VoIP
SIP (SIP RFC3261,RFC 2543)/IAX2 support.
Hotline.
Call Forward, Call Transfer, 3-way conference calls
Call ID display
DND(Do Not Disturb),Black List,Limit List
E.164 dial plan and customized dial rules

Voice
Tone generation and Local DTMF re-generation according with ITU-T
G.711(A-law or u-law) , G.723.1(6.3kbps,5.3 kbps), G729
AGC(Auto Gain Control)
AEC(Auto Echo Cancellation)
VAD (Voice Activity Detection)
CNG(Comfort Noise Generation
G.165 compliant 96ms echo cancellation

Networking
Static/Dynamic WAN-IP-Addressing
NAT, Firewall.
VPN ( L2TP ) , Open VPN
DHCP client and server.
Support PPPoE, (used for ADSL, cable modem connecting).

Protocols
MAC Address
TCP:Transmission Control Protocol
DHCP:Dynamic Host Configuration Protocol
PPPoE:PPP Protocol over Ethernet
PoE(option)
SNTP, Simple Network Time Protocol
STUN - Simple Traversal of User Datagram ...
MD5 Message-Digest Algorithm
DNS: Domain Name Server
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
Web, telnet and keypad management.
Adjustable user password and super password
Upgrade firmware through HTTP, FTP or TFTP.
Telnet remote management.
Upload/download configration file
Auto-provisioning
Safe mode provide reliability
Phone book, maximum 500 entries.