The service offered by telephone companies allowing creating the telephone numbers on the same line where the existing number is. The call tone for every number will be different from another. There is also an opportunity to program a custom ring tone for the incoming call.
IDC projected over 9 billion minutes of voice traffic to travel over worldwide packet networks in 2000, exceeding 135 billion minutes in 2004. Service revenue is projected at 1.6 billion in 2000 and 18.7 billion in 2004.