Yealink Skype for Business HD IP Phones Administrator GuidexiiVLAN .............................................................................................................................................. 231LLDP ........................................................................................................................................ 232CDP ......................................................................................................................................... 236Manual Configuration for VLAN .............................................................................................. 238DHCP VLAN ............................................................................................................................ 243Quality of Service ........................................................................................................................... 246Quality of Experience ..................................................................................................................... 249IPv6 Support .................................................................................................................................. 253Configuring Audio Features ...................................................263Phone Ring Tones .......................................................................................................................... 263Private Line Ring Tone .................................................................................................................... 267Tones ............................................................................................................................................. 269Voice Mail Tone ............................................................................................................................. 276Headset Prior ................................................................................................................................. 277Dual Headset.................................................................................................................................. 279Sending Volume ............................................................................................................................. 281Audio Codecs ................................................................................................................................. 282Acoustic Clarity Technology ........................................................................................................... 290Acoustic Echo Cancellation ..................................................................................................... 290Background Noise Suppression .............................................................................................. 291Automatic Gain Control .......................................................................................................... 291Voice Activity Detection .......................................................................................................... 291Comfort Noise Generation ...................................................................................................... 293Jitter Buffer ............................................................................................................................. 294Configuring Security Features................................................299Skype for Business Feature License ................................................................................................ 299User Password ................................................................................................................................ 301Administrator Password ................................................................................................................. 302Auto-Logout Time .......................................................................................................................... 304Phone Lock .................................................................................................................................... 305Account Lock.................................................................................................................................. 308Transport Layer Security ................................................................................................................. 310Encrypting Configuration Files ....................................................................................................... 319802.1X Authentication .................................................................................................................... 324Troubleshooting .....................................................................335Troubleshooting Methods .............................................................................................................. 335Memory Information ............................................................................................................... 335Skype for Business Status ........................................................................................................ 336Viewing Log Files .................................................................................................................... 339