What is special about VOIP is that it's just another thing you can do on the Internet, whereas it is the only thing - or nearly the only thing with the exception of the dial-up modem and fax - that you can do on the public switched telephone network.
Vinton CerfI think imaginative exercises can have a profound impact on the future - what you can imagine can sometimes turn into something you can figure out how to build.
Vinton CerfI'm projecting somewhere between 100 million and 200 million computers on the Net by the end of December 2000, and about 300 million users by that same time.
Vinton Cerf