Fax over IP between IPOffice and CM

[auskar85]

Recently I configured H.323 trunk between CM 4.0 and small office. However fax doesn't go through IP. I tried changing fax relay to pass-through on CM. I also tried turning off caller display type on IPOffice. I also tried fax transport support check box. Fax beeps and there is nothing more. Are there possibilities to use fax over IP with no problems at all?

 

[tlpeter]

H.323 and faxing is not a good solution.
Your only gamble is using G.711 as the codec.


BAZINGA!

I'm not insane, my mother had me tested!

 

[auskar85]

First I set it to Automatic Select on IPoffice. Then I set to G.711u. I was not working at both times.
Let me ask, whay then relay protocol is supported if it is not working?

 

[intrigrant]

Fax over H.323 will fail 100% Either use SIP ATA's on both side or SIP trunks with T.38 support

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[auskar85]

T.38 is not a call setup protocol, thus the T.38 devices need to use standard call setup protocols to negotiate the T.38 call, e.g. H.323, SIP & MGCP.

This is from wikipedia. So it should work over H.323

 

[tlpeter]

No it does not.
T.38 is not available on a h.323 trunk.

BAZINGA!

I'm not insane, my mother had me tested!

 

[amriddle01]

Come on Peter, it's on Wikipedia...it must be true


Avaya Implementation Qualified Professional Specialist Technical Engineer (AIQPSTE)

 

[amriddle01]

If you look below you will see in all scenarios SIP is used for T38

Avaya Implementation Qualified Professional Specialist Technical Engineer (AIQPSTE)

 

[auskar85]

Hmm. What I found on manager help:

The H.323 Stack within the core software supports the following protocols:-

· H.323 (V2)(1998), Packet-based multimedia communications systems

· Q.931, ISDN user-network interface layer 3 specification for basic call control

· H.225.0 (1998), Call signaling protocols and media stream packetization for packet-based multimedia communication systems

· RTP/RTCP

· H.245 (1998), Control protocol for multimedia communication

· Audio CODECs:

· G.711 A-law/U-law

· G.723.1 MP-MLQ

· G.729 Annex A - CS-ACELP (Not supported by NetMeeting)

· Silence Suppression

· Fax Relay

· Local End Echo Cancellation 25ms (except transparent - no cancellation)

· Out of band DTMF

· Internet Standards/Specification (in addition to TCP/UDP/IP)

· RFC 1889 - RTP/RTCP

· RFC 2507,2508,2509 - Header Compression

· RFC 2474 - DiffServ

Relay should be supported on 4.2, if T.38 is not.

 

[amriddle01]

It is not the same thing and uses 2 VCM channels per call


Avaya Implementation Qualified Professional Specialist Technical Engineer (AIQPSTE)

 

[auskar85]

So what is fax relay?

 

[auskar85]

Fax Transport Support: Default = Off
When selected, this option provides support for faxing over a H.323 connection to another IP Office with the same setting.

What about this statement? Does it mean fax is supported between IPOffices only?

 

[intrigrant]

Fax support on H.323 trunks on Avaya IP Office use a propriate protocol build by Avaya and only available on IP Office so you cannot use that between other systems as IP Office.
T.38 is a SIP industry sub FoIP protocol supported by nearly any vendor and is THE protocol to use for Fax over IP.

Said that I advice you to use SIP, either SIP trunks or SIP ATA's supporting T.38.
That is the only path to get (reliable) faxing between the different systems using a IP connection.

BTW Wikipedia is a resource as reliable the person who wrote it and the resources used to base the article on it. The good thing is that if you experience there is something wrong in the article you can edit it.

A simple mind delivers great solutions

 

[auskar85]

The problem is that there are no SIP trunks on CM system-parameters customer-options.

 

[intrigrant]

No there is not, it is configured in the session manager. but not all CM systems do have that so that is why I suggested a ATA, that connects to a anlog station on CM, then connects over SIP to another ATA which connects to a analog station on the IP Office.
Considering licensing and such things the twe ATA's may be as expensive as one license for IPO not to speak about a CM license.

A simple mind delivers great solutions

 

[auskar85]

CM version is 4.0, so there is no session manager. The problem is that there are more than 20 H.323 trunks with small offices. Do that means I need 20 ATA's?

 

[intrigrant]

.... if each site has a FAX, yes. Why don't they buy a decent Fax Server and integrate it in outlook?

A simple mind delivers great solutions

 

[auskar85]

I make it work without ATA today. According to:
Global IP Office Technical Tip
117: IP Office to ACM Fax over IP Interoperation
*Release Date: 20 Jan 2006,

I set fax and modem off on ip-codec set, because IP Office protocols and CM protocols are different. Also I turned off fax transport support on small office.

 

[intrigrant]

That techtip suggest you to "For T.38 support between IP Office 3.0 and higher releases and ACM, 3rd party T.38 gateways should be used in order to ensure compatibility." use a ATA as it is a 3th party T.38 gateway.
But be a wise guy and do as you please...

A simple mind delivers great solutions