Iptv Stream Reception Quality Parameters Measurement - Planar IT-100 Operating Manual

The panel of functional keys includes the following keys: F1 is used to open the
settings menu, F2 through F6 are used to set up the current mode. Press the Shift key to
display the functional keys for quick switching between modes.

4.5.2. IPTV Stream Reception Quality Parameters Measurement

In this mode the IPTV stream reception quality parameters are displayed according to
RFC 4445. The screen view and displayed information are shown in figure 4.46.
The following parameters are displayed on the screen:
1) IAT (MIN/AVR/MAX). Minimum/average/maximum value of variability of the arrival
interval of adjacent IP packets throughout the stream measurement. IAT is
measured in ms and can be used to evaluate the stream flatness (jitter);
2) DF (MIN/AVR/MAX). Minimum/average/maximum value of data delay factor
throughout the stream measurement. DF is measured within the second interval
and displayed in ms. In fact, DF indicates the amount of time of data delay in the
receive buffer or the amount of time required to drain the buffer. So, DF indicates
minimal necessary depth of stream reception buffer enabling constant stream rate
at the buffer output and eliminating the data loss. The buffer volume can be
estimated as follows:
V = DF * BR * 1000, where
V is buffer depth in bytes,
DF is data delay factor in ms,
BR is MPEG stream rate in Mbit/s.
3) IP PACKETS. Total number of received IP packets throughout the measurement;
4) MLT. Number of lost MPEG packets throughout the measurement. This
measurement is performed only for RTP protocol, and is based on the analysis of
RTP packets sequence number. The RTP packet is considered to be lost if it is
missing in the buffer for RTP packet sequencing. The buffer allows for up to 10
packets sequencing;
5) IP BITRATE. The rate of IPTV ETHERNET frames in Mbit/s;
6) UPTIME. The IPTV stream measurement time after synchronization. The
synchronization progress bar is indicated until the synchronization is achieved.
The bar graph shown on the screen indicates the distribution of received IP packets
in IAT intervals. Each bar corresponds to a certain IAT interval of 0.4 ms. The bar height
indicates the number of packets corresponding to this IAT interval expressed as percent of
the total number of received packets. The maximum value bar is highlighted and its
interval limit values are indicated at the X axis. The bar graph view allows to analyze the
near-field stream distortion. The near-field stream distortion may be due to high degree of
Figure 4.46
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