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@ -1,763 +0,0 @@ |
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Title: How to Build a Low-tech Internet |
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Author: Kris de Decker |
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<!-- Status: published --> |
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<p id="colophon_title">Colophon</p> |
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<div class="colophon"> |
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<p>A Nourishing Network is a peer-to-peer publishing experiment starting from the feed as a potentially multi-directional circulation device.</p> |
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<p>A Nourishing Network is initiated by servus.at (Davide Bevilacqua) in collaboration with varia.zone (Alice Strete & Manetta Berends) and is published in the context of AMRO 2020 (Arts Meets Radical Openness). </p> |
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<p> Editing: Davide Bevilacqua <br> Design and development: Manetta Berends, Alice Strete <br> Paper: xxxx <br> Typeface: Gnu Unifont, White Rabbit, Ansi Shadow <br> Print and production: Varia <br> This project is produced with Free Software tools. The feeds are made with Pelican & Weasyprint. |
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</p> |
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<p> Davide is an artist and curator working is the blurry area between media and contemporary art. </p><p> Manetta Berends is a designer working with forms of networked publishing, situated software and collective infrastructures. </p> <p>Alice Strete is an artist and researcher interested in the intricate relationship between humans and the technologies they surround themselves with. </p> <p>Many thanks to our partners, collaborators, authors and the AMRO community. </p> |
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<p> Published under the CC-BY-SA 4.0 license.</p> |
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</p></div> |
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<div class="first-page"> |
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<div id="title_edition"> A Nourishing Network - December 2020</div> |
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<div id="title">The Philosophy of Warnings</div> |
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<div id="author"> by Santiago Zabala</div> |
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<pre id="ascii_blob"> |
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----------------------------------a----------------------------------- |
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-------------------------- - - - - - ----------------------------- |
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----------------------n--n--n--n--n--n--n--n--n----------------------- |
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--------------------o----o---o----o----o---o----o--------------------- |
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----------------u-----u-----u-----u-----u-----u-----u----------------- |
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-------------r------r------r------r------r------r------r-------------- |
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----------i-------i-------i-------i-------i-------i-------i----------- |
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-------s--------s--------s--------s--------s--------s--------s-------- |
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-----h---------h--------h---------h---------h--------h---------h------ |
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----i---------i---------i---------i---------i---------i---------i----- |
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----n---------n---------n---------n---------n---------n---------n----- |
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----g---------g---------g---------g---------g---------g---------g----- |
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----- --------- -------- --------- --------- -------- --------- ------ |
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-------n--------n--------n--------n--------n--------n--------n-------- |
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----------e-------e-------e-------e-------e-------e-------e----------- |
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-------------t------t------t------t------t------t------t-------------- |
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----------------w-----w-----w-----w-----w-----w-----w----------------- |
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--------------------o----o---o----o----o---o----o--------------------- |
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-------------------------r--r--r--r--r--r--r-------------------------- |
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---------------------------- k-kk-k-kk-k ----------------------------- |
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</pre> |
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</div> |
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<header id="pageheader-issue">A Nourishing Network</header> |
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<header id="pageheader-theme">The Philosophy of Warnings</header> |
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<div class="essay_content"> |
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<p> |
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Wireless internet access is on the rise in both modern consumer |
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societies and in the developing world.</p> |
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In rich countries, however, the focus is on always-on connectivity and |
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ever higher access speeds. In poor countries, on the other hand, |
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connectivity is achieved through much more low-tech, often asynchronous |
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networks. |
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While the high-tech approach pushes the costs and energy use of the |
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internet [higher and higher](https://www.lowtechmagazine.com/2015/10/can-the-internet-run-on-renewable-energy.html), |
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the low-tech alternatives result in much cheaper and very energy |
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efficient networks that combine well with renewable power production and |
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are resistant to disruptions. |
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If we want the internet to keep working in circumstances where access to |
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energy is more limited, we can learn important lessons from alternative |
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network technologies. Best of all, there\'s no need to wait for |
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governments or companies to facilitate: we can build our own resilient |
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communication infrastructure if we cooperate with one another. This is |
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demonstrated by several community networks in Europe, of which the |
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largest has more than 35,000 users already. |
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[]{#anchor}Picture: A node in the [Scottish Tegola |
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Network](http://www.tegola.org.uk/hebnet/). |
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More than half of the global population does not have access to the |
