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.
AddPac AP-GS1001C is an entry level VoIP-GSM gateway, designed to work with one GSM channel. The device allows you to connect to the VoIP-telephony, analog lines and GSM networks. At the same time, users are able to transfer traffic in any direction lines are connected to: VoIP to GSM; an analog network to GSM; from analog to VoIP network.