Where are these calls terminated? I ask because I am always concerned that these sorts of services are being monetized by pumping traffic[1] into Iowa.
Can you maybe elaborate on how you're getting paid from termination? Perhaps I abused the term "traffic pumping", but this definitely sounds like the sort of of thing I was picturing being exorbitantly expensive to the carrier initiating the call to your service.
I previously worked as a telecom engineer at a VoIP startup and we definitely characterized http://freeconferencecall.com as a service monetized by traffic pumping and denied connecting to its NPA in our dialplans. While by no means absolute truth, the concern I'm voicing is further reinforced should it be true that Google Voice is refusing to terminate to your DID as described below.
Hey again-- I've actually made a response on the related reddit posting to a similar question. I typed out a fairly in-depth response, so I'm going to paste it below.
I hope this clears things up.
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Basically--we partner with telephone companies who colocate our equipment (servers, etc.) which we use to run our software. We purchase phone lines from these telcos (to support incoming calls), and then provide free services for public consumption to make money off the termination cost.
Imagine that you have a T-Mobile cell phone, and your friend has a Verizon cell phone. When your friend calls you, Verizon pays T-Mobile a small amount of money for every minute that your call lasts (this fee is to pay for the physical infrastructure that T-Mobile invests in--telephone polls, switches, service monitoring, etc.). That's why cell phone plans cost money and aren't free.
We operate the same way, except we partner with telephone companies (like T-Mobile in my example above), and split the termination fees with them.
So the more people use our services, the more we can profit from it.
Hopefully this clears it up. There's been a lot of discussion in the internet recently about traffic pumping and companies attempting to get fraudulent traffic to make money. We are by no means doing anything illegal or illegitimate here.
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Also: our motivation for building confnow is to basically to make conference calling as simple as humanly possible. I've personally used the other sites out there (namely: freeconferencecall.com), and nothing is more frustrating to me (as a user) to want to make a quick call and have to go through hoops (setting up accounts, waiting for verification, listening to ads, etc.) when you just want to get into a room as quick as possible and move on with your life.
What makes you feel confident about this? The assertion that "We get paid from termination" strikes me as very much that sort of arrangement. Perhaps I'm abusing terminology.
[1]http://en.wikipedia.org/wiki/Traffic_pumping