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  14  <h1>
  15      <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
  16
  17  </h1>
  18
  19 </div>
  20
  21
  22     <h3>Entries from October 2013.</h3>
  23
  24     <div class="entry">
  25       <div class="title">
  26         <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>
  27       </div>
  28       <div class="date">
  29         27th October 2013
  30       </div>
  31       <div class="body">
  32         <p>The
  33 <a href="http://packages.qa.debian.org/v/vmdebootstrap.html">vmdebootstrap</a>
  34 program is a a very nice system to create virtual machine images.  It
  35 create a image file, add a partition table, mount it and run
  36 debootstrap in the mounted directory to create a Debian system on a
  37 stick.  Yesterday, I decided to try to teach it how to make images for
  38 <a href="https://wiki.debian.org/RaspberryPi">Raspberry Pi</a>, as part
  39 of a plan to simplify the build system for the FreedomBox project.
  40 The FreedomBox project already uses vmdebootstrap for the virtualbox
  41 images, but its home made multistrap based system for Dreamplug
  42 images, and it is lacking support for Raspberry Pi.</p>
  43
  44 <p>Armed with the knowledge on how to build "foreign" (aka non-native
  45 architecture) chroots for Raspberry Pi, I dived into the vmdebootstrap
  46 code and adjusted it to be able to build armel images on my amd64
  47 Debian laptop.  I ended up giving vmdebootstrap five new options,
  48 allowing me to replicate the image creation process I use to make
  49 <a href=http://people.skolelinux.org/pere/blog/A_Raspberry_Pi_based_batman_adv_Mesh_network_node.html"">Debian
  50 Jessie based mesh node images for the Raspberry Pi</a>.  First, the
  51 <tt>--foreign /path/to/binfm_handler</tt> option tell vmdebootstrap to
  52 call debootstrap with --foreign and to copy the handler into the
  53 generated chroot before running the second stage.  This allow
  54 vmdebootstrap to create armel images on an amd64 host.  Next I added
  55 two new options <tt>--bootsize size</tt> and <tt>--boottype
  56 fstype</tt> to teach it to create a separate /boot/ partition with the
  57 given file system type, allowing me to create an image with a vfat
  58 partition for the /boot/ stuff.  I also added a <tt>--variant
  59 variant</tt> option to allow me to create smaller images without the
  60 Debian base system packages installed.  Finally, I added an option
  61 <tt>--no-extlinux</tt> to tell vmdebootstrap to not install extlinux
  62 as a boot loader.  It is not needed on the Raspberry Pi and probably
  63 most other non-x86 architectures.  The changes were accepted by the
  64 upstream author of vmdebootstrap yesterday and today, and is now
  65 available from
  66 <a href="http://git.liw.fi/cgi-bin/cgit/cgit.cgi/vmdebootstrap/">the
  67 upstream project page</a>.</p>
  68
  69 <p>To use it to build a Raspberry Pi image using Debian Jessie, first
  70 create a small script (the customize script) to add the non-free
  71 binary blob needed to boot the Raspberry Pi and the APT source
  72 list:</p>
  73
  74 <p><pre>
  75 #!/bin/sh
  76 set -e # Exit on first error
  77 rootdir="$1"
  78 cd "$rootdir"
  79 cat <<EOF > etc/apt/sources.list
  80 deb http://http.debian.net/debian/ jessie main contrib non-free
  81 EOF
  82 # Install non-free binary blob needed to boot Raspberry Pi.  This
  83 # install a kernel somewhere too.
