ABSTRACT
Voice over IP (VoIP) should not be considered as a disruptive service1 since it fundamentally does not offer the user any difference in service than before; in particular, compared to the old PSTN (Public Switched Telephony Network), for instance. IP networks, however, have the advantage of making it easier to combine basic voice services with advanced features, such as Instant Messaging (IM), file sharing, video communications, and more. is generates a major opportunity for competitors to enter the market with relatively little cost and minimal risk involved.