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\"worldwide\" web. Up to now, the internet is mainly an urban |
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phenomenon, especially in \"developing\" countries. Telecommunication |
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companies are usually reluctant to extend their network outside cities |
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due to a combination of high infrastructure costs, low population |
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density, limited ability to pay for services, and an unreliable or |
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non-existent electricity infrastructure. Even in remote regions of |
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\"developed\" countries, internet connectivity isn\'t always available. |
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Internet companies such as Facebook and Google regularly make headlines |
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with plans for connecting these remote regions to the internet. Facebook |
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tries to achieve this with drones, while Google counts on high-altitude |
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balloons. There are major technological challenges, but the main |
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objection to these plans is their commercial character. Obviously, |
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Google and Facebook want to connect more people to the internet because |
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that would increase their revenues. Facebook especially receives lots of |
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criticism because their network promotes their own site in particular, |
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and blocks most other internet applications. \[1\] |
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Meanwhile, several research groups and network enthusiasts have |
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developed and implemented much cheaper alternative network technologies |
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to solve these issues. Although these low-tech networks have proven |
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their worth, they have received much less attention. Contrary to the |
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projects of internet companies, they are set up by small organisations |
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or by the users themselves. This guarantees an open network that |
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benefits the users instead of a handful of corporations. At the same |
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time, these low-tech networks are very energy efficient. |
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****WiFi-based Long Distance Networks**** |
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Most low-tech networks are based on WiFi, the same technology that |
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allows mobile access to the internet in most western households. As we |
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have seen in the previous article, [sharing these devices could provide |
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free mobile access across densely populated |
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cities](https://www.lowtechmagazine.com/2015/10/the-4g-network-thats-already-there.html). |
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But the technology can be equally useful in sparsely populated areas. |
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Although the WiFi-standard was developed for short-distance data |
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communication (with a typical range of about 30 metres), its reach can |
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be extended through modifications of the Media Access Control (MAC) |
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layer in the networking protocol, and through the use of range extender |
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amplifiers and directional antennas. \[2\] |
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Although the WiFi-standard was developed for short-distance data |
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communication, its reach can be extended to cover distances of more than |
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100 kilometres. |
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The longest unamplified WiFi link is a 384 km wireless point-to-point |
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connection between Pico El Águila and Platillón in Venezuela, |
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established a few years ago. \[3,4\] However, WiFi-based long distance |
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networks usually consist of a combination of shorter point-to-point |
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links, each between a few kilometres and one hundred kilometers long at |
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most. These are combined to create larger, multihop networks. |
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Point-to-points links, which form the backbone of a long range WiFi |
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network, are combined with omnidirectional antennas that distribute the |
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signal to individual households (or public institutions) of a community. |
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Picture: A relay with three point-to-point links and three sectoral |
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antennae. |
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[Tegola](http://www.tegola.org.uk/howto/network-planning.html). |
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Long-distance WiFi links require line of sight to make a connection \-- |
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in this sense, the technology resembles the [18th century optical |
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telegraph](https://www.lowtechmagazine.com/2007/12/email-in-the-18.html). |
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\[5\] If there\'s no line of sight between two points, a third relay is |
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required that can see both points, and the signal is sent to the |
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intermediate relay first. Depending on the terrain and particular |
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obstacles, more hubs may be necessary. \[6\] |
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Point-to-point links typically consist of two directional antennas, one |
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focused on the next node and the other on the previous node in the |
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network. Nodes can have multiple antennas with one antenna per fixed |
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point-to-point link to each neighbour. \[7\] This allows mesh routing |
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protocols that can dynamically select which links to choose for routing |
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among the available ones. \[8\] |
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Long-distance WiFi links require line of sight to make a connection \-- |
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in this sense, the technology resembles the 18th century optical |
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telegraph. |
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Distribution nodes usually consist of a sectoral antenna (a small |
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version of the things you see on mobile phone masts) or a conventional |
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WiFi-router, together with a number of receivers in the community. \[6\] |
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For short distance WiFi-communication, there is no requirement for line |
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of sight between the transmitter and the receiver. \[9\] |
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To provide users with access to the worldwide internet, a long range |
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WiFi network should be connected to the main backbone of the internet |
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using at least one \"backhaul\" or \"gateway node\". This can be a |
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dial-up or broadband connection (DSL, fibre or satellite). If such a |
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link is not established, users would still be able to communicate with |
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each other and view websites set up on local servers, but they would not |
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be able to access the internet. \[10\] |
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****Advantages of Long Range WiFi**** |
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Long range WiFi offers high bandwidth (up to 54 Mbps) combined with very |
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low capital costs. Because the WiFi standard enjoys widespread |
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acceptance and has huge production volumes, off-the-shelf antennas and |
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wireless cards can be bought for very little money. \[11\] |
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Alternatively, components can be put together [from discarded |
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materials](http://roelof.info/projects/%282014%29Pretty_Fly_For_A_Wifi/) |
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such as old routers, satellite dish antennas and laptops. Protocols like |
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WiLDNet run on a 266 Mhz processor with only 128 MB memory, so an old |
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computer will do the trick. \[7\] |
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The WiFi-nodes are lightweight and don\'t need expensive towers \-- |
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further decreasing capital costs, and minimizing the impact of the |
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structures to be built. \[7\] More recently, single units that combine |
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antenna, wireless card and processor have become available. These are |
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very convenient for installation. To build a relay, one simply connects |
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such units together with ethernet cables that carry both signal and |
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power. \[6\] The units can be mounted in towers or slim masts, given |
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that they offer little windload. \[3\] Examples of suppliers of long |
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range WiFi components are [Ubiquity](https://www.ubnt.com/), |
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[Alvarion](http://www.alvarion.com/) and |
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[MikroTik](http://www.mikrotik.com/), and |
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[simpleWiFi](https://www.simplewifi.com/). |
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Long Range WiFi makes use of unlicensed spectrum and offers high |
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bandwidth, low capital costs, easy installation, and low power |
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requirements. |
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Long range WiFi also has low operational costs due to low power |
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requirements. A typical mast installation consisting of two long |
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distance links and one or two wireless cards for local distribution |
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consumes around 30 watts. \[6,12\] In several low-tech networks, nodes |
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are entirely powered by solar panels and batteries. Another important |
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advantage of long range WiFi is that it makes use of unlicensed spectrum |
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(2.4 and 5 GHz), and thus avoids negotiations with telecom operators and |
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government. This adds to the cost advantage and allows basically anyone |
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to start a WiFi-based long distance network. \[9\] |
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****Long Range WiFi Networks in Poor Countries**** |
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The first long range WiFi networks were set up ten to fifteen years ago. |
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In poor countries, two main types have been built. The first is aimed at |
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providing internet access to people in remote villages. An example is |
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the Akshaya network in India, which covers the entire Kerala State and |
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is one of the largest wireless networks in the world. The infrastructure |
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is built around approximately 2,500 \"computer access centers\", which |
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are open to the local population \-- direct ownership of computers is |
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minimal in the region. \[13\] |
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Another example, also in India, are the AirJaldi networks which provide |
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internet access to approximately 20,000 users in six states, all in |
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remote regions and on difficult terrain. Most nodes in this network are |
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solar-powered and the distance between them can range up to 50 km or |
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more. \[14\] In some African countries, local WiFi-networks distribute |
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internet access from a satellite gateway. \[15,16\] |
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A node in the AirJaldi network. Picture: AirJaldi. |
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A second type of long distance WiFi network in poor countries is aimed |
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at providing telemedicine to remote communities. In remote regions, |
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health care is often provided through health posts scarcely equipped and |
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attended by health technicians who are barely trained. \[17\] Long-range |
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WiFi networks can connect urban hospitals with these outlying health |
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posts, allowing doctors to remotely support health technicians using |
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high-resolution file transfers and real-time communication tools based |
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on voice and video. |
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An example is the link between Cabo Pantoja and Iquitos in the Loreto |
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province in Peru, which was established in 2007. The 450 km network |
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consists of 17 towers which are 16 to 50 km apart. The line connects 15 |
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medical outposts in remote villages with the main hospital in Iquitos |
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and is aimed at remote diagnosis of patients. \[17,18\] All equipment is |
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powered by solar panels. \[18,19\] Other succesful examples of long |
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range WiFi telemedicine networks have been built in India, Malawi and |
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Ghana. \[20,21\] |
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****WiFi-Based Community Networks in Europe**** |
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The low-tech networks in poor countries are set up by NGO\'s, |
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governments, universities or businesses. In contrast, most of the |
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WiFi-based long distance networks in remote regions of rich countries |
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are so-called \"community networks\": the users themselves build, own, |
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power and maintain the infrastructure. Similar to the shared wireless |
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approach in cities, reciprocal resource sharing forms the basis of these |
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networks: participants can set up their own node and connect to the |
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network (for free), as long as their node also allows traffic of other |
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members. Each node acts as a WiFi routing device that provides IP |
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forwarding services and a data link to all users and nodes connected to |
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it. \[8,22\] |
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In a community network, the users themselves build, own, power and |
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maintain the infrastructure. |
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Consequently, with each new user, the network becomes larger. There is |
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no a-priori overall planning. A community network grows bottom-up, |
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driven by the needs of its users, as nodes and links are added or |
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upgraded following demand patterns. The only consideration is to connect |
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a node from a new participant to an existing one. As a node is powered |
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on, it discovers it neighbours, attributes itself a unique IP adress, |
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and then establishes the most appropriate routes to the rest of the |
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network, taking into account the quality of the links. Community |
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networks are open to participation to everyone, sometimes according to |
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an open peering agreement. \[8,9,19,22\] |
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Wireless links in the Spanish Guifi network. |
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[Credit](https://iuliinet.github.io/presentazione_ottobre_2014/img/barcellona.jpg). |
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Despite the lack of reliable statistics, community networks seem to be |
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rather succesful, and there are several large ones in Europe, such as |
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[Guifi.net](https://guifi.net/) (Spain), [Athens Wireless Metropolitan |
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Network](http://www.awmn.gr/content.php?s=ce506a41ab245641d6934638c6f6f107) |
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(Greece), [FunkFeuer](http://www.funkfeuer.at/) (Austria), and |
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[Freifunk](https://freifunk.net/en/) (Germany). \[8,22,23,24\] The |
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Spanish network is the largest WiFi-based long distance network in the |
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world with more than 50,000 kilometres of links, although a small part |
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is based on optic fibre links. Most of it is located in the Catalan |
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Pyrenees, one of the least populated areas in Spain. The network was |
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initiated in 2004 and now has close to 30,000 nodes, up from 17,000 in |
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2012. \[8,22\] |
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Guifi.net provides internet access to individuals, companies, |
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administrations and universities. In principle, the network is |
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installed, powered and maintained by its users, although volunteer teams |
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and even commercial installers are present to help. Some nodes and |
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backbone upgrades have been succesfully crowdfunded by indirect |
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beneficiaries of the network. \[8,22\] |
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****Performance of Low-tech Networks**** |
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So how about the performance of low-tech networks? What can you do with |
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them? The available bandwidth per user can vary enormously, depending on |
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the bandwidth of the gateway node(s) and the number of users, among |
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other factors. The long-distance WiFi networks aimed at telemedicine in |
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poor countries have few users and a good backhaul, resulting in high |
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bandwidth (+ 40 Mbps). This gives them a similar performance to fibre |
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connections in the developed world. A study of (a small part of) the |
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Guifi.net community network, which has dozens of gateway nodes and |
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thousands of users, showed an average throughput of 2 Mbps, which is |
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comparable to a relatively slow DSL connection. Actual throughput per |
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user varies from 700 kbps to 8 Mbps. \[25\] |
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The available bandwidth per user can vary enormously, depending on the |
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bandwidth of the gateway node(s) and the number of users, among other |