  84 wget https://raw.github.com/Hexxeh/rpi-update/master/rpi-update \
  85     -O $rootdir/usr/bin/rpi-update
  86 chmod a+x $rootdir/usr/bin/rpi-update
  87 mkdir -p $rootdir/lib/modules
  88 touch $rootdir/boot/start.elf
  89 chroot $rootdir rpi-update
  90 </pre></p>
  91
  92 <p>Next, fetch the latest vmdebootstrap script and call it like this
  93 to build the image:</p>
  94
  95 <pre>
  96 sudo ./vmdebootstrap \
  97     --variant minbase \
  98     --arch armel \
  99     --distribution jessie \
 100     --mirror http://http.debian.net/debian \
 101     --image test.img \
 102     --size 600M \
 103     --bootsize 64M \
 104     --boottype vfat \
 105     --log-level debug \
 106     --verbose \
 107     --no-kernel \
 108     --no-extlinux \
 109     --root-password raspberry \
 110     --hostname raspberrypi \
 111     --foreign /usr/bin/qemu-arm-static \
 112     --customize `pwd`/customize \
 113     --package netbase \
 114     --package git-core \
 115     --package binutils \
 116     --package ca-certificates \
 117     --package wget \
 118     --package kmod
 119 </pre></p>
 120
 121 <p>The list of packages being installed are the ones needed by
 122 rpi-update to make the image bootable on the Raspberry Pi, with the
 123 exception of netbase, which is needed by debootstrap to find
 124 /etc/hosts with the minbase variant.  I really wish there was a way to
 125 set up an Raspberry Pi using only packages in the Debian archive, but
 126 that is not possible as far as I know, because it boots from the GPU
 127 using a non-free binary blob.</p>
 128
 129 <p>The build host need debootstrap, kpartx and qemu-user-static and
 130 probably a few others installed.  I have not checked the complete
 131 build dependency list.</p>
 132
 133 <p>The resulting image will not use the hardware floating point unit
 134 on the Raspberry PI, because the armel architecture in Debian is not
 135 optimized for that use.  So the images created will be a bit slower
 136 than <a href="http://www.raspbian.org/">Raspbian</a> based images.</p>
 137
 138       </div>
 139       <div class="tags">
 140
 141
 142         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>.
 143
 144
 145       </div>
 146     </div>
 147     <div class="padding"></div>
 148
 149     <div class="entry">
 150       <div class="title">
 151         <a href="http://people.skolelinux.org/pere/blog/Det_er_jo_makta_som_er_mest_s_rbar_ved_massiv_overv_kning_av_Internett.html">Det er jo makta som er mest sårbar ved massiv overvåkning av Internett</a>
 152       </div>
 153       <div class="date">
 154         26th October 2013
 155       </div>
 156       <div class="body">
 157         <p>De siste måneders eksponering av
 158 <a href="http://www.aftenposten.no/nyheter/uriks/Her-er-Edvard-Snowdens-mest-omtalte-avsloringer-7351734.html">den
 159 totale overvåkningen som foregår i den vestlige verden dokumenterer
 160 hvor sårbare vi er</a>.  Men det slår meg at de som er mest sårbare
 161 for dette, myndighetspersoner på alle nivåer, neppe har innsett at de
 162 selv er de mest interessante personene å lage profiler på, for å kunne
 163 påvirke dem.</p>
 164
 165 <p>For å ta et lite eksempel: Stortingets nettsted,
 166 <a href="http://www.stortinget.no/">www.stortinget.no</a> (og
 167 forsåvidt også
 168 <a href="http://data.stortinget.no/">data.stortinget.no</a>),
 169 inneholder informasjon om det som foregår på Stortinget, og jeg antar
 170 de største brukerne av informasjonen der er representanter og
 171 rådgivere på Stortinget.  Intet overraskende med det.  Det som derimot
 172 er mer skjult er at Stortingets nettsted bruker
 173 <a href="http://en.wikipedia.org/wiki/Google_Analytics">Google
 174 Analytics</a>, hvilket gjør at enhver som besøker nettsidene der også
 175 rapporterer om besøket via Internett-linjer som passerer Sverige,
 176 England og videre til USA.  Det betyr at informasjon om ethvert besøk
 177 på stortingets nettsider kan snappes opp av svensk, britisk og USAs
 178 etterretningsvesen.  De kan dermed holde et øye med hvilke
 179 Stortingssaker stortingsrepresentantene synes er interessante å sjekke
 180 ut, og hvilke sider rådgivere og andre på stortinget synes er
 181 interessant å besøke, når de gjør det og hvilke andre representanter
 182 som sjekker de samme sidene omtrent samtidig.  Stortingets bruk av
 183 Google Analytics gjør det dermed enkelt for utenlands etteretning å
 184 spore representantenes aktivitet og interesse.  Hvis noen av
 185 representantene bruker Google Mail eller noen andre tjenestene som
 186 krever innlogging, så vil det være enda enklere å finne ut nøyaktig
 187 hvilke personer som bruker hvilke nettlesere og dermed knytte
 188 informasjonen opp til enkeltpersoner på Stortinget.</p>
 189
 190 <p>Og jo flere nettsteder som bruker Google Analytics, jo bedre
 191 oversikt over stortingsrepresentantenes lesevaner og interesse blir
 192 tilgjengelig for svensk, britisk og USAs etterretning.  Hva de kan
 193 bruke den informasjonen til overlater jeg til leseren å undres
 194 over.</p>
 195
 196       </div>
 197       <div class="tags">
 198
 199
 200         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>, <a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>, <a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet</a>, <a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget</a>, <a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>.
