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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd" []>
<article id="OLSR-IPv6-HOWTO">
<articleinfo>
<!-- Article Title -->
<title>Linux Optimized Link State Routing Protocol (OLSR) IPv6
HOWTO</title>
<titleabbrev>OLSR-IPv6</titleabbrev>
<author>
<firstname>Lars</firstname>
<surname>Strand</surname>
<affiliation>
<!-- Valid email -->
<address><email>lars (at) unik no</email></address>
</affiliation>
</author>
<editor>
<firstname>Emma Jane</firstname>
<surname>Hogbin</surname>
<contrib>Metadata and markup review (1.0)</contrib>
</editor>
<editor>
<firstname>Thomas</firstname>
<surname>Zimmerman</surname>
<contrib>Language review of (0.5)</contrib>
</editor>
<!-- All dates specified in ISO "YYYY-MM-DD" format -->
<pubdate>2004-04-23</pubdate>
<!-- Most recent revision goes at the top; list in descending order -->
<revhistory id="revhistory">
<revision>
<revnumber>1.0</revnumber>
<date>2004-04-23</date>
<authorinitials>EJH</authorinitials>
<revremark>Final review complete. Document published to the LDP
collection.</revremark>
</revision>
<revision>
<revnumber>0.6</revnumber>
<date>2004-04-19</date>
<authorinitials>LKS</authorinitials>
<revremark>Thanks to Thomas Zimmerman &lt;thomas (at) zimres
net> for a language review! Updated to latest version number and
added a section on plugin-support in OLSRd. Changed lisence
back to <ulink
url="http://www.gnu.org/copyleft/fdl.html">GFDL</ulink>
</revremark>
</revision>
<revision>
<revnumber>0.5</revnumber>
<date>2004-03-08</date>
<authorinitials>LKS</authorinitials>
<revremark>An almost complete rewrite. Adding OLSRd (old
uOLSR), updated to RFC3626. Removed NROLSR and
CRCOLSR. Converted to XML Docbook. Changed the license from
<ulink url="http://www.gnu.org/copyleft/fdl.html"> GFDL
</ulink> to <ulink
url="http://www.opencontent.org/openpub/"> OPL </ulink> due
to some GFDL <ulink
url="http://people.debian.org/~srivasta/Position_Statement.xhtml">
problems.</ulink></revremark>
</revision>
<revision>
<revnumber>0.3</revnumber>
<date>2003-08-05</date>
<authorinitials>LKS</authorinitials>
<revremark>Initial release.</revremark>
</revision>
</revhistory>
<!-- Provide a good abstract; a couple of sentences is sufficient -->
<abstract>
<para>
This document describes the software and procedures to set up
and use <ulink url="http://www.ietf.org/rfc/rfc3626">Optimized
Link State Routing Protocol (OLSR)</ulink> with IPv6 for
Linux. OLSR is used as a routing protocol for
Mobile Ad-Hoc Networks (<ulink
url="http://www.ietf.org/rfc/rfc2501.txt">MANET</ulink>) (also
called <quote>spontaneous network</quote>).
</para>
</abstract>
</articleinfo>
<!-- ##################################################### -->
<sect1 id="intro">
<title>Introduction</title>
<para>
This document describes the software and procedures to set up
and use Optimized Link State Routing Protocol (OLSR) with IPv6
for Linux.
</para>
<!-- ################## -->
<sect2 id="WhyAdHoc">
<title>Why Ad-Hoc network?</title>
<para>
An English translation of <emphasis>ad-hoc</emphasis> is <quote>For a
particular purpose (improvised, made up in an instant)</quote>
(source: <ulink
url="http://en.wikipedia.org/wiki/List_of_Latin_phrases#A">Wikipedia</ulink>).
An Ad-hoc network, or <quote>spontaneous network</quote>, is
especially useful when dealing with wireless devices in which some
of the devices are part of the network only for the duration of a
communications session and the need for a dynamic network topology
is eminent. A <quote>Mobile Ad hoc Network</quote> is usually
called a <emphasis>MANET</emphasis>.
