Device Interfaces
• 2 FXS ports with RJ-11 and the definition of polarity reversal
• 1 FXO port with RJ-11 and the support functions of lifeline
• 1-port WAN 10/100Base-TX with RJ-45 auto-sensing MDI / MDIX cross
• 4-port LAN 10/100Base-TX with RJ-45 auto-sensing MDI / MDIX cross

Main functions of SIP
• Individual account for each port or general account for all ports
• Determination of caller ID (Caller ID)
• Direct call IP-to-IP without SIP Proxy
• Numbering Plan (Digit Map) and Phone Book
• DNS SRV, SIP SRV
• Dialing E.164 (with an exclusion rule ENUM)
• Hot Line, Warm Line
• Setting up an interactive telephone answering (IVR)
• Message Waiting Indication (subscription)
• Visual message waiting indication (subscription)
• Music on Hold
• Outbound Proxy
• SIP INFO
• Trilateral Conference (mode Ad Hoc, media server required)
• Main function of calls:
    Blocking of anonymous calls
    Blocking and filtering of calls to the IP-address of the caller
    Call forwarding (busy, no answer, unconditional)
    Call history (status calls)
    Call Hold
    Transferring a call to a fixed number (Call park) and the removal of the call off hold (Call Retrieve) (Support Proxy)
    Transferring a call (support Proxy)
    Call Waiting
    The name of the caller and the call (FSK)
    The "Do Not Disturb» (Do not disturb)
    Blocking on Caller ID

Voice Features
• Adjustable jitter-buffer
• Echo
• Automatic detection and switching of voice / fax / data
• Auto Gain Control (AGC)
• Codecs: G.711μ/A-law, G.729A/B/AB, G.723 (6.3/5.3Kbit/s), G.726
• Comfort Noise Generation (CNG)
• DTMF detection and generation
• In-band or Out of band DTMF event
• Packet Lost Concealment (PLC)
• Supports voice / fax / modem (up to 33.6Kbit / s) over IP
• T.30 fax bypass thought G.711
• T.38 real time FAX up 14.4Kbit / s
• Voice Activity Detection (VAD)
• Detection and generation of caller ID (Caller ID): DTMF, FSK-BellCore, FSK-ETSI

Configuration / Management
• Automatic Provisioning (except options TR069/TR104)
• Web-based management user
• User interface TELNET
• Saving and restoring the configuration file through the Web-based interface
• Call history (received, missed, blocked calls)
• Call Detail Record (CDR)
• Time synchronization in accordance with NTP (the default NTP-server D-Link)
• Password protection (Web-interface and TELNET)
• Ping Test
• Reset to Factory
• SNMPv2 (except options TR069/TR104)
• Static routes and default routes
• System status
• TFTP / FTP / HTTP-client for software upgrade
• Client Support TR069/TR104 (optional)

WAN-connection
• Client Big Pond
• DHCP-client
• PPPoE Authentication via PAP / CHAP
• PPTP-client
• Static IP-address

Quality of Service (QOS)
• DiffServ (DSCP) or ToS IP Precedence tagging (WAN)
• Speed limit on the LAN port
• Speed limit on Port WAN (in increments of 64Kb / s)
• A priority queue WAN-port: first RTP
• 802.1Q and 802.1P Tagging (1 VID for VoIP-traffic, 1 VID for LAN-traffic)

NAT TRAVERSAL
• STUN-Client
• DDNS-client
• Specifying a port range for SIP and RTP
• Static route

Security
• Built-in firewall
• Filtering IP-addresses
• Filtering based on port
• Filtering based on MAC-address
• Virtual Server
• DMZ
• Protection against attacks Denial of Service (DoS)
• MD5 authentication for SIP
• Two privilege levels: Administrator and User
• VPN Pass-through with Multiple Sessions (IPSec, PPTP, L2TP)

Indicators
• Power
• Provision / Alarm
• Register
• WAN Link / Activity
• LAN Link / Activity (for 4 ports)
• Phone (for 2 ports)
• Line