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  13  <h1>
  14      <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
  15
  16  </h1>
  17
  18 </div>
  19
  20
  21     <h3>Entries tagged "mesh network".</h3>
  22
  23     <div class="entry">
  24       <div class="title">
  25         <a href="http://people.skolelinux.org/pere/blog/Teaching_vmdebootstrap_to_create_Raspberry_Pi_SD_card_images.html">Teaching vmdebootstrap to create Raspberry Pi SD card images</a>
  26       </div>
  27       <div class="date">
  28         27th October 2013
  29       </div>
  30       <div class="body">
  31         <p>The
  32 <a href="http://packages.qa.debian.org/v/vmdebootstrap.html">vmdebootstrap</a>
  33 program is a a very nice system to create virtual machine images.  It
  34 create a image file, add a partition table, mount it and run
  35 debootstrap in the mounted directory to create a Debian system on a
  36 stick.  Yesterday, I decided to try to teach it how to make images for
  37 <a href="https://wiki.debian.org/RaspberryPi">Raspberry Pi</a>, as part
  38 of a plan to simplify the build system for
  39 <a href="https://wiki.debian.org/FreedomBox">the FreedomBox
  40 project</a>.  The FreedomBox project already uses vmdebootstrap for
  41 the virtualbox images, but its current build system made multistrap
  42 based system for Dreamplug images, and it is lacking support for
  43 Raspberry Pi.</p>
  44
  45 <p>Armed with the knowledge on how to build "foreign" (aka non-native
  46 architecture) chroots for Raspberry Pi, I dived into the vmdebootstrap
  47 code and adjusted it to be able to build armel images on my amd64
  48 Debian laptop.  I ended up giving vmdebootstrap five new options,
  49 allowing me to replicate the image creation process I use to make
  50 <a href="http://people.skolelinux.org/pere/blog/A_Raspberry_Pi_based_batman_adv_Mesh_network_node.html">Debian
  51 Jessie based mesh node images for the Raspberry Pi</a>.  First, the
  52 <tt>--foreign /path/to/binfm_handler</tt> option tell vmdebootstrap to
  53 call debootstrap with --foreign and to copy the handler into the
  54 generated chroot before running the second stage.  This allow
  55 vmdebootstrap to create armel images on an amd64 host.  Next I added
  56 two new options <tt>--bootsize size</tt> and <tt>--boottype
  57 fstype</tt> to teach it to create a separate /boot/ partition with the
  58 given file system type, allowing me to create an image with a vfat
  59 partition for the /boot/ stuff.  I also added a <tt>--variant
  60 variant</tt> option to allow me to create smaller images without the
  61 Debian base system packages installed.  Finally, I added an option
  62 <tt>--no-extlinux</tt> to tell vmdebootstrap to not install extlinux
  63 as a boot loader.  It is not needed on the Raspberry Pi and probably
  64 most other non-x86 architectures.  The changes were accepted by the
  65 upstream author of vmdebootstrap yesterday and today, and is now
  66 available from
  67 <a href="http://git.liw.fi/cgi-bin/cgit/cgit.cgi/vmdebootstrap/">the
  68 upstream project page</a>.</p>
  69
  70 <p>To use it to build a Raspberry Pi image using Debian Jessie, first
  71 create a small script (the customize script) to add the non-free
  72 binary blob needed to boot the Raspberry Pi and the APT source
  73 list:</p>
  74
  75 <p><pre>
  76 #!/bin/sh
  77 set -e # Exit on first error
  78 rootdir="$1"
  79 cd "$rootdir"
  80 cat &lt;&lt;EOF > etc/apt/sources.list
  81 deb http://http.debian.net/debian/ jessie main contrib non-free
  82 EOF
  83 # Install non-free binary blob needed to boot Raspberry Pi.  This
  84 # install a kernel somewhere too.
