THE WHATIS.COM WORD-OF-THE-DAY August 26, 2002 Power over Ethernet ______________ TODAY'S SPONSOR: VeriSign - The Value of Trust
Secure all your Web servers now with a proven 5-part strategy. The FREE Server Security Guide shows you how to deploy the latest encryption and authentication techniques, deliver transparent protection with the strongest security without disrupting users, and more. Get your FREE Guide now: http://WhatIs.com/r/0,,5195,00.htm?FreeGuide ______________ TODAY'S WORD: Power over Ethernet See our definition with hyperlinks at http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci846792,00.html Power over Ethernet (PoE) is a technology for wired Ethernet LANs (local area networks) that allows the electrical current, necessary for the operation of each device, to be carried by the data cables rather than by power cords. This minimizes the number of wires that must be strung in order to install the network. The result is lower cost, less downtime, easier maintenance, and greater installation flexibility than with traditional wiring. For PoE to work, the electrical current must go into the data cable at the power-supply end, and come out at the device end, in such a way that the current is kept separate from the data signal so neither interferes with the other. The current enters the cable by means of a component called an injector. If the device at the other end of the cable is PoE compatible, then that device will function properly without modification. If the device is not PoE compatible, then a component called a picker or tap must be installed to remove the current from the cable. This 'picked-off' current is routed to the power jack. To minimize the possibility of damage to equipment in the event of a malfunction, the more sophisticated PoE systems employ fault protection. This feature shuts off the power supply if excessive current or a short circuit is detected. RELATED TERMS: Ethernet http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci212080,00.html LAN http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci212495,00.html current http://whatis.techtarget.com/definition/0,,sid9_gci211871,00.html ________________________ SELECTED LINKS: Jim Geier of 802.11 planet.com has written a PoE tutorial. http://www.80211-planet.com/tutorials/article/0,4000,10724_1404631,00.html Hyperlink Technologies offers PoE-compatible products. http://www.hyperlinktech.com/web/poe.html ______________________ WHATIS DISCUSSION FORUM | Challenge #13: Picking an HTML editor Les is now at the point where he needs to invest some money in a good HTML editor. He's confused about whether to invest in a high-end product that has features he's not yet ready to use, or go with something less expensive that he might outgrow. THE CHALLENGE: Recommend an HTML editor for Les to consider purchasing - OR - tell Les what HTML editor you think he should avoid (and why). http://whatis.discussions.techtarget.com/WebX?[EMAIL PROTECTED]@.1dcfae0e/113!viewtype= ______________________ QUIZ #7 | Protocols How much do you know about IT protocols? Take our quiz and find out! http://searchsystemsmanagement.techtarget.com/sDefinition/0,,sid20_gci558485,00.html ______________________________ RECENT ADDITIONS AND UPDATES [1] characteristic impedance of free space http://whatis.techtarget.com/definition/0,,sid9_gci845268,00.html [2] pixelation http://whatis.techtarget.com/definition/0,,sid9_gci844539,00.html [3] vertical line http://whatis.techtarget.com/definition/0,,sid9_gci844400,00.html [4] messaging http://searchsystemsmanagement.techtarget.com/sDefinition/0,,sid20_gci212554,00.html [5] HDCD http://whatis.techtarget.com/definition/0,,sid9_gci843768,00.html ____________________________________________________________________ ::::::::::::::::::: WHATIS.COM CONTACTS ::::::::::::::::::: LOWELL THING, Site Editor ([EMAIL PROTECTED]) ____________________________________________________________________ MARGARET ROUSE, Assistant Editor ([EMAIL PROTECTED]) ___________________________________________________________________ :::::::::::::::::::: ABOUT THIS NEWSLETTER ::::::::::::::::::::: Published by TechTarget (http://www.techtarget.com) TechTarget - The Most Targeted IT Media Copyright 2002, All Rights Reserved. If you would like to sponsor this or any TechTarget newsletter, please contact Gabrielle DeRussy at [EMAIL PROTECTED] Unsubscribe from 'Word of the Day' - Simply Reply to this Email with REMOVE within the Body or Subject > or - Go to: http://WhatIs.techtarget.com/register - Log in to edit your profile. - Click on the link to Edit email subscriptions. - Uncheck the box next to the newsletter you wish to unsubscribe from. - When finished, click "Save Changes to My Profile."
