sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services Telecom Service & Providers Faxing via Comcast PRI

Comcast has given us a very attractive price for a PRI, with unlimited in-state long distance and 4,600 minutes of inter-state long distance monthly included. As our current AT&T long distance bill runs about $3,000 per month, adding this circuit for outbound toll calls alone would more than pay for it.

The catch? Faxes. Comcast says faxing via PRI isn’t supported, but many of their customers do it with no problem. With 1,200 to 1,500 faxes sent per day, that’s the majority of our toll calls.

I’m not willing to give up the reliability of my AT&T PRIs just to save money, so we would keep them for inbound traffic and fail-over for outbound toll traffic.

Anyone have any experience with faxing over a Comcast PRI? Again, it’s an attractive offer.

With that amount of faxes going out it must be a pretty major part of your business. Is it worth your savings to have 2%, 5%, 10%, of faxes fail? I am not saying that many will fail, but if Comcast is telling you that it is not supported then there must be a good reason.

Steve

No, saving $25,000 a year isn’t worth the hassle of lost faxes. But if someone has any experience with this, I’d like to hear about it.

This isn't because of it being a Comcast PRI. It is because they are using VoIP in their switching. You might try asking them if they have a real switch, like a 5ESS or DMS in their network that they can use to provide the PRI service. If they can do this, you probably won't have any issues at all.

All they have is VoIP, and I'm guessing that I'm out of luck.

Before I nixed the deal, I thought that I'd ask around.

I only have one customer with a Comcast PRI but they have absolutely no problems with their faxes.
But then I don't know what kind of switch they have serving the PRI.

Bill

PRIs from Comcast are most likely using VoIP/SIP protocol, which can be unpredictable with faxing.
I assume the PRI from AT&T is TDM based, which is a legacy protocol used for 50+ years. Land lines (POTS) are TDM.

Comcast states they don't support faxes because it may work and may not. Packets can become garbled and lost, especially when sending a high number in succession.

I work with carriers that state they don't support VoIP calls, although it may work ok in general. It's kind of like just a CYA for the carrier to not make any guarantees.