Physical

• Dimensions (H×W×D): 3.9 x 3.9 x 1 in. (100 × 100 × 28 mm) 
• Weight: 4.7 oz (132.1 g)
• Interface: Two RJ11 FXS ports, one 10/100 Mbps RJ-45 Ethernet port, power button: reset and PRT 
• LED indicators: Power, Network, Phone 1, Phone 2, PRT 
• Wall mountable

Subscriber Line Interface Circuit (SLIC)

• Ring voltage: 40 to 90 Vpk configurable 
• Ring frequency accuracy: 1% 
• Ring waveform: Trapezoidal or sinusoidal 
• Maximum ringer load: 3 Ringer Equivalence Numbers (RENs) 
• On-hook voltage (tip and ring): -46 to -56V 
• Off-hook current: 25mA +/-10% 
• Terminating impedance: 600 ohm resistive, 900 ohm resistive, or 220 ohm + 820 ohm 120 nF complex impedance 
• Frequency response: 300 to 3400 Hz 
• Return loss (600 ohm, 300 to 3400 Hz): up to 26 dB 
• Idle channel noise: <-65 dBm 0p 
• Longitudinal balance: 58 dB (typical) 
• Voice quality Mean Opinion Score (MOS): >4.0 
• Voice quality jitter: <150ms

Networking

• MAC address 
• IPv4 only 
• IPv6 only 
• IPv4/IPv6 dual stack 
• Session Initiation Protocol (SIP) 
• Transmission Control Protocol (TCP) 
• User Datagram Protocol (UDP) 
• Real Time Protocol (RTP) 
• Real Time Control Protocol (RTCP) 
• HTTP 
• Secure HTTP (HTTPS) 
• Trivial File Transfer Protocol (TFTP) 
• Address Resolution Protocol (ARP) 
• DNS A and AAAA records 
• Dynamic Host Configuration Protocol (DHCP) client 
• Internet Control Message Protocol (ICMP) 
• Simple Network Time Protocol (SNTP) 
• Cisco Discovery Protocol (CDP) 
• Link Layer Discovery Protocol (LLDP)

Quality of Service (QoS)

• IEEE 802.1p/Q (QoS and VLAN tagging) 
• Differentiated Services (DiffServ) / Type of Service (ToS)

Telephony

• Call forwarding: No answer, busy, and all 
• Call hold and resume 
• Caller ID generation (name and number): Bellcore, BT, and European Telecommunications Standards Institute (ETSI) 
• Caller ID with name and number 
• Call pickup and group pickup 
• Call transfer 
• Call waiting 
• Conference 
• Configurable ring frequency 
• Country-specific tones and cadences 
• Disconnect tone 
• Distinctive ringing: Calling and called number 
• Forced Authorization Code (FAC)/Client Matter Code (CMC) 
• Failover and fall back 
• Flash hook timer 
• Hook flash event signaling 
• Hotline and warm line calling 
• Message Waiting Indicator (MWI) tones 
• Music on hold 
• Off-hook warning tone 
• Polarity control 
• Redial 
• Share lines 
• Speed dial 
• Tip and ring voltage adjustment setting 
• Visual Messaging Waiting Indicator (VMWI) using Frequency Shift Keying (FSK)

Audio

• Codec: G.711 a-law, G.711 μ-law, G.729a, G.729ab 
• Full duplex audio 
• Echo cancellation 
• Voice activity detection 
• Silence suppression 
• Comfort noise generation 
• Adaptive jitter buffer 
• Frame loss concealment 
• Adjustable audio frames per packet 
• Call progress tone generation 
• Impedance and gain adjustment 
• Dynamic audio payload

Fax and modem

• Real-time fax over IP via T.38 fax relay (Group 3) 
• Fax pass-through via G.711 (Group 3) 
• Fax tone detection and pass-through 
• Auto negotiation on transmission rate

Provisioning and management

• Central configuration 
• Interactive Voice Response (IVR) 
• Automated provisioning and upgrading via HTTP and TFTP 
• SSH access 
• Nonintrusive, in-service upgrades 
• Report generation and event logging 
• Dedicate PRT button 
• Support RTP statistics 
• Syslog (multilevel granularity)
• Dual image

Security

• System reset to factory default 
• Password-protected administrator access authority 
• Provisioning, configuration, and authentication 
• HTTPS with factory-installed client certificate 
• Advanced Encryption Standard (AES) encryption 
• SIP over Transport Layer Security (TLS) 1.1 and 1.2 
• Secure (encrypted) calling using Secure RTP (sRTP) 
• Encrypted TFTP configuration files 
• Image authentication 
• Secure boot 
• Secure Shell (SSH)

Power

• DC input voltage: 5V DC at 2.0A maximum 
• Power consumption: 5W 
• Switching type (100 to 240V) automatic 
• Power adapter: 100 to 240V and 50 to 60 Hz (26 to 34 VA) AC input, with 6-ft (1.8-m) cord

Reliability

• Mean Time Between Failures (MTBF): 300,000 hours 
• Operating temperature: 32° to 104°F (0° to 40°C) 
• Nonoperating temperature: 14° to 140°F (-10° to 60°C) 
• Humidity: Operating 10% to 90%, noncondensing; nonoperating 10% to 95%, noncondensing