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1 <?xml version="1.0" encoding="ISO-8859-1"?>
2 <rss version='2.0' xmlns:lj='http://www.livejournal.org/rss/lj/1.0/'>
3 <channel>
4 <title>Petter Reinholdtsen - Entries from October 2013</title>
5 <description>Entries from October 2013</description>
6 <link>http://people.skolelinux.org/pere/blog/</link>
7
8
9 <item>
10 <title>Perl library to control the Spykee robot moved to github</title>
11 <link>http://people.skolelinux.org/pere/blog/Perl_library_to_control_the_Spykee_robot_moved_to_github.html</link>
12 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Perl_library_to_control_the_Spykee_robot_moved_to_github.html</guid>
13 <pubDate>Sat, 19 Oct 2013 10:20:00 +0200</pubDate>
14 <description>&lt;p&gt;Back in 2010, I created a Perl library to talk to
15 &lt;a href=&quot;http://en.wikipedia.org/wiki/Spykee&quot;&gt;the Spykee robot&lt;/a&gt;
16 (with two belts, wifi, USB and Linux) and made it available from my
17 web page. Today I concluded that it should move to a site that is
18 easier to use to cooperate with others, and moved it to github. If
19 you got a Spykee robot, you might want to check out
20 &lt;a href=&quot;https://github.com/petterreinholdtsen/libspykee-perl&quot;&gt;the
21 libspykee-perl github repository&lt;/a&gt;.&lt;/p&gt;
22 </description>
23 </item>
24
25 <item>
26 <title>Good causes: Debian Outreach Program for Women, EFF documenting the spying and Open access in Norway</title>
27 <link>http://people.skolelinux.org/pere/blog/Good_causes__Debian_Outreach_Program_for_Women__EFF_documenting_the_spying_and_Open_access_in_Norway.html</link>
28 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Good_causes__Debian_Outreach_Program_for_Women__EFF_documenting_the_spying_and_Open_access_in_Norway.html</guid>
29 <pubDate>Tue, 15 Oct 2013 21:30:00 +0200</pubDate>
30 <description>&lt;p&gt;The last few days I came across a few good causes that should get
31 wider attention. I recommend signing and donating to each one of
32 these. :)&lt;/p&gt;
33
34 &lt;p&gt;Via &lt;a href=&quot;http://www.debian.org/News/weekly/2013/18/&quot;&gt;Debian
35 Project News for 2013-10-14&lt;/a&gt; I came across the Outreach Program for
36 Women program which is a Google Summer of Code like initiative to get
37 more women involved in free software. One debian sponsor has offered
38 to match &lt;a href=&quot;http://debian.ch/opw2013&quot;&gt;any donation done to Debian
39 earmarked&lt;/a&gt; for this initiative. I donated a few minutes ago, and
40 hope you will to. :)&lt;/p&gt;
41
42 &lt;p&gt;And the Electronic Frontier Foundation just announced plans to
43 create &lt;a href=&quot;https://supporters.eff.org/donate/nsa-videos&quot;&gt;video
44 documentaries about the excessive spying&lt;/a&gt; on every Internet user that
45 take place these days, and their need to fund the work. I&#39;ve already
46 donated. Are you next?&lt;/p&gt;
47
48 &lt;p&gt;For my Norwegian audience, the organisation Studentenes og
49 Akademikernes Internasjonale Hjelpefond is collecting signatures for a
50 statement under the heading
51 &lt;a href=&quot;http://saih.no/Bloggers_United/&quot;&gt;Bloggers United for Open
52 Access&lt;/a&gt; for those of us asking for more focus on open access in the
53 Norwegian government. So far 499 signatures. I hope you will sign it
54 too.&lt;/p&gt;
55 </description>
56 </item>
57
58 <item>
59 <title>Oslo community mesh network - with NUUG and Hackeriet at Hausmania</title>
60 <link>http://people.skolelinux.org/pere/blog/Oslo_community_mesh_network___with_NUUG_and_Hackeriet_at_Hausmania.html</link>
