NetTool
Users Manual
7-4
Viewing Call Quality Measurements
The VoIP Monitor tracks call quality (RTP data). To
display the VoIP Monitor, do the following:
1. From the Main menu, select VoIP/Toolkit.
2. On the VoIP/Toolkit menu, select VoIP Monitor to
display the screen shown in Figure 7-4:
ahn309s.bmp
Figure 7-4. VoIP Monitor
The VoIP Monitor includes RTP statistics and RTCP
information (when present) for both the phone side and
the network side. You can view this data this while a call is
in progress. Table 7-1 defines the RTP and RTCP
statistics seen on this screen.
Table 7-1. VoIP Monitor RTP/RTCP Statistics
Statistic Meaning
RTP frm The number of RTP frames.
RTP drop The number of dropped RTP frames. An
RTP frame is considered dropped when it
does not arrive within 16 frames.
RTP jttr The difference between the maximum and
minimum frame inter-arrival time. This is
an unbuffered measurement of the raw
packet arrival times.
RTP seqEr The number of frames that arrived out of
sequence but within the 16-frame-drop
window.
RTCP
1
frm The number of RTP frames.
RTCP
1
drop The number of dropped packets as
measured, post buffer, by the endpoint.
RTCP
1
jttr The amount of jitter as reported by the
endpoint.
1
RTCP is an optional control protocol that is sent from the RTP
endpoints. It contains call quality information as reported by the
two RTP endpoints involved in the conversation.