Scenario#23 – Fax Issues for ATA

Fax machines connected to ATA were not working.

The first thing I checked on the gateway…is fax-relay was being used or fax protocol cisco was configured? Fax-relay is NOT supported by ATA.

This is what I found at the Voice gateway:
voice service voip
allow-connections h323 to sip
allow-connections sip to h323
allow-connections sip to sip
supplementary-service h450.12
fax protocol cisco

I found the reason why faxes were not working. Fax protocol cisco was used which enabled default fax-relay.

I configured the following:

voice service voip
fax protocol none {or could have configured modem passthrough nse codec g711ulaw}

dial-peer voice 40 voip
description **Outgoing Call to SIP Trunk**
translation-profile outgoing SIP-CALLS-OUT
preference 1
destination-pattern 9.T
voice-class codec 1
voice-class sip dtmf-relay force rtp-nte
session protocol sipv2
session target sip-server
dtmf-relay rtp-nte
fax rate disable <<<<<<
no vad

!
!

dial-peer voice 50 voip
description **Incoming Call from SIP Trunk**
translation-profile incoming SIP-CALLS-IN
preference 1
redirect ip2ip
voice-class codec 1
voice-class sip dtmf-relay force rtp-nte
session protocol sipv2
session target sip-server
incoming called-number .%
dtmf-relay rtp-nte
fax rate disable <<<<<<
no vad
!

Everything started working!