It is a device capturing and controling all the signals, which are being created by the whole system, especially the made and received phone call signals. The device is mostly used for connecting regular phone system with the Internet and backwards.
It is is considered as one of the most prominent entity in the VoIP world. Company Digium has created it as a fully innovative approach to telecommunications. This company has delivered such software that enables people to configure a server and start to make calls.