 201
 202
 203       </div>
 204     </div>
 205     <div class="padding"></div>
 206
 207     <div class="entry">
 208       <div class="title">
 209         <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>
 210       </div>
 211       <div class="date">
 212         21st October 2013
 213       </div>
 214       <div class="body">
 215         <p>The last few days I have been experimenting with
 216 <a href="http://www.open-mesh.org/projects/batman-adv/wiki">the
 217 batman-adv mesh technology</a>.  I want to gain some experience to see
 218 if it will fit <a href="https://wiki.debian.org/FreedomBox">the
 219 Freedombox project</a>, and together with my neighbors try to build a
 220 mesh network around the park where I live.  Batman-adv is a layer 2
 221 mesh system ("ethernet" in other words), where the mesh network appear
 222 as if all the mesh clients are connected to the same switch.</p>
 223
 224 <p>My hardware of choice was the Linksys WRT54GL routers I had lying
 225 around, but I've been unable to get them working with batman-adv.  So
 226 instead, I started playing with a
 227 <a href="http://www.raspberrypi.org/">Raspberry Pi</a>, and tried to
 228 get it working as a mesh node.  My idea is to use it to create a mesh
 229 node which function as a switch port, where everything connected to
 230 the Raspberry Pi ethernet plug is connected (bridged) to the mesh
 231 network.  This allow me to hook a wifi base station like the Linksys
 232 WRT54GL to the mesh by plugging it into a Raspberry Pi, and allow
 233 non-mesh clients to hook up to the mesh.  This in turn is useful for
 234 Android phones using <a href="http://servalproject.org/">the Serval
 235 Project</a> voip client, allowing every one around the playground to
 236 phone and message each other for free.  The reason is that Android
 237 phones do not see ad-hoc wifi networks (they are filtered away from
 238 the GUI view), and can not join the mesh without being rooted.  But if
 239 they are connected using a normal wifi base station, they can talk to
 240 every client on the local network.</p>
 241
 242 <p>To get this working, I've created a debian package
 243 <a href="https://github.com/petterreinholdtsen/meshfx-node">meshfx-node</a>
 244 and a script
 245 <a href="https://github.com/petterreinholdtsen/meshfx-node/blob/master/build-rpi-mesh-node">build-rpi-mesh-node</a>
 246 to create the Raspberry Pi boot image.  I'm using Debian Jessie (and
 247 not Raspbian), to get more control over the packages available.
