... product locates at the interface between PSTN and IP to achieve the conversion between FXO/FXS and VoIP SIP,meanwhile complete the ... fax, callback, second dial.Plentiful business functions ·Modification between calling number and called number; ·As a terminal, support the ... ProtocolT30, T38 and pass throughNetwork ProtocolIP,NAT,ICMP,ARP,HTTP,BOOTP,FTP,TFTP,DHCP,PPPOE,SNMP,Diff-ServEcho CancellationG. ...