:
}
}
}
}
unit 0 {
accept-source-mac {
mac-address 00:01:02:03:04:05 {
policer {
input policer-1;
output policer-1;
}
}
}
}
}
Two-color policer—A two-color policer (or "policer" when used without
qualification) meters the traffic stream and classifies packets into two categories
of packet loss priority (PLP) according to a configured bandwidth and burst-size
limit. You can mark packets that exceed the bandwidth and burst-size limit in
some way, or simply discard them. A policer is most useful for metering traffic
at the port (physical interface) level.
Single-rate tricolor marking (srTCM)—A single-rate tricolor marking policer is
defined in RFC 2697, A Single Rate Three Color Marker, as part of an assured
forwarding (AF) per-hop-behavior (PHB) classification system for a Differentiated
Services (DiffServ) environment. This type of policer meters traffic based on the
configured committed information rate (CIR), committed burst size (CBS), and
excess burst size (EBS). Traffic is marked as belonging to one of three categories
(green, yellow, or red) based on whether the packets arriving are below the CBS
(green), exceed the CBS (yellow) but not the EBS, or exceed the EBS (red).
Single-rate TCM is most useful when a service is structured according to packet
length and not peak arrival rate.
Two-rate Tricolor Marking (trTCM)—This type of policer is defined in RFC 2698,
A Two Rate Three Color Marker, as part of an assured forwarding (AF)
per-hop-behavior (PHB) classification system for a Differentiated Services
Configuring Gigabit Ethernet Two-Color and Tricolor Policers
Chapter 48: Configuring Gigabit Ethernet Accounting and Policing
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