Sencore VB330, Руководство пользователя

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RTP drop limit: If the number of lost RTP packets exceeds the RTP drop limit an alarm will be
raised. Note that error seconds based on packet drops are counted regardless
of this threshold.
Ignore PID loss: A comma separated list of PIDs for which the probe should ignore packet loss.
Packet loss that affects these PIDs will not result in an error-second count, and
the ETR monitoring engine will not count these errors.
6.5 MW (Media Window)
The MW Media Window view provides an at-a-glance status for each of the multicasts/unicasts being
monitored. From the graphs it is easy to see the jitter characteristics of the signal and if there is packet
loss or CC errors present in the signal. Periods of no signal are also displayed.
The measurements are always aggregated over a time interval – typically one second. The IAT(max) is
the maximum time measured between two neighboring IP frames within the measurement time interval
(the peak packet Inter-arrival time). IAT is expressed in milliseconds.
The MLR is the peak estimated number of lost MPEG-2 Transport Stream packets inside any second
within the actual time period. The number of lost TS packets is derived from the continuity counters inside
the TS packet headers.
A common scenario is to have 7 TS packets per UDP frame. Losing an IP packet will therefore usually
(but not always) result in an MLR of 7 (not always the case because some TS packets such as null
packets or PCR packets do not carry a valid CC field).
The patented Sencore VideoBRIDGE Media Window presents both jitter and packet loss measurements
in one graph, with jitter (IAT) values growing upwards (+ve Y) and packet loss (MLR) growing downwards
VB3xx 10G Probe User’s Manual version 5.3 87