Debugging voice data
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SmartWare Software Configuration Guide
42 • VoIP debugging
Depending on the type of problem, some debug monitors are more useful than others. Try to avoid enabling all
monitors at the same time, as this generates a lot of output and can degrade system performance. The follow-
ing examples show some typical debug cases and what monitors should be switched on in these cases.
Example:
Debugging voice connections
Symptoms:
Voice quality is bad (dropouts), the voice connection is only established in one direction or not at
all, there is only noise instead of voice, no tones are played (e.g. dialtone).
Prerequisite:
The call is established from a signaling point of view (see chapters Debug H.323 Data and Debug
Session Control Data).
Use the following debug monitors to start with:
Depending on the type of problem, continue using one or more of the following monitors:
Example:
Debugging Fax connections
Symptoms:
Fax transmission starts but is interrupted and the Fax machines terminate with an error message,
Fax transmission does not start at all, the unit’s firmware does not detect Fax.
Prerequisite:
Fax transmission is configured for T.38 relay in the voip profile. The call is established from a sig-
naling point of view (see section
“Debugging voice data”
on page 549).
Attention:
Special signaling procedures are used for the transition between voice and fax data transmission. It
may be that the initial call setup is correct, but that the signaling to T.38 over H.323 is faulty. The session-con-
trol and H.323 signaling monitors (see Debug Session Control Data, and Debug H.323 Data) might also be
helpful to identify these cases.
debug dsp t30
Traces the flow of T.30 communication states between the fax machines
(for T.38 Fax transmission only), and logs changes. Gives approx.
10lines of debug output per transmitted fax page.
Usage: To debug all T.38 Fax related problems.
debug dsp ifp
Decodes the IFP (Internet Fax Protocol) elements within T.38 packets.
More detailed decoding than T.30 monitor, but can generate a lot of
output.
usage: To debug Fax related problems.
Step
Command
Purpose
1
unit#debug voip events
Enable the voip events monitor.
2
unit#debug dsp error
Enable the DSP error monitor.
3
unit#debug voip rtp
Enable the RTP debug monitor
Command
Purpose
unit#debug dsp events
Enable the DSP events monitor.
unit#debug voip dejitter
Enable the dejitter buffer monitor.
unit#debug voip rtp
Enable the RTP debug monitor
unit#debug voip cs
Enable the CS debug monitor
