[Freeswitch-users] mod_openzap, sangoma, FAX and HW-HEC

Helmut Kuper helmut.kuper at ewetel.de
Wed May 12 09:47:56 PDT 2010

Hash: SHA1


I'm not sure whether I'm right here or not. But maybe someone has faced
same problem:

Scenario A:
I'm using Sangoma A104d and FreeSWITCH Version 1.0.head (17097:17188M).
I enabled hardware based detection of fax and dtmf. Further hardware
based HEC is enabled

I'm not able to reveive a FAX (analog) via PSTN, while sending works and
internal (SIP) works as well. So there is no problem with the ATAs I use
nor with the network (which routes the RTP along 80 kilometers one way).

Scenario B:
I'm able to receive FAX from pstn with same setup, but have hardware
based HEC disabled. So in this case everything works fine.

I thought sangoma's hardware based Fax detection feature should have
disabled HEC when a Fax is detected, but it doesn't seems so. So my
current thoughts are about the question whether FS is able to disable
hardware HEC via mod_openzap and wanpipe driver for the corresponding
A104d channel, when FS knows that the target is a FAX device ...

Version: GnuPG v1.4.7 (MingW32)


More information about the FreeSWITCH-users mailing list