Supports SIP2.0 (RFC3261), TCP/UDP/IP, RTP/RTCP, HTTP, ICMP, ARP/RARP, DNS, DHCP, NTP, STUN, and TFTP etc;    
Use the DSP CNOS chip to keep a wonderful audio-quality,Jitter control and packet loss concealment technology;
Support kinds of voice codes, including G.711 (a-law and u-law) G.723.1 (5.3K/6.3K) G.726 (40K/32K/24K/16K), G.729A/B, and iLBC;
Supports incoming call on show, restricting, and holding, disconnection, call transfer, call divert, DTMF, dialing plan, etc;
Supports conference call;
Supports NAT auto- penetrating, no need to modify the setting of the NAT;
Supports passing through and T38 fax, voice restrain and jerquers, CNG, echo restrains (G.168), AGC;
Supports remote upgrade and upgrade configuration function;
Supports layer 2(802.1Q VLAN, 802.1p) and layer 3 (QoS, DiffServ, ToS);
Supports SIP encrypts mode, avoid force-out;
Supports upgrading encrypts configuration files by HTTP;
Supports configuration files by inside IVR equipment, Web browser, HTTP Center Server;
Supports the volume adjustment of gateway;

Technical parameter