Yealink SIP-T21P User Manual

Advanced Phone Features
97
This chapter provides operating instructions for the advanced features of the SIP-T21P IP
phone. Topics include:
 Busy Lamp Field (BLF)
 Call Recording
 Hot Desking
 Intercom
 Multicast Paging
 Music on Hold
 Automatic Call Distribution (ACD)
 Messages
If you require additional information or assistance with your new phone, contact your
system administrator.
You can use BLF to monitor a specific line for status changes on the phone. For example,
you can configure a BLF key on the phone for monitoring the status of a friend’s line
(busy or idle). The BLF key LED illuminates solid green when the friend's line is in use. For
more information on BLF key LED indications, refer to LED Instructions on page 4.
You can press a BLF key to dial out the monitored phone number when the monitored
line is idle. You can receive a visual and an audio alert (if enabled), and also pick up the
call when the monitored line receives an incoming call. For more information, contact
your system administrator.
To configure a BLF key via phone user interface:
1. Press Menu->Features->DSS Keys.
2. Select the desired DSS key.
3. Press or , or the Switch soft key to select BLF from the Type field.

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