⭐ 欢迎来到虫虫下载站! | 📦 资源下载 📁 资源专辑 ℹ️ 关于我们
⭐ 虫虫下载站

📄 content.htm

📁 ccna
💻 HTM
字号:
<html>

<head>
<meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
<meta name="GENERATOR" content="Microsoft FrontPage 4.0">
<meta name="ProgId" content="FrontPage.Editor.Document">
<title>Content</title>
<base target="contents">
</head>

<body>

<table border="0" width="650" cellspacing="0" cellpadding="0">
  <tr>
    <td colspan="2">
      <table border="0" width="100%" cellspacing="0" cellpadding="0">
        <tr>
          <td width="90%"><font face="Arial" size="3"><font color="#008080"><b><img border="0" src="../../images/arrow_down.gif" width="19" height="12"></b></font></font><b><font face="Arial" color="#008080" size="3">Centralized
            optical fiber cabling </font><font color="#CCCC00" size="3" face="Arial">::</font></b></td>
          <td width="10%">
            <p align="right"><font face="Arial" size="3" color="#008080"><b>44/55</b></font></td>
        </tr>
      </table>
    </td>
  </tr>
  <tr>
    <td colspan="2">
      <img border="0" src="../../images/transdot.gif" width="1" height="15"></td>
  </tr>
  <tr>
    <td><font face="Arial" size="2"><img border="0" src="../../images/transdot.gif" width="45" height="1"></font></td>
    <td><font face="Arial" size="2">Many single tenant users of high performance
      optical fiber are implementing data networks with centralized electronics
      versus distributed electronics in the building. Centralized optical fiber
      cabling is designed as an alternative to the optical cross-connection
      located in the telecommunications room when deploying recognized optical
      fiber cable in the horizontal in support of centralized electronics.</font>
      <p><font face="Arial" size="2">Centralized cabling provides connections
      from work areas to centralized cross-connects by the use of pull-through
      cables, an interconnection, or splice.</font></p>
      <p><font face="Arial" size="2">The horizontal cross-connection as
      specified in ANSI/TIA/EIA-568-B.1 and ANSI/TIA/EIA-568-B.3 provides the
      user with maximum flexibility, specifically in the deployment of
      distributed electronics or in multi-tenant buildings.</font></p>
      <p><font face="Arial" size="2">Careful planning and implementation of
      centralized optical fiber cabling will help assure that the user maintains
      adequate flexibility and manageability with the cabling network.</font></p>
      <p><font face="Arial" size="2"><b>Applicability</b></font></p>
      <p><font face="Arial" size="2">The guidelines and requirements for
      centralized optical fiber cabling networks are intended for those
      single-tenant users who desire to deploy centralized electronics rather
      than distributed electronics and want an alternative to locating the
      cross-connection in the telecommunications room.</font></p>
      <p><font face="Arial" size="2"><b>General guidelines</b></font></p>
      <p><font face="Arial" size="2">This specifies the use of either
      pull-through cables, an interconnection, or splice in the
      telecommunications room. The use of an interconnection between the
      backbone and horizontal cabling is recognized to offer increased
      flexibility, manageability, and ease to migrate to a cross-connection.</font></p>
      <p><font face="Arial" size="2"><b>Requirements</b></font></p>
      <ul>
        <li><font face="Arial" size="2">The specifications of ANSI/TIA/EIA-569-A
          shall be followed.&nbsp;</font></li>
        <li><font face="Arial" size="2">The maximum horizontal cabling distance
          is as specified in clause 4.&nbsp;</font></li>
        <li><font face="Arial" size="2">The installation shall be limited to 300
          m (984 ft) consisting of the combined length of the horizontal,
          intrabuilding backbone, and patch cords. Adhering to the 300 m (984
          ft) limitation will ensure that the recognized cabling system will
          support multi-gigabit services using centralized electronics.&nbsp;</font></li>
        <li><font face="Arial" size="2">Centralized cabling implementations
          shall be located within the same building as the work areas
          served.&nbsp;</font></li>
        <li><font face="Arial" size="2">The administration of moves and changes
          shall be performed at the centralized cross-connect.&nbsp;</font></li>
        <li><font face="Arial" size="2">The pull-through cable length shall be
          less than or equal to 90 m (295 ft).&nbsp;</font></li>
        <li><font face="Arial" size="2">Pull-through cables shall meet the same
          requirements of recognized horizontal optical fiber cable per clause 4
          of ANSI/TIA/EIA-568-B.3.&nbsp;</font></li>
        <li><font face="Arial" size="2">Centralized cabling design shall allow
          for migration (in part or in total) of the pull-through, interconnect,
          or splice implementation to a cross-connection implementation.&nbsp;</font></li>
        <li><font face="Arial" size="2">Sufficient space shall be left in the
          telecommunications room to allow for the addition of patch panels
          needed for the migration of the pull-through, interconnect, or splice
          to a cross-connection.&nbsp;</font></li>
        <li><font face="Arial" size="2">Sufficient cable slack shall exist in
          the telecommunications room to allow movement of the cables when
          migrating to a cross-connection.</font></li>
      </ul>
      <blockquote>
        <blockquote>
          <p><font face="Arial" size="1">NOTE 1 - Pull-through cables are
          continuous sheath cables that are pulled through a telecommunications
          room from the centralized cross-connect to the telecommunications
          outlet/connector.</font></p>
        </blockquote>
      </blockquote>
      <ul>
        <li><font face="Arial" size="2">Slack storage shall provide bend radius
          control so that cable and fiber bend radius limitations are not
          violated.&nbsp;</font></li>
        <li><font face="Arial" size="2">Fiber slack shall be stored in
          protective enclosures.&nbsp;</font></li>
        <li><font face="Arial" size="2">Centralized cabling design shall allow
          for the addition and removal of horizontal and intrabuilding backbone
          fibers.</font></li>
      </ul>
      <p><font face="Arial" size="2"><b>Recommendations</b></font></p>
      <ul>
        <li><font face="Arial" size="2">The addition and removal of horizontal
          links should be performed at the telecommunications room.&nbsp;</font></li>
        <li><font face="Arial" size="2">Slack may be stored as cable or
          unjacketed fiber (buffered or coated).&nbsp;</font></li>
        <li><font face="Arial" size="2">Cable slack may be stored within
          enclosures or on the walls of the telecommunications room.&nbsp;</font></li>
        <li><font face="Arial" size="2">The layout of both rack-mount and
          wall-mount termination hardware should accommodate modular growth in
          an orderly manner.</font></li>
      </ul>
      <blockquote>
        <blockquote>
          <p><font face="Arial" size="1">NOTE - Specifications on
          pull-through implementations apply equally to all media types.
          Cross-connects for different media types are required to be in the
          same location.</font></p>
        </blockquote>
      </blockquote>
      <p>&nbsp;</p>
    </td>
  </tr>
  <tr>
    <td colspan="2">
      <table border="0" width="100%" cellspacing="0" cellpadding="0">
        <tr>
          <td width="90%"><img border="0" src="../../images/arrow_up.gif" width="19" height="12"><b><font face="Arial" color="#008080" size="3">Centralized
            optical fiber cabling </font></b><font face="Arial" size="3"><b><font color="#CCCC00">::</font></b></font></td>
          <td width="10%">
            <p align="right"><font face="Arial" size="3" color="#008080"><b>44/55</b></font></td>
        </tr>
      </table>
    </td>
  </tr>
</table>

</body>

</html>

⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -