Allied Telesis IE200 Series - Manual (Page 26)

Chapter 1: Overview
AT-IE200 Series Installation Guide 26
Power Over Ethernet
The AT-IE200-6GP and AT-IE200-6FP switches feature Power over Ethernet (PoE) on the 10/100Base-T or
10/100/1000Base-T ports. PoE is used to supply power to network devices over the same twisted pair cables
that carry the network traffic.
One of the advantages of PoE is that it makes it easier to install a network. The placement of network devices
is often limited by whether there are power sources nearby. This often limits equipment placement or
requires the added time and cost of having additional electrical sources installed. But with PoE, you can install
PoE-compatible devices wherever they are needed without having to worry about whether there are power
sources nearby.
A device that provides PoE to other network devices is referred to as power sourcing equipment (PSE). The
switches act as PSE units by adding DC power to the network cable, thus functioning as a central power
source for other network devices.
Devices that receive their power from a PSE are called powered devices (PD). Examples include wireless access
points, IP telephones, webcams, and even other Ethernet switches.
The switch automatically determines whether or not a device connected to a port is a powered device. Ports
that are connected to network nodes that are not powered devices (that is, devices that receive their power
from another power source) function as regular Ethernet ports, without PoE. The PoE feature remains
activated on the ports but no power is delivered to the devices.
PoE Standards
The AT-IE200-6GP and AT-IE200-6FP switches support these PoE standards:
 PoE (IEEE 802.3af): This standard provides up to 15.4 watts at the switch port to
support powered devices that require up to 12.95 watts.
 PoE+ (IEEE 802.3at): This standard provides up to 30.0 watts at the switch port to
support powered devices that require up to 25.5 watts.
Powered Device Classes
Powered devices are grouped into the five classes listed in Table 3. The classes are based on the amount of
power the devices require. The switches support all five classes.
Table 3: IEEE Powered Device Classes
Class
Maximum Power Output
from a Switch Port
PD Power Range
0 15.4W 0.44W to 12.95W
1 4.0W 0.44W to 3.84W
2 7.0W 3.84W to 6.49W