<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html lang="en"><head><title>ISC-DHCP-REFERENCES: ISC DHCP References Collection</title>
<meta http-equiv="Expires" content="Fri, 13 Apr 2007 18:37:11 +0000">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="description" content="ISC DHCP References Collection">
<meta name="keywords" content="ISC, DHCP, Reference Implementation">
<meta name="generator" content="xml2rfc v1.30 (http://xml.resource.org/)">
<style type='text/css'>
<!--
body {
font-family: verdana, charcoal, helvetica, arial, sans-serif;
margin: 2em;
font-size: small ; color: #000000 ; background-color: #ffffff ; }
.title { color: #990000; font-size: x-large ;
font-weight: bold; text-align: right;
font-family: helvetica, monaco, "MS Sans Serif", arial, sans-serif;
background-color: transparent; }
.filename { color: #666666; font-size: 18px; line-height: 28px;
font-weight: bold; text-align: right;
font-family: helvetica, arial, sans-serif;
background-color: transparent; }
td.rfcbug { background-color: #000000 ; width: 30px ; height: 30px ;
text-align: justify; vertical-align: middle ; padding-top: 2px ; }
td.rfcbug span.RFC { color: #666666; font-weight: bold; text-decoration: none;
background-color: #000000 ;
font-family: monaco, charcoal, geneva, "MS Sans Serif", helvetica, verdana, sans-serif;
font-size: x-small ; }
td.rfcbug span.hotText { color: #ffffff; font-weight: normal; text-decoration: none;
text-align: center ;
font-family: charcoal, monaco, geneva, "MS Sans Serif", helvetica, verdana, sans-serif;
font-size: x-small ; background-color: #000000; }
/* info code from SantaKlauss at http://www.madaboutstyle.com/tooltip2.html */
div#counter{margin-top: 100px}
a.info{
position:relative; /*this is the key*/
z-index:24;
text-decoration:none}
a.info:hover{z-index:25; background-color:#990000 ; color: #ffffff ;}
a.info span{display: none}
a.info:hover span.info{ /*the span will display just on :hover state*/
display:block;
position:absolute;
font-size: smaller ;
top:2em; left:2em; width:15em;
padding: 2px ;
border:1px solid #333333;
background-color:#eeeeee; color:#990000;
text-align: left ;}
A { font-weight: bold; }
A:link { color: #990000; background-color: transparent ; }
A:visited { color: #333333; background-color: transparent ; }
A:active { color: #333333; background-color: transparent ; }
p { margin-left: 2em; margin-right: 2em; }
p.copyright { font-size: x-small ; }
p.toc { font-size: small ; font-weight: bold ; margin-left: 3em ;}
table.toc { margin: 0 0 0 3em; padding: 0; border: 0; vertical-align: text-top; }
td.toc { font-size: small; font-weight: bold; vertical-align: text-top; }
span.emph { font-style: italic; }
span.strong { font-weight: bold; }
span.verb, span.vbare { font-family: "Courier New", Courier, monospace ; }
span.vemph { font-style: italic; font-family: "Courier New", Courier, monospace ; }
span.vstrong { font-weight: bold; font-family: "Courier New", Courier, monospace ; }
span.vdeluxe { font-weight: bold; font-style: italic; font-family: "Courier New", Courier, monospace ; }
ol.text { margin-left: 2em; margin-right: 2em; }
ul.text { margin-left: 2em; margin-right: 2em; }
li { margin-left: 3em; }
pre { margin-left: 3em; color: #333333; background-color: transparent;
font-family: "Courier New", Courier, monospace ; font-size: small ;
text-align: left;
}
h3 { color: #333333; font-size: medium ;
font-family: helvetica, arial, sans-serif ;
background-color: transparent; }
h4 { font-size: small; font-family: helvetica, arial, sans-serif ; }
table.bug { width: 30px ; height: 15px ; }
td.bug { color: #ffffff ; background-color: #990000 ;
text-align: center ; width: 30px ; height: 15px ;
}
td.bug A.link2 { color: #ffffff ; font-weight: bold;
text-decoration: none;
font-family: monaco, charcoal, geneva, "MS Sans Serif", helvetica, sans-serif;
font-size: x-small ; background-color: transparent }
td.header { color: #ffffff; font-size: x-small ;
font-family: arial, helvetica, sans-serif; vertical-align: top;
background-color: #666666 ; width: 33% ; }
td.author { font-weight: bold; margin-left: 4em; font-size: x-small ; }
td.author-text { font-size: x-small; }
table.full { vertical-align: top ; border-collapse: collapse ;
border-style: solid solid solid solid ;
border-color: black black black black ;
font-size: small ; text-align: center ; }
table.headers, table.none { vertical-align: top ; border-collapse: collapse ;
border-style: none;
font-size: small ; text-align: center ; }
table.full th { font-weight: bold ;
border-style: solid ;
border-color: black black black black ; }
table.headers th { font-weight: bold ;
border-style: none none solid none;
border-color: black black black black ; }
table.none th { font-weight: bold ;
border-style: none; }
table.full td {
border-style: solid solid solid solid ;
border-color: #333333 #333333 #333333 #333333 ; }
table.headers td, table.none td { border-style: none; }
hr { height: 1px }
-->
</style>
</head>
<body>
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<table summary="layout" width="66%" border="0" cellpadding="0" cellspacing="0"><tr><td><table summary="layout" width="100%" border="0" cellpadding="2" cellspacing="1">
<tr><td class="header">ISC-DHCP-REFERENCES</td><td class="header">D. Hankins</td></tr>
<tr><td class="header"> </td><td class="header">ISC</td></tr>
<tr><td class="header"> </td><td class="header">August 2006</td></tr>
</table></td></tr></table>
<div align="right"><span class="title"><br />ISC DHCP References Collection</span></div>
<h3>Copyright Notice</h3>
<p>Copyright (c) 2006-2007 by Internet Systems Consortium, Inc.
("ISC")
</p>
<p>Permission to use, copy, modify, and distribute this software for
any purpose with or without fee is hereby granted, provided that the
above copyright notice and this permission notice appear in all
copies.
</p>
<p>THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
</p>
<h3>Abstract</h3>
<p>This document describes a collection of Reference material that
ISC DHCP has been implemented to.
