[Asterisk-Users] fax <-> misdn <-> zap <-> fax // fax <-> misdn <-> ATA <-> fax

[Steve Underwood]

Rico -mc- Gloeckner wrote:

>Hello,
>
>
>I tried the above setups and am having large problems sending and
>receiving faxes, even in very low speeds (9600 and far below).
>
>Faxes are either shifted (i.e. missing lines) or corrupt at all, some
>faxes do break with communication errors (although CRC-alike algorithms
>are turned off) or in alot of cases only the upper quarter or 1/8 is
>transferred.
>
>Iam seeking for any idea on how to optimize the transfer or where to
>seek why its so bad after all. (RTC shifts to large? too high interrupt
>load? bad cables? Bad ZAP Settings? something like that...)
>
>
>And, yes: [X] iam aware that faxing over PCs or alaw/ulaw voip is far
>from being optimal.
>
>
>Thanks for any enlightenments.
>  
>
When you are truly aware how non-optimal faxing over a VoIP channel is, 
you will give up. :-) This isn't a joke. Its the best advice I can give. 
Some people will tell you they have something that works. Well, lucky 
old them. Its not a reliably reproducible phenomenon.

I assume the fax<->misdn<->zap<->fax path has a Digium TDM card between 
zap and the fax machine. If so, this is another configuration which 
seldom works. Some people seem to have success, but again its not 
reproducible. There is something screwy with either the TDM400 card or 
its driver.

Regards,
Steve