Faxing over Sip trunks with Edge

[cayres1003]

Has anyone been able to get faxing to work over Sip trunks - specifically Edge. I know their official position is that they do not support faxing. But Has anyone been able to find the right combinations of settings to make it work without going to an external device?

 

[belevedere]

What system is this?

 

[cayres1003]

I have a 9100 setup in netlink. I have sip trunks to edge. I can get the faxing to work without any issue between the campuses - each campus has a cabinet with an analog card for the fax machine. But faxing out and in has been super problematic.

 

[belevedere]

NEC strongly suggests using analog trunks for faxing, however, try looking at these settings;
84-34, select SIP trunk at the top right, under profile 1, 01 = RFC2833, 02 = 101 or 110, we use 101. We also use G.711 only in 84-13-28. If changes are made a system reset is probably required.

 

[cayres1003]

I am already good to go on these config settings.
Also, I have turned off 84-33 profile 1 for sip trunks after learning of edge not supporting faxing. But I wonder if there's not some settings in there that might could help. 84-33-02 has 4 different settings - which if they are in a manual somewhere, I apparently don't have that manual. I am going to just play around with those settings and see if I can get something going.

 

[belevedere]

84-33-02, 0 = R/U, 1 = U/R (default), 2 = RTP, 3 = UDPTL. That's all I have on it.
You could try slowing it down with 84-33-06. 2 = V.17, 14400bps (default), or 1 = V.29, 9600bps.
Also 84-33-10 T.38 TCF Method, 2 - G3FE (default) or 1 - VOIPDB

 

[cayres1003]

yeah me too. But does R/U or U/R or RTP represent in terms of faxing? That's one of my questions

 

[cayres1003]

typo
meant to say but What does ....

 

[belevedere]

Don't know, but those options are listed under the SIP faxing MB's. It comes down to trial and error. You could contact NTAC and see if they have any definitions.

 

[cayres1003]

yeah. I think I will. I am having some pretty good success with turning on 84-33 for sip trunks and setting option 19 to type 2. I also have some options on the fax machines for Voip faxing compatibility mode which has helped too. Time will tell.