</para>
</sect2>
<!-- ################## -->
<sect2 id="WhatMANET">
<title>What is a MANET?</title>
<para><quote>
A MANET consists of mobile platforms (e.g., a router with multiple
hosts and wireless communications devices)--herein simply referred to
as <quote>nodes</quote>--which are free to move about
arbitrarily. The nodes may be located in or on airplanes, ships,
trucks, cars, perhaps even on people or very small devices, and
there may be multiple hosts per router. A MANET is an autonomous
system of mobile nodes. The system may operate in isolation, or
may have gateways to and interface with a fixed network.</quote>
--- <ulink url="http://www.ietf.org/rfc/rfc2501.txt">RFC2501:
Mobile Ad hoc Networking (MANET), section 3 (page 3).</ulink>
</para>
</sect2>
<!-- ################## -->
<sect2 id="WhatOLSR">
<title>What is Optimized Link State Routing (OLSR)?</title>
<para>
<quote>OLSR is a proactive routing protocol for mobile ad hoc
networks. The protocol inherits the stability of a link state
algorithm and has the advantage of having routes immediately
available when needed due to its proactive nature. OLSR is an
optimization over the classical link state protocol, tailored for
mobile ad hoc networks.</quote>
</para>
<para>
<quote>OLSR is designed to work in a completely distributed manner
and does not depend on any central entity. The protocol does NOT
REQUIRE reliable transmission of control messages: each node sends
control messages periodically, and can therefore sustain a
reasonable loss of some such messages. Such losses occur
frequently in radio networks due to collisions or other
transmission problems.</quote> --- <ulink
url="http://www.ietf.org/rfc/rfc3626.txt">RFC3626: OLSR, section
1.3 (page 8)</ulink>
</para>
</sect2>
<!-- ################## -->
<sect2 id="HowOLSR">
<title>How does OLSR work?</title>
<para>
<quote>The Optimized Link State Routing Protocol (OLSR) is
developed for mobile ad hoc networks. It operates as a table
driven, proactive protocol, i.e., exchanges topology information
with other nodes of the network regularly. Each node selects a
set of its neighbor nodes as <quote>multi-point relays</quote>
(MPR). In OLSR, only nodes, selected as such MPRs, are
responsible for forwarding control traffic, intended for diffusion
into the entire network. MPRs provide an efficient mechanism for
flooding control traffic by reducing the number of transmissions
required.</quote> --- <ulink
url="http://www.ietf.org/rfc/rfc3626.txt">RFC3626: OLSR, section
1 (page 4)</ulink>
</para>
</sect2>
<!-- ################## -->
<sect2 id="IBSS">
<title>What about IBSS (IEEE ad-hoc mode)?</title>
<para>The IEEE 802.11 standard defines two modes: </para>
<mediaobject id="ieee">
<imageobject>
<imagedata fileref="images/802-11.png" format="PNG"
width="550" align="center" scalefit="1"/>
</imageobject>
<textobject>
<phrase>801.11</phrase>
</textobject>
<caption>
<para>IEEE 802.11 standard</para>
</caption>
</mediaobject>
<orderedlist>
<listitem>
<para><emphasis>Infrastructure mode:</emphasis> The
wireless network consist of at least one access point (AP)
connected to the wired network and a set of wireless
nodes (WN). This configuration is called a <emphasis>Basic Service Set
(BSS)</emphasis>. Extended Service Set (ESS) is a set of two or
more BSSs (multiple cells).</para>
</listitem>
<listitem>
<para><emphasis>Ad hoc mode:</emphasis> Also called
<quote>IEEE ad-hoc mode</quote> or <quote>peer-to-peer
mode</quote>. This configuration is called
<emphasis>Independent Basic Service Set
(IBSS)</emphasis> and is useful for establishing a
network where wireless infrastructure does not exist or where
services are not required.</para>
</listitem>
</orderedlist>
<para>
So why use OLSR when we can use <quote>IEEE ad-hoc
mode</quote>? <emphasis>IEEE ad-hoc mode does NOT support
multi-hop.</emphasis> See <link linkend="multihop">figure
below</link>
</para>
<mediaobject id="multihop">
<imageobject>
<imagedata fileref="images/multihop.png" format="PNG"
width="550" align="center" scalefit="1"/>
</imageobject>
<textobject>
<phrase>Multihop</phrase>
</textobject>
<caption>
<para><quote>IEEE 8102.11 Ad hoc</quote> mode has
<emphasis>no</emphasis> support for multihop, something OLSR
does have.</para>
</caption>
</mediaobject>
</sect2>
</sect1>
<!-- ##################################################### -->
<sect1 id="IPv6">
<title>IPv6</title>
<para>IP version 6 (IPv6) is a new version of the Internet Protocol,
designed as the successor to IP version 4 (IPv4) <ulink
url="http://www.ietf.org/rfc/rfc791.txt">[RFC-791]</ulink>. The
changes from IPv4 to IPv6 fall primarily into the following
categories:
</para>
<itemizedlist>
<listitem>
<para>Expanded addressing capabilities </para>
</listitem>
<listitem>
<para>Header format simplification</para>
</listitem>
<listitem>
<para>Improved support for extensions and options</para>
</listitem>
<listitem>
<para>Flow labeling capability</para>
</listitem>
<listitem>
<para>Authentication and privacy capabilities</para>
</listitem>
</itemizedlist>
<para>For more information on IPv6 in general, visit the <ulink
url="http://www.ietf.org/html.charters/ipv6-charter.html">IETF's IPv6
Working Group</ulink>.
</para>
</sect1>
<!-- ####################################################### -->
<sect1 id="OLSRLinux">
<title>OLSR for Linux</title>
<para>
There are several OLSR implementation for Linux, but not all of them
support IPv6. You should know how to enable and use IPv6
on Linux. Peter Bieringer has written an excellent <ulink
url="http://ldp.linux.no/HOWTO/Linux+IPv6-HOWTO/">Linux IPv6
HOWTO</ulink>.
</para>
<para>
There is one OLSR implementation that is becoming the
<quote>standard</quote> and most widely used. It goes by the
descriptive name <quote>OLSRd</quote> (old Unik-OLSR).
</para>
<para>
OLSRd is an implementation based on the INRA C code, but has been
almost completely rewritten, so there is not much left of the original
INRA code (that mean it almost GPL). OLSRd also is under very rapid
development, and if you report in a bug, it is usually fixed in a
matter of hours.
