LEDs for Power, Ready, Status, WAN, PC, GSM Call forward from GSM to VoIP and VoIP to GSM Dial in mode or dial out ... circuits connect to the LAN and an additional device GSM module for making GSM calls Speech quality ensured by QoS at the ... for Power, Ready, Status, WAN, PC, GSM Call forward from GSM to VoIP and VoIP to GSM Dial in mode or dial out ...