61 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Oslo_community_mesh_network___with_NUUG_and_Hackeriet_at_Hausmania.html</guid>
62 <pubDate>Fri, 11 Oct 2013 14:10:00 +0200</pubDate>
63 <description>&lt;p&gt;Wireless mesh networks are self organising and self healing
64 networks that can be used to connect computers across small and large
65 areas, depending on the radio technology used. Normal wifi equipment
66 can be used to create home made radio networks, and there are several
67 successful examples like
68 &lt;a href=&quot;http://www.freifunk.net/&quot;&gt;Freifunk&lt;/a&gt; and
69 &lt;a href=&quot;http://www.awmn.net/&quot;&gt;Athens Wireless Metropolitan Network&lt;/a&gt;
70 (see
71 &lt;a href=&quot;http://en.wikipedia.org/wiki/List_of_wireless_community_networks_by_region#Greece&quot;&gt;wikipedia
72 for a large list&lt;/a&gt;) around the globe. To give you an idea how it
73 work, check out the nice overview of the Kiel Freifunk community which
74 can be seen from their
75 &lt;a href=&quot;http://freifunk.in-kiel.de/ffmap/nodes.html&quot;&gt;dynamically
76 updated node graph and map&lt;/a&gt;, where one can see how the mesh nodes
77 automatically handle routing and recover from nodes disappearing.
78 There is also a small community mesh network group in Oslo, Norway,
79 and that is the main topic of this blog post.&lt;/p&gt;
80
81 &lt;p&gt;I&#39;ve wanted to check out mesh networks for a while now, and hoped
82 to do it as part of my involvement with the &lt;a
83 href=&quot;http://www.nuug.no/&quot;&gt;NUUG member organisation&lt;/a&gt; community, and
84 my recent involvement in
85 &lt;a href=&quot;https://wiki.debian.org/FreedomBox&quot;&gt;the Freedombox project&lt;/a&gt;
86 finally lead me to give mesh networks some priority, as I suspect a
87 Freedombox should use mesh networks to connect neighbours and family
88 when possible, given that most communication between people are
89 between those nearby (as shown for example by research on Facebook
90 communication patterns). It also allow people to communicate without
91 any central hub to tap into for those that want to listen in on the
92 private communication of citizens, which have become more and more
93 important over the years.&lt;/p&gt;
94
95 &lt;p&gt;So far I have only been able to find one group of people in Oslo
96 working on community mesh networks, over at the hack space
97 &lt;a href=&quot;http://hackeriet.no/&quot;&gt;Hackeriet&lt;/a&gt; at Husmania. They seem to
98 have started with some Freifunk based effort using OLSR, called
99 &lt;a href=&quot;http://oslo.freifunk.net/index.php?title=Main_Page&quot;&gt;the Oslo
100 Freifunk project&lt;/a&gt;, but that effort is now dead and the people
101 behind it have moved on to a batman-adv based system called
102 &lt;a href=&quot;http://meshfx.org/trac&quot;&gt;meshfx&lt;/a&gt;. Unfortunately the wiki
103 site for the Oslo Freifunk project is no longer possible to update to
104 reflect this fact, so the old project page can&#39;t be updated to point to
105 the new project. A while back, the people at Hackeriet invited people
106 from the Freifunk community to Oslo to talk about mesh networks. I
107 came across this video where Hans Jørgen Lysglimt interview the
108 speakers about this talk (from
109 &lt;a href=&quot;https://www.youtube.com/watch?v=N2Kd7CLkhSY&quot;&gt;youtube&lt;/a&gt;):&lt;/p&gt;
110
111 &lt;p&gt;&lt;iframe width=&quot;420&quot; height=&quot;315&quot; src=&quot;https://www.youtube.com/embed/N2Kd7CLkhSY&quot; frameborder=&quot;0&quot; allowfullscreen&gt;&lt;/iframe&gt;&lt;/p&gt;
112
113 &lt;p&gt;I mentioned OLSR and batman-adv, which are mesh routing protocols.
