asterisk users - Jun 2005 - * fax reliability between ISDN PRI and FXS ports

Hi, 
 
I am building for a customer an * solution that will use 2 Digium cards.
 
1 x TE110P (T1 ISDN PRI)
1 x TDM40B (4 analog ports, 2 for faxes, 2 for extensions)
  
The system will be connected to the PSTN through the T1 ISDN PRI interface.
All customer extensions will be SIP phones except 2 fax machines that will
use the analog FXS ports on the TDM40B card.
 
I have been investigating on this list and found that faxing is not reliable
between Zaptel cards and that Digium does not support nor recommend fax over
the TDMXXB interfaces.
 
Is this true ?  Will fax not be reliable enough for my customer ?

Will it be better to use Audiocodes digital and analog gateway (ATA) with
T.38 capabilities ?  
 
Thanks in advance, 
                Andres Maduro
 
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
http://lists.digium.com/pipermail/asterisk-users/attachments/20050625/33d1b39d/attachment.htm

I plug my fax machine into a Grandstream ATA286 (No T.38).  Works fine for me
and has done for the last year.  I can send and receive 40 page faxes without
issue.  The ATA286 is located on the same LAN as the Asterisk.

Craig


---- Andres Maduro <andres@iconos.com.ve> wrote: 
> Hi, 
> 
 
> 
I am building for a customer an * solution that will use 2 Digium
cards.
> 
 
> 
1 x TE110P (T1 ISDN PRI)
> 
1 x TDM40B (4 analog ports, 2 for faxes, 2 for
extensions)
> 
  
> 
The system will be connected to the PSTN through the T1 ISDN PRI
interface.
> 
All customer extensions will be SIP phones except 2 fax machines that
will
> 
use the analog FXS ports on the TDM40B card.
> 
 
> 
I have been investigating on this list and found that faxing is not
reliable
> 
between Zaptel cards and that Digium does not support nor recommend fax
over
> 
the TDMXXB interfaces.
> 
 
> 
Is this true ?  Will fax not be reliable enough for my customer
?
> 
> 
Will it be better to use Audiocodes digital and analog gateway (ATA)
with
> 
T.38 capabilities ?  
> 
 
> 
Thanks in advance, 
> 
                Andres Maduro
> 
 
>

> I am building for a customer an * solution that will use 2 Digium cards.
>  
> 1 x TE110P (T1 ISDN PRI)
> 1 x TDM40B (4 analog ports, 2 for faxes, 2 for extensions)
>   
> The system will be connected to the PSTN through the T1 ISDN PRI interface.
All customer
extensions will be SIP phones except 2 fax
> machines that will use the analog FXS ports on the TDM40B card.
>  
> I have been investigating on this list and found that faxing is not
reliable between Zaptel
cards and that Digium does not support nor
> recommend fax over the TDMXXB interfaces.
>  
> Is this true ?  Will fax not be reliable enough for my customer ?
True... the TDM card (or its drivers) has an issue with missed frames
that seriously impacts its ability to handle _any_ modem-type calls.
> Will it be better to use Audiocodes digital and analog gateway (ATA) 
> with T.38 capabilities ? 
A good ATA should work fine, but you should probably test it before
exposing your customer to potential problems. Others have used ATA's
with analog fax machines.