... interface between PSTN and IP to achieve the conversion between FXO/FXS and VoIP SIP,meanwhile complete the media stream ... properties. With modular design of inserting board, NC-MG320 is expandable by your requirement.Function and Features:Powerful processing capabilities ·Analog Gateway NC ... , G.729 Annex A and Annex B, G.726,GSM,ARM,ILBCFax ProtocolT30, T38 and pass throughNetwork ProtocolIP,NAT,ICMP ...