FAX detection over standard phone line?

Hello. I’m analyzing Asterisk for possible use and I have a question about it.

Is Asterisk capable of detecting the nature of an incoming call, FAX or voice, over a standard phone (RJ-11, not VOIP) line? Can that be done without picking up the call? Can it be done at all?

Note that I’m not even sure if this is possible, but it would sure be useful.

I searched for an answer for this question but some doubts do remain. I think that it’s possible with a VOIP call. Is this correct?

Filipe Martins

If the line is an analog pstn line then no , the line has to be answered and then the faxtone is detected,

Fax over voip is VERY unreliable and would normally be done using the T38 protocol so the fact that the call is using T38 means that it would be a fax.

With ISDN if the fax is from an ISDN fax machine then the call would be flagged as fax and as such delivered to another ISDN fax machine


Thanks for the response.

Filipe Martins