X-Git-Url: https://pere.pagekite.me/gitweb/homepage.git/blobdiff_plain/dc41b8f442e09aaf38c5e2bdbc61a66d6e74bbda..93f8b2c79949b69f126fab268095590bc294c673:/blog/archive/2013/10/10.rss diff --git a/blog/archive/2013/10/10.rss b/blog/archive/2013/10/10.rss index a4c123b23f..a736a11e53 100644 --- a/blog/archive/2013/10/10.rss +++ b/blog/archive/2013/10/10.rss @@ -6,6 +6,135 @@ http://people.skolelinux.org/pere/blog/ + + Oslo community mesh network - with NUUG and Hackeriet at Hausmania + http://people.skolelinux.org/pere/blog/Oslo_community_mesh_network___with_NUUG_and_Hackeriet_at_Hausmania.html + http://people.skolelinux.org/pere/blog/Oslo_community_mesh_network___with_NUUG_and_Hackeriet_at_Hausmania.html + Fri, 11 Oct 2013 14:10:00 +0200 + <p>Wireless mesh networks are self organising and self healing +networks that can be used to connect computers across small and large +areas, depending on the radio technology used. Normal wifi equipment +can be used to create home made radio networks, and there are several +successful examples like +<a href="http://www.freifunk.net/">Freifunk</a> and +<a href="http://www.awmn.net/">Athens Wireless Metropolitan Network</a> +(see +<a href="http://en.wikipedia.org/wiki/List_of_wireless_community_networks_by_region#Greece">wikipedia +for a large list</a>) around the globe. To give you an idea how it +work, check out the nice overview of the Kiel Freifunk community which +can be seen from their +<a href="http://freifunk.in-kiel.de/ffmap/nodes.html">dynamically +updated node graph and map</a>, where one can see how the mesh nodes +automatically handle routing and recover from nodes disappearing. +There is also a small community mesh network group in Oslo, Norway, +and that is the main topic of this blog post.</p> + +<p>I've wanted to check out mesh networks for a while now, and hoped +to do it as part of my involvement with the <a +href="http://www.nuug.no/">NUUG member organisation</a> community, and +my recent involvement in +<a href="https://wiki.debian.org/FreedomBox">the Freedombox project</a> +finally lead me to give mesh networks some priority, as I suspect a +Freedombox should use mesh networks to connect neighbours and family +when possible, given that most communication between people are +between those nearby (as shown for example by research on Facebook +communication patterns). It also allow people to communicate without +any central hub to tap into for those that want to listen in on the +private communication of citizens, which have become more and more +important over the years.</p> + +<p>So far I have only been able to find one group of people in Oslo +working on community mesh networks, over at the hack space +<a href="http://hackeriet.no/">Hackeriet</a> at Husmania. They seem to +have started with some Freifunk based effort using OLSR, called +<a href="http://oslo.freifunk.net/index.php?title=Main_Page">the Oslo +Freifunk project</a>, but that effort is now dead and the people +behind it have moved on to a batman-adv based system called +<a href="http://meshfx.org/trac">meshfx</a>. Unfortunately the wiki +site for the Oslo Freifunk project is no longer possible to update to +reflect this fact, so the old project page can't be updated to point to +the new project. A while back, the people at Hackeriet invited people +from the Freifunk community to Oslo to talk about mesh networks. I +came across this video where Hans Jørgen Lysglimt interview the +speakers about this talk:</p> + +<p><iframe width="420" height="315" src="https://www.youtube.com/embed/N2Kd7CLkhSY" frameborder="0" allowfullscreen></iframe></p> + +<p>I mentioned OLSR and batman-adv, which are mesh routing protocols. +There are heaps of different protocols, and I am still struggling to +figure out which one would be "best" for some definitions of best, but +given that the community mesh group in Oslo is so small, I believe it +is best to hook up with the existing one instead of trying to create a +completely different setup, and thus this have decided to focus on +batman-adv for now. It sure help me to know that the very cool +<a href="http://www.servalproject.org/">Serval project in Australia</a> +is using batman-adv as their meshing technology when it create a self +organizing and self healing telephony system for disaster areas and +less industrialized communities. Check out this cool video presenting +that project: + +<p><iframe width="560" height="315" src="https://www.youtube.com/embed/30qNfzJCQOA" frameborder="0" allowfullscreen></iframe></p> + +<p>According to the wikipedia page on +<a href="http://en.wikipedia.org/wiki/Wireless_mesh_network">Wireless +mesh network</a> there are around 70 competing schemes for routing +packets across mesh networks, and OLSR, B.A.T.M.A.N. and +B.A.T.M.A.N. advanced are protocols used by several free software +based community mesh networks.</p> + +</p>The batman-adv protocol is a bit special, as it provide layer 2 +(as in ethernet ) routing, allowing ipv4 and ipv6 to work on the same +network. One way to think about it is that it provide a mesh based +vlan you can bridge to or handle like any other vlan connected to your +computer. The required drivers are already in the Linux kernel at +least since Debian Wheezy, and it is fairly easy to set up. A +<a href="http://www.open-mesh.org/projects/batman-adv/wiki/Quick-start-guide">good +introduction</a> is available from the Open Mesh project. These are +the key settings needed to join the Oslo meshfx network:</p> + +<table> +<tr><th>Setting</th><th>Value</th></tr> +<tr><td>Protocol / kernel module</td><td>batman-adv</td></tr> +<tr><td>ESSID</td><td>meshfx@hackeriet</td></tr> +<td>Channel / Frequency</td><td>11 / 2462</td></tr> +<td>Cell ID</td><td>02:BA:00:00:00:01</td> +</table> + +<p>The reason for setting ad-hoc wifi Cell ID is to work around bugs +in firmware used in wifi card and wifi drivers. (See a nice post from +VillageTelco about +"<a href="http://tiebing.blogspot.no/2009/12/ad-hoc-cell-splitting-re-post-original.html">Information +about cell-id splitting, stuck beacons, and failed IBSS merges!</a> +for details.) When these settings are activated and you have some +other mesh node nearby, your computer will be connected to the mesh +network and can communicate with any mesh node that is connected to +any of the nodes in your network of nodes. :)</p> + +<p>My initial plan was to reuse my old Linksys WRT54GL as a mesh node, +but that seem to be very hard, as I have not been able to locate a +firmware supporting batman-adv. If anyone know how to use that old +wifi access point with batman-adv these days, please let me know.</p> + +<p>If you find this project interesting and want to join, please join +us on IRC, either channel +<a href="irc://irc.freenode.net/#oslohackerspace">#oslohackerspace</a> +or <a href="irc://irc.freenode.net/#nuug">#nuug</a> on +irc.freenode.net.</p> + +<p>While investigating mesh networks in Oslo, I came across an old +research paper from the university of Stavanger and Telenor Research +and Innovation called +<a href="http://folk.uio.no/paalee/publications/netrel-egeland-iswcs-2008.pdf">The +reliability of wireless backhaul mesh networks</a> and elsewhere +learned that Telenor have been experimenting with mesh networks at +Grünerløkka in Oslo. So mesh networks are also interesting for +commercial companies, even though Telenor discovered that it was hard +to figure out a good business plan for mesh networking and as far as I +know have closed down the experiment. Perhaps Telenor or others would +be interested in a cooperation?</p> + + + Skolelinux / Debian Edu 7.1 install and overview video from Marcelo Salvador http://people.skolelinux.org/pere/blog/Skolelinux___Debian_Edu_7_1_install_and_overview_video_from_Marcelo_Salvador.html