Technical information

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Cisco Unified CallManager 4.2(3) Call Detail Record Definition
OL-10659-01
Working with CDRs
numberPacketsLost Integer Designates the total number of RTP data
packets that have been lost since the
beginning of reception. This number
designates the number of packets that were
expected, less the number of packets that
were actually received, where the number
of packets that were received includes any
that are late or duplicates. Thus, packets
that arrive late do not get counted as lost,
and the loss may be negative if duplicates
exist. The number of packets that are
expected designates the extended last
sequence number that was received, as
defined next less the initial sequence
number that was received. The value
remains zero if the connection was set in
“send only” mode.
Default - 0.
jitter Integer Provides an estimate of the statistical
variance of the RTP data packet interarrival
time, measured in milliseconds and
expressed as an unsigned integer. The
interarrival jitter J specifies the mean
deviation (smoothed absolute value) of the
difference D in packet spacing at the
receiver, compared to the sender for a pair
of packets. RFC 1889 contains detailed
computation algorithms. The value
remains zero if the connection was set in
“send only” mode.
Default - 0.
latency Integer Designates value that is an estimate of the
network latency, expressed in milliseconds.
This value represents the average value of
the difference between the NTP timestamp
that the RTP Control Protocol (RTCP)
messages indicates and the NTP timestamp
of the receivers, measured when these
messages are received. Cisco Unified
CallManager obtains the average by
summing all estimates then dividing by the
number of RTCP messages that have been
received.
Default - 0.
Field Name
Range of
Values Description