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diff --git a/Bachelor/CCNA4/en_CCNA4_v30/ch4/4_3_1/content.html b/Bachelor/CCNA4/en_CCNA4_v30/ch4/4_3_1/content.html new file mode 100644 index 0000000..f25dc05 --- /dev/null +++ b/Bachelor/CCNA4/en_CCNA4_v30/ch4/4_3_1/content.html @@ -0,0 +1,134 @@ +<html>
+
+<head>
+<meta http-equiv="Content-Language" content="en-us">
+<meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
+
+
+
+<title>Content</title>
+<base target="_self">
+</head>
+
+<body background="../../images/bg.gif" topmargin="0" leftmargin="0" marginheight="0" marginwidth="0" onLoad="window.focus();" link="#808080" vlink="#808080" alink="#808080">
+
+<table border="0" cellpadding="0" cellspacing="0" width="100%">
+ <tr>
+ <td bgcolor="#336666" width="18" valign="top">
+ <img border="0" src="../../images/content_lines.gif" width="16" height="25">
+ <img border="0" src="../../images/transdot.gif" width="2" height="1"></td>
+ <td bgcolor="#336666"><font face="Arial" size="2" color="#FFFFFF"><b>4.</b></font><b><font face="Arial" size="2" color="#FFFFFF">3</font></b></td>
+ <td bgcolor="#336666"><img border="0" src="../../images/transdot.gif" width="10" height="1"></td>
+ <td bgcolor="#336666" width="100%"><b>
+ <font face="Arial" size="2" color="#FFFFFF">DDR Configuration</font></b></td>
+ <td width="9" bgcolor="#336666"> </td>
+ </tr>
+ <tr>
+ <td bgcolor="#669999" height="25" width="18"> </td>
+ <td bgcolor="#669999" height="25"><b>
+ <font face="Arial" size="2" color="#FFFFFF">4.3.1</font></b></td>
+ <td bgcolor="#669999"><img border="0" src="../../images/transdot.gif" width="10" height="1"></td>
+ <td bgcolor="#669999" height="25" width="100%">
+ <strong><font face="Arial" size="2" color="#FFFFFF">DDR
+ operation</font></strong></td>
+ <td bgcolor="#669999" height="25" width="9"> </td>
+ </tr></table>
+
+<table border="0" cellpadding="0" cellspacing="0" width="95%" bordercolor="#111111">
+ <tr>
+ <td width="15"></td>
+ <td><font size="2" face="Arial">
+ Dial-on-demand routing (DDR) is triggered when traffic that matches a predefined set of
+ criteria is queued to be sent out a DDR-enabled interface. The traffic
+ that causes a DDR call to be placed is referred to as interesting
+ traffic. Once the router has transmitted the interesting traffic, the
+ call is terminated.<p>The key to efficient DDR operation is in the
+ definition of interesting traffic. Interesting traffic is defined
+ with the
+ </font><font size="2" face="Courier New">
+ <b>dialer-list</b></font><font size="2" face="Arial">
+ command. Dialer lists can allow all traffic from a specific protocol
+ to bring up a DDR link, or they can query an access list to see what
+ specific types of traffic should bring up the link. Dialer lists do not filter
+ traffic on an interface. Even traffic that is not interesting will be
+ forwarded if the connection to the destination is active.</p>
+ <p>DDR is implemented in Cisco routers in the following steps:</p>
+ <ol>
+ <li>The router receives traffic, performs a routing table lookup to
+ determine if there is a route to the destination, and identifies the
+ outbound interface.
+ <img border="0" src="../../images/1.gif" align="absmiddle" width="12" height="12"></li>
+ <li>If the outbound interface is configured for DDR, the router does a
+ lookup to determine if the traffic is interesting.
+ <img border="0" src="../../images/2.gif" align="absmiddle" width="12" height="12"></li>
+ <li>The router identifies the dialing information necessary to make
+ the call using a dialer map to access the next-hop router.
+ <img border="0" src="../../images/3.gif" align="absmiddle" width="12" height="12"></li>
+ <li>The router then checks to see if the dialer map is in use. If the
+ interface is currently connected to the desired remote destination,
+ the traffic is sent. If the interface is not currently connected to
+ the remote destination, the router sends call-setup information
+ through
+ the BRI using the D channel.
+ <img border="0" src="../../images/4.gif" align="absmiddle" width="12" height="12"></li>
+ <li>After the link is enabled, the router transmits both interesting
+ and uninteresting traffic. Uninteresting traffic can include data and
+ routing updates.</li>
+ <li>The idle timer starts and runs as long as no interesting traffic
+ is seen during the idle timeout period and disconnects the call based on the idler
+ timer configuration.
+ <img border="0" src="../../images/5.gif" align="absmiddle" width="12" height="12"></li>
+ </ol>
+ <p>The idle timer setting specifies the length of time the router should
+ remain connected if no interesting traffic has been sent. Once a DDR
+ connection is established, any traffic to that destination will be
+ permitted. However, only interesting traffic resets the idle timer. </p>
+ <p>
+ <TABLE bgcolor="#B0AFAF" width="95%" border="0" cellspacing="0" cellpadding="0">
+ <TR>
+ <TD valign="top">
+ <TABLE bgcolor="#669999" width="100%" cellspacing="0" cellpadding="0" border="0">
+ <TR>
+ <TD width="5">
+ <img border="0" src="../../images/lab_toplft.gif" width="116" height="23"></TD>
+ <TD><IMG alt="" height="1" width="3" src="../../images/s.gif"></TD><TD align="right" valign="top">
+ <IMG alt="" src="../../images/corner_ur_7.gif" width="7" height="7"></TD>
+ </TR>
+ </TABLE>
+
+ <TABLE bgcolor="#B0AFAF" width="100%" cellspacing="0" cellpadding="0" border="0">
+ <TR>
+ <TD>
+ <TABLE width="100%" cellpadding="2" cellspacing="0" border="0" bordercolor="#111111">
+ <TR>
+ <TD bgcolor="#ffffff" width="15"> </TD>
+ <TD bgcolor="#ffffff"><font FACE="Arial" SIZE="2" COLOR="#000000">
+ <p><font color="#808080">
+ <img border="0" src="../../images/links_icon.gif" width="25" height="25">
+ <b>Web Links</b></font></p>
+ </font><font FACE="Arial" SIZE="2" COLOR="#808080">
+
+ <p>DDR<p>
+ <a target="_blank" href="http://www.cisco.com/en/US/tech/tk801/tk133/tech_protocol_family_home.html">
+ http://www.cisco.com/en/US/tech/tk801/ tk133/tech_protocol_family_ home.html</a></font></p>
+
+ <p>
+ <IMG alt="" height="2" width="1" src="../../images/s.gif"></p>
+ </TD>
+ </TR>
+ </TABLE>
+ </TD>
+ </TR>
+ </TABLE>
+ </TD>
+ </TR>
+ </TABLE><p>
+
+
+ </font></td>
+ </tr>
+ </table>
+
+</body>
+
+</html>
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