Allied Telesis AT-GS950/8POE manual Power over Ethernet

Page 22

Chapter 1: Overview

Power over Ethernet

The four of the twisted pair ports on the AT-GS950/8POE switch feature Power over Ethernet (PoE) which is a mechanism for supplying power to network devices over the same twisted pair cables used to carry network traffic. This feature can simplify network installation and maintenance by allowing you to use the switch as a central power source for other network devices.

A device that receives its power over an Ethernet cable is called a powered device. Examples of such devices can be wireless access points, IP telephones, web cams, and even other Ethernet switches. A powered device connected to a port on the switch receives both network traffic and power over the same twisted pair cable.

There are several advantages that the PoE feature of the AT-GS950/ 8POE switch adds to the installation and maintenance of your network. The switch acts as the central power source for your powered devices. Adding an uninterruptible power source (UPS) to the switch, increases the protection to the switch from possible power source problems and to all of the powered devices connected to the switch. The PoE feature can increase the reliability of your network by minimizing the impact to network operations from a power failure.

PoE can also simplify the installation of your network. A frequent issue in selecting a location for a network device is making sure there is a power source nearby. This often limits equipment placement or requires the added cost and time of having additional electrical sources installed. With PoE, you can install PoE-compatible network equipment where they are needed without being concerned about whether they are near a power source.

The switch automatically determines whether or not a device connected to a port is a powered device. A powered device has a signature resistor or signature capacitor that the switch detects over the Ethernet cabling. If the resistor or capacitor is present, the switch assumes that the device is a powered device.

A port on the switch connected to a powered device can supply up to 15.4 watts of power to the device and, simultaneously, furnishing standard 10/ 100 Mbps Ethernet functionality. A PoE port that is connected to a network node that is not a powered device (that is, a device that receives its power from another power source) functions as a regular Ethernet port, without PoE. The PoE feature remains enabled on the port, but no power is delivered to the device.

22

Image 22
Contents Installation Guide Page Electrical Safety and Emissions Standards Translated Safety Statements Contents Optional Transceiver Cable Specifications Figures Figures Tables Tables Preface Product Documentation Starting a Management Session Safety Symbols Used in this Document Symbol Meaning DescriptionWhere to Find Web-based Guides Management Software Updates Contacting Allied TelesisOverview ChapterIntroduction 10/100/1000Base-T PortsPage Connector Type Speed Duplex Mode Maximum Distance 10/100/1000Base-T Twisted Pair PortsCable Type Auto-MDI/ MDI-X Port Pinouts Power over Ethernet Minimum Power Maximum Power Class Redundant Twisted Pair Ports SFP Transceiver Slots LEDs LEDSFP LEDs State Description Power Supply Power Workgroup Topology Network TopologiesCollapsed Backbone-Hub Topology Overview Installing the Hardware Reviewing Safety Precautions Page Selecting a Site for the Switch Unpacking a Switch Installing the Switch on a Desktop Installing the Switch in an Equipment Rack Ase-X Installing the Switch on a Wall Attaching a Rack-mount Bracket for Wall mounting1353 Resetting the Switch Resetting the SwitchInstalling the Hardware Cabling the Network Ports Cable Specifications Twisted Pair Cable SpecificationsOptional Transceiver Cable Specifications Cabling the Switch Connecting an RJ-45 Cable Installing Optional Transceivers Installing an SFP TransceiverRemoving the SFP Cover 1350 Powering on a Switch Cabling the Network Ports Troubleshooting Power LED is Off Twisted Pair Port Link LED is Off Port PoE LED is not Solid Green Port PoE LED is Off SFP LED is Off Transceiver is Installed but the Status is Not Present Switch Functions Intermittently Environmental Specifications Technical SpecificationsPhysical Specifications Power SpecificationsCertifications Pin Signal RJ-45 Twisted Pair Port PinoutsPinout Pair RJ-45 Style Serial Terminal Port Pinouts Appendix a Technical Specifications