Spesifikasi lengkap dari Yealink SIP-T21P E2 :

Audio Features

- HD voice: HD handset, HD speaker

- Wideband codec: AMR-WB (optional), Opus, G.722

- Narrowband codec: G.711(A/µ), G.729, G.729A, G.726, iLBC

- DTMF: In-band, Out-of-band (RFC 2833) and SIP INFO

- Full-duplex hands-free speakerphone with AEC

- VAD, CNG, AEC, PLC, AJB, AGC

Display and Indicator

- 132 x 64-pixel graphical LCD with backlight LED for call and message waiting indication

- Dual-color (red or green) illuminated LEDs for line status information

- Intuitive user interface with icons and soft keys

- Multilingual user interface

- Caller ID with name and number

- Power saving

Interface

- 2 x RJ45 10/100M Ethernet ports

- 1 x RJ9 (4P4C) handset port

- 1 x RJ9 (4P4C) headset port

Network and Security

- SIP v1 (RFC2543), v2 (RFC3261)

- Call server redundancy supported

- NAT traversal: STUN mode

- Proxy mode and peer-to-peer SIP link mode

- IP assignment: static/DHCP

- Time and date synchronization using SNTP

- UDP/TCP/DNS-SRV (RFC 3263)

- QoS: 802.1p/Q tagging (VLAN), Layer 3 ToS DSCP

- SRTP for voice

- Transport Layer Security (TLS)

- AES encryption for configuration file

- Digest authentication

- OpenVPN, IEEE802.1X, IPv6