Voice-over-IP (VoIP) protocols:

• SIP v2 (RFC 3261)

Voice codecs:

• G.729A/B
• G.728
• G.726 (16/24/32/40 kbps)
• G.723.1 (5.3/6.3 kbps)
• G.711a-law
• G.711µ-law
• iLBC

Main features:

• Full Feature Voice/Fax-over-IP
• Ultra-Compact and Lightweight
• Universal Plug and Dial
• Extremely Cost Affordable
• 2 FXS Ports (Telephone or Fax)
• PSTN Pass-Through port

Additional features:

• Caller ID/Name display or block, Hold, Call Waiting/Flash
• Call Transfer, Call Forward
• In-band and out-of-band DTMF, Dial Plans
• Support Silence Suppression, VAD (Voice Activity Detection), CNG (Comfort Noise Generation), Line Echo Cancellation (G.168), and AGC (Automatic Gain Control)
• Support for Layer 2 (802.1Q VLAN, 802.1p) and Layer 3 QoS (ToS, DiffServ, MPLS)
• Supports dual SIP accounts via dual FXS ports