</p><a name="toc"></a><br /><hr />
<h3>Table of Contents</h3>
<p class="toc">
<a href="#anchor1">1.</a>
Introduction<br />
<br />
<a href="#anchor2">2.</a>
Definition: Reference Implementation<br />
<br />
<a href="#anchor3">3.</a>
Low Layer References<br />
<a href="#anchor4">3.1.</a>
Ethernet Protocol References<br />
<a href="#anchor5">3.2.</a>
Token Ring Protocol References<br />
<a href="#anchor6">3.3.</a>
FDDI Protocol References<br />
<a href="#anchor7">3.4.</a>
Internet Protocol Version 4 References<br />
<a href="#anchor8">3.5.</a>
Unicast Datagram Protocol References<br />
<br />
<a href="#anchor9">4.</a>
BOOTP Protocol References<br />
<br />
<a href="#anchor10">5.</a>
DHCP Protocol References<br />
<a href="#anchor11">5.1.</a>
DHCPv4 Protocol<br />
<a href="#anchor12">5.1.1.</a>
Core Protocol References<br />
<a href="#anchor13">5.2.</a>
DHCPv6 Protocol References<br />
<a href="#anchor14">5.3.</a>
DHCP Option References<br />
<a href="#anchor15">5.3.1.</a>
Relay Agent Information Option Options<br />
<a href="#anchor16">5.3.2.</a>
Dynamic DNS Updates References<br />
<a href="#anchor17">5.3.3.</a>
Experimental: Failover References<br />
<a href="#anchor18">5.4.</a>
DHCP Procedures<br />
<br />
<a href="#rfc.references1">6.</a>
References<br />
<br />
<a href="#rfc.authors">§</a>
Author's Address<br />
</p>
<br clear="all" />
<a name="anchor1"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.1"></a><h3>1. Introduction</h3>
<p>As a little historical anecdote, ISC DHCP once packaged all the
relevant RFCs and standards documents along with the software
package. Until one day when a voice was heard from one of the
many fine institutions that build and distribute this software...
they took issue with the IETF's copyright on the RFC's. It
seems the IETF's copyrights don't allow modification of RFC's
(except for translation purposes).
</p>
<p>Our main purpose in providing the RFCs is to aid in
documentation, but since RFCs are now available widely from many
points of distribution on the Internet, there is no real need to
provide the documents themselves. So, this document has been
created in their stead, to list the various IETF RFCs one might
want to read, and to comment on how well (or poorly) we have
managed to implement them.
</p>
<a name="anchor2"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.2"></a><h3>2. Definition: Reference Implementation</h3>
<p>ISC DHCP, much like its other cousins in ISC software, is
self-described as a 'Reference Implementation.' There has been
a great deal of confusion about this term. Some people seem to
think that this term applies to any software that once passed
a piece of reference material on its way to market (but may do
quite a lot of things that aren't described in any reference, or
may choose to ignore the reference it saw entirely). Other folks
get confused by the word 'reference' and understand that to mean
that there is some special status applied to the software - that
the software itself is the reference by which all other software
is measured. Something along the lines of being "The DHCP
Protocol's Reference Clock," it is supposed.
</p>
<p>The truth is actually quite a lot simpler. Reference
implementations are software packages which were written
to behave precisely as appears in reference material. They
are written "to match reference."
</p>
<p>If the software has a behaviour that manifests itself
externally (whether it be something as simple as the 'wire
format' or something higher level, such as a complicated
behaviour that arises from multiple message exchanges), that
behaviour must be found in a reference document.
</p>
<p>Anything else is a bug, the only question is whether the
bug is in reference or software (failing to implement the
reference).
</p>
<p>This means:
</p>
<ul class="text">
<li>To produce new externally-visible behaviour, one must first
provide a reference.
</li>
<li>Before changing externally visible behaviour to work around
simple incompatibilities in any other implementation, one must
first provide a reference.
</li>
</ul>
<p>That is the lofty goal, at any rate. It's well understood that,
especially because the ISC DHCP Software package has not always been
held to this standard (but not entirely due to it), there are many
non-referenced behaviours within ISC DHCP.
</p>
<p>The primary goal of reference implementation is to prove the
reference material. If the reference material is good, then you
should be able to sit down and write a program that implements the
reference, to the word, and come to an implementation that
is distinguishable from others in the details, but not in the
facts of operating the protocol. This means that there is no
need for 'special knowledge' to work around arcane problems that
were left undocumented. No secret handshakes need to be learned
to be imparted with the necessary "real documentation".
</p>
<p>Also, by accepting only reference as the guidebook for ISC
DHCP's software implementation, anyone who can make an impact on
the color texture or form of that reference has a (somewhat
indirect) voice in ISC DHCP's software design. As the IETF RFC's
have been selected as the source of reference, that means everyone
on the Internet with the will to participate has a say.
</p>
<a name="anchor3"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.3"></a><h3>3. Low Layer References</h3>
<p>It may surprise you to realize that ISC DHCP implements 802.1
'Ethernet' framing, Token Ring, and FDDI. In order to bridge the
gap there between these physical and DHCP layers, it must also
implement IP and UDP framing.
</p>
<p>The reason for this stems from Unix systems' handling of BSD
sockets (the general way one might engage in transmission of UDP
packets) on unconfigured interfaces, or even the handling of
broadcast addressing on configured interfaces.
</p>
<p>There are a few things that DHCP servers, relays, and clients all
need to do in order to speak the DHCP protocol in strict compliance
with <a class="info" href="#RFC2131">RFC2131<span> (</span><span class="info">Droms, R., “Dynamic Host Configuration Protocol,” March 1997.</span><span>)</span></a> [8].
</p>
<ol class="text">
<li>Transmit a UDP packet from IP:0.0.0.0 Ethernet:Self, destined to
IP:255.255.255.255 LinkLayer:Broadcast on an unconfigured (no IP
address yet) interface.
</li>
<li>Receive a UDP packet from IP:remote-system LinkLayer:remote-system,
destined to IP:255.255.255.255 LinkLayer:Broadcast, again on an
unconfigured interface.
</li>
<li>Transmit a UDP packet from IP:Self, Ethernet:Seelf, destined to
IP:remote-system LinkLayer:remote-system, without transmitting a
single ARP.
</li>
<li>And of course the simple case, a regular IP unicast that is
routed via the usual means (so it may be direct to a local system,
with ARP providing the glue, or it may be to a remote system via
one or more routers as normal). In this case, the interfaces are
always configured.
</li>
</ol>
<p>The above isn't as simple as it sounds on a regular BSD socket.
