Polycom G7500 Reference Manual page 24

device.local.ntpServer.mode
Specifies if you want to automatically or manually configure the system to use a time server.
Auto (default) - Your system tries to automatically connect with a time server.
Manual - Set device.local.ntpServer.address.1 and optionally device.local.ntpServer.address.2.
Off - Set the current date and time in the system web interface.
device.local.timezone
Specifies the time difference between GMT and your location.
CST6CDT (default)
Etc/GMT+12
Pacific/Midway
Pacific/Honolulu
America/Adak
America/Anchorag
Pacific/Pitcairn
PST8PDT
BAJA
America/Phoenix
America/Mazatlan
MST7MDT
America/Guatemala
America/Monterrey
America/Regina
America/Lima
EST5EDT
America/Indianapolis
Canada/Atlantic
America/La//Paz
America/Caracas
America/Santiago
Canada/Newfoundland
America/Sao//Paulo
America/Cordoba
America/Godthab
America/Noronha
Atlantic/Azores
Atlantic/Cape//Verde
Etc/Greenwich
Polycom, Inc.
General System Parameters
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