CHAPTER11
ITU-T Y.1731 Ethernet Frame DelayMeasurements•EthernetFrame Delay Measurements on page119
•ConfiguringMEPInterfaces to Support Ethernet Frame DelayMeasurements on page 122
•Triggeringan Ethernet Frame DelayMeasurements Session on page 123
•ViewingEthernet Frame Delay Measurements Statisticson page 124
•Example:Configuring One-Way EthernetFrame Delay Measurements with
Single-TaggedInterfaceson page 125
•Example:Configuring Two-WayEthernet Frame Delay Measurementswith
Single-TaggedInterfaceson page 130
•Example:Configuring Ethernet Frame Delay Measurementswith Untagged
Interfaceson page 134
EthernetFrame Delay Measurements
Performancemanagementdepends on the accuratemeasurement of service agreement
objectiveparameters, which can include bandwidth and reliability.In many cases, a
serviceprovider could be subject topenalties imposed by regulation, statute,or contract
ifnetwork performance is not within the bounds established for the service. One key
performanceobjective is delay,along with its close relative, delay variation(often called
jitter).Some applications will function just as well with high delaysacross the network
andhigh delay variations (such as bulk file transfer),while other applications (such as
voice)can only function with low and stabledelays. Many networks invoke protocolsor
featuresavailableat Layer 3 (the packet layer) or higher to measurenetwork delays and
jitterlink-by-link. However,when the network consists of many Ethernet links, there is
littleavailable at Layer2 (the frame layer) that allows routersto measure frame delay
andjitter.This is where the ability to configure and monitorEthernet frame delay is helpful.
Ona Juniper Networks MX SeriesEthernet Services Router equipped with the Distributed
PortConcentrator(MX-DPC) only, youcan perform Ethernet frame delay measurements
(referredto as ETH-DM in Ethernet specifications).This feature allows you to configure
on-demandOperation, Administration, and Maintenance (OAM)statements for the
measurementofframe delay and frame delay variation(jitter). You canconfigure Ethernet
framedelay measurement in either one-way or two-way(round-trip) mode to gather
framedelaystatistics and simultaneous statisticsfrom multiple sessions. Ethernet frame
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