Many unix implementations will transmit broadcasts not to
255.255.255.255, but to x.y.z.255 (where x.y.z is the system's local
subnet). Such packets are not received by several known DHCP client
implementations - and it's not their fault, <a class="info" href="#RFC2131">RFC2131<span> (</span><span class="info">Droms, R., “Dynamic Host Configuration Protocol,” March 1997.</span><span>)</span></a> [8] very explicitly demands that these packets' IP
destination addresses be set to 255.255.255.255.
</p>
<p>Receiving packets sent to 255.255.255.255 isn't a problem on most
modern unixes...so long as the interface is configured. When there
is no IPv4 address on the interface, things become much more murky.
</p>
<p>So, for this convoluted and unfortunate state of affairs in the
unix systems of the day ISC DHCP was manufactured, in order to do
what it needs not only to implement the reference but to interoperate
with other implementations, the software must create some form of
raw socket to operate on.
</p>
<p>What it actually does is create, for each interface detected on
the system, a Berkeley Packet Filter socket (or equivalent), and
program it with a filter that brings in only DHCP packets. A
"fallback" UDP Berkeley socket is generally also created, a single
one no matter how many interfaces. Should the software need to
transmit a contrived packet to the local network the packet is
formed piece by piece and transmitted via the BPF socket. Hence
the need to implement many forms of Link Layer framing and above.
The software gets away with not having to implement IP routing
tables as well by simply utilizing the aforementioned 'fallback'
UDP socket when unicasting between two configured systems is the
need.
</p>
<p>Modern unixes have opened up some facilities that diminish how
much of this sort of nefarious kludgery is necessary, but have not
found the state of affairs absolutely absolved. In particular,
one might now unicast without ARP by inserting an entry into the
ARP cache prior to transmitting. Unconfigured interfaces remain
the sticking point, however...on virtually no modern unixes is
it possible to receive broadcast packets unless a local IPv4
address has been configured, unless it is done with raw sockets.
</p>
<a name="anchor4"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.3.1"></a><h3>3.1. Ethernet Protocol References</h3>
<p>ISC DHCP Implements Ethernet Version 2 ("DIX"), which is a variant
of IEEE 802.2. No good reference of this framing is known to exist
at this time, but it is vaguely described in <a class="info" href="#RFC0894">RFC894<span> (</span><span class="info">Hornig, C., “Standard for the transmission of IP datagrams over Ethernet networks,” April 1984.</span><span>)</span></a> [3] (see the section titled "Packet format"), and
the following URL is also thought to be useful.
</p>
<p>http://en.wikipedia.org/wiki/DIX
</p>
<a name="anchor5"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.3.2"></a><h3>3.2. Token Ring Protocol References</h3>
<p>IEEE 802.5 defines the Token Ring framing format used by ISC
DHCP.
</p>
<a name="anchor6"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.3.3"></a><h3>3.3. FDDI Protocol References</h3>
<p><a class="info" href="#RFC1188">RFC1188<span> (</span><span class="info">Katz, D., “Proposed Standard for the Transmission of IP Datagrams over FDDI Networks,” October 1990.</span><span>)</span></a> [6] is the most helpful
reference ISC DHCP has used to form FDDI packets.
</p>
<a name="anchor7"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.3.4"></a><h3>3.4. Internet Protocol Version 4 References</h3>
<p><a class="info" href="#RFC0760">RFC760<span> (</span><span class="info">Postel, J., “DoD standard Internet Protocol,” January 1980.</span><span>)</span></a> [1] fundamentally defines the
bare IPv4 protocol which ISC DHCP implements.
</p>
<a name="anchor8"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.3.5"></a><h3>3.5. Unicast Datagram Protocol References</h3>
<p><a class="info" href="#RFC0768">RFC768<span> (</span><span class="info">Postel, J., “User Datagram Protocol,” August 1980.</span><span>)</span></a> [2] defines the User Datagram
Protocol that ultimately carries the DHCP or BOOTP protocol. The
destination DHCP server port is 67, the client port is 68. Source
ports are irrelevant.
</p>
<a name="anchor9"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.4"></a><h3>4. BOOTP Protocol References</h3>
<p>The DHCP Protocol is strange among protocols in that it is
grafted over the top of another protocol - BOOTP (but we don't
call it "DHCP over BOOTP" like we do, say "TCP over IP"). BOOTP
and DHCP share UDP packet formats - DHCP is merely a conventional
use of both BOOTP header fields and the trailing 'options' space.
</p>
<p>The ISC DHCP server supports BOOTP clients conforming to
<a class="info" href="#RFC0951">RFC951<span> (</span><span class="info">Croft, B. and J. Gilmore, “Bootstrap Protocol,” September 1985.</span><span>)</span></a> [4] and <a class="info" href="#RFC1542">RFC1542<span> (</span><span class="info">Wimer, W., “Clarifications and Extensions for the Bootstrap Protocol,” October 1993.</span><span>)</span></a> [7].
</p>
<a name="anchor10"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.5"></a><h3>5. DHCP Protocol References</h3>
<a name="anchor11"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.5.1"></a><h3>5.1. DHCPv4 Protocol</h3>
<p>"The DHCP[v4] Protocol" is not defined in a single document. The
following collection of references of what ISC DHCP terms "The
DHCPv4 Protocol".
</p>
<a name="anchor12"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.5.1.1"></a><h3>5.1.1. Core Protocol References</h3>
<p><a class="info" href="#RFC2131">RFC2131<span> (</span><span class="info">Droms, R., “Dynamic Host Configuration Protocol,” March 1997.</span><span>)</span></a> [8] defines the protocol format
and procedures. ISC DHCP is not known to diverge from this document
in any way. There are, however, a few points on which different
implementations have arisen out of vagueries in the document.
DHCP Clients exist which, at one time, present themselves as using
a Client Identifier Option which is equal to the client's hardware
address. Later, the client transmits DHCP packets with no Client
Identifier Option present - essentially identifying themselves using
the hardware address. Some DHCP Servers have been developed which
identify this client as a single client. ISC has interpreted
RFC2131 to indicate that these clients must be treated as two
separate entities (and hence two, separate addresses). Client
behaviour (Embedded Windows products) has developed that relies on
the former implementation, and hence is incompatible with the
latter. Also, RFC2131 demands explicitly that some header fields
be zeroed upon certain message types. The ISC DHCP Server instead
copies many of these fields from the packet received from the client
or relay, which may not be zero. It is not known if there is a good
reason for this that has not been documented.