 248 Unfortunately a huge binary blob need to be inserted into the boot
 249 image to get it booting, but I'll ignore that for now.  Also, as
 250 Debian lack support for the CPU features available in the Raspberry
 251 Pi, the system do not use the hardware floating point unit.  I hope
 252 the routing performance isn't affected by the lack of hardware FPU
 253 support.</p>
 254
 255 <p>To create an image, run the following with a sudo enabled user
 256 after inserting the target SD card into the build machine:</p>
 257
 258 <p><pre>
 259 % wget -O build-rpi-mesh-node \
 260     https://raw.github.com/petterreinholdtsen/meshfx-node/master/build-rpi-mesh-node
 261 % sudo bash -x ./build-rpi-mesh-node > build.log 2>&1
 262 % dd if=/root/rpi/rpi_basic_jessie_$(date +%Y%m%d).img of=/dev/mmcblk0 bs=1M
 263 %
 264 </pre></p>
 265
 266 <p>Booting with the resulting SD card on a Raspberry PI with a USB
 267 wifi card inserted should give you a mesh node.  At least it does for
 268 me with a the wifi card I am using. The default mesh settings are the
 269 ones used by the Oslo mesh project at Hackeriet, as I mentioned in
 270 <a href="http://people.skolelinux.org/pere/blog/Oslo_community_mesh_network___with_NUUG_and_Hackeriet_at_Hausmania.html">an
 271 earlier blog post about this mesh testing</a>.</p>
 272
 273 <p>The mesh node was not horribly expensive either.  I bought
 274 everything over the counter in shops nearby.  If I had ordered online
 275 from the lowest bidder, the price should be significantly lower:</p>
 276
 277 <p><table>
 278
 279 <tr><th>Supplier</th><th>Model</th><th>NOK</th></tr>
 280 <tr><td>Teknikkmagasinet</td><td>Raspberry Pi model B</td><td>349.90</td></tr>
 281 <tr><td>Teknikkmagasinet</td><td>Raspberry Pi type B case</td><td>99.90</td></tr>
 282 <tr><td>Lefdal</td><td>Jensen Air:Link 25150</td><td>295.-</td></tr>
 283 <tr><td>Clas Ohlson</td><td>Kingston 16 GB SD card</td><td>199.-</td></tr>
 284 <tr><td>Total cost</td><td></td><td>943.80</td></tr>
 285
 286 </table></p>
 287
 288 <p>Now my mesh network at home consist of one laptop in the basement
 289 connected to my production network, one Raspberry Pi node on the 1th
 290 floor that can be seen by my neighbor across the park, and one
 291 play-node I use to develop the image building script.  And some times
 292 I hook up my work horse laptop to the mesh to test it.  I look forward
 293 to figuring out what kind of latency the batman-adv setup will give,
 294 and how much packet loss we will experience around the park. :)</p>
 295
 296       </div>
 297       <div class="tags">
 298
 299
 300         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>.
 301
 302
 303       </div>
 304     </div>
 305     <div class="padding"></div>
 306
 307     <div class="entry">
 308       <div class="title">
 309         <a href="http://people.skolelinux.org/pere/blog/Perl_library_to_control_the_Spykee_robot_moved_to_github.html">Perl library to control the Spykee robot moved to github</a>
 310       </div>
 311       <div class="date">
 312         19th October 2013
 313       </div>
 314       <div class="body">
 315         <p>Back in 2010, I created a Perl library to talk to
 316 <a href="http://en.wikipedia.org/wiki/Spykee">the Spykee robot</a>
 317 (with two belts, wifi, USB and Linux) and made it available from my
 318 web page.  Today I concluded that it should move to a site that is
 319 easier to use to cooperate with others, and moved it to github.  If
 320 you got a Spykee robot, you might want to check out
 321 <a href="https://github.com/petterreinholdtsen/libspykee-perl">the
 322 libspykee-perl github repository</a>.</p>
 323
 324       </div>
 325       <div class="tags">
 326
 327
 328         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>, <a href="http://people.skolelinux.org/pere/blog/tags/robot">robot</a>.
