I have charter installing two PRIs for voice services. I have a Adtrans for th fax lines in building A but need to get fax lines in building B. I was going to try to use a grand stream HT701. I was going to create a extension and send it to the ht701 and plug it into the fax machine. Charter says they only support cored G711 and not t.38.
Has anybody every done this or have any suggestions.
PRI’s are by definition only G711, inbound faxes will always use T30,T38 is only possible for IP connections, With a fiber connection between sites, then using a SIP transport between sites should work fine with T30 over G711 (for that matter, so would an IAX2 tie-line) , your ATA’s will just pass the T30 signalling directly to the Fax device.
Dicko is right - inband works great with those. It’s funny too - the Adtrans do T.38 PERFECTLY - Every time I find an abandoned Adtran I cackle like a fool - they are really expensive, but Adtran support is awesome and flashing them up to current and using them as an 8-Port ATA (we mostly find 908 and 908e’s) works great. So great if you have inband, REALLY great if you have SIP trunking.
So using the ht701 as an extension will work for faxing over the fiber to another building
I believe I already said:-
PRI’s are by definition only G711, inbound faxes will always use T30,T38 is only possible for IP connections, With a fiber connection between sites, then using a SIP transport between sites should work fine with T30 over G711 (for that matter, so would an IAX2 tie-line) , your ATA’s will just pass the T30 signalling directly to the Fax device.
did you try it?
Non haven’t yet was planning on this week. PRI should be on tommorrow for testing
I setup the HT701 and set it up for ext 700. Then configured the inbound route for the fax number to ext 700.
I then send and received a fax with no issues. Should I be cautious of any issues in the future.
My experience with FAX tells me “Yes, you should.” There are MANY different manufacturers of FAX hardware and software out there, and not all of them “do the right thing” every time.
That fact that it’s working is the easy 90%. I wouldn’t worry, but I would expect the occasional weird FAX problem. Not because of Asterisk or your setup - just because that’s the nature of FAX solutions.Note that this is the same advice I give people when they are using regular FAX machines.
Thanks for the Reply Dave
Greg,
Are you referring specifically to faxing on the 908s? We are about to purchase a 916 and use it for 5 fax machines. Our lines are PRI into a Sangoma Dahdi card, which would then convert to SIP to the 916 where the fax machine is connected.
You have a lot of success with this setup?
Yes - It’s a combination of the superior Adtrans, and Asterisk with SpanDSP has finally matured to the point that it is seamless.
Two recent success stories:
A local clinic - 7 FAX machines hanging off a 908e - each machine sending 75-150 multi-page FAXes a day, so probably well over 2000 pages FAXed per day - flawless.
A local Condo-Resort - 4 Adtran 924e devices servicing the rooms and the FAX machines in the business center + the Office - over 80 active FXS Ports!
I love the Adtrans so much - when I find an abandoned one I practically wet myself - they are really expensive, but they are SOLID!
Awesome thank you, you typically do these with PRI or SIP trunks?
We are using both, but primarily SIP trunks nowadays - but they work great with both.
Rant Coming…
Not all PRI’s are created equal - their are two types of PRI’s you will encounter and they are very different as far as quality for FAX:
True TDM PRI’s - These come from your incumbent LEC or are resold through a CLEC, but they are true TDM Digital PRI’s that are true TDM PRI’s back to the CO - They work perfectly.
Fake PRI’s that are created with an IP circuit feeding a device (Often an Adtran) that converts them to a TDM PRI - these in our experience are NOT as good as the true TDM PRI’s although they are getting better.
So, if you get the PRI in, and everything else is set up correctly and you are having problems with FAX, make sure it’s a real PRI and not a faked IP-PRI.
Thanks for the info! We definitely have a true PRI, been in place for many many years, and done faxing with it for a long time. Just finally moving the pots lines off of the old Cortelco onto the Adtran. Then in a year when the PRI contract is up we will go all SIP at this site.
Just went live yesterday on the PRI from Charter Communications and Faxing works flawless with the HT-701s. I have about 10 of them at the remote sites via 1GB fiber links