</p>
<p><a class="info" href="#RFC2132">RFC2132<span> (</span><span class="info">Alexander, S. and R. Droms, “DHCP Options and BOOTP Vendor Extensions,” March 1997.</span><span>)</span></a> [9] defines the initial set of
DHCP Options and provides a great deal of guidance on how to go about
formatting and processing options. The document unfortunately
waffles to a great extent about the NULL termination of DHCP Options,
and some DHCP Clients (Windows 95) have been implemented that rely
upon DHCP Options containing text strings to be NULL-terminated (or
else they crash). So, ISC DHCP detects if clients null-terminate the
host-name option and, if so, null terminates any text options it
transmits to the client. It also removes NULL termination from any
known text option it receives prior to any other processing.
</p>
<a name="anchor13"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.5.2"></a><h3>5.2. DHCPv6 Protocol References</h3>
<p>For now there is only one document that specifies the DHCPv6
protocol (there have been no updates yet), <a class="info" href="#RFC3315">RFC3315<span> (</span><span class="info">Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C., and M. Carney, “Dynamic Host Configuration Protocol for IPv6 (DHCPv6),” July 2003.</span><span>)</span></a> [21].
</p>
<p>Support for DHCPv6 was added first in version 4.0.0. The server
and client support only IA_NA. While the server does support multiple
IA_NAs within one packet from the client, our client only supports
sending one. There is no relay support.
</p>
<p>DHCPv6 introduces some new and uncomfortable ideas to the common
software library.
</p>
<ol class="text">
<li>Options of zero length are normal in DHCPv6. Currently, all
ISC DHCP software treats zero-length options as errors.
</li>
<li>Options sometimes may appear multiple times. The common
library used to treat all appearance of multiple options as
specified in RFC2131 - to be concatenated. DHCPv6 options
may sometimes appear multiple times (such as with IA_NA or
IAADDR), but often must not.
</li>
<li>The same option space appears in DHCPv6 packets multiple times.
If the packet was got via a relay, then the client's packet is
stored to an option within the relay's packet...if there were two
relays, this recurses. At each of these steps, the root "DHCPv6
option space" is used. Further, a client packet may contain an
IA_NA, which may contain an IAADDR - but really, in an abstract
sense, this is again re-encapsulation of the DHCPv6 option space
beneath options it also contains.
</li>
</ol>
<p>Precisely how to correctly support the above conundrums has not
quite yet been settled, so support is incomplete.
</p>
<a name="anchor14"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.5.3"></a><h3>5.3. DHCP Option References</h3>
<p><a class="info" href="#RFC2241">RFC2241<span> (</span><span class="info">Provan, D., “DHCP Options for Novell Directory Services,” November 1997.</span><span>)</span></a> [10] defines options for
Novell Directory Services.
</p>
<p><a class="info" href="#RFC2242">RFC2242<span> (</span><span class="info">Droms, R. and K. Fong, “NetWare/IP Domain Name and Information,” November 1997.</span><span>)</span></a> [11] defines an encapsulated
option space for NWIP configuration.
</p>
<p><a class="info" href="#RFC2485">RFC2485<span> (</span><span class="info">Drach, S., “DHCP Option for The Open Group's User Authentication Protocol,” January 1999.</span><span>)</span></a> [12] defines the Open Group's
UAP option.
</p>
<p><a class="info" href="#RFC2610">RFC2610<span> (</span><span class="info">Perkins, C. and E. Guttman, “DHCP Options for Service Location Protocol,” June 1999.</span><span>)</span></a> [13] defines options for
the Service Location Protocol (SLP).
</p>
<p><a class="info" href="#RFC2937">RFC2937<span> (</span><span class="info">Smith, C., “The Name Service Search Option for DHCP,” September 2000.</span><span>)</span></a> [14] defines the Name Service
Search Option (not to be confused with the domain-search option).
The Name Service Search Option allows eg nsswitch.conf to be
reconfigured via dhcp. The ISC DHCP server implements this option,
and the ISC DHCP client is compatible...but does not by default
install this option's value. One would need to make their relevant
dhclient-script process this option in a way that is suitable for
the system.
</p>
<p><a class="info" href="#RFC3004">RFC3004<span> (</span><span class="info">Stump, G., Droms, R., Gu, Y., Vyaghrapuri, R., Demirtjis, A., Beser, B., and J. Privat, “The User Class Option for DHCP,” November 2000.</span><span>)</span></a> [16] defines the User-Class
option. Note carefully that ISC DHCP currently does not implement
to this reference, but has (inexplicably) selected an incompatible
format: a plain text string.
</p>
<p><a class="info" href="#RFC3011">RFC3011<span> (</span><span class="info">Waters, G., “The IPv4 Subnet Selection Option for DHCP,” November 2000.</span><span>)</span></a> [17] defines the Subnet-Selection
plain DHCPv4 option. Do not confuse this option with the relay agent
"link selection" sub-option, although their behaviour is similar.
</p>
<p><a class="info" href="#RFC3319">RFC3319<span> (</span><span class="info">Schulzrinne, H. and B. Volz, “Dynamic Host Configuration Protocol (DHCPv6) Options for Session Initiation Protocol (SIP) Servers,” July 2003.</span><span>)</span></a> [22] defines the SIP server
options for DHCPv6.
</p>
<p><a class="info" href="#RFC3396">RFC3396<span> (</span><span class="info">Lemon, T. and S. Cheshire, “Encoding Long Options in the Dynamic Host Configuration Protocol (DHCPv4),” November 2002.</span><span>)</span></a> [23] documents both how long
options may be encoded in DHCPv4 packets, and also how multiple
instances of the same option code within a DHCPv4 packet will be
decoded by receivers.
</p>
<p><a class="info" href="#RFC3397">RFC3397<span> (</span><span class="info">Aboba, B. and S. Cheshire, “Dynamic Host Configuration Protocol (DHCP) Domain Search Option,” November 2002.</span><span>)</span></a> [24] documents the Domain-Search
Option, which allows the configuration of the /etc/resolv.conf
'search' parameter in a way that is <a class="info" href="#RFC1035">RFC1035<span> (</span><span class="info">Mockapetris, P., “Domain names - implementation and specification,” November 1987.</span><span>)</span></a> [5] wire format compatible (in fact, it uses the RFC1035 wire
format). ISC DHCP has both client and server support, and supports
RFC1035 name compression.
