Yealink SIP-T52S Administrator's Guide

Appendix
1081
Step
Action
Description
 User A is identified as the call session
initiator in the From field.
 A unique numeric identifier is assigned
to the call and is inserted in the Call-ID
field.
 The transaction number within a single
call leg is identified in the CSeq field.
 The media capability User A is ready to
receive is specified.
 The port on which User B is prepared to
receive the RTP data is specified.
F2
INVITE—Proxy Server to User B
The proxy server maps the SIP URI in the
To field to User B. The proxy server sends
the INVITE message to User B.
F3
180 Ringing—User B to Proxy
Server
User B sends a SIP 180 Ringing response
to the proxy server. The 180 Ringing
response indicates that the user is being
alerted.
F4
180 Ringing—Proxy Server to
User A
The proxy server forwards the 180 Ringing
response to User A. User A hears the ring-
back tone indicating that User B is being
alerted.
F5
200 OK—User B to Proxy Server
User B sends a SIP 200 OK response to the
proxy server. The 200 OK response
notifies User A that the connection has
been made.
F6
200 OK—Proxy Server to User A
The proxy server forwards the 200 OK
message to User A. The 200 OK response
notifies User A that the connection has
been made.
F7
ACK—User A to Proxy Server
User A sends a SIP ACK to the proxy
server, The ACK confirms that User A has
received the 200 OK response. The call
session is now active.
F8
ACK—Proxy Server to User B
The proxy server sends the SIP ACK to
User B. The ACK confirms that the proxy
server has received the 200 OK response.
The call session is now active.

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