Fax - VG224 - MGCP

[nellocon4]

Hi Folks,

I have setup a VG224 via MGCP and it is registered to the call manager. When I dial the DDi number I have assigned to the port internally I can hear the Fax machine (analog dial up tone). However, when I try to dial the number externally, the fax machine rings once, and then answers but is just silent...

Any ideas why the fax will not work when coming in through the PRI line?

My config on the gateway is as follows and is the same on the VG224...

mgcp

mgcp call-agent x.x.x.x 2427 service-type mgcp version 0.1

mgcp dtmf-relay voip codec all mode out-of-band

mgcp rtp unreachable timeout 1000 action notify

mgcp modem passthrough voip mode nse

mgcp package-capability rtp-package

mgcp package-capability sst-package

mgcp package-capability pre-package

no mgcp package-capability res-package

no mgcp timer receive-rtcp

mgcp sdp simple

mgcp fax t38 inhibit

mgcp rtp payload-type g726r16 static

mgcp bind control source-interface Loopback1

mgcp bind media source-interface Loopback1

[acampbell]

Shane,

From what you are showing here , you are running fax passthrough.

Your incoming gateway has to be configured to match this type of signalling.

If your gateway is H323 then you need to add a few lines of config.

!

Voice service voip

modem passthrough NSE codec g711ulaw

!

You can add this at dial peer level to be more granular:-

!
dial-peer voice 11 voip
description ### VOIP DIAL PEER TO CALL MANAGERS ####
preference 1
destination-pattern 6......
incoming called-number .
voice-class codec 1
voice-class h323 1
session target ipv4:10.182.182.12
dtmf-relay h245-alphanumeric
ip qos dscp ef media
ip qos dscp cs3 sig
modem passthrough NSE codec g711ulaw
no vad
!

HTH

Alex

[shane.oconnell]

Thanks for the reply!

I am running both the VG224 and the voice gateway on MGCP. So I beleive the incoming gateway is also running fax passthrough as the commands posted above are on both devices...

Is there a way I can check if I am running fax passthrough?

[acampbell]

Shane,

So you reckon your incoming gateway is also MGCP.

Check for these statements under the MGCP sevtion.

!

mgcp modem passthrough voip mode nse

mgcp modem passthrough voip codec g711ulaw

!

HTH

Alex