114 There are heaps of different protocols, and I am still struggling to
115 figure out which one would be &quot;best&quot; for some definitions of best, but
116 given that the community mesh group in Oslo is so small, I believe it
117 is best to hook up with the existing one instead of trying to create a
118 completely different setup, and thus I have decided to focus on
119 batman-adv for now. It sure help me to know that the very cool
120 &lt;a href=&quot;http://www.servalproject.org/&quot;&gt;Serval project in Australia&lt;/a&gt;
121 is using batman-adv as their meshing technology when it create a self
122 organizing and self healing telephony system for disaster areas and
123 less industrialized communities. Check out this cool video presenting
124 that project (from
125 &lt;a href=&quot;https://www.youtube.com/watch?v=30qNfzJCQOA&quot;&gt;youtube&lt;/a&gt;):&lt;/p&gt;
126
127 &lt;p&gt;&lt;iframe width=&quot;560&quot; height=&quot;315&quot; src=&quot;https://www.youtube.com/embed/30qNfzJCQOA&quot; frameborder=&quot;0&quot; allowfullscreen&gt;&lt;/iframe&gt;&lt;/p&gt;
128
129 &lt;p&gt;According to the wikipedia page on
130 &lt;a href=&quot;http://en.wikipedia.org/wiki/Wireless_mesh_network&quot;&gt;Wireless
131 mesh network&lt;/a&gt; there are around 70 competing schemes for routing
132 packets across mesh networks, and OLSR, B.A.T.M.A.N. and
133 B.A.T.M.A.N. advanced are protocols used by several free software
134 based community mesh networks.&lt;/p&gt;
135
136 &lt;p&gt;The batman-adv protocol is a bit special, as it provide layer 2
137 (as in ethernet ) routing, allowing ipv4 and ipv6 to work on the same
138 network. One way to think about it is that it provide a mesh based
139 vlan you can bridge to or handle like any other vlan connected to your
140 computer. The required drivers are already in the Linux kernel at
141 least since Debian Wheezy, and it is fairly easy to set up. A
142 &lt;a href=&quot;http://www.open-mesh.org/projects/batman-adv/wiki/Quick-start-guide&quot;&gt;good
143 introduction&lt;/a&gt; is available from the Open Mesh project. These are
144 the key settings needed to join the Oslo meshfx network:&lt;/p&gt;
145
146 &lt;p&gt;&lt;table&gt;
147 &lt;tr&gt;&lt;th&gt;Setting&lt;/th&gt;&lt;th&gt;Value&lt;/th&gt;&lt;/tr&gt;
148 &lt;tr&gt;&lt;td&gt;Protocol / kernel module&lt;/td&gt;&lt;td&gt;batman-adv&lt;/td&gt;&lt;/tr&gt;
149 &lt;tr&gt;&lt;td&gt;ESSID&lt;/td&gt;&lt;td&gt;meshfx@hackeriet&lt;/td&gt;&lt;/tr&gt;
150 &lt;td&gt;Channel / Frequency&lt;/td&gt;&lt;td&gt;11 / 2462&lt;/td&gt;&lt;/tr&gt;
151 &lt;td&gt;Cell ID&lt;/td&gt;&lt;td&gt;02:BA:00:00:00:01&lt;/td&gt;
152 &lt;/table&gt;&lt;/p&gt;
153
154 &lt;p&gt;The reason for setting ad-hoc wifi Cell ID is to work around bugs
155 in firmware used in wifi card and wifi drivers. (See a nice post from
156 VillageTelco about
157 &quot;&lt;a href=&quot;http://tiebing.blogspot.no/2009/12/ad-hoc-cell-splitting-re-post-original.html&quot;&gt;Information
158 about cell-id splitting, stuck beacons, and failed IBSS merges!&lt;/a&gt;
159 for details.) When these settings are activated and you have some
160 other mesh node nearby, your computer will be connected to the mesh
161 network and can communicate with any mesh node that is connected to
162 any of the nodes in your network of nodes. :)&lt;/p&gt;
163
164 &lt;p&gt;My initial plan was to reuse my old Linksys WRT54GL as a mesh node,
165 but that seem to be very hard, as I have not been able to locate a
166 firmware supporting batman-adv. If anyone know how to use that old
167 wifi access point with batman-adv these days, please let me know.&lt;/p&gt;
