VoIP Softphones

VoIP softphones allow computers to become a virtual phone that is able to make and receive calls via Voice over IP services. They use both the software and PC hardware to ensure VoIP services. Soft phones also employ PC speakers or headphones and a PC microphone.

Softphones ensures making telephone calls over the Internet with the use of a computer. Quite often, soft phones are like traditional telephones but they usually do not need any hardware. Most often they appear as a phone image on the computer screen with a display panel and buttons. Users then can interact using this image. However, a headset or speakers and microphone - connected to the sound cars of the computer or with a USB - are needed (Figure 1).

basic concepts of softphone communication
Figure 1 - Basic concepts of softphone communication

Where you can use a softphone?

Softphones are most often used for making telephone calls over the Internet to other softphones or to traditional telephones. Usually service providers allow free calls between computers (PC-to-PC calls) but other versions (PC-to-phone or phone-to-PC) are not free.

Beside this typical usage, softphones can also be connected to a PBX (Private Branch Exchange) via LAN (local area network). In this case, the softphone works through an already implemented hardware phone. This means that the softphone controls and dials via this hardware. This option is widely adopted for call center solutions since it allows convenient services such as providing information on the screen about which customer is calling or about other important details. However, this kind of PBX is not allowed in some countries.

Basic softphone features

VoIP softphones are the software means that ensures you interaction while you use only the computer. They have an on-screen dial pad, a display for dialing and caller ID, an addressbook or contact list can also be included making dialing easier. They include all standard telephony features (DND, Mute, DTMF, Flash, Hold, Transfer etc) and a lot of new ones like Presence, Video, Wideband Audio and more.

Advanced softphone features

Due to their computer based structure, VoIP softphones can include several advanced features. Therefore, they can be integrated with chat or IM programs that are already widely used over the Internet. Enhanced display features can also be various to display call times and even durations, detailed caller ID, etc. They can also be integrated with further software and services to achieve more functionality such as videophone conversations, etc.


To be able to communicate using softphones, end users need to use the same communication protocol and at least one common audio codec. The most often employed protocols by service providers is SIP.

Find out more about protocols


The minimum codecs set is G.711, GSM and iLBC. More codecs description is available at: Codecs.

VoIP softphones offer a convenient and easy way for communicate and interact with other users, even for free. It is the ideal solution for those who works long hours on their computers in this way making calls will not require any additional device or service.

Find out more about codecs

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