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[Business] Is Comcast Business Voice VOIP? How reliable for busi

We want their internet, but they want $4,000 to build out to our area. If we choose to subscribe to their voice/internet package the build out is only $300.

We don't want VOIP, as we have ATT land lines and we're satisfied.
Their sales rep stresses their phone service is not VOIP; it's EMTA.

But EMTA is just the box that houses the voice adapter/cable modem. So I don't understand her.

Secondly how reliable is Comcast Voice for business? We need 12 lines. We need to make international calls, and we need these lines to be just as reliable as our ATT lines (up 99% of the time).

Schuylkill Haven, PA

Re: [Business] Is Comcast Business Voice VOIP? How reliable for

CDV (Comcast digital voice) is very reliable, but it isn't going to match POTS lines for reliability. CDV will save you money, so consider getting maybe 8 lines and keep a few POTS lines.

CDV does use the Voice over IP protocol, but it is technically different than over the internet VoIP like Vonage. I'm guessing that's what your rep is trying to tell you.


Rochester, MI
reply to ThomasC
It is generally a reliable service. Since you don't want it, see if you can work closely with your rep to get rid of that $4000 connect fee. It was $10,000 to build out to the last company I consulted for that decided on Comcast. They signed a two year contract and got two internet connections and they waived all 10 grand. We decided against cdv only because voip with a pstn backup made much more economical sense. The voip has been down once for 5 minutes in the past year, and that's because Comcast was down. They've saved a boatload over their old ATT bill.


reply to ThomasC
Yeah if you signed at least a 3 year deal with 22x5 or better we'd usually waive 3 grand in construction. Just play hard to get and I'm sure they will work with you more.

reply to ThomasC
I can tell you from experience that my voice service had one outage that lasted less than 2 hours in three years. Before then, I had Verizon for almost three years. I had an outage with them that lasted about 6 days.

It's VOIP. However, it's not relying on the public internet. All voice services travel on Comcast's private network until it hits the Bell switches. The difference is that the dial tone originates from the eMTA installed at your site rather than a central office.

FWIW, the eMTA, along with Comcast's infrastructure, has battery backup in the event of power outages. As long as RF signal flows through your premise, you have service.


reply to ThomasC
CDV is a implentation of VoIP - but it's over Comcast's coax and unlike traditional VoIP you have a UPS integrated into the EMTA - which works like a VoIP ATA - but with coax instead.

I know of a business that runs CDV but they have a traditional AT&T landline with basic service for 911 calling since non-AT&T calls in California will get routed to the CHP.


Springfield, VT
reply to ThomasC
I switched from landline to CDV and find the quality alot better, with the landline we had alot of static and after switching we find the connection is more reliable and don't get "All Circuits Are Busy" any-longer besides other errors like that.


reply to ThomasC
Comcast CDV instead of using SIP uses NCS which allows much larger packet sizes hence the better quality audio.
And it's true the voice packets never hit the public internet they travel comcast's network and are allowed high priority at the CMTS and other routers. Not to mention the packets are buffered at the CMTS in case re-transmission is needed.


What is NCS?

The wings of love
Union, NJ
»en.wikipedia.org/wiki/Network-ba ··· ignaling