3.1 Introduction
3.2 Scenario 1: Long-distance least cost routing
3.2.1 Least cost routing - an example of an implementation
3.3 Scenario 2: Alternatives to legacy PBX systems
3.3.1 Scenario 2a: IP Phones without a PBX system
3.3.2 Scenario 2b: Integration of VoIP with legacy PBX systems
3.3.3 Scenario 2c: Full replacement of legacy PBX systems
3.4 Scenario 3: Integration of VoIP and videoconferencing
3.4.1 Integrating voice and videoconferencing over IP - an example 4. SETTING UP BASIC SERVICES