[cisco-voip] [EXTERNAL] Re: Faxing over CUBE SIP Trunks

[Kent Roberts]

Basically let the cube stay out of it.  From my understanding and to keep it simple since there’s is a lot…. When the call goes to the sever and starts the fax it will ask to go to t38. This request will be sent to the far side to also switch to t38.   Should that fail the call would go to 711 or possibly stay at 711 depending on how your codecs are setup.   The idea is to just let the cube pass t38 traffic if it sees it. Outside of that it’s just another normal call.

As for 9600 question.  I would go on the server side.  It’s probably easier to update a server then play with the cube all the time.  With the traffic I deal with cube is mostly set and forget unless we have to touch it.   But with all that said you may have to try a few different things to find the best working possible setup for your vendors products.  9600 would be fine for a standard fax.  Little slow but would work. 14400 and color kinda went together but color never really made it. Guessing cost of color at the time for what fax provided….  

Keep in mind that if you limit fax to 9600 on the cube it might ( not saying it will) have impact on a 14400 modem if you still use them and a cng tone gets detected.   But who uses modems anymore….

Kent

> On Jun 22, 2021, at 07:15, JASON BURWELL <JASON.BURWELL at foundersfcu.com> wrote:
> 
> 
> Thanks Kent,
>  
> A couple follow up questions, if you don’t mind? You mentioned the fax server had G711 fallback enabled but you have it disabled on the CUBE? Does that not cause any G711 fallback attempt by the faxserver to fail?
>  
> Also, do you recommend setting the fax rate to 9600 on the CUBE or leave the CUBE 14400 and limit that on the fax server?
>  
> Thanks!
> Jason
>  
> From: Kent Roberts <kent at fredf.org> 
> Sent: Monday, June 21, 2021 7:31 PM
> To: JASON BURWELL <JASON.BURWELL at foundersfcu.com>
> Cc: cisco-voip at puck.nether.net
> Subject: [EXTERNAL] Re: [cisco-voip] Faxing over CUBE SIP Trunks
>  
> CAUTION: This email originated outside of Founders Federal Credit Union. Do not click links or open attachments unless you recognize the sender and know the content is safe.
> sure.   This is what we had to do to get fax working for use on both vg’s. (202/322/fxs) and Rightfax/brook trout cards) 
> Rightfax has the g711 failback enabled.   IE it controls it not the cube.
>  
>  
> Under voip service voip..
>  
> Fax protocol t38 version 0 ls-redundancy 0 hs-redundancy-fallback none
>  
> sip
> Midcall-signaling passthru
> header-passing
>  
> And the dial-peers towards the carriers:
> fax-relay ecm disable
> fax rate 14400
>  
>  
>  
> Good luck.  Fax is an easy but fun/tough thing to make right.         Put Wireshark on your server, it helps.     Also, ,might need to force the max fax rate to 9600.   
>  
> 
> 
> On Jun 21, 2021, at 12:26 PM, JASON BURWELL via cisco-voip <cisco-voip at puck.nether.net> wrote:
>  
> Can anyone offer some guidance doing faxing over SIP Trunks? Ever since switching to CUBE SIP trunks I’ve been having challenges with outbound faxes. With one provider, it rarely works, the other it works most of the time but is not reliable. Sometime it fails and I resend it and works fine. I have an Xmedius Fax Server using T38 with G711 fallback. Feel like I am missing something, I’ve had a few cases open and a mix of fingerpointing (XMedius/Cisco/Provider) and dead ends but no solid resolution. Just figured I’d ask out here before I escalate these cases again. Both providers use G711 codec on the trunks. When I point the calls pack to MGCP PRI I have no issues.
>  
> Thanks
> Jason 
>  
> _______________________________________________
> cisco-voip mailing list
> cisco-voip at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-voip
>  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://puck.nether.net/pipermail/cisco-voip/attachments/20210622/48757d19/attachment.htm>