168
169 &lt;p&gt;If you find this project interesting and want to join, please join
170 us on IRC, either channel
171 &lt;a href=&quot;irc://irc.freenode.net/#oslohackerspace&quot;&gt;#oslohackerspace&lt;/a&gt;
172 or &lt;a href=&quot;irc://irc.freenode.net/#nuug&quot;&gt;#nuug&lt;/a&gt; on
173 irc.freenode.net.&lt;/p&gt;
174
175 &lt;p&gt;While investigating mesh networks in Oslo, I came across an old
176 research paper from the university of Stavanger and Telenor Research
177 and Innovation called
178 &lt;a href=&quot;http://folk.uio.no/paalee/publications/netrel-egeland-iswcs-2008.pdf&quot;&gt;The
179 reliability of wireless backhaul mesh networks&lt;/a&gt; and elsewhere
180 learned that Telenor have been experimenting with mesh networks at
181 Grünerløkka in Oslo. So mesh networks are also interesting for
182 commercial companies, even though Telenor discovered that it was hard
183 to figure out a good business plan for mesh networking and as far as I
184 know have closed down the experiment. Perhaps Telenor or others would
185 be interested in a cooperation?&lt;/p&gt;
186
187 &lt;p&gt;&lt;strong&gt;Update 2013-10-12&lt;/strong&gt;: I was just
188 &lt;a href=&quot;http://lists.alioth.debian.org/pipermail/freedombox-discuss/2013-October/005900.html&quot;&gt;told
189 by the Serval project developers&lt;/a&gt; that they no longer use
190 batman-adv (but are compatible with it), but their own crypto based
191 mesh system.&lt;/p&gt;
192 </description>
193 </item>
194
195 <item>
196 <title>Skolelinux / Debian Edu 7.1 install and overview video from Marcelo Salvador</title>
197 <link>http://people.skolelinux.org/pere/blog/Skolelinux___Debian_Edu_7_1_install_and_overview_video_from_Marcelo_Salvador.html</link>
198 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Skolelinux___Debian_Edu_7_1_install_and_overview_video_from_Marcelo_Salvador.html</guid>
199 <pubDate>Tue, 8 Oct 2013 17:10:00 +0200</pubDate>
200 <description>&lt;p&gt;The other day I was pleased and surprised to discover that Marcelo
201 Salvador had published a
202 &lt;a href=&quot;https://www.youtube.com/watch?v=w-GgpdqgLFc&quot;&gt;video on
203 Youtube&lt;/a&gt; showing how to install the standalone Debian Edu /
204 Skolelinux profile. This is the profile intended for use at home or
205 on laptops that should not be integrated into the provided network
206 services (no central home directory, no Kerberos / LDAP directory etc,
207 in other word a single user machine). The result is 11 minutes long,
208 and show some user applications (seem to be rather randomly picked).
209 Missed a few of my favorites like celestia, planets and chromium
210 showing the &lt;a href=&quot;http://www.zygotebody.com/&quot;&gt;Zygote Body 3D model
211 of the human body&lt;/a&gt;, but I guess he did not know about those or find
212 other programs more interesting. :) And the video do not show the
213 advantages I believe is one of the most valuable featuers in Debian
214 Edu, its central school server making it possible to run hundreds of
215 computers without hard drives by installing one central
216 &lt;a href=&quot;http://www.ltsp.org/&quot;&gt;LTSP server&lt;/a&gt;.&lt;/p&gt;
217
218 &lt;p&gt;Anyway, check out the video, embedded below and linked to above:&lt;/p&gt;
219
220 &lt;iframe width=&quot;420&quot; height=&quot;315&quot; src=&quot;http://www.youtube.com/embed/w-GgpdqgLFc&quot; frameborder=&quot;0&quot; allowfullscreen&gt;&lt;/iframe&gt;
221
222 &lt;p&gt;Are there other nice videos demonstrating Skolelinux? Please let
223 me know. :)&lt;/p&gt;
224 </description>
225 </item>
226
227 </channel>
228 </rss>