Yealink SIP-T21P User Manual

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Yealink SIP-T21P firmware contains third-party software under the GNU General Public License (GPL).
Yealink uses software under the specific terms of the GPL. Please refer to the GPL for the exact terms and
conditions of the license.
The original GPL license, source code of components licensed under GPL and used in Yealink products can
be downloaded online:
http://www.yealink.com/GPLOpenSource.aspx?BaseInfoCateId=293&NewsCateId=293&CateId=293.

Yealink SIP-T21P Specifications

General

Display	132 x 64-pixel graphical LCD
Network	10/100 Mbps Ethernet
SIP Accounts	2
Wall Mountable	Yes
Audio Features	HD Voice
Protocols	SIP v1 (RFC2543), v2 (RFC3261)
Voice Codecs	G.711(A/μ), G.729AB, G.726, G.722
Phonebook	1000 entries
Call Features	Call hold, call waiting, call transfer, call forward, 3-way conferencing
Security	SRTP, TLS, 802.1x, HTTPS
Ethernet Ports	2 x RJ45 10/100 Mbps
Power Supply	Power over Ethernet (PoE) or optional power adapter
Operating Humidity	10% to 90% (non-condensing)
Languages	Supports multiple languages
PoE	Yes (802.3af)
Operating Temperature	-10°C to 50°C