Juniper JUNOS 10.1 - CONFIGURATION GUIDE 1-2010 Configuration Manual page 819

ETH-DM Statistics
Ethernet frame delay statistics are the frame delay and frame delay variation values
determined by the exchange of frames containing ETH-DM protocol data units (PDUs).
A CFM database stores CFM-related statistics and—for Ethernet interfaces that support
ETH-DM—the 100 most recently collected ETH-DM statistics for that pair of MEPs.
You can view ETH-DM statistics by using the
of the
statistics for the MEP that collects the ETH-DM statistics you want to view.
Table 73 on page 749 describes the ETH-DM statistics calculated in an ETH-DM session.
Table 73: ETH-DM Statistics
Field Name
†
One-way delay (μsec)
Two-way delay (μsec)
Average delay †
For a one-way ETH-DM session, statistics are collected in an ETH-DM database
at the router that contains the receiver MEP. For a detailed description of one-way
Ethernet frame delay measurement, including the exchange of one-way delay
PDU frames, see "Ethernet Frame Delay Measurements Overview" on page 739.
For a two-way ETH-DM session, statistics are collected in an ETH-DM database
at the router that contains the initiator MEP. For a detailed description of two-way
Ethernet frame delay measurement, including the exchange of two-way delay
PDU frames, see "Ethernet Frame Delay Measurements Overview" on page 739.
show oam ethernet connectivity-fault-management
Field Description
For a one-way ETH-DM session, the frame delay, in microseconds, collected at the receiver MEP.
To display frame delay statistics for a given one-way ETH-DM session, use the
form of the
mep-statistics show oam ethernet connectivity-fault-management
receiver MEP for that session.
For a two-way ETH-DM session, the frame delay, in microseconds, collected at the initiator MEP.
When you start a two-way frame delay measurement, the CLI output displays each DMR frame
receipt timestamp and corresponding DMM frame delay and delay variation collected as the
session progresses.
To display frame delay statistics for a given two-way ETH-DM session, use the
form of the
mep-statistics show oam ethernet connectivity-fault-management
initiator MEP for that session.
When you start a two-way frame delay measurement, the CLI output includes a runtime display
of the average two-way frame delay among the statistics collected for the ETH-DM session only.
When you display ETH-DM statistics using a
average one-way and two- frame delays among all ETH-DM statistics collected at the CFM session
level.
For example, suppose you start two one-way ETH-DM sessions for 50 counts each, one after the
other. If, after both measurement sessions complete, you use a
ETH-DM statistics for that CFM session, the
among all 100 statistics.
Guidelines for Managing ETH-DM Statistics and ETH-DM Frame Counts
Chapter 44: Configuring ITU-T Y.1731 Ethernet Service OAM
delay-statistics
command to display the CFM
command, the
show Average delay
show
Average delay field displays the average frame delay
or form
mep-statistics
or
delay-statistics
command at the
or
delay-statistics
command at the
field displays the
command to display 100
749