[asterisk-users] Fax from FXS to PRI

[Kevin P. Fleming]

On 09/20/2011 03:43 PM, Adam Moffett wrote:
> If I have a 4 port Digium FXS card and a single port PRI card on the
> same asterisk box, is it expected that I'd be able to plug a fax machine
> into the analog FXS port and have no problems sending or receiving
> faxes? Our connection to the Telco is on the PRI obviously.
>
> I don't recall the specific card models that we have, but I can check if
> it matters.
>
> Does the version of asterisk or Zaptel matter?

You need to be using DAHDI, not Zaptel, as there have been a lot of 
improvements in DAHDI as a result of Digium spending a great deal of 
time testing the exact scenario you outlined (and related ones). In 
addition, you need to be using a recent enough version of Asterisk to 
have the 'faxbuffers' configuration option available in chan_dahdi.conf, 
so that channels transferring FAXes can be configured with extra 
buffering to provide an insurance policy against timing slips.

-- 
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
Jabber: kfleming at digium.com | SIP: kpfleming at digium.com | Skype: kpfleming
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
Check us out at www.digium.com & www.asterisk.org