Enterasys Networks 7G4285-49, 7G4205-72 manual About PoE Power over Ethernet, Overview

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C

About PoE (Power over Ethernet)

This appendix provides an overview of Power over Ethernet Technology and how it is implemented in relation to the 7G4285‐49 and 7G4205‐72 DFE modules.

Overview

Power over Ethernet (PoE) refers to the ability to provide operational power through the same Ethernet cabling to a PD (powered device) connected to a data network. Modern Ethernet implementations employ differential signals over twisted pair cables. This requires a minimum of two twisted pairs for a single physical link. Both ends of the cable are isolated with transformers blocking any DC or common mode voltage on the signal pair. PoE exploits this fact by using two twisted pairs as the two conductors to supply a direct current. One pair carries the power supply current and the other pair provides a path for the return current. While several proprietary legacy implementations of PoE have been deployed by LAN equipment vendors, in 2003 the IEEE published the IEEE 802.3af‐2003 specification, which is part of the 802.3 suite of standards.

The 7G4285‐49 and 7G4205‐72 are fully compliant with the IEEE 802.3af standard. They support the standard resistor based detection method, as well as AC disconnect capability. The 7G4285‐49 and 7G4205‐72 are also capable of supplying the maximum specified current to all ports simultaneously.

Each PD has a PDC (Powered Device Classification) that is transmitted to the DFE module for power management purposes. Table C‐1 lists the classifications and the associated power ranges.

Table C-1 Powered Device Classifications

Class	Usage	PD Maximum Power Range Usage

0	Default	0.44 to 12.95 Watts

1	Optional	0.44 to 3.84 Watts

2	Optional	3.84 to 6.49 Watts

3	Optional	6.49 to 12.95 Watts

4	Not Allowed	Reserved for Future Use

DFE-Platinum Series Hardware Installation Guide C-1

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Contents Enterasys Matrix Page Page Class a ITE Notice Clase A. Aviso de ITE Product SafetyFederal Communications Commission FCC Notice Industry Canada NoticeHazardous Substances Electromagnetic Compatibility EMCCompatibilidad Electromágnetica EMC Elektro- magnetische Kompatibilität EMCSupplement to Product Instructions Bsmi EMC Statement Taiwan Vcci NoticeDeclaration of Conformity Safety Information Class 1 Laser TransceiversEnterasys NETWORKS, INC. Firmware License Agreement Viii Page Page Contents Appendix a Specifications Figures Xiv Who Should Use This Guide About This GuideRelated Documents How to Use This GuideFor Refer to Following conventions are used in this guide Conventions Used in This GuideSupport@enterasys.com Getting HelpOverview of DFE-Platinum Series Module Capabilities Introduction7G4285-49 DFE Module and Interface Options7G4285-49 DFE-Platinum Module 7G4205-72 7G4205-72 DFE-Platinum Module Management Switch Configuration Using WebViewNetwork Expansion Module NEM ConnectivitySecure Networks Policy Support Switch Configuration Using CLI CommandsStandards Compatibility Lanview Diagnostic LEDs Network Requirements 10BASE-T Network Link Aggregation1000BASE-T Network 100BASE-TX Network1000BASE-T Network Network Requirements Installation Unpacking the DFE Module Installation Site RequirementContents of DFE Module Carton Quantity Required ToolsDFE Module Placement and Installation Rules Installing an Optional Network Expansion Module NEMMatrix E7 Chassis Module Placement Example 2 -1,B Example 1 -1,AExample 3 -1, C Example 5 -1, E Example 4 -1,DExample 6 -1, F Preparing to Install into a Chassis Installing the DFE Modules into a Matrix E7 or N7 Chassis Preparing to Install into a Chassis Preparing to Install into a Chassis Installing the DFE Modules into a Matrix N3 or N5 Chassis Card guides Connecting to the Network Connecting 48 Vdc Power for PoE OperationMaking the UTP Connections Connecting UTP Cables to DFE ModulesConnecting a Twisted Pair Segment with RJ45 Connector RX+ TX+ TX1+ 1 RX1- 2 TX2+ 3 TX3+ 4 RX3- 5 RX2- 6 TX4+ 7 RX4 Verifying PoE Port Status What Is Needed Connecting to COM Port for Local ManagementConnecting to an IBM PC or Compatible Device Parameter Setting Connecting to a VT Series Terminal10 Connecting a VT Series Terminal Connecting to a Modem11 Connecting to a Modem COM Port Adapter Wiring and Signal Diagram RJ45 Adapter Wiring and Signal AssignmentsRJ45 DB25 Modem Port Adapter Wiring and Signal Diagram Completing the Installation of a New System Completing the InstallationFirst-Time Log-In Using a Console Port Connection 12 Matrix DFE Startup Screen Example N7 Chassis Enter Logging in with an Administratively-Configured User AccountUsing Lanview TroubleshootingAbout the Management Mgmt LED Lanview LEDs on 7G4285-49 Viewing Receive/Transmit Activity on 7G4285-49Lanview LEDs on 7G4205-72 Viewing Receive/Transmit Activity on 7G4205-72Viewing the PoE Port Status Color State Recommended Action Lanview LEDsLED RX/TX Platinum Series Configuration Guide for Troubleshooting ChecklistProblem Possible Cause Recommended Action Troubleshooting ChecklistOverview of DFE Module Shutdown Procedure OFFLINE/RESET Switch Recommended Shutdown Procedure Using OFFLINE/RESET SwitchLast Resort Shutdown Procedure Using OFFLINE/RESET Switch Specifications Physical DFE Module SpecificationsTable A-1 7G4285-49 Specifications Processors/MemoryTable A-2 7G4205-72 Specifications Table A-4 Compliance Standards Regulatory Compliance Table A-3 COM Port Pin Assignments Signal Name Input/OutputCOM Port Pinout Assignments Regulatory ComplianceMode Switch Settings and Option Installations Setting the Mode Switches Memory Locations and Replacement Procedures Dram Simm Dimm Removing the Safety Cover Gaining Access to Memory ModulesFigure B-3 Removing the Safety Cover Figure B-4 Removing the Optional Network Expansion Module Dram Simm Replacement ProcedureGaining Access to Memory Modules Removing the Dimm Figure B-6 Installing the Dimm Dimm Replacement ProcedureFigure B-7 Removing the Existing Dimm Figure B-8 Installing the Dimm Installing the Network Expansion Module NEMFigure B-9 Installing the Network Expansion Module NEM Reinstalling the Safety Cover Figure B-10 Installing the Safety Cover Page Overview About PoE Power over EthernetProprietary PD Detection Table C-2 PoE Status LED Indications PoE Port Status PoE Port Status LEDsOverview About PoE Power over Ethernet Numerics IndexNEM B-12 installing