Voice over IP (VoIP) is a set of software technologies that permit to establish and manage a communication audio not leaning to the normal telephone network, but to the Internet.
The reason for the growing interest that this technology is raising can be explained by the important benefits that its adoption can get compared to traditional telephony:
- Reduce operating costs;
- Reduced investment in infrastructure;
- Increase productivity with new features.
The first advantage, reducing operating costs, is significant mainly for calls that do not begin or end on a normal telephone users. If in fact the VoIP call takes place between two computers (PC, PDA or smartphone) connected to the Internet, you avoid any transit through the normal telephone network (PSTN: Public Switched Telephone Network). Therefore, nothing is due to telephone operators for communication between the parties and, apart from the costs already incurred by both to access the Internet, the call is absolutely free.
In this scenario, in fact, the call is not supported by a circuit created (paying) the telephone network to one or more managers, but from a normal network connection TCP/IP between two computers connected to the Internet, quite similar to that established between the Web browser and a Web server when you open Web page is simply not on that connection will travel texts and images from a Web site, but the digitized voice.
Another significant advantage is the reduction of investment in infrastructure, with the ability to replace traditional hardware switchboards (PBX) with simple applications VoIP software can provide a set of functions equivalent if not higher. VoIP applications that implement functionality of the PBX can be significantly cheaper than their equivalent “physical”, in fact, there are even free. For example, the complete system VoIPonCD, based entirely on Linux and open source applications, installs in minutes on a desktop PC and is packaged in a virtual appliance to run under VMWare virtualization software free.
The third advantage, not least of savings, is constituted by the versatility of VoIP systems. Advanced features such as call waiting, call to three, call forwarding, conferencing can be easily provided by the VoIP software. But the most important fact is that it is banal enrich them with new features by simply installing additional software modules or performing an upgrade of existing modules.