1. Standard sip 2.0 terminal product, powerful applicability, and best for global popularizing; 2. Support sip 2.0, tcp/udp/IP, rtp/rtcp, icmp, arp/rarp, ntp, pppoe, tftp, HTTP, etc; 3. Support g.711 (alaw and u-law), g.723.1 (5.3k/6.3k), g.723 (40k/32k/24k/16k), g.728, g.729a/b, ilbc; 4. The powerful dsp digital audio processor to keeping a wonderful audio-quality; 5. Inside dns, route, nat, dmz, the gateway and dhcp (the client end and the server end). 6. Advanced shaking control, and the technology of hiding the lost massage 7. Support incoming call on show, restricting, and holding, disconnection, call transfer, call divert, dialing project, etc. Support conference by sides 8. Supports vad, cng, agc, the echo eliminates (g.168) and the static sound suppression; 9. Support layer 2 (802.1q vlan,802.1p) and layer 3 (qos,, tos diffserv, mpls) 10. Powerful long-distance tftp or HTTP manages; 11. To dispose through the browser or the voice hint; 12. Nat automatic penetration; 13. Support passing through and t.38 fax; 14. Good for the environment, according to the international electromagnetism radicalizations standard; 15. Select high quality material, original electrocircuit design, and no electric current noise, work steadily; 16. Porcelain and legerity design, let you feel the full-bodied appetency of the product besides expediency schlepping