Softphone

A softphone is a computer program that enables telephony. A distinction is made between PSTN software for fixed telephony and Internet telephony software.

Applications

Provider of VoIP services often provide a softphone available, where they differ is usually very limited in features. In addition to the open standard SIP (eg Gizmo5, Jajah, KPhone, Linphone, Nimbuzz, Phoner, QuteCom, X - Lite), H.323 (eg Ekiga, NetMeeting, OpenH323 ), XMPP (eg Google Talk) and IAX (eg Parlino ), proprietary protocols are widespread (eg Skype ).

For fixed telephony, there are programs that accept only the dialing the number (eg, the Windows Phone Dialer ), while the actual calls a conventional telephone is needed - these pure selection programs are sometimes referred to as a softphone (or dialer software ).

Requirements

To use a softphone, you need a network connection, in the case of PSTN via an associate with the ISDN or analog network connection device such as an ISDN card, a telephone modem or a terminal adapter, in the case of Internet telephony via a (possibly broadband ) internet access ( depending on the compression, voice quality and transmission protocol at least ISDN). Further, a microphone and speakers, needs, also known as headset (headset ) can be combined. Finally, a sound card must be present. There is the possibility externally powered sound card in case of a telephone handset, which are connected via the USB port to the computer and used as a traditional telephone handset. About default driver and the settings of the most softphones, it is possible to assign separate sound cards softphone applications and other application programs.