</p>
<p><a class="info" href="#RFC3646">RFC3646<span> (</span><span class="info">Droms, R., “DNS Configuration options for Dynamic Host Configuration Protocol for IPv6 (DHCPv6),” December 2003.</span><span>)</span></a> [27] documents the DHCPv6
name-servers and domain-search options.
</p>
<p><a class="info" href="#RFC3633">RFC3633<span> (</span><span class="info">Troan, O. and R. Droms, “IPv6 Prefix Options for Dynamic Host Configuration Protocol (DHCP) version 6,” December 2003.</span><span>)</span></a> [26] documents the Identity
Association Prefix Delegation, which is included here for protocol
wire reference, but which is not supported by ISC DHCP.
</p>
<p><a class="info" href="#RFC3679">RFC3679<span> (</span><span class="info">Droms, R., “Unused Dynamic Host Configuration Protocol (DHCP) Option Codes,” January 2004.</span><span>)</span></a> [28] documents a number of
options that were documented earlier in history, but were not
made use of.
</p>
<p><a class="info" href="#RFC3898">RFC3898<span> (</span><span class="info">Kalusivalingam, V., “Network Information Service (NIS) Configuration Options for Dynamic Host Configuration Protocol for IPv6 (DHCPv6),” October 2004.</span><span>)</span></a> [29] documents four NIS options
for delivering NIS servers and domain information in DHCPv6.
</p>
<p><a class="info" href="#RFC3925">RFC3925<span> (</span><span class="info">Littlefield, J., “Vendor-Identifying Vendor Options for Dynamic Host Configuration Protocol version 4 (DHCPv4),” October 2004.</span><span>)</span></a> [30] documents a pair of
Enterprise-ID delimited option spaces for vendors to use in order
to inform servers of their "vendor class" (sort of like 'uname'
or 'who and what am I'), and a means to deliver vendor-specific
and vendor-documented option codes and values.
</p>
<p><a class="info" href="#RFC3942">RFC3942<span> (</span><span class="info">Volz, B., “Reclassifying Dynamic Host Configuration Protocol version 4 (DHCPv4) Options,” November 2004.</span><span>)</span></a> [31] redefined the 'site local'
option space.
</p>
<p><a class="info" href="#RFC4075">RFC4075<span> (</span><span class="info">Kalusivalingam, V., “Simple Network Time Protocol (SNTP) Configuration Option for DHCPv6,” May 2005.</span><span>)</span></a> [32] defines the DHCPv6 SNTP
Servers option.
</p>
<p><a class="info" href="#RFC4242">RFC4242<span> (</span><span class="info">Venaas, S., Chown, T., and B. Volz, “Information Refresh Time Option for Dynamic Host Configuration Protocol for IPv6 (DHCPv6),” November 2005.</span><span>)</span></a> [33] defines the Information
Refresh Time option, which advises DHCPv6 Information-Request
clients to return for updated information.
</p>
<p><a class="info" href="#RFC4280">RFC4280<span> (</span><span class="info">Chowdhury, K., Yegani, P., and L. Madour, “Dynamic Host Configuration Protocol (DHCP) Options for Broadcast and Multicast Control Servers,” November 2005.</span><span>)</span></a> [34] defines two BCMS server
options.
</p>
<p><a class="info" href="#RFC4388">RFC4388<span> (</span><span class="info">Woundy, R. and K. Kinnear, “Dynamic Host Configuration Protocol (DHCP) Leasequery,” February 2006.</span><span>)</span></a> [35] defined the DHCPv4
LEASEQUERY message type and a number of suitable response messages,
for the purpose of sharing information about DHCP served addresses
and clients.
</p>
<p><a class="info" href="#RFC4580">RFC4580><span> (</span><span class="info">Volz, B., “Dynamic Host Configuration Protocol for IPv6 (DHCPv6) Relay Agent Subscriber-ID Option,” June 2006.</span><span>)</span></a> [36] defines a DHCPv6
subscriber-id option, which is similar in principle to the DHCPv4
relay agent option of the same name.
</p>
<p><a class="info" href="#RFC4649">RFC4649<span> (</span><span class="info">Volz, B., “Dynamic Host Configuration Protocol for IPv6 (DHCPv6) Relay Agent Remote-ID Option,” August 2006.</span><span>)</span></a> [37] defines a DHCPv6 remote-id
option, which is similar in principle to the DHCPv4 relay agent
remote-id.
</p>
<a name="anchor15"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.5.3.1"></a><h3>5.3.1. Relay Agent Information Option Options</h3>
<p><a class="info" href="#RFC3046">RFC3046<span> (</span><span class="info">Patrick, M., “DHCP Relay Agent Information Option,” January 2001.</span><span>)</span></a> [18] defines the Relay Agent
Information Option and provides a number of sub-option
definitions.
</p>
<p><a class="info" href="#RFC3256">RFC3256<span> (</span><span class="info">Jones, D. and R. Woundy, “The DOCSIS (Data-Over-Cable Service Interface Specifications) Device Class DHCP (Dynamic Host Configuration Protocol) Relay Agent Information Sub-option,” April 2002.</span><span>)</span></a> [20] defines the DOCSIS Device
Class sub-option.
</p>
<p><a class="info" href="#RFC3527">RFC3527<span> (</span><span class="info">Kinnear, K., Stapp, M., Johnson, R., and J. Kumarasamy, “Link Selection sub-option for the Relay Agent Information Option for DHCPv4,” April 2003.</span><span>)</span></a> [25] defines the Link Selection
sub-option.
</p>
<a name="anchor16"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.5.3.2"></a><h3>5.3.2. Dynamic DNS Updates References</h3>
<p>The collection of documents that describe the standards-based
method to update dns names of DHCP clients starts most easily
with <a class="info" href="#RFC4703">RFC4703<span> (</span><span class="info">Stapp, M. and B. Volz, “Resolution of Fully Qualified Domain Name (FQDN) Conflicts among Dynamic Host Configuration Protocol (DHCP) Clients,” October 2006.</span><span>)</span></a> [40] to define the overall
architecture, travels through RFCs <a class="info" href="#RFC4702">4702<span> (</span><span class="info">Stapp, M., Volz, B., and Y. Rekhter, “The Dynamic Host Configuration Protocol (DHCP) Client Fully Qualified Domain Name (FQDN) Option,” October 2006.</span><span>)</span></a> [39]
and <a class="info" href="#RFC4704">4704<span> (</span><span class="info">Volz, B., “The Dynamic Host Configuration Protocol for IPv6 (DHCPv6) Client Fully Qualified Domain Name (FQDN) Option,” October 2006.</span><span>)</span></a> [41] to describe the DHCPv4 and
DHCPv6 FQDN options (to carry the client name), and ends up at
<a class="info" href="#RFC4701">RFC4701<span> (</span><span class="info">Stapp, M., Lemon, T., and A. Gustafsson, “A DNS Resource Record (RR) for Encoding Dynamic Host Configuration Protocol (DHCP) Information (DHCID RR),” October 2006.</span><span>)</span></a> [38] which describes the DHCID
RR used in DNS to perform a kind of atomic locking.
