[asterisk-users] Fax detection ...

[Steve Underwood]

Jay R. Ashworth wrote:

>On Sun, Oct 01, 2006 at 02:58:37PM -0700, Lee Howard wrote:
>  
>
>>Well, fax detection isn't entirely reliable anyway.  Even if you assume 
>>that your fax detection feature and operation is flawless in properly 
>>detecting fax tones (and that most likely would be a specious 
>>assumption), not all calling fax machines send fax tones.
>>    
>>
>
>So, y'know, that assertion gets made a lot.
>
>What's the turn rate of fax machines in the market? 3 years?  5?  CNG
>tones are *well* over 10 years old, no?
>  
>
What relevance does that have to CNG? It was a feature of the original 
spec 30 years ago.

>What percentage of fax calls are sent without CNG tones these days?
>  
>
Quite a lot. A large number of FAX machines have CNG turned off. On many 
machines, if select features like sharing a line between FAX and 
answering machine CNG, CED and various other useful behaviour might be 
disabled.

Steve