VoIP Features Support SIP 2.0(RFC3261,RFC3262) Codec: G.711A/u, G.7231 high/low,G.729 Echo cancellation: Support G.168 Support Voice Gain Setting, Jitter Buffer,VAD,CNGcall forward, and Peer to Peer NAT transverse: support STUN client SIP support SIP domain, SIP authentication (none, basic, MD5),DNS name of server, Peer to Peer SIP support two server. Can connect to two sip server at the same time DTMF: Support SIP info, DTMF Relay,RFC2833 SIP application: support Call forward/transfer/holding/waiting Call control features: Flexible dial map, support Hotline, Empty calling No., Reject service, Black list for reject authenticated call, No disturb. Support conference and voice record Network Features WAN/LAN: Support Bridge and Router model Support basic NAT and NAPT Support PPPoE for xDSL Support DHCP Client on WAN Support DHCP Server on LAN Support DNS Relay, SNTP Client, Firewall Network tools in telnet server: Including ping, race route, telnet client