IEEE 1588 Analysis
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Sync PTD (range) Difference between the Sync PTD (maximum) and Sync
PTD (minimum).
This is an Sync PTD statistic but like it happens with the
Sync PTD (std. dev.) it is more related with delay variation
than with absolute delay. It could be that the Sync PTD
(range) is known even if Sync PTD (maximum) and Sync
PTD (minimum) are not. For this reason, the Sync PTD
(range) statistic is computed in slave emulation, pseudo-
slave emulation (Test mode) and passive monitoring modes.
Sync PDV (current) Current value of t the Packet Delay Variation (PDV) com-
puted as per RFC 3393 and RFC 1889. Delay variation is
computed over consecutively transmitted packets. The
instantaneous value is smoothed with the function defined in
RFC 1889 before being displayed.
The Sync PDV (current) is computed in slave emulation,
pseudo-slave emulation (Test mod e) and passive monitoring
modes.
Sync PDV
(maximum)
Maximum value of Sync PDV (current) registered from the
beginning of the test.
The Sync PDV (maximum) is computed in slave emulation,
pseudo-slave emulation (Test mod e) and passive monitoring
modes.
Sync PDV
(average)
Mean value of all the Sync PDV values computed from the
beginning of the test.
Each individual delay variation is evaluated as the absolute
value of the PTD associated to a given frame minus the PTD
associated to the frame transmitted next. All possible con-
secutive frame transmission events are taken into account
for the calculation of this performance metric. The only
exception to this rule is if one or both frames are lost.
The Sync PDV (average) is computed in slave emulation,
pseudo-slave emulation (Test mod e) and passive monitoring
modes.
Delay req. PTD
(current)
Last calculated value of the PTD experienced by IEEE 1588
Delay req. messages (or Peer delay req. messages) when
they travel from the test unit to the master (with end-to-end
delay mechanism) or from the test unit to the peer entity
(with peer-to-peer delay mechanism).
Table 9.7: IEEE 1588 Delay Statistics
Result Description
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