 329
 330
 331       </div>
 332     </div>
 333     <div class="padding"></div>
 334
 335     <div class="entry">
 336       <div class="title">
 337         <a href="http://people.skolelinux.org/pere/blog/Good_causes__Debian_Outreach_Program_for_Women__EFF_documenting_the_spying_and_Open_access_in_Norway.html">Good causes: Debian Outreach Program for Women, EFF documenting the spying and Open access in Norway</a>
 338       </div>
 339       <div class="date">
 340         15th October 2013
 341       </div>
 342       <div class="body">
 343         <p>The last few days I came across a few good causes that should get
 344 wider attention.  I recommend signing and donating to each one of
 345 these. :)</p>
 346
 347 <p>Via <a href="http://www.debian.org/News/weekly/2013/18/">Debian
 348 Project News for 2013-10-14</a> I came across the Outreach Program for
 349 Women program which is a Google Summer of Code like initiative to get
 350 more women involved in free software.  One debian sponsor has offered
 351 to match <a href="http://debian.ch/opw2013">any donation done to Debian
 352 earmarked</a> for this initiative.  I donated a few minutes ago, and
 353 hope you will to. :)</p>
 354
 355 <p>And the Electronic Frontier Foundation just announced plans to
 356 create <a href="https://supporters.eff.org/donate/nsa-videos">video
 357 documentaries about the excessive spying</a> on every Internet user that
 358 take place these days, and their need to fund the work.  I've already
 359 donated.  Are you next?</p>
 360
 361 <p>For my Norwegian audience, the organisation Studentenes og
 362 Akademikernes Internasjonale Hjelpefond is collecting signatures for a
 363 statement under the heading
 364 <a href="http://saih.no/Bloggers_United/">Bloggers United for Open
 365 Access</a> for those of us asking for more focus on open access in the
 366 Norwegian government.  So far 499 signatures.  I hope you will sign it
 367 too.</p>
 368
 369       </div>
 370       <div class="tags">
 371
 372
 373         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/opphavsrett">opphavsrett</a>, <a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>.
 374
 375
 376       </div>
 377     </div>
 378     <div class="padding"></div>
 379
 380     <div class="entry">
 381       <div class="title">
 382         <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>
 383       </div>
 384       <div class="date">
 385         11th October 2013
 386       </div>
 387       <div class="body">
 388         <p>Wireless mesh networks are self organising and self healing
 389 networks that can be used to connect computers across small and large
 390 areas, depending on the radio technology used.  Normal wifi equipment
 391 can be used to create home made radio networks, and there are several
 392 successful examples like
 393 <a href="http://www.freifunk.net/">Freifunk</a> and
 394 <a href="http://www.awmn.net/">Athens Wireless Metropolitan Network</a>
 395 (see
 396 <a href="http://en.wikipedia.org/wiki/List_of_wireless_community_networks_by_region#Greece">wikipedia
 397 for a large list</a>) around the globe.  To give you an idea how it
 398 work, check out the nice overview of the Kiel Freifunk community which
 399 can be seen from their
 400 <a href="http://freifunk.in-kiel.de/ffmap/nodes.html">dynamically
 401 updated node graph and map</a>, where one can see how the mesh nodes
 402 automatically handle routing and recover from nodes disappearing.
 403 There is also a small community mesh network group in Oslo, Norway,
 404 and that is the main topic of this blog post.</p>
 405
 406 <p>I've wanted to check out mesh networks for a while now, and hoped
 407 to do it as part of my involvement with the <a
 408 href="http://www.nuug.no/">NUUG member organisation</a> community, and
 409 my recent involvement in
 410 <a href="https://wiki.debian.org/FreedomBox">the Freedombox project</a>
 411 finally lead me to give mesh networks some priority, as I suspect a
 412 Freedombox should use mesh networks to connect neighbours and family
 413 when possible, given that most communication between people are
 414 between those nearby (as shown for example by research on Facebook
 415 communication patterns).  It also allow people to communicate without
 416 any central hub to tap into for those that want to listen in on the
 417 private communication of citizens, which have become more and more
 418 important over the years.</p>
 419
 420 <p>So far I have only been able to find one group of people in Oslo
 421 working on community mesh networks, over at the hack space
 422 <a href="http://hackeriet.no/">Hackeriet</a> at Husmania.  They seem to
 423 have started with some Freifunk based effort using OLSR, called
 424 <a href="http://oslo.freifunk.net/index.php?title=Main_Page">the Oslo
 425 Freifunk project</a>, but that effort is now dead and the people
 426 behind it have moved on to a batman-adv based system called
 427 <a href="http://meshfx.org/trac">meshfx</a>.  Unfortunately the wiki
 428 site for the Oslo Freifunk project is no longer possible to update to
 429 reflect this fact, so the old project page can't be updated to point to
 430 the new project.  A while back, the people at Hackeriet invited people
 431 from the Freifunk community to Oslo to talk about mesh networks.  I
 432 came across this video where Hans Jørgen Lysglimt interview the
 433 speakers about this talk (from
 434 <a href="https://www.youtube.com/watch?v=N2Kd7CLkhSY">youtube</a>):</p>
 435
 436 <p><iframe width="420" height="315" src="https://www.youtube.com/embed/N2Kd7CLkhSY" frameborder="0" allowfullscreen></iframe></p>
 437
 438 <p>I mentioned OLSR and batman-adv, which are mesh routing protocols.
