i went to the website, dialpad.com, but there wasnt much there. does anyone know?
Check out my site:
Chief’s Domain
There are devices to translate IP-type phone calls (Internet type) to circuit-switched (classic phone type calls), generally referred to as gateways.
They must have a bunch of these, perhaps situated in most major cities of the US. The call likely goes as IP as far it can, to avoid tolls, then as the last step goes through a gateway.
This is of course all speculation.