PROBLEM TYPE: "FAX TRANSMISSION"
• The reason of the most Fax transmission problems lie in the "analogue" versus "packetized" transfer of the data.
• Fax bases on analogue modem technology and relies on precise and continuous modulated frequency transmission.
• And just the SIP based packetized transmission technology breaks the required "precise and continuous modulated requency transmission" of the Fax service.
SOLUTION ATTEMPTS FOR "FAX TRANSMISSION" PROBLEMS
With Fax problems you have the following possibilities to solve it:
1. Change the FAX device configuration:
- Reduce transmission rate to 14400 Baud or lower
- Switch off ECM
- Activate any existing VoIP transmission mechanism
- If necessary, replace the FAX machine to test it.
2. Change the codec type in the upstream SIP-Analogue gateway device:
- G.711: for in-band Fax transmission
- T.38: for p