3Com IntelliJack NJ2000 Quick Start Manual page 3

Power is provided to the NJ2000 either through the uplink port via 802.3at or
802.3af PoE (Power over Ethernet) or locally via an optional, external 48V DC
power supply, 3CNJ1000PSL.
NOTE: PoE, or Power Over Ethernet, is a method for providing power to
equipment over an Ethernet cable, allowing a device to receive both data and
power from the same network cable. PoE power may be provided on port 1 or
port 2 of the NJ2000 if there is sufficient power available to the system. See
the section "Understand the PoE Capabilities for Port 1 and Port 2" later in this
guide for details.
NJ2000 Basics
This diagram shows the front and side views of the NJ2000. The table
describes the features.
Feature
1 4 Gigabit LAN
switch ports
with LEDs
2 Two pass-through
ports
3 Power LEDs:
DC
•
PoE
•
Description
Allows you to connect up to four devices to the network.
A green LED indicates connection status when a device is using a
particular port.
Port 1 and port 2 are also power-forwarding ports; they can be used
with any standard networking device as well as to power any device
that requires IEEE 802.3af-compatible PoE.
An additional LED indicates when the port is forwarding power to a
device connected to that port.
The pass-through ports bypass the functionality of the switch and are
directly wired to the associated pass-through ports on the rear of the
unit. Pass-through ports allow connection to a separate network
segment or connection of an analog or digital PBX telephone.
Indicate whether the NJ2000 is being powered by a local power
supply (DC) or PoE.
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