If I install a VoIP system at my company headquarters, and then connect seven branches securely, I understand that my on-net calls will be "free". What about calls to other organizations' VoIP systems? What is the route between the systems and are the calls still free?
Generally they are not unless your telecommunications provider offers the routing as part of your service. Depending on your circuits and how you have your contracts set up, they may route your calls to a CO that is local to the number that you call. But that offering and the costs vary widely around the globe. There are several other things that you can do to minimize costs, for instance if you have several remote users, you can have them connect via softphones to the location with the lowest long distance service per minute costs. Generally this is FAR less expensive than calling cards, and in many instances local rates that you are probably paying now. It will also lower your 800 call-in costs for things like voicemail. So when you look at your options, think a little outside the box to be able to realize all your savings.