Two-Way Delay Measurement (Eth-Dmm Y.1731) - Nokia 7302 Basics, Management And Oam Manual

Ethernet Connection Fault Management
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8.6 Two-Way Delay Measurement (ETH-DMM
Two-way delay measurement is similar to one way delay measurement except it
measures the round trip delay from the generating MEP. In this case wall clock
synchronization issues will not influence the test results because four timestamps are
used. This allows the remote nodes time to be removed from the calculation and as
a result clock variances are not included in the results.
Delay can be measured using two-way on demand function. The two-way test results
are available single-ended, test initiated, calculation and results viewed on the same
node. There is y1731pm need to be enabled under the MEP on the SAP in order to
enabled this function. An example of an on demand test and results are below. The
latest test result is stored for viewing. Further tests will overwrite the previous results.
Delay Variation is only valid if more than one test has been executed. Delay is
applicable only to down MEPs and as per the recommendation transparent to MIPs.
oam eth-cfm two-way-delay-test d0:0d:1e:00:01:02 mep 101 domain 4 association
1
Two-Way-Delay-Test Response:
Delay 2955 microseconds Variation 111 microseconds
# show eth-cfm mep 101 domain 4 association 1 two-way-delay-test
==================================================================
Eth CFM Two-way Delay Test Result Table
==================================================================
Peer Mac Addr
------------------------------------------------------------------
d0:0d:1e:00:01:02
==================================================================
176
CCM will declare a fault, when:
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The CCM stops hearing from one of the remote MEPs for 3.5 times CC interval
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Hears from a MEP with a LOWER MD level
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Hears from a MEP that is not in our MA
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Hears from a MEP that is in the same MA but not in the configured MEP list
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Hears from a MEP in the same MA with the same MEP id as the receiving MEP
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The CC interval of the remote MEP does not match the local configured CC interval
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The remote MEP is declaring a fault
An alarm is raised if the defect is greater than or equal to the configured
low-priority-defect value.
Y.1731)
3HH-11982-AAAA-TQZZA
"FD 100/320Gbps NT and FX NT IHub System
Basics, Management and OAM Guide"
Delay (us) Delay Variation (us)
2955 111
Issue: 10