[asterisk-dev] Proposal for T.38 transparent gateway design in Asterisk

[Kevin P. Fleming]

Lee Howard wrote:
> Kevin P. Fleming wrote:
>> Klaus Darilion wrote:
>>
>>   
>>> Further, FAXOPT should be allow configure the faxdetection flexible, 
>>> e.g. CNG and/or CED tone, incoming or outgoing)
>>>     
>> CED tone is not a reliable discriminator for FAX. CNG tone is, for
>> detection of calling FAX machines, and is already supported by
>> chan_dahdi (and could easily be supported by the other TDM channel
>> drivers as well).
> 
> CNG isn't reliable, either.  A faxmodem dialing with ATDT<number>@ will 
> not produce CNG, and many fax callers will do this in order to not 
> disturb the receiver if they happen to call a human instead of a machine.
> 
> Fax detection is not entirely reliable either way ... neither detecting 
> CED nor detecting CNG.

Yet more non-conformance with ITU-T recommendations :-)

-- 
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
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