478 lines
20 KiB
HTML
478 lines
20 KiB
HTML
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
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<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
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<head>
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<!-- 2016-08-30 Tue 12:26 -->
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<meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
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<meta name="viewport" content="width=device-width, initial-scale=1" />
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<title></title>
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<meta name="generator" content="Org-mode" />
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<meta name="author" content="Bob Mottram" />
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<meta name="description" content="Turn the Beaglebone Black into a personal communications server"
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/>
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<meta name="keywords" content="freedombox, debian, beaglebone, red matrix, email, web server, home server, internet, censorship, surveillance, social network, irc, jabber" />
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/* add a generic configuration mode; LaTeX export needs an additional
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#org-div-home-and-up
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{ text-align: right; font-size: 70%; white-space: nowrap; }
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{ font-size: 10px; font-weight: bold; white-space: nowrap; }
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{ background-color: #ffff00; color: #000000; font-weight: bold; }
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/*]]>*/-->
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</style>
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<link rel="stylesheet" type="text/css" href="freedombone.css" />
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<script type="text/javascript">
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/*
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@licstart The following is the entire license notice for the
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JavaScript code in this tag.
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Copyright (C) 2012-2013 Free Software Foundation, Inc.
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The JavaScript code in this tag is free software: you can
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redistribute it and/or modify it under the terms of the GNU
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General Public License (GNU GPL) as published by the Free Software
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Foundation, either version 3 of the License, or (at your option)
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any later version. The code is distributed WITHOUT ANY WARRANTY;
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without even the implied warranty of MERCHANTABILITY or FITNESS
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FOR A PARTICULAR PURPOSE. See the GNU GPL for more details.
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As additional permission under GNU GPL version 3 section 7, you
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may distribute non-source (e.g., minimized or compacted) forms of
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that code without the copy of the GNU GPL normally required by
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section 4, provided you include this license notice and a URL
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through which recipients can access the Corresponding Source.
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@licend The above is the entire license notice
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for the JavaScript code in this tag.
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*/
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<!--/*--><![CDATA[/*><!--*/
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function CodeHighlightOn(elem, id)
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}
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/*]]>*///-->
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</script>
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</head>
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<body>
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<div id="preamble" class="status">
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<a name="top" id="top"></a>
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</div>
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<div id="content">
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<div class="org-center">
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<div class="figure">
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<p><img src="images/logo.png" alt="logo.png" />
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</p>
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</div>
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</div>
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<center><h1>Mesh Network</h1></center>
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<div class="org-center">
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<div class="figure">
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<p><img src="images/mesh_screenshot.jpg" alt="mesh_screenshot.jpg" />
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</p>
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</div>
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</div>
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<p>
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Mesh networks are useful as a quick way to make a fully decentralised communications system which is not connected to or reliant upon the internet. Think festivals, hacker conferences, onboard ships at sea, disaster/war zones, small business internal office communications, protests, remote areas of the world, scientific expeditions and off-world space colonies. All the cool stuff. The down side is that you can't access any internet content. The upside is that you can securely communicate with anyone on the local mesh. No ISPs. No payments or subscriptions beyond the cost of obtaining the hardware. Systems need to be within wifi range of each other for the mesh to be created. It can be an ultra-convenient way to do purely local communications.
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</p>
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<div id="outline-container-orge45c964" class="outline-2">
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<h2 id="orge45c964">Ready made images</h2>
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<div class="outline-text-2" id="text-orge45c964">
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</div><div id="outline-container-org3985b84" class="outline-3">
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<h3 id="org3985b84">Client images</h3>
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<div class="outline-text-3" id="text-org3985b84">
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<p>
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"Client" isn't exactly the right term, but it's a mesh peer with a user interface. These images can be copied to a USB drive, then you can plug it into a laptop/netbook/desktop machine and boot from it. You will probably also need an Atheros USB wifi dongle, because most built-in wifi usually requires proprietary firmware. In the commands below substitute /dev/sdX with the USB drive device, excluding any trailing numbers (eg. /dev/sdb).
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</p>
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<div class="org-src-container">
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<pre class="src src-bash">sudo apt-get install xz-utils wget
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wget https://freedombone.net/downloads/mesh-client-i386.img.xz
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wget https://freedombone.net/downloads/mesh-client-i386.img.xz.sig
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gpg --verify mesh-client-i386.img.xz.sig
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sha256sum mesh-client-i386.img.xz
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eaf87dcbb17b7d8328fde56005d396d423e51390e4163385c0ee8cfa0844d6f3
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unxz mesh-client-i386.img.xz
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sudo dd <span class="org-variable-name">bs</span>=1M <span class="org-variable-name">if</span>=mesh-client-i386.img <span class="org-variable-name">of</span>=/dev/sdX <span class="org-variable-name">conv</span>=fdatasync
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</pre>
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</div>
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<p>
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If you're in an emergency and don't have Atheros wifi dongles then there is also an "insecure" image which contains some proprietary wifi drivers which may work with a wider range of laptops. Proprietary drivers <b>are not recommended</b> because they're unsupportable and may be exploitable or contain malicious antifeatures which fundamentally compromise the security of the network. However, the trade-off between security/maintainability and simply having the ability to communicate at all may be a valid one in some situations.
