User Guide

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Chapter 9. Telephony
9.1. Introduction
Wireshark provides a wide range of telephony related network statistics which can be accessed via the
Telephony menu.
These statistics range from specific signaling protocols, to analysis of signaling and media flows. If
encoded in a compatible encoding the media flow can even be played.
9.2. RTP Analysis
The RTP analysis function takes the selected RTP stream (and the reverse stream, if possible) and generates
a list of statistics on it.
Figure 9.1. The "RTP Stream Analysis" window
Starting with basic data as packet number and sequence number, further statistics are created based on
arrival time, delay, jitter, packet size, etc.
Besides the per packet statistics, the lower pane shows the overall statistics, with minimums and maximums
for delta, jitter and clock skew. Also an indication of lost packets is included.
The RTP Stream Analysis window further provides the option to save the RTP payload (as raw data or, if in
a PCM encoding, in an Audio file). Other options a to export and plot various statistics on the RTP streams.
9.3. VoIP Calls
The VoIP Calls window shows a list of all detected VoIP calls in the captured traffic. It finds calls by
their signaling.