74 lines
4.2 KiB
HTML
74 lines
4.2 KiB
HTML
<?xml version="1.0" encoding="UTF-8"?>
|
|
<!DOCTYPE html
|
|
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
|
<html lang="en-us" xml:lang="en-us">
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
|
<meta name="security" content="public" />
|
|
<meta name="Robots" content="index,follow" />
|
|
<meta http-equiv="PICS-Label" content='(PICS-1.1 "http://www.icra.org/ratingsv02.html" l gen true r (cz 1 lz 1 nz 1 oz 1 vz 1) "http://www.rsac.org/ratingsv01.html" l gen true r (n 0 s 0 v 0 l 0) "http://www.classify.org/safesurf/" l gen true r (SS~~000 1))' />
|
|
<meta name="DC.Type" content="concept" />
|
|
<meta name="DC.Title" content="Secure the DHCP server" />
|
|
<meta name="abstract" content="This article provides recommendations for securing the DHCP server." />
|
|
<meta name="description" content="This article provides recommendations for securing the DHCP server." />
|
|
<meta name="DC.Relation" scheme="URI" content="rzamvtcpdhcp.htm" />
|
|
<meta name="copyright" content="(C) Copyright IBM Corporation 2006" />
|
|
<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 2006" />
|
|
<meta name="DC.Format" content="XHTML" />
|
|
<meta name="DC.Identifier" content="tcpsecdhcp" />
|
|
<meta name="DC.Language" content="en-us" />
|
|
<!-- All rights reserved. Licensed Materials Property of IBM -->
|
|
<!-- US Government Users Restricted Rights -->
|
|
<!-- Use, duplication or disclosure restricted by -->
|
|
<!-- GSA ADP Schedule Contract with IBM Corp. -->
|
|
<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
|
|
<link rel="stylesheet" type="text/css" href="./ic.css" />
|
|
<title>Secure the DHCP server</title>
|
|
</head>
|
|
<body id="tcpsecdhcp"><a name="tcpsecdhcp"><!-- --></a>
|
|
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
|
|
<h1 class="topictitle1">Secure the DHCP server</h1>
|
|
<div><p>This article provides recommendations for securing the DHCP server.</p>
|
|
<p>Following are security considerations when you choose to run DHCP on your
|
|
system:</p>
|
|
<ul><li>Restrict the number of users who have authority to administer DHCP. Administering
|
|
DHCP requires the following authority:<ul><li>*IOSYSCFG special authority</li>
|
|
<li>*RW authority to the following files:<pre>/QIBM/UserData/OS400/DHCP/dhcpsd.cfg
|
|
/QIBM/UserData/OS400/DHCP/dhcprd.cfg</pre>
|
|
</li>
|
|
</ul>
|
|
</li>
|
|
<li>Evaluate how physically accessible your LAN is. Could an outsider easily
|
|
walk into your location with a laptop and physically connect it to your LAN?
|
|
If this is an exposure, DHCP provides the capability to create a list of clients
|
|
(hardware addresses) that the DHCP server will configure. When you use this
|
|
feature, you remove some of the productivity benefit that DHCP provides to
|
|
your network administrators. However, you prevent the system from configuring
|
|
unknown workstations.</li>
|
|
<li>If possible, use a pool of IP addresses that is reusable (not architected
|
|
for the Internet). This helps prevent a workstation from outside your network
|
|
from gaining usable configuration information from the server. </li>
|
|
<li>Use the DHCP exit points if you need additional security protection. Following
|
|
is an overview of the exit points and their capabilities. <dl><dt class="dlterm">Port entry</dt>
|
|
<dd>The system calls your exit program whenever it reads a data packet from
|
|
port 67 (the DHCP port). Your exit program receives the full data packet.
|
|
It can decide whether the system should process or discard the packet. You
|
|
can use this exit point when existing DHCP screening features are not sufficient
|
|
for your needs.</dd>
|
|
<dt class="dlterm">Address assignment</dt>
|
|
<dd>The system calls your exit program whenever DHCP formally assigns an address
|
|
to a client.</dd>
|
|
<dt class="dlterm">Address release</dt>
|
|
<dd>The system calls your exit program whenever DHCP formally releases an
|
|
address and places it back in the address pool.</dd>
|
|
</dl>
|
|
</li>
|
|
</ul>
|
|
</div>
|
|
<div>
|
|
<div class="familylinks">
|
|
<div class="parentlink"><strong>Parent topic:</strong> <a href="rzamvtcpdhcp.htm" title="These topics discuss methods for securing the DHCP server for authorized users and preventing access to the DHCP server.">Security considerations for using DHCP server</a></div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html> |