 439 There are heaps of different protocols, and I am still struggling to
 440 figure out which one would be "best" for some definitions of best, but
 441 given that the community mesh group in Oslo is so small, I believe it
 442 is best to hook up with the existing one instead of trying to create a
 443 completely different setup, and thus I have decided to focus on
 444 batman-adv for now.  It sure help me to  know that the very cool
 445 <a href="http://www.servalproject.org/">Serval project in Australia</a>
 446 is using batman-adv as their meshing technology when it create a self
 447 organizing and self healing telephony system for disaster areas and
 448 less industrialized communities.  Check out this cool video presenting
 449 that project (from
 450 <a href="https://www.youtube.com/watch?v=30qNfzJCQOA">youtube</a>):</p>
 451
 452 <p><iframe width="560" height="315" src="https://www.youtube.com/embed/30qNfzJCQOA" frameborder="0" allowfullscreen></iframe></p>
 453
 454 <p>According to the wikipedia page on
 455 <a href="http://en.wikipedia.org/wiki/Wireless_mesh_network">Wireless
 456 mesh network</a> there are around 70 competing schemes for routing
 457 packets across mesh networks, and OLSR, B.A.T.M.A.N. and
 458 B.A.T.M.A.N. advanced are protocols used by several free software
 459 based community mesh networks.</p>
 460
 461 <p>The batman-adv protocol is a bit special, as it provide layer 2
 462 (as in ethernet ) routing, allowing ipv4 and ipv6 to work on the same
 463 network.  One way to think about it is that it provide a mesh based
 464 vlan you can bridge to or handle like any other vlan connected to your
 465 computer.  The required drivers are already in the Linux kernel at
 466 least since Debian Wheezy, and it is fairly easy to set up.  A
 467 <a href="http://www.open-mesh.org/projects/batman-adv/wiki/Quick-start-guide">good
 468 introduction</a> is available from the Open Mesh project.  These are
 469 the key settings needed to join the Oslo meshfx network:</p>
 470
 471 <p><table>
 472 <tr><th>Setting</th><th>Value</th></tr>
 473 <tr><td>Protocol / kernel module</td><td>batman-adv</td></tr>
 474 <tr><td>ESSID</td><td>meshfx@hackeriet</td></tr>
 475 <td>Channel / Frequency</td><td>11 / 2462</td></tr>
 476 <td>Cell ID</td><td>02:BA:00:00:00:01</td>
 477 </table></p>
 478
 479 <p>The reason for setting ad-hoc wifi Cell ID is to work around bugs
 480 in firmware used in wifi card and wifi drivers.  (See a nice post from
 481 VillageTelco about
 482 "<a href="http://tiebing.blogspot.no/2009/12/ad-hoc-cell-splitting-re-post-original.html">Information
 483 about cell-id splitting, stuck beacons, and failed IBSS merges!</a>
 484 for details.)  When these settings are activated and you have some
 485 other mesh node nearby, your computer will be connected to the mesh
 486 network and can communicate with any mesh node that is connected to
 487 any of the nodes in your network of nodes. :)</p>
 488
 489 <p>My initial plan was to reuse my old Linksys WRT54GL as a mesh node,
 490 but that seem to be very hard, as I have not been able to locate a
 491 firmware supporting batman-adv.  If anyone know how to use that old
 492 wifi access point with batman-adv these days, please let me know.</p>
 493
 494 <p>If you find this project interesting and want to join, please join
 495 us on IRC, either channel
 496 <a href="irc://irc.freenode.net/#oslohackerspace">#oslohackerspace</a>
 497 or <a href="irc://irc.freenode.net/#nuug">#nuug</a> on
 498 irc.freenode.net.</p>
 499
 500 <p>While investigating mesh networks in Oslo, I came across an old
 501 research paper from the university of Stavanger and Telenor Research
 502 and Innovation called
 503 <a href="http://folk.uio.no/paalee/publications/netrel-egeland-iswcs-2008.pdf">The
 504 reliability of wireless backhaul mesh networks</a> and elsewhere
 505 learned that Telenor have been experimenting with mesh networks at
 506 Grünerløkka in Oslo.  So mesh networks are also interesting for
 507 commercial companies, even though Telenor discovered that it was hard
 508 to figure out a good business plan for mesh networking and as far as I
 509 know have closed down the experiment.  Perhaps Telenor or others would
 510 be interested in a cooperation?</p>
 511
 512 <p><strong>Update 2013-10-12</strong>: I was just
 513 <a href="http://lists.alioth.debian.org/pipermail/freedombox-discuss/2013-October/005900.html">told
 514 by the Serval project developers</a> that they no longer use
 515 batman-adv (but are compatible with it), but their own crypto based
 516 mesh system.</p>
 517
 518       </div>
 519       <div class="tags">
 520
 521
 522         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>.
