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How to force Abacus to respond to DUT when the DUT is not setup to send the initial CNG tones (T.38 fax)?



In general, the Abacus will not proceed through the fax phases, unless it receives the CNG tone from the DUT (whether DUT generated or signal is being passed on from Abacus originating channel).  If this is the case and/or is the expected behavior of the DUT...

1. Please create a new IP(fax) profile so that you can customize the settings (under Call_Sequence/Partition & Timing/Protocols (tab)/Fax Protocol (column)... click on 'NEW' to create a  new profile.  

2. In the T38 tab, enable ‘Full Duplex Socket Mode’, and click 'Ok' to save.

3. Make sure your newly created profile is selected in the Fax Protocol column; click 'Ok' and/or exit back out to the main GUI screen and run your test again. 


** It best to take another pcap or traffic-capture to see what signals are now present after this change.  Other aspects that need consideration if/when you get past this point) are….

 - Possible TCF mis-matches (leading to the failure to train).  If so, in your profile you may need to set the ‘Data Rate Management method’ to ‘Transfer TCF by ICG card’.  Overall, Abacus should be set to perform ‘Transfer TCF...', since UDP is the transport used here.

 - Check that your DUT ‘Error correction scheme…’ match that of the Abacus (IP_fax profile), as to what’s set here.  If not, you will need to change either the Abacus or you DUT settings to match. 

Product : Abacus,Path Confirmation,6.20,SIP,RTP,IP