NXD-804 is a commercial SIP VOIP telephone developed by ESTONE Company himself. It is a luxe SIP VOIP telephone compatible with SIP V2, achieving full duplex hands-free call and having 128*64 graphics LCD with back light, which can display many languages. When it is disposed into H.323, NXD-804 cancooperate with Gateway and GW of most H.323. It also has perfect H.450 protocol to complete all telecom value-added services such as call transfer, call forward, call waiting, etc.. Cooperating with soft exchange system, it can totally replace traditional PBX or KEY LINE PHONE. It can also be used as LAN phone or hot-line phone. When it is disposed into SIP, NXD-804 can cooperate with most SIP system. Besides having popular g.723 and g.729, it can use low-priced GSM voice compression algorithms. This model is the first-selected one for telecom operators and the main type exported by Estone Company;
Voip Sip phone（NXD-804）Key Features：
① Support 1 line for VoIP call,SIP(RFC2543,ARFC3261)；PhoneBook with 100 groups memory；

② Network Protocol：TFTP Client/DHCP Client/ PPPoE Client；Telnet/HTTP Server； DNS Client；IP、TCP、UDP、     RTP、RTCP；IP、ICMP、ARP、RARP、SNTP；

③ Voice Quality：VAD: Voice activity detection；CNG: Comfortable noise generato；LEC: Line echo canceller；Packet     Loss Compensation；Adaptive Jitter Buffer；

④ Codec：G.711: 64k bit/s (PCM)；G.723.1: 6.3k / 5.3k bit/s；G.726: 16k / 24k / 32k / 40k bit/s (ADPCM)；G.729A      8k bit/s (CS-ACELP)；G.729B: adds VAD & CNG to G.729；

⑤ Call Function：Call Hold；Call Waiting；Call Forward；Caller ID；3-way conference

⑥ DTMF Function：In-Band DTMF；Out-of Band DTMF；SIP Info；

⑦ SIP Server：Registrar Server (three SIP account)；Outbound Proxy；

⑧ Phone Function：Volume Adjustment；Speed dial, Phone book；Flash；Speaker Phone；

⑨ IP Assignment：Static IP and DHCP；PPPoE support for ADSL or Cable modem；

⑩ Security：HTTP 1.1 basic/digest authentication for Web setup；MD5 for SIP authentication (RFC2069/ RFC 2617)；

voip Sip phone （NXD-804）Support POE Key Features:
① IEEE 802.3af compliant input interface；

② Complete input / output isolation；

③ Efficiency: 78% minimal；Over load & short circuit protection；

voip Sip phone （NXD-804）Electric Spec:
① Support POE (Power over Ethernet) ● RoHS / CE /FCC compliant；

② Ethernet Port --- 2 X 10/100MHz Ethernet Port；● AC/DC power adapter, 12V DC；DC input: 12V DC/1200A；