3Com Switch 8800 Advanced Software V5 Configuration Guide

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POE CONFIGURATION
PoE Overview
Introduction to PoE Power over Ethernet (PoE) means that power sourcing equipment (PSE) supplies
power to powered devices (PDs) such as IP telephone, wireless LAN access point,
and web camera from Ethernet ports through twisted pair cables.
A PoE device can provide 48 VDC power to its PDs and provide power supply
monitoring and PD priority management.
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Among the interface cards for Switch 8800 Family, the 3C17528 and 3C17532
interface cards support PoE.
Advantages
■ Reliable: Power is supplied in a centralized way so that it is very convenient to
provide a backup power supply.
■ Easy to connect: A network terminal requires only one Ethernet cable, but no
external power supply.
■ Standard: In compliance with IEEE 802.3af, a globally uniform power interface
is adopted.
■ Promising: It can be applied to IP telephones, wireless LAN access points,
portable chargers, card readers, web cameras, and data collectors.
Composition
A PoE system consists of PoE power, PSE, and PD.
■ PoE power
The whole PoE system is powered by the PoE power, which includes external PoE
power and internal PoE power.
■ PSE
PSE is an entity used to manage PoE for ports on a card or subcard. The PSEs on
cards/subcards manage the PoE interfaces on their own cards/subcards
independently. Through the PoE interface cables, a PSE detects PDs, classifies
them, supplies power to them, and stops supplying power to a PD when it detects
that the PD is removed.
An Ethernet interface with the PoE capability is called a PoE interface. Currently, a
PoE interface can be an FE (Fast Ethernet) or GE (Gigabit Ethernet) interface.
■ PD