ConfiguringMEP Interfaces to Support Ethernet Frame Delay Measurements
Ethernetframe delay measurement is a useful tool forproviding performance statistics
orsupporting or challenging ServiceLevel Agreements (SLAs). By default,Ethernet frame
delaymeasurement uses software fortimestamping and delay calculations. Youcan
optionallyuse hardware timing to assist in this processand increase the accuracy of the
delaymeasurement results. Thisassistance is available on the reception path.
Beforeyou can perform Ethernet frame delaymeasurements on MX Series routers, you
musthave done the following:
•ConfiguredEthernet OAM and CFM correctly
•Preparedthe measurement between twocompatibly configured MX Series routers
•Enabledthe distributed periodic packet management deamon (ppmd)
•Avoidedtrying to perform Ethernetframe delay measurement on aggregatedEthernet
orpseudowire interfaces, which are not supported
•Madesure the MX DPCs support hardware-assisted timestamping if thatfeature is
configured
Atthe end of this configuration, you createtwo MX Series routers that can perform and
displayEthernet frame delay measurementson Ethernet interfaces using optional
hardwaretimestamping. By default, Ethernet frame delaymeasurement uses software
fortimestamping and delay calculations.You can optionally use hardware timing to
assistin this process and increase the accuracyof the delay measurement results. This
assistanceis available on the receptionpath.
Toconfigure hardware-assistedtimestamping:
1. Toenable Ethernet framedelay measurement hardware assistance on the reception
path,include the hardware-assisted-timestamping statementat the [edit protocols
oamethernetconnectivity-fault-managementperformance-monitoring] hierarchy level:
[edit]
protocols{
oam{
ethernet{
connectivity-fault-management{
performance-monitoring{
hardware-assisted-timestamping;# Enable timestampingin hardware.
}
}
}
}
2. Ethernetframe delaymeasurement requires that distributed PPMD is enabled.Before
youcan gather statisticsfor Ethernet frame delay measurement, you must makesure
thatPPMD is configured properly.Without distributed PPMD, delay measurement
resultsare not valid.
Copyright© 2010, Juniper Networks,Inc.122
Junos10.4 MX Series Ethernet ServicesRouters Solutions Guide