Multi-Stream Analysis
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Current, Maximum, Minimum Average, Standard dev.iation and Range values of
the FTD and the Current, Average and Maximum values of the FDV.
Table 6.10: SLA Delay Statistics
Field Description
FTD (current) Current value of the point-to-point Ethernet Frame Delay
computed as specified in ITU-T Y.1563 and expressed in ms.
To display the current FTD it is required a previous initializa-
tion of a test with Run.
FTD (maximum) Peak value of FTD registered from the beginning of the test.
The FTD (max) value is a packet by packet computed statis-
tic. All relevant SLA packets are considered for calculation of
this statistics.
FTD (minimum) Minimum value of FTD registered from the beginning of the
test.
The FTD (min) value is a packet by packet computed statis-
tic. All relevant SLA packets are considered for calculation of
this statistics.
FTD (average) Average of all registered FTD values from the beginning of
the test.
All relevant SLA packets are considered for calculation of this
statistics (no sampling process is involved in the calculation
of this statistic).
FTD
(standard deviation)
Standard deviation (positive square root of the variance) cor-
responding with all the registered FTD values from the begin-
ning of the test. The standard deviation quantifies the delay
dispersion or delay variation found in the DUT / SUT.
FTD (range) This performance metric is the result of subtracting FTD
(min) from FTD (max). The range is an alternative way to the
standard deviation to quantify the delay dispersion found in
the DUT / SUT.
FDV (current) Current value of the jitter computed as per RFC 3393 and
RFC 1889. Delay variation is computed over consecutively
transmitted packets. The jitter value is smoothed with the
function defined in RFC 1889 before being displayed.
The current FDV constitutes still another metric to quantify
the delay variation in the DUT / SUT.
To display the current jitter it is required a previous initializa-
tion of a test with run.
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