Yealink SIP-T21P User Manual

Basic Call Features
75
for example “2/3”, indicating that this is the second call out of three calls.
You can use DND to reject incoming calls automatically on the phone. Callers will
receive a busy message.
You can enable/disable DND for the phone system, or you can customize DND for each
or all accounts. Two DND modes:
 Phone (default): DND is effective for the phone system.
 Custom: DND can be configured for each or all accounts.
You can receive incoming calls from authorized numbers when DND is enabled.
To configure the DND mode via web user interface:
1. Click on Features->Forward & DND.
2. In the DND block, mark the desired radio box in the Mode field.
3. Click Confirm to accept the change.
Note
DND mode is configurable via web user interface only.

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