Voice Features:

Support Bridge and Router model
Power Over Ethernet（Optional Parameters）
Support IAX2 and dual sip public server
Codec: G.711A/u, G.7231 high/low, G.729
Support Voice Gain Setting, Jitter Buffer, VAD, CNG
Call hold;
Unattended/ attended call transfer
Call waiting and per call-waiting blocking
Call forward (Always, busy, no answer, power off)
Voip speed dial
VoIP digital map
User define ring tone
E.164 dial plan and customize dial rules
Caller number/name display
Voice promote
Configurable jitter buffer size
Configurable audio frame
Call control: SIP RFC3261,H323,Tone generation and Local DTMF re-generation according with ITU-T

Network Features:

Static/Dynamic WAN-IP-Addressing 
MAC Address
TCP:Transmission Control Protocol 
DHCP:Dynamic Host Configuration Protocol
PPPoE：PPP Protocol over Ethernet
SNTP, Simple Network Time Protocol
STUN - Simple Traversal of User Datagram ...
TOS:Type of service
DNS：Domain Name Server
Support Bridge and Router model. 
RTP: Real-time Transport Protocol
RTCP:Real-time Control Protocol
Telnet: Internet's remote login protocol
HTTP:Hyper Text Transfer protocol
FTP:File Transfer protocol
TFTP:Trivial File Transfer Protocol

Management and Provisioning:

Http, telnet, keypad
Adjustable user password and super password 
URL based FTP,HTTP and TFTP auto provision 
Configure file download and upload by 
Support four settings storage, switch by keypad 
Safe mode provide reliability 
Four servers store and load by keypad 
80 entries each for missed calls, answered calls and dialed calls 
100 entries for speed dial number 
Multiply Language support