</p>
<p>ISC DHCP adoped early versions of these documents, and has not
yet synched up with the final standards versions.
</p>
<p>For RFCs 4702 and 4704, the 'N' bit is not yet supported. The
result is that it is always set zero, and is ignored if set.
</p>
<p>For RFC4701, which is used to match client identities with names
in the DNS as part of name conflict resolution. Note that ISC DHCP's
implementation of DHCIDs vary wildly from this specification.
First, ISC DHCP uses a TXT record in which the contents are stored
in hexadecimal. Second, there is a flaw in the selection of the
'Identifier Type', which results in a completely different value
being selected than was defined in an older revision of this
document...also this field is one byte prior to hexadecimal
encoding rather than two. Third, ISC DHCP does not use a digest
type code. Rather, all values for such TXT records are reached
via an MD5 sum. In short, nothing is compatible, but the
principle of the TXT record is the same as the standard DHCID
record. However, for DHCPv6 FQDN, we do use DHCID type code '2',
as no other value really makes sense in our context.
</p>
<a name="anchor17"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.5.3.3"></a><h3>5.3.3. Experimental: Failover References</h3>
<p>The Failover Protocol defines a means by which two DHCP Servers
can share all the relevant information about leases granted to
DHCP clients on given networks, so that one of the two servers may
fail and be survived by a server that can act responsibly.
</p>
<p>Unfortunately it has been quite some years since the last time
this document was edited, and the authors no longer show any
interest in fielding comments or improving the document.
</p>
<p>The status of this protocol is very unsure, but ISC's
implementation of it has proven stable and suitable for use in
sizable production environments.
</p>
<p><a class="info" href="#draft-failover">draft-ietf-dhc-failover-12.txt<span> (</span><span class="info">Droms, R., “DHCP Failover Protocol,” March 2003.</span><span>)</span></a> [42]
describes the Failover Protocol. In addition to what is described
in this document, ISC DHCP has elected to make some experimental
changes that may be revoked in a future version of ISC DHCP (if the
draft authors do not adopt the new behaviour). Specifically, ISC
DHCP's POOLREQ behaviour differs substantially from what is
documented in the draft, and the server also implements a form of
'MAC Address Affinity' which is not described in the failover
document. The full nature of these changes have been described on
the IETF DHC WG mailing list (which has archives), and also in ISC
DHCP's manual pages. Also note that although this document
references a RECOVER-WAIT state, it does not document a protocol
number assignment for this state. As a consequence, ISC DHCP has
elected to use the value 254.
</p>
<p><a class="info" href="#RFC3074">RFC3074<span> (</span><span class="info">Volz, B., Gonczi, S., Lemon, T., and R. Stevens, “DHC Load Balancing Algorithm,” February 2001.</span><span>)</span></a> [19] describes the Load Balancing
Algorithm (LBA) that ISC DHCP uses in concert with the Failover
protocol. Note that versions 3.0.* are known to misimplement the
hash algorithm (it will only use the low 4 bits of every byte of
the hash bucket array).
</p>
<a name="anchor18"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<a name="rfc.section.5.4"></a><h3>5.4. DHCP Procedures</h3>
<p><a class="info" href="#RFC2939">RFC2939<span> (</span><span class="info">Droms, R., “Procedures and IANA Guidelines for Definition of New DHCP Options and Message Types,” September 2000.</span><span>)</span></a> [15] explains how to go about
obtaining a new DHCP Option code assignment.
</p>
<a name="rfc.references1"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<h3>6. References</h3>
<table width="99%" border="0">
<tr><td class="author-text" valign="top"><a name="RFC0760">[1]</a></td>
<td class="author-text">Postel, J., “<a href="ftp://ftp.isi.edu/in-notes/rfc760.txt">DoD standard Internet Protocol</a>,” RFC 760, January 1980.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC0768">[2]</a></td>
<td class="author-text">Postel, J., “<a href="ftp://ftp.isi.edu/in-notes/rfc768.txt">User Datagram Protocol</a>,” STD 6, RFC 768, August 1980.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC0894">[3]</a></td>
<td class="author-text">Hornig, C., “<a href="ftp://ftp.isi.edu/in-notes/rfc894.txt">Standard for the transmission of IP datagrams over Ethernet networks</a>,” STD 41, RFC 894, April 1984.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC0951">[4]</a></td>
<td class="author-text">Croft, B. and J. Gilmore, “<a href="ftp://ftp.isi.edu/in-notes/rfc951.txt">Bootstrap Protocol</a>,” RFC 951, September 1985.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC1035">[5]</a></td>
<td class="author-text">Mockapetris, P., “<a href="ftp://ftp.isi.edu/in-notes/rfc1035.txt">Domain names - implementation and specification</a>,” STD 13, RFC 1035, November 1987.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC1188">[6]</a></td>
<td class="author-text"><a href="mailto:dkatz@merit.edu">Katz, D.</a>, “<a href="ftp://ftp.isi.edu/in-notes/rfc1188.txt">Proposed Standard for the Transmission of IP Datagrams over FDDI Networks</a>,” RFC 1188, October 1990.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC1542">[7]</a></td>
<td class="author-text"><a href="mailto:Walter.Wimer@CMU.EDU">Wimer, W.</a>, “<a href="ftp://ftp.isi.edu/in-notes/rfc1542.txt">Clarifications and Extensions for the Bootstrap Protocol</a>,” RFC 1542, October 1993.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC2131">[8]</a></td>
<td class="author-text"><a href="mailto:droms@bucknell.edu">Droms, R.</a>, “<a href="ftp://ftp.isi.edu/in-notes/rfc2131.txt">Dynamic Host Configuration Protocol</a>,” RFC 2131, March 1997 (<a href="ftp://ftp.isi.edu/in-notes/rfc2131.txt">TXT</a>, <a href="http://xml.resource.org/public/rfc/html/rfc2131.html">HTML</a>, <a href="http://xml.resource.org/public/rfc/xml/rfc2131.xml">XML</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC2132">[9]</a></td>
<td class="author-text"><a href="mailto:sca@engr.sgi.com">Alexander, S.</a> and <a href="mailto:droms@bucknell.edu">R. Droms</a>, “<a href="ftp://ftp.isi.edu/in-notes/rfc2132.txt">DHCP Options and BOOTP Vendor Extensions</a>,” RFC 2132, March 1997 (<a href="ftp://ftp.isi.edu/in-notes/rfc2132.txt">TXT</a>, <a href="http://xml.resource.org/public/rfc/html/rfc2132.html">HTML</a>, <a href="http://xml.resource.org/public/rfc/xml/rfc2132.xml">XML</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC2241">[10]</a></td>
<td class="author-text"><a href="mailto:donp@Novell.Com">Provan, D.</a>, “<a href="ftp://ftp.isi.edu/in-notes/rfc2241.txt">DHCP Options for Novell Directory Services</a>,” RFC 2241, November 1997 (<a href="ftp://ftp.isi.edu/in-notes/rfc2241.txt">TXT</a>, <a href="http://xml.resource.org/public/rfc/html/rfc2241.html">HTML</a>, <a href="http://xml.resource.org/public/rfc/xml/rfc2241.xml">XML</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC2242">[11]</a></td>
<td class="author-text"><a href="mailto:droms@bucknell.edu">Droms, R.</a> and <a href="mailto:kfong@novell.com">K. Fong</a>, “<a href="ftp://ftp.isi.edu/in-notes/rfc2242.txt">NetWare/IP Domain Name and Information</a>,” RFC 2242, November 1997 (<a href="ftp://ftp.isi.edu/in-notes/rfc2242.txt">TXT</a>, <a href="http://xml.resource.org/public/rfc/html/rfc2242.html">HTML</a>, <a href="http://xml.resource.org/public/rfc/xml/rfc2242.xml">XML</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC2485">[12]</a></td>
<td class="author-text"><a href="mailto:drach@sun.com">Drach, S.</a>, “<a href="ftp://ftp.isi.edu/in-notes/rfc2485.txt">DHCP Option for The Open Group's User Authentication Protocol</a>,” RFC 2485, January 1999 (<a href="ftp://ftp.isi.edu/in-notes/rfc2485.txt">TXT</a>, <a href="http://xml.resource.org/public/rfc/html/rfc2485.html">HTML</a>, <a href="http://xml.resource.org/public/rfc/xml/rfc2485.xml">XML</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC2610">[13]</a></td>
<td class="author-text"><a href="mailto:Charles.Perkins@Sun.Com">Perkins, C.</a> and <a href="mailto:Erik.Guttman@Sun.Com">E. Guttman</a>, “<a href="ftp://ftp.isi.edu/in-notes/rfc2610.txt">DHCP Options for Service Location Protocol</a>,” RFC 2610, June 1999.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC2937">[14]</a></td>
<td class="author-text">Smith, C., “<a href="ftp://ftp.isi.edu/in-notes/rfc2937.txt">The Name Service Search Option for DHCP</a>,” RFC 2937, September 2000.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC2939">[15]</a></td>
<td class="author-text">Droms, R., “<a href="ftp://ftp.isi.edu/in-notes/rfc2939.txt">Procedures and IANA Guidelines for Definition of New DHCP Options and Message Types</a>,” BCP 43, RFC 2939, September 2000.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3004">[16]</a></td>
<td class="author-text">Stump, G., Droms, R., Gu, Y., Vyaghrapuri, R., Demirtjis, A., Beser, B., and J. Privat, “<a href="ftp://ftp.isi.edu/in-notes/rfc3004.txt">The User Class Option for DHCP</a>,” RFC 3004, November 2000.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3011">[17]</a></td>
<td class="author-text">Waters, G., “<a href="ftp://ftp.isi.edu/in-notes/rfc3011.txt">The IPv4 Subnet Selection Option for DHCP</a>,” RFC 3011, November 2000.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3046">[18]</a></td>
<td class="author-text">Patrick, M., “<a href="ftp://ftp.isi.edu/in-notes/rfc3046.txt">DHCP Relay Agent Information Option</a>,” RFC 3046, January 2001.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3074">[19]</a></td>
<td class="author-text">Volz, B., Gonczi, S., Lemon, T., and R. Stevens, “<a href="ftp://ftp.isi.edu/in-notes/rfc3074.txt">DHC Load Balancing Algorithm</a>,” RFC 3074, February 2001.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3256">[20]</a></td>
<td class="author-text">Jones, D. and R. Woundy, “<a href="ftp://ftp.isi.edu/in-notes/rfc3256.txt">The DOCSIS (Data-Over-Cable Service Interface Specifications) Device Class DHCP (Dynamic Host Configuration Protocol) Relay Agent Information Sub-option</a>,” RFC 3256, April 2002.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3315">[21]</a></td>
<td class="author-text">Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C., and M. Carney, “<a href="ftp://ftp.isi.edu/in-notes/rfc3315.txt">Dynamic Host Configuration Protocol for IPv6 (DHCPv6)</a>,” RFC 3315, July 2003.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3319">[22]</a></td>
<td class="author-text">Schulzrinne, H. and B. Volz, “<a href="ftp://ftp.isi.edu/in-notes/rfc3319.txt">Dynamic Host Configuration Protocol (DHCPv6) Options for Session Initiation Protocol (SIP) Servers</a>,” RFC 3319, July 2003.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3396">[23]</a></td>
<td class="author-text">Lemon, T. and S. Cheshire, “<a href="ftp://ftp.isi.edu/in-notes/rfc3396.txt">Encoding Long Options in the Dynamic Host Configuration Protocol (DHCPv4)</a>,” RFC 3396, November 2002.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3397">[24]</a></td>
<td class="author-text">Aboba, B. and S. Cheshire, “<a href="ftp://ftp.isi.edu/in-notes/rfc3397.txt">Dynamic Host Configuration Protocol (DHCP) Domain Search Option</a>,” RFC 3397, November 2002.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3527">[25]</a></td>
<td class="author-text">Kinnear, K., Stapp, M., Johnson, R., and J. Kumarasamy, “<a href="ftp://ftp.isi.edu/in-notes/rfc3527.txt">Link Selection sub-option for the Relay Agent Information Option for DHCPv4</a>,” RFC 3527, April 2003.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3633">[26]</a></td>
<td class="author-text">Troan, O. and R. Droms, “<a href="ftp://ftp.isi.edu/in-notes/rfc3633.txt">IPv6 Prefix Options for Dynamic Host Configuration Protocol (DHCP) version 6</a>,” RFC 3633, December 2003.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3646">[27]</a></td>
<td class="author-text">Droms, R., “<a href="ftp://ftp.isi.edu/in-notes/rfc3646.txt">DNS Configuration options for Dynamic Host Configuration Protocol for IPv6 (DHCPv6)</a>,” RFC 3646, December 2003.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3679">[28]</a></td>
<td class="author-text">Droms, R., “<a href="ftp://ftp.isi.edu/in-notes/rfc3679.txt">Unused Dynamic Host Configuration Protocol (DHCP) Option Codes</a>,” RFC 3679, January 2004.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3898">[29]</a></td>
<td class="author-text">Kalusivalingam, V., “<a href="ftp://ftp.isi.edu/in-notes/rfc3898.txt">Network Information Service (NIS) Configuration Options for Dynamic Host Configuration Protocol for IPv6 (DHCPv6)</a>,” RFC 3898, October 2004.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3925">[30]</a></td>
<td class="author-text">Littlefield, J., “<a href="ftp://ftp.isi.edu/in-notes/rfc3925.txt">Vendor-Identifying Vendor Options for Dynamic Host Configuration Protocol version 4 (DHCPv4)</a>,” RFC 3925, October 2004.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3942">[31]</a></td>
<td class="author-text">Volz, B., “<a href="ftp://ftp.isi.edu/in-notes/rfc3942.txt">Reclassifying Dynamic Host Configuration Protocol version 4 (DHCPv4) Options</a>,” RFC 3942, November 2004.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4075">[32]</a></td>
<td class="author-text">Kalusivalingam, V., “<a href="ftp://ftp.isi.edu/in-notes/rfc4075.txt">Simple Network Time Protocol (SNTP) Configuration Option for DHCPv6</a>,” RFC 4075, May 2005.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4242">[33]</a></td>
<td class="author-text">Venaas, S., Chown, T., and B. Volz, “<a href="ftp://ftp.isi.edu/in-notes/rfc4242.txt">Information Refresh Time Option for Dynamic Host Configuration Protocol for IPv6 (DHCPv6)</a>,” RFC 4242, November 2005.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4280">[34]</a></td>
<td class="author-text">Chowdhury, K., Yegani, P., and L. Madour, “<a href="ftp://ftp.isi.edu/in-notes/rfc4280.txt">Dynamic Host Configuration Protocol (DHCP) Options for Broadcast and Multicast Control Servers</a>,” RFC 4280, November 2005.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4388">[35]</a></td>
<td class="author-text">Woundy, R. and K. Kinnear, “<a href="ftp://ftp.isi.edu/in-notes/rfc4388.txt">Dynamic Host Configuration Protocol (DHCP) Leasequery</a>,” RFC 4388, February 2006.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4580">[36]</a></td>
<td class="author-text">Volz, B., “<a href="ftp://ftp.isi.edu/in-notes/rfc4580.txt">Dynamic Host Configuration Protocol for IPv6 (DHCPv6) Relay Agent Subscriber-ID Option</a>,” RFC 4580, June 2006.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4649">[37]</a></td>
<td class="author-text">Volz, B., “<a href="ftp://ftp.isi.edu/in-notes/rfc4649.txt">Dynamic Host Configuration Protocol for IPv6 (DHCPv6) Relay Agent Remote-ID Option</a>,” RFC 4649, August 2006.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4701">[38]</a></td>
<td class="author-text">Stapp, M., Lemon, T., and A. Gustafsson, “<a href="ftp://ftp.isi.edu/in-notes/rfc4701.txt">A DNS Resource Record (RR) for Encoding Dynamic Host Configuration Protocol (DHCP) Information (DHCID RR)</a>,” RFC 4701, October 2006.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4702">[39]</a></td>
<td class="author-text">Stapp, M., Volz, B., and Y. Rekhter, “<a href="ftp://ftp.isi.edu/in-notes/rfc4702.txt">The Dynamic Host Configuration Protocol (DHCP) Client Fully Qualified Domain Name (FQDN) Option</a>,” RFC 4702, October 2006.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4703">[40]</a></td>
<td class="author-text">Stapp, M. and B. Volz, “<a href="ftp://ftp.isi.edu/in-notes/rfc4703.txt">Resolution of Fully Qualified Domain Name (FQDN) Conflicts among Dynamic Host Configuration Protocol (DHCP) Clients</a>,” RFC 4703, October 2006.</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4704">[41]</a></td>
<td class="author-text">Volz, B., “<a href="ftp://ftp.isi.edu/in-notes/rfc4704.txt">The Dynamic Host Configuration Protocol for IPv6 (DHCPv6) Client Fully Qualified Domain Name (FQDN) Option</a>,” RFC 4704, October 2006.</td></tr>
<tr><td class="author-text" valign="top"><a name="draft-failover">[42]</a></td>
<td class="author-text">Droms, R., “<a href="http://www.isc.org/sw/dhcp/drafts/draft-ietf-dhc-failover-12.txt">DHCP Failover Protocol</a>,” March 2003.</td></tr>
</table>
<a name="rfc.authors"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="bug" align="right"><tr><td class="bug"><a href="#toc" class="link2"> TOC </a></td></tr></table>
<h3>Author's Address</h3>
<table width="99%" border="0" cellpadding="0" cellspacing="0">
<tr><td class="author-text"> </td>
<td class="author-text">David W. Hankins</td></tr>
<tr><td class="author-text"> </td>
<td class="author-text">Internet Systems Consortium,
Inc.</td></tr>
<tr><td class="author-text"> </td>
<td class="author-text">950 Charter Street</td></tr>
<tr><td class="author-text"> </td>
<td class="author-text">Redwood City, CA 94063</td></tr>
<tr><td class="author" align="right">Phone: </td>
<td class="author-text">+1 650 423 1300</td></tr>
<tr><td class="author" align="right">Email: </td>
<td class="author-text"><a href="mailto:David_Hankins@isc.org">David_Hankins@isc.org</a></td></tr>
</table>
</body></html>
distrib
>
Mandriva
>
2009.1
>
x86_64
>
media
>
main-testing
>
by-pkgid
>
d66025ce56624bec44a5336810550ff1
>
files
>
4
