Re: V17 vs V34, MSANs and faxanswer

On Wed, Jun 6, 2018 at 11:30 AM, Christo Labuschagne
<[email protected]> wrote:
> Good day all
>
> We have a problem on a line (that is very far away and not manned by a
> specialist) where sending a fax works fine but we cannot receive a fax.  It
> answers but does not want to train or trains at 2400 and then no data gets
> through.  A V17 fax machine works fine though.  After a lot of studying of
> how network infrastructure works, we have learned that networks use CED or
> /ANSam to open up the channel with either T.38/G711 for CED or G711 for
> /ANSam.
> Do you guys have any idea if this is correct?


My experience is by no means exhaustive, but I jhave not experienced a
telco that does tone detection on calls, I have seen "fax splitters"
that do tone detection so a fax machine and a telephone can share a
line.

>
> If it is correct, have you ever had lines that does not support /ANSam?
>
> The same modem can be connected to various interfaces, so in some cases we
> would like to answer with V17 (PSTN) and in other cases V34 (PABX).
> faxanswer does not have an option to specify a speed limit like sendfax has
> with -B.  The only way I could limit the answering fax modem to answer with
> CED is to remove the Class1EnableV34Cmd from the config.
> Is there a way to configure the answering mode (CED or ANSam) on the fly?

I don;t follow what you mean by "interfaces" in this sense, and also
do not follow why you have ascribed V17 to PSTN and V34 to PABX

https://en.wikipedia.org/wiki/List_of_ITU-T_V-series_recommendations

What model modem is this ?

>
> I'm trying to get as much info ready before we go out and try and fix the
> problem.
>
> Running Linux btw.
>
> The one option I have is to create a symbolic link to the same modem and
> then have two config files.  I could then start the same modem up depending
> on the interface and then just call faxanswer with the correct modem, but
> this would cause a modem reboot for at least one interface (idle in V34 mode
> and then stop hylafax for that mode and then start it for V17 mode if a call
> comes in on a different interface).  Not elegant, but an option.
>
> Thanks again for a great product!
>
> Kind regards
> Christo


____________________ HylaFAX(tm) Users Mailing List _______________________
  To subscribe/unsubscribe, click http://lists.hylafax.org/cgi-bin/lsg2.cgi
 On UNIX: mail -s unsubscribe [email protected] < /dev/null
  *To learn about commercial HylaFAX(tm) support, mail [email protected].*