Polycom MGC Administrator Administrator's Manual page 45

Figure 4: MCU+ 50 rear panel and dongle location
The dongle on the MGC+ 100 is located in the identical location. On both
the MGC+ 50/100, an additional bracket is installed together with the
dongle. For more information on the installation and removal of the dongle
on the MGC+ 50/100, refer to the MGC+ Hardware and Installation
Manual.
The Dongle was introduced on the MCU and MGC Manager in version 5.02.
Each dongle installed on the MCU is backward compatible with current or
previous MGC Manager versions.
Only customers with an active Polycom Premier Family Maintenance
Agreement are entitled to upgrade a version for free.
When upgrading the MGC Manager version, you are required to upgrade your
Dongle. For details of the dongle upgrade procedure, refer to the Release
Notes of the relevant version.
LAN
VGA
MOUSE
KEYBOARD
COM1
COM2
ALARMS
MGC Administrator's Guide
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