AP-N1-GSM4 GSM VoIP Module is a 4-Port GSM Module for GSM Call Termination Service. AP-N1-GSM4 GSM VoIP Module can be installed in our next generation AddPac GSM Gateway N1 Hardware Platform such as AP-GS3800, AP-GS3000, AP-GS2800, AP-GS2700, AP-GS2500, etc. This GSM VoIP Module supports Quad-Band(850/900/1800/1900MHz) GSM frequency, Four(4) SIM card Slots, Hot-Swap Switch Button, One(1) GSM Antenna Interface. This GSM VoIP module include 4:1 Antenna Combiner(Power Divider) internally. Also this module supports the Voice DSP for GSM call termination service based on VoIP Technology.
AP-GS3000, AP-GS2800, AP-GS2700 GSM Gateways are the-state-of-the art multichannel gsm gateway device based on voice DSP/GSM chips which allow to install 9,7,6 GSM module slots. AddPac GSM gateway is a device that can support both GSM gateway service (Digital E1/T1->GSM or Internet->GSM) and VoIP gateway service (Digital E1/T1->Internet) simultaneously. It also supports SIP, H.323 Multiple VoIP signaling protocol, various voice codec(G.711, G.726, G.729, G723.1).
GSM Gateway 