 523
 524
 525       </div>
 526     </div>
 527     <div class="padding"></div>
 528
 529     <div class="entry">
 530       <div class="title">
 531         <a href="http://people.skolelinux.org/pere/blog/Skolelinux___Debian_Edu_7_1_install_and_overview_video_from_Marcelo_Salvador.html">Skolelinux / Debian Edu 7.1 install and overview video from Marcelo Salvador</a>
 532       </div>
 533       <div class="date">
 534          8th October 2013
 535       </div>
 536       <div class="body">
 537         <p>The other day I was pleased and surprised to discover that Marcelo
 538 Salvador had published a
 539 <a href="https://www.youtube.com/watch?v=w-GgpdqgLFc">video on
 540 Youtube</a> showing how to install the standalone Debian Edu /
 541 Skolelinux profile.  This is the profile intended for use at home or
 542 on laptops that should not be integrated into the provided network
 543 services (no central home directory, no Kerberos / LDAP directory etc,
 544 in other word a single user machine).  The result is 11 minutes long,
 545 and show some user applications (seem to be rather randomly picked).
 546 Missed a few of my favorites like celestia, planets and chromium
 547 showing the <a href="http://www.zygotebody.com/">Zygote Body 3D model
 548 of the human body</a>, but I guess he did not know about those or find
 549 other programs more interesting. :) And the video do not show the
 550 advantages I believe is one of the most valuable featuers in Debian
 551 Edu, its central school server making it possible to run hundreds of
 552 computers without hard drives by installing one central
 553 <a href="http://www.ltsp.org/">LTSP server</a>.</p>
 554
 555 <p>Anyway, check out the video, embedded below and linked to above:</p>
 556
 557 <iframe width="420" height="315" src="http://www.youtube.com/embed/w-GgpdqgLFc" frameborder="0" allowfullscreen></iframe>
 558
 559 <p>Are there other nice videos demonstrating Skolelinux?  Please let
 560 me know. :)</p>
 561
 562       </div>
 563       <div class="tags">
 564
 565
 566         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/video">video</a>.
 567
 568
 569       </div>
 570     </div>
 571     <div class="padding"></div>
 572
 573     <p style="text-align: right;"><a href="10.rss"><img src="http://people.skolelinux.org/pere/blog/xml.gif" alt="RSS Feed" width="36" height="14" /></a></p>
 574     <div id="sidebar">
 575
 576
 577
 578 <h2>Archive</h2>
 579 <ul>
 580
 581 <li>2013
 582 <ul>
 583
 584 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
 585
 586 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
 587
 588 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
 589
 590 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
 591
 592 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
 593
 594 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
 595
 596 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
 597
 598 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
 599
 600 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
 601
 602 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
 603
 604 </ul></li>
 605
 606 <li>2012
 607 <ul>
 608
 609 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
 610
 611 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
 612
 613 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
 614
 615 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
 616
 617 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
 618
 619 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
 620
 621 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
 622
 623 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
 624
 625 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
 626
 627 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
 628
 629 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
 630
 631 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
 632
 633 </ul></li>
 634
 635 <li>2011
 636 <ul>
 637
 638 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
 639
 640 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
 641
 642 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
 643
 644 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
 645
 646 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
 647
 648 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
 649
 650 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
 651
 652 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
 653
 654 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
 655
 656 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
 657
 658 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
 659
 660 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
 661
 662 </ul></li>
 663
 664 <li>2010
 665 <ul>
 666
 667 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
 668
 669 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
 670
 671 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
 672
 673 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
 674
 675 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
 676
 677 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
 678
 679 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
 680
 681 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
 682
 683 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
 684
 685 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
 686
 687 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
 688
 689 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
 690
 691 </ul></li>
 692
 693 <li>2009
 694 <ul>
 695
 696 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
 697
 698 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
 699
 700 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
 701
 702 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
 703
 704 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
 705
 706 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
 707
 708 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
 709
 710 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
 711
 712 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
 713
 714 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
 715
 716 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
 717
 718 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
 719
 720 </ul></li>
 721
 722 <li>2008
 723 <ul>
 724
 725 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
 726
 727 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
 728
 729 </ul></li>
 730
 731 </ul>
 732
 733
 734
 735 <h2>Tags</h2>
 736 <ul>
 737
 738  <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (13)</a></li>
 739
 740  <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
 741
 742  <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
 743
 744  <li><a href="http://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
 745
 746  <li><a href="http://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (7)</a></li>
 747
 748  <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (12)</a></li>
 749
 750  <li><a href="http://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
 751
 752  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (88)</a></li>
 753
 754  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (142)</a></li>
 755
 756  <li><a href="http://people.skolelinux.org/pere/blog/tags/digistan">digistan (10)</a></li>
 757
 758  <li><a href="http://people.skolelinux.org/pere/blog/tags/docbook">docbook (10)</a></li>
 759
 760  <li><a href="http://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
 761
 762  <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (223)</a></li>
 763
 764  <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (21)</a></li>
 765
 766  <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (12)</a></li>
 767
 768  <li><a href="http://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (12)</a></li>
 769
 770  <li><a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (5)</a></li>
 771
 772  <li><a href="http://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (11)</a></li>
 773
 774  <li><a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju (37)</a></li>
 775
 776  <li><a href="http://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (7)</a></li>
 777
 778  <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (18)</a></li>
 779
 780  <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (8)</a></li>
 781
 782  <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (6)</a></li>
 783
 784  <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
 785
 786  <li><a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (3)</a></li>
 787
 788  <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (25)</a></li>
 789
 790  <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (236)</a></li>
 791
 792  <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (156)</a></li>
 793
 794  <li><a href="http://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (8)</a></li>
 795
 796  <li><a href="http://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
 797
 798  <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (45)</a></li>
 799
 800  <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (67)</a></li>
 801
 802  <li><a href="http://people.skolelinux.org/pere/blog/tags/raid">raid (1)</a></li>
 803
 804  <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
 805
 806  <li><a href="http://people.skolelinux.org/pere/blog/tags/rfid">rfid (2)</a></li>
 807
 808  <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (8)</a></li>
 809
 810  <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
 811
 812  <li><a href="http://people.skolelinux.org/pere/blog/tags/ruter">ruter (4)</a></li>
 813
 814  <li><a href="http://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
 815
 816  <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (32)</a></li>
 817
 818  <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
 819
 820  <li><a href="http://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (4)</a></li>
 821
 822  <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (43)</a></li>
 823
 824  <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (3)</a></li>
 825
 826  <li><a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (9)</a></li>
 827
 828  <li><a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (20)</a></li>
 829
 830  <li><a href="http://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (1)</a></li>
 831
 832  <li><a href="http://people.skolelinux.org/pere/blog/tags/valg">valg (8)</a></li>
 833
 834  <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (39)</a></li>
 835
 836  <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
 837
 838  <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (28)</a></li>
 839
 840 </ul>
 841
 842
 843     </div>
 844     <p style="text-align: right">
 845  Created by <a href="http://steve.org.uk/Software/chronicle">Chronicle v4.6</a>
 846 </p>
 847
 848   </body>
 849 </html>