... Platforms such as Asterisk, FreePBX, Broadsoft, Cisco call manager etc. VOIP:SIP 2.0 (RFC3261) and correlative RFCs..Full duplex hands ... domain, SIP authentication (none, basic, MD5), DNS name of server,Peer to Peer/ IP call.SIP support 2 SIP lines or only one ... Gain Setting, VAD, CNG Networking:WAN/LAN: Support Bridge and Router modelSupport basic NAT and NAPTSupport PPPoE for xDSLSupport DHCP Client ...