  85 wget https://raw.github.com/Hexxeh/rpi-update/master/rpi-update \
  86     -O $rootdir/usr/bin/rpi-update
  87 chmod a+x $rootdir/usr/bin/rpi-update
  88 mkdir -p $rootdir/lib/modules
  89 touch $rootdir/boot/start.elf
  90 chroot $rootdir rpi-update
  91 </pre></p>
  92
  93 <p>Next, fetch the latest vmdebootstrap script and call it like this
  94 to build the image:</p>
  95
  96 <pre>
  97 sudo ./vmdebootstrap \
  98     --variant minbase \
  99     --arch armel \
 100     --distribution jessie \
 101     --mirror http://http.debian.net/debian \
 102     --image test.img \
 103     --size 600M \
 104     --bootsize 64M \
 105     --boottype vfat \
 106     --log-level debug \
 107     --verbose \
 108     --no-kernel \
 109     --no-extlinux \
 110     --root-password raspberry \
 111     --hostname raspberrypi \
 112     --foreign /usr/bin/qemu-arm-static \
 113     --customize `pwd`/customize \
 114     --package netbase \
 115     --package git-core \
 116     --package binutils \
 117     --package ca-certificates \
 118     --package wget \
 119     --package kmod
 120 </pre></p>
 121
 122 <p>The list of packages being installed are the ones needed by
 123 rpi-update to make the image bootable on the Raspberry Pi, with the
 124 exception of netbase, which is needed by debootstrap to find
 125 /etc/hosts with the minbase variant.  I really wish there was a way to
 126 set up an Raspberry Pi using only packages in the Debian archive, but
 127 that is not possible as far as I know, because it boots from the GPU
 128 using a non-free binary blob.</p>
 129
 130 <p>The build host need debootstrap, kpartx and qemu-user-static and
 131 probably a few others installed.  I have not checked the complete
 132 build dependency list.</p>
 133
 134 <p>The resulting image will not use the hardware floating point unit
 135 on the Raspberry PI, because the armel architecture in Debian is not
 136 optimized for that use.  So the images created will be a bit slower
 137 than <a href="http://www.raspbian.org/">Raspbian</a> based images.</p>
 138
 139       </div>
 140       <div class="tags">
 141
 142
 143         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox</a>, <a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network</a>.
 144
 145
 146       </div>
 147     </div>
 148     <div class="padding"></div>
 149
 150     <div class="entry">
 151       <div class="title">
 152         <a href="http://people.skolelinux.org/pere/blog/A_Raspberry_Pi_based_batman_adv_Mesh_network_node.html">A Raspberry Pi based batman-adv Mesh network node</a>
 153       </div>
 154       <div class="date">
 155         21st October 2013
 156       </div>
 157       <div class="body">
 158         <p>The last few days I have been experimenting with
 159 <a href="http://www.open-mesh.org/projects/batman-adv/wiki">the
 160 batman-adv mesh technology</a>.  I want to gain some experience to see
 161 if it will fit <a href="https://wiki.debian.org/FreedomBox">the
 162 Freedombox project</a>, and together with my neighbors try to build a
 163 mesh network around the park where I live.  Batman-adv is a layer 2
 164 mesh system ("ethernet" in other words), where the mesh network appear
 165 as if all the mesh clients are connected to the same switch.</p>
 166
 167 <p>My hardware of choice was the Linksys WRT54GL routers I had lying
 168 around, but I've been unable to get them working with batman-adv.  So
 169 instead, I started playing with a
 170 <a href="http://www.raspberrypi.org/">Raspberry Pi</a>, and tried to
 171 get it working as a mesh node.  My idea is to use it to create a mesh
 172 node which function as a switch port, where everything connected to
 173 the Raspberry Pi ethernet plug is connected (bridged) to the mesh
 174 network.  This allow me to hook a wifi base station like the Linksys
 175 WRT54GL to the mesh by plugging it into a Raspberry Pi, and allow
 176 non-mesh clients to hook up to the mesh.  This in turn is useful for
 177 Android phones using <a href="http://servalproject.org/">the Serval
 178 Project</a> voip client, allowing every one around the playground to
 179 phone and message each other for free.  The reason is that Android
 180 phones do not see ad-hoc wifi networks (they are filtered away from
 181 the GUI view), and can not join the mesh without being rooted.  But if
 182 they are connected using a normal wifi base station, they can talk to
 183 every client on the local network.</p>
 184
 185 <p>To get this working, I've created a debian package
 186 <a href="https://github.com/petterreinholdtsen/meshfx-node">meshfx-node</a>
 187 and a script
 188 <a href="https://github.com/petterreinholdtsen/meshfx-node/blob/master/build-rpi-mesh-node">build-rpi-mesh-node</a>
 189 to create the Raspberry Pi boot image.  I'm using Debian Jessie (and
 190 not Raspbian), to get more control over the packages available.
