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VoIP is the abbreviation of Voice over Internet Protocol. VoIP technology you can make international phone calls but with lower costs than traditional phone system. VoIP provideer and a VoIP software. Also if you want , you can use a VoIP phone: it looks like a classic phone but instead it is connected to a VoIP provider through a Ethernet port and with the internet connection you can make local all bangla book pdf free download international phone calls with the help of the IP Phone.