273 lines
5.1 KiB
HTML
273 lines
5.1 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<HTML
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><HEAD
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><TITLE
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>Introduction</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK
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REL="HOME"
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TITLE="Linux Mobile IPv6 HOWTO"
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HREF="index.html"><LINK
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REL="PREVIOUS"
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TITLE="Linux Mobile IPv6 HOWTO"
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HREF="index.html"><LINK
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REL="NEXT"
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TITLE="IPv6"
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HREF="ipv6.html"></HEAD
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><BODY
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CLASS="sect1"
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BGCOLOR="#FFFFFF"
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TEXT="#000000"
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LINK="#0000FF"
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VLINK="#840084"
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ALINK="#0000FF"
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><DIV
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CLASS="NAVHEADER"
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><TABLE
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SUMMARY="Header navigation table"
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WIDTH="100%"
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BORDER="0"
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CELLPADDING="0"
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CELLSPACING="0"
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><TR
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><TH
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COLSPAN="3"
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ALIGN="center"
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>Linux Mobile IPv6 HOWTO</TH
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></TR
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><TR
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><TD
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WIDTH="10%"
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ALIGN="left"
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VALIGN="bottom"
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><A
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HREF="index.html"
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ACCESSKEY="P"
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>Prev</A
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></TD
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><TD
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WIDTH="80%"
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ALIGN="center"
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VALIGN="bottom"
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></TD
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><TD
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WIDTH="10%"
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ALIGN="right"
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VALIGN="bottom"
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><A
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HREF="ipv6.html"
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ACCESSKEY="N"
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>Next</A
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></TD
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></TR
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></TABLE
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><HR
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="sect1"
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><H1
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CLASS="sect1"
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><A
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NAME="intro"
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></A
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>1. Introduction</H1
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><P
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> This document describes the software and procedures to set up and
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use mobile IPv6 for Linux. The <A
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HREF="http://www.ietf.org/internet-drafts/draft-ietf-mobileip-ipv6-24.txt"
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TARGET="_top"
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> "Mobility Support in IPv6" draft </A
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> answers the
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<EM
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>what</EM
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> and <EM
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>why</EM
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> of mobile IP:
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</P
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><DIV
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CLASS="sect2"
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><H2
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CLASS="sect2"
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><A
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NAME="WhatisMIPv6"
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></A
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>1.1. What is Mobile IP?</H2
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><P
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> <SPAN
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CLASS="QUOTE"
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>"Each mobile node is always identified by its home
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address, regardless of its current point of attachment to the
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Internet. While situated away from its home, a mobile node is also
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associated with a care-of address, which provides information
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about the mobile node's current location. IPv6 packets addressed
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to a mobile node's home address are transparently routed to its
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care-of address via the mobile nodes Home Agent (HA). The
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protocol enables IPv6 nodes to cache the binding of a mobile
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node's home address with its care-of address, and then to send any
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packets destined for the mobile node directly to it at this
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care-of address."</SPAN
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> --- draft-ietf-mipv6-24, page 1-2.
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</P
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></DIV
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><DIV
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CLASS="sect2"
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><H2
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CLASS="sect2"
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><A
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NAME="WhyMIPv6"
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></A
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>1.2. Why Mobile IP?</H2
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><P
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> <SPAN
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CLASS="QUOTE"
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>"Without specific support for mobility in IPv6, packets destined to a
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mobile node (host or router) would not be able to reach it while the
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mobile node is away from its home link (the link on which its home
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IPv6 subnet prefix is in use), since routing is based on the subnet
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prefix in a packet's destination IP address. In order to continue
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communication in spite of its movement, a mobile node could change its
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IP address each time it moves to a new link, but the mobile node would
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then not be able to maintain transport and higher-layer connections
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when it changes location. Mobility support in IPv6 is particularly
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important, as mobile computers are likely to account for a majority or
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at least a substantial fraction of the population of the Internet
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during the lifetime of IPv6."</SPAN
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> --- draft-ietf-mipv6-24, page 6.
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</P
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><P
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> For all the details, read the <A
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HREF="http://www.ietf.org/internet-drafts/draft-ietf-mobileip-ipv6-24.txt"
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TARGET="_top"
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> "Mobility Support in IPv6" draft</A
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>
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</P
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></DIV
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><DIV
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CLASS="sect2"
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><H2
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CLASS="sect2"
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><A
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NAME="HowWork"
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></A
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>1.3. How does it work?</H2
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><DIV
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CLASS="mediaobject"
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><P
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><IMG
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SRC="images/Mobile-IP.png"
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ALIGN="center"
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WIDTH="520"><DIV
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CLASS="caption"
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><P
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>Mobile IP</P
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></DIV
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></P
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></DIV
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><P
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> <P
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></P
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><OL
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TYPE="1"
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><LI
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><P
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> The Mobile Node (MN) travels to a foreign network and gets a
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new care-of-address.</P
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></LI
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><LI
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><P
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> The MN performs a binding update to its Home Agent (HA) (the
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new care-of-address gets registered at HA). HA sends a binding
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acknowledgement to MN.</P
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></LI
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><LI
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><P
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>A Correspondent Node (CN) wants to contact the MN. The HA
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intercepts packets destined to the MN.</P
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></LI
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><LI
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><P
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>The HA then tunnels all packets to the MN from the CN using
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MN's care-of-address.</P
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></LI
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><LI
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><P
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>When the MN answers the CN, it may use its current
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care-of-address (and perform a binding to the CN) and communicate
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with the CN directly (optimized routing) or it can tunnel all its
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packets through the HA.</P
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></LI
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></OL
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>
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</P
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><P
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>See figure <A
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HREF="intro.html#mobileIP"
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>"Mobile IP"</A
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> for
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an explanation.
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</P
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></DIV
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></DIV
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><DIV
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CLASS="NAVFOOTER"
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><HR
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ALIGN="LEFT"
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WIDTH="100%"><TABLE
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SUMMARY="Footer navigation table"
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WIDTH="100%"
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BORDER="0"
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CELLPADDING="0"
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CELLSPACING="0"
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><TR
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
|
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><A
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HREF="index.html"
|
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ACCESSKEY="P"
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>Prev</A
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></TD
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
|
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><A
|
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HREF="index.html"
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ACCESSKEY="H"
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>Home</A
|
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></TD
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><TD
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WIDTH="33%"
|
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ALIGN="right"
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VALIGN="top"
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><A
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HREF="ipv6.html"
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ACCESSKEY="N"
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>Next</A
|
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></TD
|
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></TR
|
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><TR
|
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><TD
|
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WIDTH="33%"
|
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ALIGN="left"
|
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VALIGN="top"
|
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>Linux Mobile IPv6 HOWTO</TD
|
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><TD
|
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WIDTH="34%"
|
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ALIGN="center"
|
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VALIGN="top"
|
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> </TD
|
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><TD
|
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WIDTH="33%"
|
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ALIGN="right"
|
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VALIGN="top"
|
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>IPv6</TD
|
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></TR
|
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></TABLE
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></DIV
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></BODY
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></HTML
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> |