 191 Unfortunately a huge binary blob need to be inserted into the boot
 192 image to get it booting, but I'll ignore that for now.  Also, as
 193 Debian lack support for the CPU features available in the Raspberry
 194 Pi, the system do not use the hardware floating point unit.  I hope
 195 the routing performance isn't affected by the lack of hardware FPU
 196 support.</p>
 197
 198 <p>To create an image, run the following with a sudo enabled user
 199 after inserting the target SD card into the build machine:</p>
 200
 201 <p><pre>
 202 % wget -O build-rpi-mesh-node \
 203     https://raw.github.com/petterreinholdtsen/meshfx-node/master/build-rpi-mesh-node
 204 % sudo bash -x ./build-rpi-mesh-node > build.log 2>&1
 205 % dd if=/root/rpi/rpi_basic_jessie_$(date +%Y%m%d).img of=/dev/mmcblk0 bs=1M
 206 %
 207 </pre></p>
 208
 209 <p>Booting with the resulting SD card on a Raspberry PI with a USB
 210 wifi card inserted should give you a mesh node.  At least it does for
 211 me with a the wifi card I am using. The default mesh settings are the
 212 ones used by the Oslo mesh project at Hackeriet, as I mentioned in
 213 <a href="http://people.skolelinux.org/pere/blog/Oslo_community_mesh_network___with_NUUG_and_Hackeriet_at_Hausmania.html">an
 214 earlier blog post about this mesh testing</a>.</p>
 215
 216 <p>The mesh node was not horribly expensive either.  I bought
 217 everything over the counter in shops nearby.  If I had ordered online
 218 from the lowest bidder, the price should be significantly lower:</p>
 219
 220 <p><table>
 221
 222 <tr><th>Supplier</th><th>Model</th><th>NOK</th></tr>
 223 <tr><td>Teknikkmagasinet</td><td>Raspberry Pi model B</td><td>349.90</td></tr>
 224 <tr><td>Teknikkmagasinet</td><td>Raspberry Pi type B case</td><td>99.90</td></tr>
 225 <tr><td>Lefdal</td><td>Jensen Air:Link 25150</td><td>295.-</td></tr>
 226 <tr><td>Clas Ohlson</td><td>Kingston 16 GB SD card</td><td>199.-</td></tr>
 227 <tr><td>Total cost</td><td></td><td>943.80</td></tr>
 228
 229 </table></p>
 230
 231 <p>Now my mesh network at home consist of one laptop in the basement
 232 connected to my production network, one Raspberry Pi node on the 1th
 233 floor that can be seen by my neighbor across the park, and one
 234 play-node I use to develop the image building script.  And some times
 235 I hook up my work horse laptop to the mesh to test it.  I look forward
 236 to figuring out what kind of latency the batman-adv setup will give,
 237 and how much packet loss we will experience around the park. :)</p>
 238
 239       </div>
 240       <div class="tags">
 241
 242
 243         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox</a>, <a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>.
 244
 245
 246       </div>
 247     </div>
 248     <div class="padding"></div>
 249
 250     <div class="entry">
 251       <div class="title">
 252         <a href="http://people.skolelinux.org/pere/blog/Oslo_community_mesh_network___with_NUUG_and_Hackeriet_at_Hausmania.html">Oslo community mesh network - with NUUG and Hackeriet at Hausmania</a>
 253       </div>
 254       <div class="date">
 255         11th October 2013
 256       </div>
 257       <div class="body">
 258         <p>Wireless mesh networks are self organising and self healing
 259 networks that can be used to connect computers across small and large
 260 areas, depending on the radio technology used.  Normal wifi equipment
 261 can be used to create home made radio networks, and there are several
 262 successful examples like
 263 <a href="http://www.freifunk.net/">Freifunk</a> and
 264 <a href="http://www.awmn.net/">Athens Wireless Metropolitan Network</a>
 265 (see
 266 <a href="http://en.wikipedia.org/wiki/List_of_wireless_community_networks_by_region#Greece">wikipedia
 267 for a large list</a>) around the globe.  To give you an idea how it
 268 work, check out the nice overview of the Kiel Freifunk community which
 269 can be seen from their
 270 <a href="http://freifunk.in-kiel.de/ffmap/nodes.html">dynamically
 271 updated node graph and map</a>, where one can see how the mesh nodes
 272 automatically handle routing and recover from nodes disappearing.
