... . IAD04(W:4S) the 4port VOIP gateway includes 4 FXS ports gateway,and with 1 WAN and 1-4 ... VoIP protocol: H323 v2,H323 v4,SIP,compliance ITEF RFC3261 standard network protocol: IP,TCP,RTP,RTCP,ICMP, ... to phone calling or fax through internet and trunking gateway l support FXS and FXO 1:1 binding ... . l Compatible l interoperatability l Compatiable with voice gateway,IAD,AG,MG devices with H.323 and SIP ...