</para>
<para>
OLSRd <ulink
url="http://www.olsr.org/index.cgi?action=comp">fully comply</ulink>
to the OLSR RFC, support for plugins, and it has an optional GUI
interface (to see what's going on). The implementation also has a
informative <quote>up-to-date</quote> <ulink
url="http://www.olsr.org">web-page</ulink> with links to mailing
lists and papers.
</para>
<!-- ################## -->
<sect2 id="installing">
<title>Installing OLSRd</title>
<para>There are up-to multiple new releases of OLSRd each month, so
check the OLSRd <ulink url="http://www.olsr.org">web-site</ulink>
for the newest release.</para>
<para>
<orderedlist>
<listitem>
<para> The latest release as of this writing is 0.4.3, but by the
time you read this there is almost certain a new release. Fetch the
latest release from <ulink
url="http://www.olsr.org/index.cgi?action=download">
http://www.olsr.org/index.cgi?action=download</ulink>.</para>
</listitem>
<listitem>
<para>Unpack, compile and install the source code:</para>
<programlisting>
<prompt># </prompt><userinput><command>tar</command> jxvf uolsrd-x.y.z</userinput>
<prompt># </prompt><userinput><command>cd</command> unik-olsrd-x.y.z</userinput>
<prompt># </prompt><userinput><command>make</command></userinput>
<prompt># </prompt><userinput><command>make install</command></userinput>
</programlisting>
</listitem>
<listitem>
<para>The <userinput>olsrd</userinput> gets installed to
<filename class='directory'>/usr/bin/</filename> and a default config file,
<filename>olsrd.conf</filename> can be found under
<filename class="directory">/etc</filename></para>
</listitem>
</orderedlist>
</para>
<para>Check out the <filename>/etc/olsrd.conf</filename> config
file, and change values to fit your system. All values in this file
can be overridden with command line options to
<userinput>olsrd</userinput>. The main options to change are:</para>
<para>
<screen>
# Debug level(0-9)
# If set to 0 the daemon runs in the background
DEBUG 1
# IP version to use (4 or 6)
IPVERSION 6
# A list of whitespace separated interface names
INTERFACES eth1
</screen>
</para>
<para>
Later on, when you know OLSRd is configured correctly, you may set
<quote>DEBUG</quote> to <userinput>0</userinput> to make it run in
the background. You may then also add it to your init scripts. But
to test that everything first, set this to at least
<userinput>1</userinput> (setting this higher will produce a lot
more info messages on APM, forwarding, parsing of the config file
etc.)
</para>
</sect2>
<!-- ################## -->
<sect2 id="using">
<title>Using OLSRd</title>
<!-- ######### -->
<sect3 id="onehost">
<title>On one host</title>
<para>When OLSRd is installed and configured, it can be started
as root with:</para>
<programlisting>
<prompt># </prompt><userinput><command>olsrd</command></userinput>
</programlisting>
<para>All the settings in <filename>/etc/olsrd.conf</filename>
can be overridden by command line options:</para>
<programlisting>
<prompt># </prompt><userinput><command>olsrd</command> -i eth1 -ipv6 -d 1</userinput>
</programlisting>
<para>Would start <userinput>olsrd</userinput> listening on
interface <userinput>eth1</userinput> using IPv6 and with debug
messages.</para>
<para>We start olsrd:</para>
<screen>
<prompt># </prompt><userinput><command>olsrd</command> -i eth1 -d 1 -ipv6</userinput>
*** UniK olsrd-0.4.3 ***
hello interval = 2.00 hello int nonwireless: = 4.00 <co id="tuning"/>
tc interval = 5.00 polling interval = 0.10
neighbor_hold_time = 6.00 neighbor_hold_time_nw = 12.00
topology_hold_time = 15.00 tos setting = 16
hna_interval = 15.00 mid_interval = 5.00
Willingness set to 3 - next update in 20.000000 secs
Using IP version 6
Using multicast address ff05::15
---- Interface configuration ----
eth1: <co id="interface"/>
Address: fec0:106:2700::10
Multicast: ff05::15
Interface eth1 set up for use with index 0
Main address: fec0:106:2700::10 <co id="adr"/>
NEIGHBORS: l=linkstate, m=MPR, w=willingness
Thread created - polling every 0.10 seconds <co id="list"/>
neighbor list: 11:43:17.214807
neighbor list: 11:43:19.194967
neighbor list: 11:43:21.395046
neighbor list: 11:43:23.604800
neighbor list: 11:43:25.694875
</screen>
<calloutlist>
<callout arearefs="tuning">
<para>This shows all the settings OLSRd is using. You may
override these by either specifying it in the config file
(<filename>/etc/olsrd.conf</filename>) or specify it at the
command line. Read the <ulink
url="http://www.ietf.org/rfc/rfc3626.txt">OLSR RFC</ulink> for a
description on what all these settings means.</para>
</callout>
<callout arearefs="interface">
<para>OLSRd found our interface. If you are using OLSRd with
multiple interfaces, <quote>Multiple Interface
Declaration</quote> (MID) messages will be generated.</para>
</callout>
<callout arearefs="adr">
<para>If you are using OLSRd with multiple interfaces, it will
pick the first interface specified as the <quote>main</quote>
address.</para>
</callout>
<callout arearefs="list">
<para>Since no other hosts are running OLSRd, this list is
empty.</para>
</callout>
</calloutlist>
<para>Another thing worth noticing, is that an entry is added to
our routing table:</para>
<screen>
<prompt>#</prompt> <userinput><command>route</command> -A inet6</userinput>
Destination: Next Hop Flags Metric Ref Use Iface
...
ff05::15/128 ff05::15 UAC 0 1 1 eth1
...
</screen>
<para>This is the IPv6 multicast address OLSR is using to talk to
other nodes running OLSR.</para>
</sect3>
<!-- ######### -->
<sect3 id="addhosts">
<title>Adding other hosts</title>
<para>There is no point in using OLSRd on only one node, so we add
some nodes. You will then see the <quote>neighbor list</quote> gets
updated:</para>
<screen>
neighbor list: 12:55:14.733586
neighbor list: 12:55:18.803585
Willingness for fec0:106:2700::11 changed from 0 to 3 - UPDATING <co id="will"/>
neighbor list: 12:55:22.763585
fec0:106:2700::11:l=0:m=0:w=3[2hlist:] <co id="newhost"/>
neighbor list: 12:55:26.833589
fec0:106:2700::11:l=1:m=0:w=3[2hlist:]
Willingness for fec0:106:2700::12 changed from 0 to 2 - UPDATING <co id="thirdhost"/>
neighbor list: 12:55:30.903585
fec0:106:2700::12:l=0:m=0:w=2[2hlist:]
fec0:106:2700::11:l=1:m=0:w=3[2hlist:]
neighbor list: 12:55:34.863585
fec0:106:2700::12:l=0:m=0:w=2[2hlist:]
fec0:106:2700::11:l=1:m=0:w=3[2hlist:]
neighbor list: 12:55:39.153586
fec0:106:2700::12:l=1:m=0:w=2[2hlist:fec0:106:2700::11:] <co id="triangle"/>
fec0:106:2700::11:l=1:m=0:w=3[2hlist:fec0:106:2700::12:] <co id="triangle2"/>
neighbor list: 12:55:43.443605
fec0:106:2700::12:l=1:m=0:w=2[2hlist:fec0:106:2700::11:]
fec0:106:2700::11:l=1:m=0:w=3[2hlist:fec0:106:2700::12:]
</screen>
<calloutlist>
<callout arearefs="will">
<para>
Another node detected (node B). This specifies the willingness of a node
to carry and forward traffic for other nodes. Here the new node
<userinput>fec0:106:2700::11</userinput> is willing to forward
traffic. A host with low battery may not be willing to forward
large amount of traffic, - so it will proclaim a lower
willingness value (routing based on powerstatus is available as a
plugin).
</para>
</callout>
<callout arearefs="newhost">
<para>
The node has been added to our routing table. We can not (yet)
reach any other node by way of this node, since the 2-hop neighbor
list (<userinput>[2hlist:]</userinput>) is empty. A 2-hop
neighbor is a node heard by a neighbor.
</para>
</callout>
<callout arearefs="thirdhost">
<para>
Here is a third node (node C) running OLSRd.
</para>
</callout>
<callout arearefs="triangle">
<para>
After a short time, when all nodes have been updated and routes
calculated, we may also reach any of the other nodes via the
other. The 2-hop neighbor list
(<userinput>[2hlist:]</userinput>) is populated: We can reach node
<userinput> B</userinput> via <userinput>C</userinput>.
</para>
</callout>
<callout arearefs="triangle2">
<para>
Here we can reach node <userinput>C</userinput> via
<userinput>B</userinput>.
</para>
</callout>
</calloutlist>
<para>You will also see the routing table is updated with the new
hosts:</para>
<screen>
<prompt>#</prompt> <userinput><command>route</command> -A inet6</userinput>
Destination: Next Hop Flags Metric Ref Use Iface
...
fec0:106:2700::11/128 :: UH 1 0 0 eth1
fec0:106:2700::12/128 :: UH 1 0 0 eth1
...
</screen>
<para>
The real beauty of OLSR is when you add a bunch of nodes and move
them around. You can still reach each one of them either directly
(if they are close), or through other nodes.
</para>
</sect3>
<!-- ######### -->
<sect3 id="movement">
<title>Movement</title>
<para>
When every node can reach every other node, it's no fun. Let's
start moving the nodes, so that node <quote>A</quote> and
<quote>B</quote> are out of (radio) range of each other. So when
we move node <quote>A</quote> far enough away so that
it can't hear node <quote>C</quote>, all traffic must go through
node <quote>B</quote>: </para>
<mediaobject id="moving">
<imageobject>
<imagedata fileref="images/movement.png" format="PNG"
width="450" align="center" scalefit="1"/>
</imageobject>
<textobject>
<phrase>Movement</phrase>
</textobject>
<caption>
<para>We move our three nodes so that node
<userinput>A</userinput> and <userinput>C</userinput> must
speak through node <userinput>B</userinput> to reach each
other.
</para>
</caption>
</mediaobject>
<para>
Tip: Instead of physically moving the nodes around, you can use
<userinput>ip6tables</userinput>. You can drop all packet using the
MAC-address. You just need to block on one node:
</para>
<screen>
<prompt># </prompt><userinput><command>ip6tables</command> -A INPUT -m mac --mac-source XX:XX:XX:XX:XX:XX -j DROP</userinput>
</screen>
<para>
The output from OLSRd on host A is then:
</para>
<screen>
neighbor list: 13:22:35.693587
fec0:106:2700::11:l=1:m=1:w=3[2hlist:fec0:106:2700::12:] <co id="onlyone"/>
neighbor list: 13:22:40.093588
fec0:106:2700::11:l=1:m=1:w=3[2hlist:fec0:106:2700::12:]
neighbor list: 13:22:44.053594
fec0:106:2700::11:l=1:m=1:w=3[2hlist:fec0:106:2700::12:]
neighbor list: 13:22:48.233594
fec0:106:2700::11:l=1:m=1:w=3[2hlist:fec0:106:2700::12:]
neighbor list: 13:22:52.193605
fec0:106:2700::11:l=1:m=1:w=3[2hlist:fec0:106:2700::12:]
</screen>
<calloutlist>
<callout arearefs="onlyone">
<para>
We can reach node <userinput>B</userinput> directly, and via node
<userinput>B</userinput> we can reach node <userinput>C</userinput>.
</para>
</callout>
</calloutlist>
<para>
The routing table also gets updated. For node
<userinput>A</userinput> to reach node <userinput>C</userinput> it
must go through node <userinput>B</userinput>:</para>
<screen>
<prompt>#</prompt> <userinput><command>route</command> -A inet6</userinput>
Destination: Next Hop Flags Metric Ref Use Iface
...
fec0:106:2700::11/128 :: UH 1 1 0 eth1
fec0:106:2700::12/128 fec0:106:2700::11 UGH 2 0 0 eth1
...
</screen>
</sect3>
</sect2>
<!-- ################## -->
<sect2 id="hna">
<title>What about HNA messages?</title>
<para><quote>
In order to provide this capability of injecting external routing
information into an OLSR MANET, a node with such non-MANET interfaces
periodically issues a Host and Network Association (HNA) message,
containing sufficient information for the recipients to construct an
appropriate routing table.</quote>
</para>
<para><quote>
An example of such a situation could be where a node is equipped with
a fixed network (e.g., an Ethernet) connecting to a larger network as
well as a wireless network interface running OLSR.</quote> --- <ulink
url="http://www.ietf.org/rfc/rfc2501.txt">RFC3626: OLSR, section
12 (page 51).</ulink>
</para>
<mediaobject id="HNA">
<imageobject>
<imagedata fileref="images/HNA.png" format="PNG"
width="550" align="center" scalefit="1"/>
</imageobject>
<textobject>
<phrase>HNA</phrase>
</textobject>
<caption>
<para>OLSR with a gateway (GW), that sends out HNA messages. All
the other nodes may then be accessing the
<quote>Internet</quote></para>
</caption>
</mediaobject>
<para>
To have one node, act as a gateway and send out HNA messages, you
must change the <userinput>HNA6</userinput> in
<filename>/etc/olsrd.conf</filename>:
</para>
<screen>
# HNA IPv6 routes
# syntax: netaddr prefix
# Example Internet gateway
HNA6 :: 0
</screen>
<para>
When you start <userinput>OLSRd</userinput>, you will see the node
is sending out HNA messages periodically:</para>
<screen>
...
Sending HNA (48 bytes)...
...
</screen>
<para>
When the other nodes receives a HNA message, they update their
routing table:
</para>
<screen>
<prompt>#</prompt> <userinput><command>route</command> -A inet6</userinput>
Destination: Next Hop Flags Metric Ref Use Iface
...
::/0 fec0:106:2700::1 UG 1 0 0 eth1
...
</screen>
<para>
You may also have multiple nodes in a MANET to act as gateways
(sending out HNA messages). Each mobile node then use the nearest
gateway.
</para>
</sect2>
<!-- ################## -->
<sect2 id="plugins">
<title>Plugin support</title>
<para>As of version 0.4.3 OLSRd also support plugins. Plugins may be
used to add extended functionality in a MANET. If only a subset of
the nodes knows how to interpret the messagetype, it will be
forwarded by all the nodes by the <quote>default forwarding
algorithm</quote>
(see section 3.4.1 in the <ulink
url="http://ietf.org/rfc/rfc3626.txt">OLSR RFC</ulink>). This way
certain nodes may add special functionlity into OLSR.</para>
<para>As of this writing, two example plugins is included in the
OLSRd release. One of these plugins add routing based on
powerstatus. If one node has low battery, it can set its willingness
lower and traffic may be routed through other nodes.</para>
</sect2>
<!-- ################## -->
<sect2 id="gui">
<title>Optional GUI</title>
<para>
OLSRd also has an optional GUI, which can show a list of
available nodes and grab packets. To compile the GUI front end,
you must have GTK2. In <filename
class="directory">unik-olsrd-x.y.z</filename>
directory do:
</para>
<screen>
<prompt>#</prompt> <userinput><command>cd</command> front-end</userinput>
<prompt>#</prompt> <userinput><command>make</command></userinput>
<prompt>#</prompt> <userinput><command>make</command> install</userinput>
</screen>
<note><para>
Remember to start OLSRd with the
<userinput>-ipc</userinput> switch or set
<userinput>IPC-CONNECT yes</userinput> in
<userinput>/etc/olsrd.conf</userinput> to enable the GUI to chat
with OLSRd.
</para></note>
<para>
To see some examples of the use of GUI, check out <ulink
url="http://www.olsr.org/index.cgi?action=gui">
http://www.olsr.org/index.cgi?action=gui</ulink>
</para>
</sect2>
<!-- ################## -->
<sect2 id="other">
<title>Other OLSR implementations</title>
<para>There is also other OLSR implementations, none have gained as
much popularity as OLSRd, and none of them (except <ulink
url="http://qolsr.lri.fr/">QOLSR</ulink>?) are fully RFC
compliant.</para>
<!-- ######### -->
<sect3 id="inria">
<title>INRIA</title>
<para>INRIA was one of the first(?) implementation of OLSR <ulink
url="http://hipercom.inria.fr/olsr/#code">http://hipercom.inria.fr/olsr/#code</ulink>.
Their web-site has not been updated for quite a while, and the
OLSR code you can download only complies to
draft-ietf-manet-olsr-03.txt (it's now an RFC). There is suppose to
be another more up-to-date version of INRIA olsr, but I have not
found it. INRIA OLSR does not support IPv6.</para>
</sect3>
<!-- ######### -->
<sect3 id="nr">
<title>NROLSR</title>
<para>The <quote>US Naval Research Laboratory</quote> (NRL) also
has an OLSR implementation. It is written in C++, and has IPv6
support. <ulink url="http://pf.itd.nrl.navy.mil/projects/olsr/">
http://pf.itd.nrl.navy.mil/projects/olsr/</ulink>
</para>
</sect3>
<!-- ######### -->
<sect3 id="crc">
<title>CRCOLSR</title>
<para>CRCOLSR is a implementation based on the French INRIA
code. It is is supposed to be maintained by <quote>Communication
Research Center</quote> (CRC) in Canada. But as of this writing,
there have been no new releases since April 3, 2003. <ulink
url="http://pf.itd.nrl.navy.mil/projects/olsr/">
http://pf.itd.nrl.navy.mil/projects/olsr/</ulink></para>
</sect3>
<!-- ######### -->
<sect3 id="qolsr">
<title>QOLSR</title>
<para>QOLSR is aiming to provide <quote>Quality of
Service</quote> routing in wireless mobile ad hoc
networks. There is no QoS support at the time of this writing,
and support for ipv4/ipv6 is triggered at compile time. Written
in C++.</para>
</sect3>
</sect2>
</sect1>
<!-- ##################################################### -->
<sect1 id="faq">
<title>FAQ</title>
<para>Some of these question/answers are from the <ulink
url="http://www.olsr.org">OLSRd</ulink> site.</para>
<qandaset>
<qandaentry>
<question>
<para>If OLSRd fully RFC3626 compliant?</para>
</question>
<answer>
<para>Yes. It even has implemented some of the extra
functionality mentioned in the RFC. See the <ulink
url="http://www.olsr.org/index.cgi?action=comp">
RFC Compliance</ulink> section for complete list.
</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>Can I mix site-local and global IPv6 addresses?</para>
</question>
<answer>
<para>Yes. But keep in mind that they intentionally were not
designed to be used at the same time. The network topology can be
quite <quote>messy</quote> if you start using these two.
</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>The GUI front-end failed to compile...why?</para>
</question>
<answer>
<para>You probably don't have the GTK2.0 development libraries
installed.</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>If there is multiply gateways present, how does
the mobile node conclude to use the nearest one?</para>
</question>
<answer>
<para>When a new gateway is detected, the Mobile Node checks the
distance (number of hops) to this newly discovered gateway
compared to the current gateway. If there is a shorter distance,
this new gateway becomes the current (default) gateway. See
section 12.6.2 in the OLSR RFC (<ulink
url="http://www.ietf.org/rfc/rfc3626.txt">RFC3626</ulink>)</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>I get OLSRd up and running - but the nodes
don't seem to <quote>hear</quote> each other!</para>
</question>
<answer>
<para>Most of the time this is a configuration error: Check
the following:</para>
<itemizedlist>
<listitem><para>
If using WLAN interfaces make sure the ESSID/key match.
</para></listitem>
<listitem><para>
Make sure the cards are set in <quote>ad-hoc</quote> mode
and not <quote>managed</quote>.
</para></listitem>
<listitem><para>
Make sure you are not blocking UDP/698. If using
netfilter run <userinput>ip6tables -L</userinput> as root
to see what rules are set. <userinput>ip6tables
-F</userinput> flushes all rules.
</para></listitem>
</itemizedlist>
</answer>
</qandaentry>
</qandaset>
</sect1>
<!-- ##################################################### -->
<sect1 id="resources">
<title>Useful Resources</title>
<para>
<orderedlist>
<listitem>
<para>OLSRd (old uOLSR)<ulink
url="http://www.olsr.org">
http://www.olsr.org</ulink>
</para>
</listitem>
<listitem>
<para>Optimized Link State Routing Protocol (OLSR) RFC3626<ulink
url="http://www.ietf.org/rfc/rfc3626.txt">
http://www.ietf.org/rfc/rfc3626.txt</ulink>
</para>
</listitem>
<listitem>
<para>Mobile Ad hoc Networking (MANET) RFC2501<ulink
url="http://www.ietf.org/rfc/rfc2501.txt">
http://www.ietf.org/rfc/rfc3626.txt</ulink>
</para>
</listitem>
<listitem>
<para>Mobile Ad-hoc Networks (manet) Working Group (IETF)<ulink
url="http://www.ietf.org/html.charters/manet-charter.html">
http://www.ietf.org/html.charters/manet-charter.html</ulink>
</para>
</listitem>
<listitem>
<para>Open Shortest Path First IGP (ospf)<ulink
url="http://www.ietf.org/html.charters/ospf-charter.html">
http://www.ietf.org/html.charters/ospf-charter.html</ulink>
</para>
</listitem>
<listitem>
<para>Protean Forge - OLSR software (CRC and NRL) <ulink
url="http://pf.itd.nrl.navy.mil/projects/olsr/">
http://pf.itd.nrl.navy.mil/projects/olsr/</ulink></para>
</listitem>
<listitem>
<para>INRIA OLSR <ulink
url="http://hipercom.inria.fr/olsr/">
http://hipercom.inria.fr/olsr/</ulink></para>
</listitem>
<listitem>
<para>QOLSR <ulink
url="http://qolsr.lri.fr/">
http://qolsr.lri.fr/</ulink></para>
</listitem>
<listitem>
<para>IPv6 Working Group (IETF) <ulink
url="http://www.ietf.org/html.charters/ipv6-charter.html">
http://www.ietf.org/html.charters/ipv6-charter.html </ulink></para>
</listitem>
<listitem>
<para>RFC2460 Internet Protocol, Version 6 (IPv6) Specification
<ulink url="http://www.ietf.org/rfc/rfc2460.txt">
http://www.ietf.org/rfc/rfc2460.txt </ulink></para>
</listitem>
<listitem>
<para>Peter Bieringer's Linux IPv6 HOWTO (en) <ulink
url="http://ldp.linux.no/HOWTO/Linux+IPv6-HOWTO/">
http://ldp.linux.no/HOWTO/Linux+IPv6-HOWTO/ </ulink></para>
</listitem>
<listitem>
<para>Current Status of IPv6 Support for Networking Applications
<ulink url="http://www.deepspace6.net/docs/ipv6_status_page_apps.html">
http://www.deepspace6.net/docs/ipv6_status_page_apps.html</ulink></para>
</listitem>
</orderedlist>
</para>
</sect1>
<!-- ##################################################### -->
<sect1 id="copyack">
<title>Copyright, acknowledgments and miscellaneous</title>
<!-- ################## -->
<sect2 id="copyright">
<title>Copyright and License</title>
<para> Copyright (c) 2003, 2004 Lars Strand.</para>
<para>
Permission is granted to copy, distribute and/or modify this
document under the terms of the <ulink
url="http://www.gnu.org/licenses/fdl.html">GNU Free
Documentation License</ulink>, Version 1.2 or any later version
published by the Free Software Foundation; with no Invariant
Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy
of the license is included in the section entitled "GNU Free
Documentation License".
</para>
</sect2>
<!-- ################## -->
<sect2 id="produced">
<title>How this document was produced</title>
<para>This document was originally written in LaTeX using
Emacs. HTML version created with latex2html. Later it was
converted to DocBook XML.</para>
<para>An up-to-date version of this document can be found at:</para>
<para> HTML: <ulink url="http://www.tldp.org/HOWTO/OLSR-IPv6-HOWTO/index.html">
http://www.tldp.org/HOWTO/OLSR-IPv6-HOWTO/index.html</ulink> </para>
</sect2>
<!-- ################## -->
<sect2 id="feedback">
<title>Feedback</title>
<para>Suggestions, corrections, additions wanted. Contributors
wanted and acknowledged. Flames not wanted.</para>
<para>I can always be reached at <email>lars at unik
no</email></para>
<para>Homepage: <ulink
url="http://www.gnist.org/~lars/">
http://www.gnist.org/~lars/</ulink></para>
</sect2>
<!-- ################## -->
<sect2 id="ack">
<title>Acknowledgments</title>
<para>This document was produced as a part of Interoperable
Networks for Secure Communications <ulink
url="http://insc.nodeca.mil.no/">(INSC task 6)</ulink></para>
<para>Thanks to Andreas Hafslund (andreha [at] unik no) for
initial support. Also thanks to UniK (University Graduate Center)
<ulink url="http://www.unik.no">http://www.unik.no</ulink> and FFI
(Norwegian Defence Research Establishment) <ulink
url="http://www.ffi.mil.no">http://www.ffi.mil.no</ulink> for
hardware support.</para>
<para>Also thanks to Andreas T&#248;nnesen (andreto [at] unik no) for
technical help updating this howto</para>
<para>Thanks also to the other HOWTO authors whose works I have
referenced: </para>
<para><emphasis>Linux IPv6 HOWTO (en)</emphasis> by Peter
Bieringer</para>
</sect2>
</sect1>
<!-- ################## -->
<appendix id="gfdl">
<title>GNU Free Documentation License</title>
<subtitle>Version 1.2, November 2002</subtitle>
<blockquote id="fsf-copyright">
<para>Copyright (C) 2000,2001,2002 Free Software Foundation, Inc.