 273 There is also a small community mesh network group in Oslo, Norway,
 274 and that is the main topic of this blog post.</p>
 275
 276 <p>I've wanted to check out mesh networks for a while now, and hoped
 277 to do it as part of my involvement with the <a
 278 href="http://www.nuug.no/">NUUG member organisation</a> community, and
 279 my recent involvement in
 280 <a href="https://wiki.debian.org/FreedomBox">the Freedombox project</a>
 281 finally lead me to give mesh networks some priority, as I suspect a
 282 Freedombox should use mesh networks to connect neighbours and family
 283 when possible, given that most communication between people are
 284 between those nearby (as shown for example by research on Facebook
 285 communication patterns).  It also allow people to communicate without
 286 any central hub to tap into for those that want to listen in on the
 287 private communication of citizens, which have become more and more
 288 important over the years.</p>
 289
 290 <p>So far I have only been able to find one group of people in Oslo
 291 working on community mesh networks, over at the hack space
 292 <a href="http://hackeriet.no/">Hackeriet</a> at Husmania.  They seem to
 293 have started with some Freifunk based effort using OLSR, called
 294 <a href="http://oslo.freifunk.net/index.php?title=Main_Page">the Oslo
 295 Freifunk project</a>, but that effort is now dead and the people
 296 behind it have moved on to a batman-adv based system called
 297 <a href="http://meshfx.org/trac">meshfx</a>.  Unfortunately the wiki
 298 site for the Oslo Freifunk project is no longer possible to update to
 299 reflect this fact, so the old project page can't be updated to point to
 300 the new project.  A while back, the people at Hackeriet invited people
 301 from the Freifunk community to Oslo to talk about mesh networks.  I
 302 came across this video where Hans Jørgen Lysglimt interview the
 303 speakers about this talk (from
 304 <a href="https://www.youtube.com/watch?v=N2Kd7CLkhSY">youtube</a>):</p>
 305
 306 <p><iframe width="420" height="315" src="https://www.youtube.com/embed/N2Kd7CLkhSY" frameborder="0" allowfullscreen></iframe></p>
 307
 308 <p>I mentioned OLSR and batman-adv, which are mesh routing protocols.
 309 There are heaps of different protocols, and I am still struggling to
 310 figure out which one would be "best" for some definitions of best, but
 311 given that the community mesh group in Oslo is so small, I believe it
 312 is best to hook up with the existing one instead of trying to create a
 313 completely different setup, and thus I have decided to focus on
 314 batman-adv for now.  It sure help me to  know that the very cool
 315 <a href="http://www.servalproject.org/">Serval project in Australia</a>
 316 is using batman-adv as their meshing technology when it create a self
 317 organizing and self healing telephony system for disaster areas and
 318 less industrialized communities.  Check out this cool video presenting
 319 that project (from
 320 <a href="https://www.youtube.com/watch?v=30qNfzJCQOA">youtube</a>):</p>
 321
 322 <p><iframe width="560" height="315" src="https://www.youtube.com/embed/30qNfzJCQOA" frameborder="0" allowfullscreen></iframe></p>
 323
 324 <p>According to the wikipedia page on
 325 <a href="http://en.wikipedia.org/wiki/Wireless_mesh_network">Wireless
 326 mesh network</a> there are around 70 competing schemes for routing
 327 packets across mesh networks, and OLSR, B.A.T.M.A.N. and
