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.
Now with "NuovoVoip" by TelefonicaWeb.net ,you can call with internet telephony rates from any landline or mobile, without having to use internet, 3 g, wifi, etc
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