Page "Voice over IP" Paragraph 16

A major development that started in 2004 was the introduction of mass-market VoIP services that utilize existing broadband Internet access, by which subscribers place and receive telephone calls in much the same manner as they would via the public switched telephone network ( PSTN ).

Full-service VoIP phone companies provide inbound and outbound service with Direct Inbound Dialing.

Many offer unlimited domestic calling for a flat monthly subscription fee.

This sometimes includes international calls to certain countries.

Phone calls between subscribers of the same provider are usually free when flat-fee service is not available A VoIP phone is necessary to connect to a VoIP service provider.

This can be implemented in several ways: