... built-in, one for internet, one for PCPOE (Power over Ethernet) FunctionNetwork ProtocolSIP v1(RFC2543), v2(RFC3261)IP/TCP/UDP/RTP ... ClientNATSIP ServerRegistrar Server: 5 SIP user accountsOutbound Proxy modePower over Ethernet (optional)CodecG.711G.723.1/iLBCG.726G.729AG.729B adds ... Input: 100-240VAC, Output Power: DC-5.5V,1AWAN RJ45,10/100M portLAN/PC RJ45,10/100M port