3Com S7902E, Configuration Manual

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PoE Configuration
The S7900E Series Ethernet Switches are distributed devices supporting Intelligent Resilient
Framework (IRF). Two S7900E series can be connected together to form a distributed IRF device. If
an S7900E series is not in any IRF, it operates as a distributed device; if the S7900E series is in an
IRF, it operates as a distributed IRF device. For introduction of IRF, refer to IRF Configuration in the
System Volume.
When configuring PoE, go to these sections for information you are interested in:
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PoE Overview
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PoE Configuration Task List
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Enabling PoE
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Detecting PDs
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Configuring the PoE Power
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Configuring PoE Power Management
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Configuring the PoE Monitoring Function
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Configuring PoE Interface through PoE Profile
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Upgrading PSE Processing Software in Service
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Displaying and Maintaining PoE
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PoE Configuration Example
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Troubleshooting PoE
PoE Overview
Introduction to PoE
Power over Ethernet (PoE) means that power sourcing equipment (PSE) supplies power to powered
devices (PDs) from Ethernet interfaces through twisted pair cables.
Advantages
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Reliable: Power is supplied in a centralized way so that it is very convenient to provide a backup
power supply.
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Easy to connect: A network terminal requires no external power supply but only an Ethernet cable.
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Standard: In compliance with IEEE 802.3af, and a globally uniform power interface is adopted.
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Promising: It can be applied to IP telephones, wireless LAN access points (APs), portable
chargers, card readers, web cameras, and data collectors.
Composition
As shown in Figure 1-1 , a PoE system consists of PoE power, PSE, power interface (PI), and PD.