It is a call which is made over internet protocol (VoIP). For example, one can call using Google Voice to other recipient located miles away. Such call can also be international.
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.
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