Yealink SIP-T48G Administrator's Manual page 10

Microsoft Lync Edition Administrator's Guide for SIP-T2_Series and T4_Series IP Phones
Viewing Log Files .................................................................................................................. 237
Capturing Packets ................................................................................................................ 241
Enabling Watch Dog Feature .............................................................................................. 244
Getting Information from Status Indicators ........................................................................ 245
Analyzing Configuration File ............................................................................................... 246
Troubleshooting Solutions ........................................................................................................... 247
Why is the LCD screen blank? ............................................................................................. 248
Why doesn't the IP phone get an IP address? ................................................................... 248
How do I find the basic information of the IP phone? ....................................................... 248
Why doesn't the IP phone upgrade firmware successfully? ............................................. 248
Why doesn't the IP phone display time and date correctly? ........................................... 249
Why do I get poor sound quality during a call? ................................................................ 249
Why does the IP phone use DOB format logo file instead of popular BMP , JPG and so on?
................................................................................................................................................ 249
How to increase or decrease the volume? ........................................................................ 249
What will happen if I connect both PoE cable and power adapter? Which has the higher
priority? .................................................................................................................................. 250
What is auto provisioning? .................................................................................................. 250
What is PnP? .......................................................................................................................... 250
Why doesn't the IP phone update the configuration? ...................................................... 250
How to solve the IP conflict problem? ................................................................................ 250
How to reset the IP phone to factory configurations? ....................................................... 251
How to restore the administrator password? .................................................................... 251
Why does the IP phone play the local ringback tone instead of media when placing a
long distance number without plus 0? ................................................................................ 251
What is the difference between enabling and disabling the RFC 2543 Hold feature? . 252
How can I verify the generation and firmware of the phone? ........................................ 253
Appendix ...............................................................................255
Appendix A: Glossary ................................................................................................................. 255
Appendix B: Time Zones ............................................................................................................. 257
Appendix C: Trusted Certificates ............................................................................................... 259
Appendix E: SIP (Session Initiation Protocol) ............................................................................ 260
SIP Request ............................................................................................................................ 261
SIP Header ............................................................................................................................ 261
SIP Responses ....................................................................................................................... 263
SIP Session Description Protocol (SDP) Usage .................................................................. 265
Appendix F: SIP Call Flows ......................................................................................................... 266
Successful Call Setup and Disconnect ............................................................................... 266
Unsuccessful Call Setup-Called User is Busy .................................................................. 269
Unsuccessful Call Setup-Called User Does Not Answer ................................................ 271
Successful Call Setup and Call Hold .................................................................................. 273
Successful Call Setup and Call Waiting ............................................................................. 276
Call Transfer without Consultation ...................................................................................... 281
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