A CNG signal is the fax machine sound you may hear when there is a fax machine connected to the other end of the line. Kerio Operator can detect the signal and start receiving faxes automatically.
- In the Administration interface, Navigate to Configuration > Extensions.
- Double-click a selected extension.
- On the Advanced tab, select one of the following fax detection methods:
- Dial extension, wait for answer, detect CNG: PBX dials an extension, waits for an answer and then starts detecting the CNG signal. User has to answer a call first in order to receive faxes. When a fax tone is detected, the call will be taken over by Kerio Operator.
- Answer, detect CNG, dial extension: PBX answers a call first, then detects the CNG signal and immediately dials an extension. If the user does not answer the phone, a fax mail is received and users have a missed call on their phone display. This option is suitable for occasional fax transmissions.
- Answer, detect CNG, wait 3.5 seconds, dial extension: Extension is dialed after a 3.5-second delay which is used to detect faxes. There will not be any missed calls shown on the phone's display. Regular calls will be automatically answered and will be followed by a 3.5-second delay of silence. This option is suitable for more frequent fax usage.
- Answer, detect CNG, wait 3.5 seconds (ringing tone), dial extension: The PBX will generate a ringing tone instead of waiting in silence. This option is also suitable for more frequent fax usage and may be less confusing to human callers.
- Save the settings.
The selected fax detection method will apply on the next fax connection attempt onwards.