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copy. If there are multiple Invariant Sections with the same name but
different contents, make the title of each such section unique by adding
at the end of it, in parentheses, the name of the original author or
publisher of that section if known, or else a unique number. Make the
same adjustment to the section titles in the list of Invariant Sections
in the license notice of the combined work.</para>
<para>In the combination, you must combine any sections Entitled
"History" in the various original documents, forming one section
Entitled "History"; likewise combine any sections Entitled
"Acknowledgements", and any sections Entitled "Dedications". You must
delete all sections Entitled "Endorsements".</para>
</section>
<section id="gfdl-6"><title>COLLECTIONS OF DOCUMENTS</title>
<para>You may make a collection consisting of the Document and other
documents released under this License, and replace the individual copies
of this License in the various documents with a single copy that is
included in the collection, provided that you follow the rules of this
License for verbatim copying of each of the documents in all other
respects.</para>
<para>You may extract a single document from such a collection, and
distribute it individually under this License, provided you insert a
copy of this License into the extracted document, and follow this
License in all other respects regarding verbatim copying of that
document.</para>
</section>
<section id="gfdl-7"><title>AGGREGATION WITH INDEPENDENT WORKS</title>
<para>A compilation of the Document or its derivatives with other
separate and independent documents or works, in or on a volume of a
storage or distribution medium, is called an "aggregate" if the
copyright resulting from the compilation is not used to limit the legal
rights of the compilation's users beyond what the individual works
permit. When the Document is included in an aggregate, this License does
not apply to the other works in the aggregate which are not themselves
derivative works of the Document.</para>
<para>If the Cover Text requirement of section 3 is applicable to these
copies of the Document, then if the Document is less than one half of
the entire aggregate, the Document's Cover Texts may be placed on covers
that bracket the Document within the aggregate, or the electronic
equivalent of covers if the Document is in electronic form. Otherwise
they must appear on printed covers that bracket the whole
aggregate.</para>
</section>
<section id="gfdl-8"><title>TRANSLATION</title>
<para>Translation is considered a kind of modification, so you may
distribute translations of the Document under the terms of section 4.
Replacing Invariant Sections with translations requires special
permission from their copyright holders, but you may include
translations of some or all Invariant Sections in addition to the
original versions of these Invariant Sections. You may include a
translation of this License, and all the license notices in the
Document, and any Warranty Disclaimers, provided that you also include
the original English version of this License and the original versions
of those notices and disclaimers. In case of a disagreement between the
translation and the original version of this License or a notice or
disclaimer, the original version will prevail.</para>
<para>If a section in the Document is Entitled "Acknowledgements",
"Dedications", or "History", the requirement (section 4) to Preserve its
Title (section 1) will typically require changing the actual
title.</para>
</section>
<section id="gfdl-9"><title>TERMINATION</title>
<para>You may not copy, modify, sublicense, or distribute the Document
except as expressly provided for under this License. Any other attempt
to copy, modify, sublicense or distribute the Document is void, and will
automatically terminate your rights under this License. However,
parties who have received copies, or rights, from you under this License
will not have their licenses terminated so long as such parties remain
in full compliance.</para>
</section>
<section id="gfdl-10"><title>FUTURE REVISIONS OF THIS LICENSE</title>
<para>The Free Software Foundation may publish new, revised versions of
the GNU Free Documentation License from time to time. Such new versions
will be similar in spirit to the present version, but may differ in
detail to address new problems or concerns. See
http://www.gnu.org/copyleft/.</para>
<para>Each version of the License is given a distinguishing version
number. If the Document specifies that a particular numbered version of
this License "or any later version" applies to it, you have the option
of following the terms and conditions either of that specified version
or of any later version that has been published (not as a draft) by the
Free Software Foundation. If the Document does not specify a version
number of this License, you may choose any version ever published (not
as a draft) by the Free Software Foundation.</para>
</section>
<section id="gfdl-addendum"><title>ADDENDUM: How to use this License for
your documents</title>
<para>To use this License in a document you have written, include a copy
of the License in the document and put the following copyright and
license notices just after the title page:</para>
<blockquote id="copyright-sample"><para>
Copyright (c) YEAR YOUR NAME.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.2
or any later version published by the Free Software Foundation;
with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
A copy of the license is included in the section entitled "GNU
Free Documentation License".
</para></blockquote>
<para>If you have Invariant Sections, Front-Cover Texts and Back-Cover
Texts, replace the "with...Texts." line with this:</para>
<blockquote id="inv-cover-sample"><para>
with the Invariant Sections being LIST THEIR TITLES, with the
Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
</para></blockquote>
<para>If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation.</para>
<para>If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of free
software license, such as the GNU General Public License, to permit
their use in free software.</para>
</section>
</appendix>
</article>
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