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.
Polycom SoundStation Duo is a versatile conference phone that works with both analog and IP- phone lines. This makes it a unique device - in fact, two phones in one! With this conference phone you will not need to figure out what type of line your colleagues or partners use. Polycom SoundStation Duo provides full communication through public telephone lines and IP-telephony lines.