Yealink SIP-T4X Administration Manual page 14

How to reboot IP phone remotely? ..................................................................................... 238
How to increase or decrease the volume? ........................................................................ 238
What will happen if I connect both PoE cable and power adapter? Which has the higher
priority? .................................................................................................................................. 239
What is auto provisioning? .................................................................................................. 239
What is PnP? .......................................................................................................................... 239
Why doesn't the IP phone update the configuration? ...................................................... 239
What do "on code" and "off code" mean? ....................................................................... 239
How to solve the IP conflict problem? ................................................................................ 240
How to reset your phone to factory configurations? ......................................................... 240
How to restore the administrator password? .................................................................... 241
Appendix ...............................................................................243
Appendix A: Glossary ................................................................................................................. 243
Appendix B: Time Zones ............................................................................................................. 245
Appendix C: Configuration Parameters .................................................................................... 248
Setting Parameters in Configuration Files .......................................................................... 248
Basic and Advanced Feature Parameters ......................................................................... 248
Audio Feature Parameters ................................................................................................... 359
Upgrading Firmware ........................................................................................................... 371
Resource Files ....................................................................................................................... 374
Troubleshooting .................................................................................................................... 379
Configuring DSS Key ............................................................................................................ 381
Appendix D: SIP (Session Initiation Protocol) ............................................................................ 396
RFC and Internet Draft Support .......................................................................................... 396
SIP Request ............................................................................................................................ 399
SIP Header ............................................................................................................................ 400
SIP Responses ....................................................................................................................... 401
SIP Session Description Protocol (SDP) Usage .................................................................. 403
Appendix E: SIP Call Flows ......................................................................................................... 404
Successful Call Setup and Disconnect ............................................................................... 405
Unsuccessful Call Setup-Called User is Busy .................................................................. 407
Unsuccessful Call Setup-Called User Does Not Answer ................................................ 410
Successful Call Setup and Call Hold .................................................................................. 412
Successful Call Setup and Call Waiting ............................................................................. 414
Call Transfer without Consultation ...................................................................................... 419
Call Transfer with Consultation ............................................................................................ 423
Always Call Forward ............................................................................................................ 428
Busy Call Forward ................................................................................................................ 432
No Answer Call Forward ..................................................................................................... 435
Call Conference .................................................................................................................... 438
Appendix F: Sample Configuration File .................................................................................... 443
Index ......................................................................................449
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