VeEX RXT3900, User Manual

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the mean deviation of the difference in packet spacing at the receiver compared to the sender for a pair of packets.
If Si is the timestamp from packet i, and Ri is the time of arrival for packet i, then for two packets i and j, D(i,j) = (Rj - Ri) - (Sj -
Si).
The interarrival jitter is calculated continuously as each data packet i is received from source according to the formula J(i) = J(i-
1) + (|D(i-1,i)| - J(i-1))/16.
MAPDV Jitter:
The true average mean-absolute packet delay variation in milliseconds. Per ITU-T G.1020.
If the nominal arrival time (denoted below ai) for a packet is known or can be determined, then the absolute delay variation is
abs(ti - ai).
The mean absolute packet delay variation is therefore MAPDV = mean( abs(ti - ai) ).
Packet Statistics (Page 3) - Sample from VoIP Expert - Client/Server Mode
Average PDV:
The running average mean-absolute packet delay variation in milliseconds. This average takes the difference of
the average positive and average negative envelopes. Per ITU-T G.1020.
Mean delay Di = (13.Di-1 + ti-1) / 16 positive deviation Pi = ti - Di if ti > Di negative deviation Ni = Di - ti if ti < Di MAPDV2 =
mean( Pi) + mean(Ni ).
Max Avg MAPDV:
The maximum of the average mean-absolute packet delay variation in milliseconds.
Maximum PPDV
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Events
Events
tab displays a time stamped log of the various test steps with Pass/Fail criteria.
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VX1000 VoIP Expert Results
VX1000 displays the list of available test results.
It automatically stores the results for all the client connections.
VX1000 Results Tab
RXT-3900 e-Manual D07-00-111P Rev A00