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.
Introduction
When shopping for the perfect PBX system, you are most likely considering IP PBX over bulky and expensive antique methods. However, the pricing schemes are both confusing and concerning, as you are unsure what you are looking at when trying to price different services out. Luckily enough, the biggest business telephone systems vendors use plans to determine prices, and these plans can be easily compared to competitors.