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factors |
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However, the low-tech networks that distribute internet access to a |
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large user base in developing countries can have much more limited |
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bandwidth per user. For example, a university campus in Kerala (India) |
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uses a 750 kbps internet connection that is shared across 3,000 faculty |
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members and students operating from 400 machines, where during peak |
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hours nearly every machine is being used. |
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Therefore, the worst-case average bandwidth available per machine is |
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approximately 1.9 kbps, which is slow even in comparison to a dial-up |
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connection (56 kbps). And this can be considered a really good |
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connectivity compared to typical rural settings in poor countries. |
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\[26\] To make matters worse, such networks often have to deal with an |
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intermittent power supply. |
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Under these circumstances, even the most common internet applications |
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have poor performance, or don\'t work at all. The communication model of |
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the internet is based on a set of network assumptions, called the TCP/IP |
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protocol suite. These include the existence of a bi-directional |
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end-to-end path between the source (for example a website\'s server) and |
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the destination (the user\'s computer), short round-trip delays, and low |
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error rates. |
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Many low-tech networks in poor countries do not comform to these |
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|
assumptions. They are characterized by intermittent connectivity or |
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|
\"network partitioning\" \-- the absence of an end-to-end path between |
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|
source and destination \-- long and variable delays, and high error |
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|
rates. \[21,27,28\] |
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|
****Delay-Tolerant Networks**** |
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|
Nevertheless, even in such conditions, the internet could work perfectly |
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|
fine. The technical issues can be solved by moving away from the |
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|
always-on model of traditional networks, and instead design networks |
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|
based upon asynchronous communication and intermittent connectivity. |
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|
These so-called \"delay-tolerant networks\" (DTNs) have their own |
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|
specialized protocols overlayed on top of the lower protocols and do not |
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|
utilize TCP. They overcome the problems of intermittent connectivity and |
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|
long delays by using store-and-forward message switching. |
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|
Information is forwarded from a storage place on one node to a storage |
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|
place on another node, along a path that *eventually* reaches its |
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|
destination. In contrast to traditional internet routers, which only |
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|
store incoming packets for a few milliseconds on memory chips, the nodes |
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|
of a delay-tolerant network have persistent storage (such as hard disks) |
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|
that can hold information indefinitely. \[27,28\] |
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Delay-tolerant networks combine well with renewable energy: solar panels |
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|
or wind turbines could power network nodes only when the sun shines or |
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|
the wind blows, eliminating the need for energy storage. |
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|
Delay-tolerant networks don\'t require an end-to-end path between source |
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|
and destination. Data is simply transferred from node to node. If the |
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|
next node is unavailable because of long delays or a power outage, the |
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|
data is stored on the hard disk until the node becomes available again. |
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|
While it might take a long time for data to travel from source to |
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|
destination, a delay-tolerant network ensures that it will eventually |
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|
arrive. |
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|
Delay-tolerant networks further decrease capital costs and energy use, |
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|
leading to the most efficient use of scarce resources. They keep working |
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|
with an intermittent energy supply and they combine well with renewable |
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|
energy sources: solar panels or wind turbines could power network nodes |
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|
only when the sun shines or the wind blows, eliminating the need for |
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|
energy storage. |
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|
****Data Mules**** |
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|
Delay-tolerant networking can take surprising forms, especially when |
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|
they take advantage of some non-traditional means of communication, such |
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|
as \"data mules\". \[11,29\] In such networks, conventional |
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|
transportation technologies \-- buses, cars, motorcycles, trains, boats, |
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|
airplanes \-- are used to ferry messages from one location to another in |
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|
a store-and-forward manner. |
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Examples are DakNet and KioskNet, which use buses as data mules. |
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|
\[30-34\] In many developing regions, rural bus routes regularly visit |
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|
villages and towns that have no network connectivity. By equipping each |
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|
vehicle with a computer, a storage device and a mobile WiFi-node on the |
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|
one hand, and by installing a stationary WiFi-node in each village on |
