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<html> <head> <meta content="en-us" http-equiv="Content-Language"> <meta content="text/html; charset=UTF-8" http-equiv="Content-Type"> <link type="text/css" rel="stylesheet" href="../../../../../css/ccna.css"> <script src="../../../../../js/framesetHelper.js" language="JavaScript"></script><script language="JavaScript"> window.scrollTo(0,0); function newPage(pageID) { alert("COMMING SOON!!\nThis feature is currently in development."); } function launchMoreInfo(oid) { dash = oid.indexOf('-'); sub1 = oid.substring(0,dash); sub2 = oid.substring(dash+1); // this is an URL base on the // system that generated the static // download of the curriculum. httpref = "http://nomar.sdf.cisco.com/servlet/org.cli.delivery.rendering.servlet.MIServlet/Static=true,LMSID=DTUI,Engine=dynamic,Theme=cnamstheme,Style=ccna,Language=en,Version=2,RootID=knet-v214aCV47051/CHAPID=null/RLOID=null/RIOID=null/"; newref = httpref + sub1 +"/"+ sub2 +"/moreinfoframeset.html"; //alert("new newref :\n" + newref); window.open(newref,'MoreInfo','toolbar=no,status=yes,menubar=no,location=no,scrollbars=yes,height=442,width=756,left=20,top=20,resizable=yes') } function launchContentResource(contentID) { top.currentSupport = 0; 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As previously mentioned, 10BASE-T terminations with RJ-45 jacks can be used for 100BASE-TX (Fast Ethernet) and 1000BASE-T (Gigabit Ethernet), hence this skill has a migration path. Also, the installed base of 10BASE-T is huge. Its popularity is still growing. This is not to diminish the importance of learning other cable terminations, especially optical fiber, but we had to choose one and that one is 10BASE-T.</p> <p>This TI relates to the Layer 1 part of CCNA Certification Exam Objective #1.</p> </span></td> </tr> </table> </td> </tr> </table> </td> </tr> </table><p>This curriculum introduces three LAN technologies: <i>Ethernet</i>, <i>Token Ring</i>, and <i>FDDI</i>. All three have a wide variety of Layer 1 components and devices. The focus of this chapter will be Ethernet 10BASE-T technologies.</p><p>When it was developed, Ethernet was designed to fill the middle ground between long distance, low-speed networks, and specialized computer room networks that carried data at high speeds for very limited distances. Ethernet is well-suited to applications in which a local communication medium must carry sporadic, occasionally heavy, traffic at high-peak data rates.</p><p>The Ethernet 10BASE-T technologies carry Ethernet frames on inexpensive twisted pair wiring. Students will study four components and three devices that are related to these technologies. The first four components are <i>passive</i>, meaning they require no energy to operate. They are: </p><ul type="disc"><li>Patch panels</li><li>Plugs</li><li>Cabling</li><li>Jacks</li></ul><p>The last three are <i>active</i>. They require energy to do their jobs. They are:</p><ul type="disc"><li>Transceivers</li><li>Repeaters</li><li>Hubs</li></ul><p>For more information on other Ethernet, Token Ring, and FDDI components and devices, go to the website.</p><table cellpadding="0" cellspacing="4" width="63%" border="0" xmlns:java="http://xml.apache.org/xslt/java"> <tr> <td valign="middle" width="8%"><img height="23" width="23" src="../../../../../images/ccna/common/icon2.gif"></td><td valign="middle" width="92%"><span class="cstitle">Web Links</span></td> </tr> <tr> <td valign="middle" width="8%"> </td><td valign="middle" width="92%"><span class="smtext"><a target="_blank" href="http://www.blackbox.com/">Blackbox Network Services</a></span></td> </tr> </table></td> </tr> </table> </td> </tr></table> <p> </p> <table width="100%" cellspacing="0" cellpadding="2" border="0" valign="bottom"> <tr> <td></td> </tr> </table> </body></html>⌨️ 快捷键说明
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