Yealink SIP-T52S Administrator's Guide

Configuring Advanced Features
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6. Click Confirm to accept the change.
Message Waiting Indicator (MWI)
Message Waiting Indicator (MWI) informs users of the number of messages waiting in their
mailbox without calling the mailbox. IP phones support both audio and visual MWI when
receiving new voice messages. MWI will be indicated in four ways: a warning tone, an indicator
message (including a voice mail icon) on the LCD screen, the power indicator LED slowly flashes
red and the MESSAGE key LED lights up (MESSAGE key LED is only applicable to SIP-
T29G/T27P/T27G/T23P/T23G/T21(P) E2 IP phones). For more information on power indicator
LED, refer to Power Indicator LED on page 171.
IP phones support both solicited and unsolicited MWI.
Unsolicited MWI
Unsolicited MWI is a server related feature. The IP phone sends a SUBSCRIBE message to the
server for message-summary updates. The server sends a message-summary NOTIFY within the
subscription dialog each time the MWI status changes.
Solicited MWI
For solicited MWI, you must enable MWI subscription feature on IP phones. IP phones support
subscribing the MWI messages to the account or the voice mail number.
Procedure
Configuration changes can be performed using the following methods.
Central
Provisioning
(Configuration File)
<MAC>.cfg
Configure subscribe for MWI.
Parameters:
account.X.subscribe_mwi
account.X.subscribe_mwi_expires
Configure subscribe MWI to voice mail.
Parameter:
account.X.subscribe_mwi_to_vm
Configure the voice mail number on a per-
line basis.
Parameter:
voice_mail.number.X
Configure the presentation of audio and
visual MWI.
Parameter:
account.X.display_mwi.enable

Yealink SIP-T52S Specifications

General

Touchscreen	-
Display diagonal	2.8 \
Backlight display	Yes
Display resolution	320 x 240 pixels
Lines quantity	16 lines
Phonebook capacity	1000 entries
Number of VoIP accounts	12
AC adapter input voltage	100 - 240 V
Bluetooth version	2.1+EDR
Security algorithms	802.1x RADIUS, HTTPS, MD5
Ethernet LAN interface type	Gigabit Ethernet
USB 2.0 ports quantity	1
Ethernet LAN (RJ-45) ports	2
Mounting	Desk/Wall
Handset type	Wired handset
Product type	IP Phone
Product color	Black
Voice codecs	G.722, G.723, G.723.1, G.726, OPUS, iLBC
Volume control	Digital
Operating temperature (T-T)	-10 - 40 °C
Operating relative humidity (H-H)	10 - 95 %
Cables included	LAN (RJ-45)
Number of handles included	1 pc(s)
Front camera	No
Operating system installed	Linux

Weight and Dimensions

Depth	212 mm
Width	211.6 mm
Height	166.8 mm