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</p>
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<div class="org-src-container">
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<pre class="src src-bash">sudo apt-get install xz-utils wget
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wget https://freedombone.net/downloads/mesh-client-i386-insecure.img.xz
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wget https://freedombone.net/downloads/mesh-client-i386-insecure.img.xz.sig
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gpg --verify mesh-client-i386-insecure.img.xz.sig
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sha256sum mesh-client-i386-insecure.img.xz
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2aa1552d695485505b6a145857e5cebb7dc365dbf9614488f474bf5ac1149473
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unxz mesh-client-i386-insecure.img.xz
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sudo dd <span class="org-variable-name">bs</span>=1M <span class="org-variable-name">if</span>=mesh-client-i386-insecure.img <span class="org-variable-name">of</span>=/dev/sdX <span class="org-variable-name">conv</span>=fdatasync
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</pre>
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</div>
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</div>
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</div>
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<div id="outline-container-orgd78876a" class="outline-3">
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<h3 id="orgd78876a">Router images</h3>
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<div class="outline-text-3" id="text-orgd78876a">
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<p>
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Routers are intended to build network coverage for an area using small and low cost hardware. You can bolt them to walls or leave them on window ledges. They don't have any user interface and their only job is to haul network traffic across the mesh. Copy the image to a microSD card and insert it into the router, plug in an Atheros wifi dongle and power on. That should be all you need to do.
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</p>
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</div>
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<div id="outline-container-org24036e7" class="outline-4">
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<h4 id="org24036e7">Beaglebone Black</h4>
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<div class="outline-text-4" id="text-org24036e7">
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<div class="org-src-container">
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<pre class="src src-bash">sudo apt-get install xz-utils wget
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wget https://freedombone.net/downloads/mesh-router-beaglebone-black.img.xz
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wget https://freedombone.net/downloads/mesh-router-beaglebone-black.img.xz.sig
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gpg --verify mesh-router-beaglebone-black.img.xz.sig
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sha256sum mesh-router-beaglebone-black.img.xz
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7e90e0489eff70d7211b2b9b891ba6da20670bedbbe6db3edbb41bc54f7c8679
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unxz mesh-router-beaglebone-black.img.xz
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sudo dd <span class="org-variable-name">bs</span>=1M <span class="org-variable-name">if</span>=mesh-router-beaglebone-black.img <span class="org-variable-name">of</span>=/dev/sdX <span class="org-variable-name">conv</span>=fdatasync
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</pre>
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</div>
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</div>
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</div>
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</div>
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</div>
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<div id="outline-container-orgae92e8f" class="outline-2">
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<h2 id="orgae92e8f">To build the disk image yourself</h2>
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<div class="outline-text-2" id="text-orgae92e8f">
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<p>
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It's better not to trust images downloaded from random places on the interwebs. Chances are that unless you are in the web of trust of the above GPG signatures then they don't mean very much to you. If you actually want something trustworthy then build the images from scratch. It will take some time. Here's how to do it.
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</p>
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<p>
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First you will need to create an image. On a Debian based system:
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</p>
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<div class="org-src-container">
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<pre class="src src-bash">sudo su
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apt-get -y install build-essential libc6-dev-i386 <span class="org-sh-escaped-newline">\</span>
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gcc-multilib g++-multilib git python-docutils mktorrent <span class="org-sh-escaped-newline">\</span>
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vmdebootstrap xz-utils dosfstools btrfs-tools extlinux <span class="org-sh-escaped-newline">\</span>
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python-distro-info mbr qemu-user-static binfmt-support <span class="org-sh-escaped-newline">\</span>
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u-boot-tools qemu
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git clone https://github.com/bashrc/freedombone
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<span class="org-builtin">cd</span> freedombone
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git checkout stockholm
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make install
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freedombone-image -t i386 -v meshclient
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</pre>
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</div>
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<p>
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If you don't have Atheros or free software compatible wifi adapter then you can include proprietary wifi drivers which will work with most laptops. This is <b>NOT RECOMMENDED</b> because proprietary drivers are unsupportable and may contain either malware or be exploitable in a way which can't be fixed. However, if you're in an emergency and don't have any Atheros or free software wifi USB dongles then you can use the following command to make the image:
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</p>
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<div class="org-src-container">
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<pre class="src src-bash">freedombone-image -t i386 -v meshclient --insecure yes
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</pre>
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</div>
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<p>
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This takes a while. Maybe an hour or so, depending on the speed of your system and the internets. The good news though is that once created you can use the resulting image any number of times, and you don't need to trust some pre-built image.
