Nowadays technology is playing an imperative role in our lives and every aspect of our lives have been influenced by it. The set of rules that are used for discourse data over a packet switched internetwork by using the rules and regulations of World Wide Web are referred to as World Wide Web protocol or transaction control protocol/internet protocol or internet protocol. 

The technology that permits us to utilize the internet like a buzz system along with some supplementary competence rather an analog telephone line is called as 'voice over internet protocol'. Different VoIP provides different range of amenities. Some authorizes us to call anybody who has a dial up number plus local, cellular, and international dial up numbers whereas other VoIP services only operates on our computer system or a particular VoIP phone. Further services authorize us to utilize a conventional telephone linked to a VoIP adapter. 

Standard list is available that surrounds all the Linux resources. The elements within the list are CentOS, Debian, Fedora, Gentoo Linux, Pie Box, Red Hat, Slackware, SUSE, Tao Linux, Ubuntu, Whitebox, and Yellow Dog Linux. We may consider this list prior to make a selection to open source product that grants us a pleasant bond with our VoIP application. The compatibility of a particular VoIP application varies with the operating system. 

There is a large range of voice over internet protocol applications e.g. Asterisk, CallWeaver, Ekiga, KPhone, Linphone, OpenPBX (Voicetronics), PhoneGaim, SIP Express Router (SER), sipX, sipXphone, sipXezPhone, Skype, and Twinkle.

Callweaver was initially originated form Asterisk. It is a full attributed open source PBX scheme that supports analog, digital telephony, and various VoIP. Ekiga is an open source application for GNOME. H.323 and SIP are the two set of rules and regulations, which are used by Ekiga. Ekiga is well suited SIP, H.323, STUN, and Zeroconf and supports numerous audio and tape files.

Skype is the trendiest protocol. It is used nearly in every part of the world and utilizes Peer to Peer process. Skype is accessible in twenty eight languages. SIP is another open source product. For Linux, the SIP PBX is steady and unconfined along with its more than one hundred and seventy new features.

Twinkle employs SIP protocol. Open source software for VoIP system is PhoneGaim. Linspire sponsored PhoneGaim and obtainable under the GNU General Public License. SipXphone is a Java based SIP softphone for both Windows and Linux. Its operational way and graphical user interface are very similar with each other. Hardware conceptual level was used to wharf from the inventive VxWorks operating structure to Windows.

A complete attributed execution of a SIP softphone is resulted from the Pingtel xpressa JAVA softphone. sipXezPhone and sipXtapi are constructed to be podium and functioning structure atheist. For SIP protocol, multitudes of features have been supported by KDE supported softphone. Until 2005, it was advanced at Wirlab but now a group of volunteers in a SourceForge venture developing it. SIP, STUN and SRV are its well matched protocols.