Free VoIP Software
VoIP Software Phone
Ekiga is an H.323 compatible videoconferencing and VOIP/IP-Telephony application that allows you to make audio and video calls to remote users with H.323 hardware or software (such as Microsoft Netmeeting). It supports all modern videoconferencing features, such as registering to an ILS directory, gatekeeper support, making multi-user conference calls using an external MCU, using modern Quicknet telephony cards, and making PC-To-Phone calls.
Software with VoIP telephone Solution
If you have a fast connection to the Internet (say 64kbps or more) you should consider Voice Over IP (VoIP) as a solution to your telephone requirements. This applies to Broadband, DSL and T1 connections. A normal broadband connection will allow many simultaneous VoIP calls.
Once you change to using VoIP you can install software to do the telephony work, including working as a PBX or telephone key system, call recording, voice mail, on-hold messages or simply to work as a telephone.
Skype is a proprietary peer-to-peer internet telephony (VoIP) network, founded by Niklas Zennström and Janus Friis, the creators of KaZaA. The Skype Group is headquartered in Luxembourg with offices also in London and Tallinn.
The system has a generally favorable reputation for working across different types of network connections (including firewalls and NAT) because voice packets are routed by the combined users of the free desktop software application.