Beijing Reuters Katherine Technologies Co., Ltd., established in 2001 ,, was founded 14 years has focused on the development and construction of the call center system. Should our customers, is the creation of this shop, hoping to provide our customers a more convenient service. Enterprise-class IP Phone SIP-T21P Yealink SIP-T21P graphical LCD screen, to 132x64 resolution, support Chinese display; provide two SIP accounts; providing privacy and protection; phone comes with 3-way voice conference calls, with a wealth of features ; support headset interface, PoE power supply; supports PnP automatic deployment; compatible with mainstream IP-PBX; easy to install and to use, easy to manage, improve office efficiency;. fully meet the SME, call centers, government and industry users demand characteristics> Support 2 line, hotline, emergency numbers outgoing> Support call hold, call waiting, call forwarding, call back> Call Transfer (busy turn, half turn consulting, consulting turn)> Caller ID, redial, mute, DND DND,> autoresponder, tripartite voice conference calls> Speed ??Dial, SMS, voicemail> message alert lights, the national tone, volume control> IP Direct account no way> ringtone selection, import, delete> phonebook search / Export / Import ( 1000)> blacklist, call history (100)> configurable user interface> languages ??and input methods> Phone buttons can be custom programmed> call center headset mode setting feature supports two phone lines, hotlines, emergency numbers exhaled support call hold, call waiting, call forwarding, call-back call forwarding (busy turn, half turn consulting, advisory turn) Caller ID, redial, mute, DND DND, automatic answering, voice tripartite conference call speed dial, SMS, voice mail message alert lights, national tone, volume control, no account support IP dial tones way to select, import, delete phonebook search / Export / Import (1000) blacklist, call history (100) can be configured to a variety of user interface Language and input buttons can be custom programmed telephone call center headset mode setting advanced features BLF / BLA, BLF list, DND & call transfer state synchronization intercom (Intercom), Paging Pickup (Call pickup), call waiting tone berth, Distinctive Ringing call recording, answering the call to complete the group, the group Pickup anonymous calls, anonymous call reject web conferencing dialing rules, immediately exhale IP-PBX functionality BLF / BLA, BLF list, DND & call transfer state synchronization interphone (Intercom), Paging Pickup (Call pickup), call waiting tone parked, distinctive ringing call recording, answering the call to complete the group, the group Pickup anonymous calls, anonymous call reject web conferencing dialing rules, immediately exhale audio Characteristics of broadband coding: G.722 narrowband coding: G.711μ / A, G723.1, G726, G.729AB support VAD, CNG, AEC, PLC, AJB, AGC and other full-duplex speakerphone audio processing with automatic echo cancellation Network Features Support SIP v1 (RFC2543), V2 (RFC3261) protocol SIP connection mode: proxy mode, peer mode supports direct connection IPv6, LLDP support DNS SRV (RFC3263) mode supports multi-server support STUN penetrate the network supports three DTMF Mode: band (In-band), RFC2833, SIP INFO supports three IP Access: Static IP / DHCP / PPPoE dialup network port bridge and router mode built-in support HTTP / HTTPS Web server configuration management support for Telnet, built-in DNS / TFTP / FTP client supports NAT / DHCP server configuration management support for FTP / TFTP / HTTP / HTTPS / PnP mode automatically update supports three configuration modes: Web, phone, and automatic configuration support for SNMP V1 / 2, support for TR069 / SNMP custom, capture and system log export factory configuration file security protocol OpenVPN, support for 802.1x, VLAN QoS (802.1pq) supports TLS (Transport Layer Security) protocol support HTTPS protocol (client / server) protocol support SRTP (RFC3711 ) support mechanism to verify MD5 / MD5-SESS supports AES encryption protocol support phone lock, support administrator / user classification model the physical properties of 132x64 pixel graphical LCD external totaling 31 buttons, 2 line keys (programmable) 4 LED lights : a power lamp, two line lights, a voice message light an RJ-9 (4P4C) handle interfaces 1 RJ-9 (4P4C) headset connector 2 RJ-45 10 / 100M Ethernet port can be wall-mounted Power Adapter: AC 100-240V input, DC 5V / 600mA output support Power over Ethernet (PoE): IEEE 802.3af class 2 power: 1.4-2.6W, NW: 0.81KG bare size: 209mmx188mmx150mmx41mm Operating Humidity: 10-95 % Temperature: -10 ~ 50 ° C