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</p>
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<p>
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List what drives are on your system with:
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</p>
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<div class="org-src-container">
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<pre class="src src-bash">ls /dev/sd*
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</pre>
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</div>
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<p>
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Now plug in the USB thumb drive, and do the same again. Notice which drive letter gets added.
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</p>
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<p>
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You can now copy the image to the USB thumb drive, replacing <b>sdX</b> with the identifier of the USB thumb drive. Don't include any numbers (so for example use <b>sdc</b> instead of <b>sdc1</b>).
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</p>
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<div class="org-src-container">
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|
<pre class="src src-bash">dd <span class="org-variable-name">bs</span>=1M <span class="org-variable-name">if</span>=myimagefile.img <span class="org-variable-name">of</span>=/dev/sdX <span class="org-variable-name">conv</span>=fdatasync
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</pre>
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</div>
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<p>
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|
And wait. Again it will take a while to copy over. When that's done plug it into the laptop or netbook which you want to use on the mesh, power on and set the BIOS to boot from the USB stick.
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|
</p>
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|
|
|
<p>
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|
On first boot you'll be asked to set a username, and then you can open the chat client and select the <b>users</b> icon to show the Tox IDs for other users on the mesh. When folks join they will be announced.
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|
</p>
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|
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|
<p>
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|
Rinse, repeat, for any number of laptops that you want to get onto the mesh or to build out coverage within an area. There are no servers. Just peer-to-peer communications routed through the network which are end-to-end secure after a friend request is accepted. By default the chat client doesn't log anything.
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|
</p>
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|
|
|
<p>
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|
<b>No logs, no masters.</b>
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|
</p>
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|
|
|
<p>
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|
You can also use single board computers (SBCs) such as the BeagleBone Black to make mesh routers which can be bolted to walls or the sides of buildings and consume minimal electrical power, so could be solar or battery powered for short term events such as festivals. To do that use the following command to make the image:
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|
</p>
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|
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|
<div class="org-src-container">
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|
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|
<pre class="src src-bash">freedombone-image -t beaglebone -v mesh
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|
</pre>
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|
</div>
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|
|
|
<p>
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|
The resulting image can be copied to a microSD card, inserted into a Beaglebone Black and booted. Don't forget to plug in an Atheros USB wifi dongle.
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|
</p>
|
|
</div>
|
|
</div>
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|
|
|
<div id="outline-container-orge48cc64" class="outline-2">
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|
<h2 id="orge48cc64">How to use it</h2>
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|
<div class="outline-text-2" id="text-orge48cc64">
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|
<p>
|
|
When you first boot from the USB drive the system will create some encryption keys, assign a unique network address to the system and then reboot itself. When that's done you should see a prompt asking for a username. This username just makes it easy for others to initially find you on the mesh and will appear in the list of users.
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|
</p>
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|
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|
<p>
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|
Ensure that you're within wifi range of at least one other mesh peer (could be a router or client) and then you should see that the Tox chat and users icons appear. Select the users icon and you should see a list of users on the mesh. Select the Tox chat icon and once you are connected you should see the status light turn green. If after a few minutes you don't get the green status light then try closing and re-opening the Tox chat application. Select the plus button to add a friend and then copy and paste in a Tox ID from the users list. The other user can then accept or decline your friend request.
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|
</p>
|
|
|
|
<p>
|
|
One important point is that by default sound and microphone is turned off. In the top right corner of the screen you can increase the sound volume and enable the microphone if you're doing voice chat.
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|
</p>
|
|
|
|
<p>
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|
At present video doesn't work reliably, but text and voice chat do work well. In future IPFS or Tahoe-LAFS may be added to create a distributed filesystem for the mesh.
|
|
</p>
|
|
|
|
|
|
<div class="org-center">
|
|
<p>
|
|
This site can also be accessed via a Tor browser at <a href="http://4fvfozz6g3zmvf76.onion/">4fvfozz6g3zmvf76.onion</a>
|
|
</p>
|
|
</div>
|
|
</div>
|
|
</div>
|
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</div>
|
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<div id="postamble" class="status">
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<style type="text/css">
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.back-to-top {
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position: fixed;
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bottom: 2em;
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right: 0px;
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text-decoration: none;
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color: #000000;
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background-color: rgba(235, 235, 235, 0.80);
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font-size: 12px;
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padding: 1em;
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display: none;
|
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}
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.back-to-top:hover {
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background-color: rgba(135, 135, 135, 0.50);
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|
}
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</style>
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<div class="back-to-top">
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<a href="#top">Back to top</a> | <a href="mailto:bob@robotics.uk.to">E-mail me</a>
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