Configuring Rtp Statistics Thresholds - Avaya G250 Administration

Table 45: QoS metrics (continued)
Metric
loss
average-loss
remote-loss
average-remote-loss
rtt
local jitter
remote-jitter
SSRC changes

Configuring RTP statistics thresholds

RTP statistics thresholds should be configured so that incrementation of QoS event counters
coincides with real detectable bad QoS in your network. Optimal values are different for each
network. Configure any thresholds that are not already configured as you require them. See
Viewing RTP statistics thresholds
For a description of each metric, see
codec-loss and codec-rtt are useful for evaluating the actual user experience. The other metrics
are useful for identifying network problems that contribute to QoS problems experienced by the
user. For example, the codec-rtt metric indicates the overall delay experienced by the user. If
you configure a meaningful threshold on the codec-rtt metric, metrics such as local-jitter,
remote-jitter, and rtt metrics may help you identify causes when codec-rtt exceeds its threshold.
Description
The estimated network RTP packet loss.
The VoIP engine evaluates the current received
packet loss every RTCP interval — usually 5 to
8 seconds. The VoIP engine postpones loss
estimation until the next interval if the number
of packets received is less than the minimum
statistic window. The minimum statistic window
is configured with the CLI command rtp-stat
min-stat-win.
The average packet loss evaluation since the
beginning of the RTP stream.
The network loss according to the remote RTP
receiver. The device learns of the remote
packet loss from received RTCP messages.
The average remote network loss
measurement since the beginning of the RTP
stream.
The network RTT. This metric does not include
internal delay. The device learns of the RTT
from RTCP messages.
Variation in delay of packet delivery to the local
peer.
Variation in delay of packet delivery to the
remote peer. The device learns of the remote
jitter from RTCP messages.
The number of times the RTP SSRC field in
received RTP packets has changed.
on page 335.
Table 45: QoS metrics
Configuring and analyzing RTP statistics
Evaluation time
Every RTCP
interval.
At the end of the
session.
Each time an RTCP
packet is received.
At the end of the
session.
Each time an RTCP
packet is received.
Every RTCP
interval.
Each time an RTCP
packet is received.
Every RTCP
interval.
on page 336. The codec metrics,
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