Harshada Jagtap, Prof. D.G.Gahane
A telephone conversation can be done over a data network byVoice over Internet Protocol(VoIP). VoIP products are cost efficient, more versatile and also provide good voice quality as compared to proprietary system and promise converged telecommunication and data services. This paper describe Internet Protocol Private Branch Exchange (IP-PBX)calling on smartphones. IP-PBX is a complete telephony system that provides both wireless and wired calling without using SIM card. IP-PBX server is implemented by using CentOS Linux based operating system where Asterisk open source package is used. By implementing IP-PBX server wireless communication can be done in WIFI range using laptops and smartphones