 328 B.A.T.M.A.N. advanced are protocols used by several free software
 329 based community mesh networks.</p>
 330
 331 <p>The batman-adv protocol is a bit special, as it provide layer 2
 332 (as in ethernet ) routing, allowing ipv4 and ipv6 to work on the same
 333 network.  One way to think about it is that it provide a mesh based
 334 vlan you can bridge to or handle like any other vlan connected to your
 335 computer.  The required drivers are already in the Linux kernel at
 336 least since Debian Wheezy, and it is fairly easy to set up.  A
 337 <a href="http://www.open-mesh.org/projects/batman-adv/wiki/Quick-start-guide">good
 338 introduction</a> is available from the Open Mesh project.  These are
 339 the key settings needed to join the Oslo meshfx network:</p>
 340
 341 <p><table>
 342 <tr><th>Setting</th><th>Value</th></tr>
 343 <tr><td>Protocol / kernel module</td><td>batman-adv</td></tr>
 344 <tr><td>ESSID</td><td>meshfx@hackeriet</td></tr>
 345 <td>Channel / Frequency</td><td>11 / 2462</td></tr>
 346 <td>Cell ID</td><td>02:BA:00:00:00:01</td>
 347 </table></p>
 348
 349 <p>The reason for setting ad-hoc wifi Cell ID is to work around bugs
 350 in firmware used in wifi card and wifi drivers.  (See a nice post from
 351 VillageTelco about
 352 "<a href="http://tiebing.blogspot.no/2009/12/ad-hoc-cell-splitting-re-post-original.html">Information
 353 about cell-id splitting, stuck beacons, and failed IBSS merges!</a>
 354 for details.)  When these settings are activated and you have some
 355 other mesh node nearby, your computer will be connected to the mesh
 356 network and can communicate with any mesh node that is connected to
 357 any of the nodes in your network of nodes. :)</p>
 358
 359 <p>My initial plan was to reuse my old Linksys WRT54GL as a mesh node,
 360 but that seem to be very hard, as I have not been able to locate a
 361 firmware supporting batman-adv.  If anyone know how to use that old
 362 wifi access point with batman-adv these days, please let me know.</p>
 363
 364 <p>If you find this project interesting and want to join, please join
 365 us on IRC, either channel
 366 <a href="irc://irc.freenode.net/#oslohackerspace">#oslohackerspace</a>
 367 or <a href="irc://irc.freenode.net/#nuug">#nuug</a> on
 368 irc.freenode.net.</p>
 369
 370 <p>While investigating mesh networks in Oslo, I came across an old
 371 research paper from the university of Stavanger and Telenor Research
 372 and Innovation called
 373 <a href="http://folk.uio.no/paalee/publications/netrel-egeland-iswcs-2008.pdf">The
 374 reliability of wireless backhaul mesh networks</a> and elsewhere
 375 learned that Telenor have been experimenting with mesh networks at
 376 Grünerløkka in Oslo.  So mesh networks are also interesting for
 377 commercial companies, even though Telenor discovered that it was hard
 378 to figure out a good business plan for mesh networking and as far as I
 379 know have closed down the experiment.  Perhaps Telenor or others would
 380 be interested in a cooperation?</p>
 381
 382 <p><strong>Update 2013-10-12</strong>: I was just
 383 <a href="http://lists.alioth.debian.org/pipermail/freedombox-discuss/2013-October/005900.html">told
 384 by the Serval project developers</a> that they no longer use
 385 batman-adv (but are compatible with it), but their own crypto based
 386 mesh system.</p>
 387
 388       </div>
 389       <div class="tags">
 390
 391
 392         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox</a>, <a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>.
 393
 394
 395       </div>
 396     </div>
 397     <div class="padding"></div>
 398
 399     <p style="text-align: right;"><a href="mesh network.rss"><img src="http://people.skolelinux.org/pere/blog/xml.gif" alt="RSS Feed" width="36" height="14" /></a></p>
 400     <div id="sidebar">
 401
 402
 403
 404 <h2>Archive</h2>
 405 <ul>
 406
 407 <li>2013
 408 <ul>
 409
 410 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
 411
 412 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
 413
 414 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
 415
 416 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
 417
 418 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
 419
 420 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
 421
 422 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
 423
 424 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
 425
 426 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
 427
 428 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
 429
 430 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/11/">November (1)</a></li>
 431
 432 </ul></li>
 433
 434 <li>2012
 435 <ul>
 436
 437 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
 438
 439 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
 440
 441 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
 442
 443 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
 444
 445 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
 446
 447 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
 448
 449 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
 450
 451 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
 452
 453 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
 454
 455 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
 456
 457 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
 458
 459 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
 460
 461 </ul></li>
 462
 463 <li>2011
 464 <ul>
 465
 466 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
 467
 468 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
 469
 470 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
 471
 472 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
 473
 474 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
 475
 476 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
 477
 478 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
 479
 480 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
 481
 482 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
 483
 484 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
 485
 486 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
 487
 488 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
 489
 490 </ul></li>
 491
 492 <li>2010
 493 <ul>
 494
 495 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
 496
 497 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
 498
 499 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
 500
 501 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
 502
 503 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
 504
 505 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
 506
 507 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
 508
 509 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
 510
 511 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
 512
 513 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
 514
 515 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
 516
 517 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
 518
 519 </ul></li>
 520
 521 <li>2009
 522 <ul>
 523
 524 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
 525
 526 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
 527
 528 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
 529
 530 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
 531
 532 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
 533
 534 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
 535
 536 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
 537
 538 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
 539
 540 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
 541
 542 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
 543
 544 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
 545
 546 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
 547
 548 </ul></li>
 549
 550 <li>2008
 551 <ul>
 552
 553 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
 554
 555 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
 556
 557 </ul></li>
 558
 559 </ul>
 560
 561
 562
 563 <h2>Tags</h2>
 564 <ul>
 565
 566  <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (13)</a></li>
 567
 568  <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
 569
 570  <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
 571
 572  <li><a href="http://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
 573
 574  <li><a href="http://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (7)</a></li>
 575
 576  <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (12)</a></li>
 577
 578  <li><a href="http://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
 579
 580  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (89)</a></li>
 581
 582  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (142)</a></li>
 583
 584  <li><a href="http://people.skolelinux.org/pere/blog/tags/digistan">digistan (10)</a></li>
 585
 586  <li><a href="http://people.skolelinux.org/pere/blog/tags/docbook">docbook (10)</a></li>
 587
 588  <li><a href="http://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
 589
 590  <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (224)</a></li>
 591
 592  <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (21)</a></li>
 593
 594  <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (12)</a></li>
 595
 596  <li><a href="http://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (12)</a></li>
 597
 598  <li><a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (5)</a></li>
 599
 600  <li><a href="http://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (11)</a></li>
 601
 602  <li><a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju (37)</a></li>
 603
 604  <li><a href="http://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (7)</a></li>
 605
 606  <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (18)</a></li>
 607
 608  <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (8)</a></li>
 609
 610  <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (6)</a></li>
 611
 612  <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
 613
 614  <li><a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (3)</a></li>
 615
 616  <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (25)</a></li>
 617
 618  <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (236)</a></li>
 619
 620  <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (156)</a></li>
 621
 622  <li><a href="http://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (8)</a></li>
 623
 624  <li><a href="http://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
 625
 626  <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (45)</a></li>
 627
 628  <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (67)</a></li>
 629
 630  <li><a href="http://people.skolelinux.org/pere/blog/tags/raid">raid (1)</a></li>
 631
 632  <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
 633
 634  <li><a href="http://people.skolelinux.org/pere/blog/tags/rfid">rfid (2)</a></li>
 635
 636  <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (8)</a></li>
 637
 638  <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
 639
 640  <li><a href="http://people.skolelinux.org/pere/blog/tags/ruter">ruter (4)</a></li>
 641
 642  <li><a href="http://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
 643
 644  <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (32)</a></li>
 645
 646  <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
 647
 648  <li><a href="http://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (4)</a></li>
 649
 650  <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (43)</a></li>
 651
 652  <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (3)</a></li>
 653
 654  <li><a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (9)</a></li>
 655
 656  <li><a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (20)</a></li>
 657
 658  <li><a href="http://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (1)</a></li>
 659
 660  <li><a href="http://people.skolelinux.org/pere/blog/tags/valg">valg (8)</a></li>
 661
 662  <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (39)</a></li>
 663
 664  <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
 665
 666  <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (28)</a></li>
 667
 668 </ul>
 669
 670
 671     </div>
 672     <p style="text-align: right">
 673  Created by <a href="http://steve.org.uk/Software/chronicle">Chronicle v4.6</a>
 674 </p>
 675
 676   </body>
 677 </html>