Capturing a DSP tap trace on 60Gv2

DSPTAP Trace Capture

To assist in debugging audio issues on the 60Gv2 it is possible to capture a trace of the audio being received on the analogue side of the connection. This can be invaluable in tracking down issues with the audio being processed. To do this will will require a computer with the Wireshark software installed.

1. Start a Wireshark capture on your PC

2. Login to the Vega CLI and start the DSP tap

3. Place a call that shows the issues you are debugging

4. Stop the DSP tap

5. Stop Wireshark and save the file.

The pcap file saved from Wireshark can be submitted along with logs to Sangoma support to help assist troubleshooting.

Contained in the this log file you will find that the Vega Gateway has sent RTP streams starting at port number 50000.

Verify DSPTAP Captured

Below are the list of steps to verify the DSPTAP captured:

• There will be 2 rtp streams for each Vega FXO/FXS port. e.g For 4 port 60Gv2 FXS Vega it will have 8 streams. Port1(50000, 50002), Port2(50004, 50006), Port3(50008, 50010), Port4(50012, 50014).
  If call is being made from FXS port 1, use below wireshark filter to extract the rtp streams (udp && (udp.dstport == 50000 || udp.dstport == 50002)). It will show packets as below:
  
  
  

Open

• Decode these udp packets as rtp

• Analyze the rtp streams

• Export the wav file out of this

Verify Captured DSPTAP file for Fax call

Below are the list of steps to verify the dsptap for fax call

• Capture the DSPTAP using steps 2-5

• Extract the wave file using this step

• Ensure that there are packets being sent from Vega on udp port no based on FXO//FXS port used.
  
  Load the wave file in Audacity, and make sure you can see the

• Open

  

• Attached the dsptap pacp ( ) and wave file( ) extracted out of that. Call was made on  fxs port1