Polycom DOC2232A - Manual (Page 16)

MGC-25 Getting Started Guide
2-2
Rear Panel
The MGC-25 rear panel includes interfaces for two PRI connections, two
LAN connections, one Control LAN connection, a power cable, power
switch, cooling fan and interfaces for Polycom Support personnel.
Dongle
The Polycom MGC-25 Dongle is a hardware key that is installed in the
parallel port on the rear panel. This device contains configuration and
licensing data that is necessary for your system to function.
Never remove the dongle unless instructed by authorized support personnel.
Do not remove or damage the dongle label.