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|
the other hand, the local transport infrastructure can substitute for a |
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|
wireless internet link. \[11\] |
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|
Picture: AirJaldi. |
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|
Outgoing data (such as sent emails or requests for webpages) is stored |
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|
on local computers in the village until the bus comes withing range. At |
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|
this point, the fixed WiFi-node of the local computer automatically |
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|
transmits the data to the mobile WiFi-node of the bus. Later, when the |
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|
bus arrives at a hub that is connected to the internet, the outgoing |
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|
data is transmitted from the mobile WiFi-node to the gateway node, and |
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|
then to the internet. Data sent to the village takes the opposite route. |
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|
The bus \-- or data \-- driver doesn\'t require any special skills and |
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|
is completely oblivious to the data transfers taking place. He or she |
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|
does not need to do anything other than come in range of the nodes. |
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|
\[30,31\] |
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|
In a data mules network, the local transport infrastructure substitutes |
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|
for a wireless internet link. |
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|
The use of data mules offers some extra advantages over more |
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|
|
\"sophisticated\" delay-tolerant networks. A \"drive-by\" WiFi network |
|
|
|
allows for small, low-cost and low-power radio devices to be used, which |
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|
don\'t require line of sight and consequently no towers \-- further |
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|
|
lowering capital costs and energy use compared to other low-tech |
|
|
|
networks. \[30,31,32\] |
|
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|
The use of short-distance WiFi-links also results in a higher bandwidth |
|
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|
compared to long-distance WiFi-links, which makes data mules better |
|
|
|
suited to transfer larger files. On average, 20 MB of data can be moved |
|
|
|
in each direction when a bus passes a fixed WiFi-node. \[30,32\] On the |
|
|
|
other hand, latency (the time interval between sending and receiving |
|
|
|
data) is usually higher than on long-range WiFi-links. A single bus |
|
|
|
passing by a village once a day gives a latency of 24 hours. |
|
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|
|
|
|
****Delay-Tolerant Software**** |
|
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|
Obviously, a delay-tolerant network (DTN) \-- whatever its form \-- also |
|
|
|
requires new software: applications that function without a connected |
|
|
|
end-to-end networking path. \[11\] Such custom applications are also |
|
|
|
useful for synchronous, low bandwidth networks. Email is relatively easy |
|
|
|
to adapt to intermittent connectivity, because it\'s an asynchronous |
|
|
|
communication method by itself. A DTN-enabled email client stores |
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|
|
outgoing messages until a connection is available. Although emails may |
|
|
|
take longer to reach their destination, the user experience doesn\'t |
|
|
|
really change. |
|
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|
|
|
|
|
A Freifunk WiFi-node is installed in Berlin, Germany. Picture:[ |
|
|
|
Wikipedia |
|
|
|
Commons](https://upload.wikimedia.org/wikipedia/commons/5/51/Freifunk-Initiative_in_Berlin-Kreuzberg.jpg). |
|
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|
|
Browsing and searching the web requires more adaptations. For example, |
|
|
|
most search engines optimize for speed, assuming that a user can quickly |
|
|
|
look through the returned links and immediately run a second modified |
|
|
|
search if the first result is inadequate. However, in intermittent |
|
|
|
networks, multiple rounds of interactive search would be impractical. |
|
|
|
\[26,35\] Asynchronous search engines optimize for bandwith rather than |
|
|
|
response time. \[26,30,31,35,36\] For example, RuralCafe desynchronizes |
|
|
|
the search process by performing many search tasks in an offline manner, |
|
|
|
refining the search request based on a database of similar searches. The |
|
|
|
actual retrieval of information using the network is only done when |
|
|
|
absolutely necessary. |
|
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|
|
|
|
Many internet applications could be adapted to intermittent networks, |
|
|
|
such as webbrowsing, email, electronic form filling, interaction with |
|
|
|
e-commerce sites, blogsoftware, large file downloads, or social media. |
|
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|
|
|
|
Some DTN-enabled browsers download not only the explicitly requested |
|
|
|
webpages but also the pages that are linked to by the requested pages. |
|
|
|
\[30\] Others are optimized to return low-bandwidth results, which are |
|
|
|
achieved by filtering, analysis, and compression on the server site. A |
|
|
|
similar effect can be achieved through the use of a service like |
|
|
|
[Loband](http://www.loband.org/loband/), which strips webpages of |
|
|
|
images, video, advertisements, social media buttons, and so on, merely |
|
|
|
presenting the textual content. \[26\] |
|
|
|
|
|
|
|
Browsing and searching on intermittent networks can also be improved by |
|
|
|
local caching (storing already downloaded pages) and prefetching |
|
|
|
(downloading pages that might be retrieved in the future). \[206\] Many |
|
|
|
other internet applications could also be adapted to intermittent |
|
|
|
networks, such as electronic form filling, interaction with e-commerce |
|
|
|
sites, blogsoftware, large file downloads, social media, and so on. |
|
|
|
\[11,30\] All these applications would remain possible, though at lower |
|
|
|
speeds. |
|
|
|
|
|
|
|
****Sneakernets**** |
|
|
|
|
|
|
|
Obviously, real-time applications such as internet telephony, media |
|
|
|
streaming, chatting or videoconferencing are impossible to adapt to |
|
|
|
intermittent networks, which provide only asynchronous communication. |
|
|
|
These applications are also difficult to run on synchronous networks |
|
|
|
that have limited bandwidth. Because these are the applications that are |
|
|
|
in large part responsible for the growing energy use of the internet, |
|
|
|
one could argue that their incompatibility with low-tech networks is |
|
|
|
actually a good thing (see the [previous |
|
|
|
article](https://www.lowtechmagazine.com/2015/10/can-the-internet-run-on-renewable-energy.html)). |
|
|
|
|
|
|
|
Furthermore, many of these applications could be organized in different |
|
|
|
ways. While real-time voice or video conversations won\'t work, it\'s |
|
|
|
perfectly possible to send and receive voice or video messages. And |
|
|
|
while streaming media can\'t happen, downloading music albums and video |
|
|
|
remains possible. Moreover, these files could be \"transmitted\" by the |
|
|
|
most low-tech internet technology available: a sneakernet. In a |
|
|
|
sneakernet, digital data is \"wirelessly\" transmitted using a storage |
|
|
|
medium such as a hard disk, a USB-key, a flash card, or a CD or DVD. |
|
|
|
Before the arrival of the internet, all computer files were exchanged |
|
|
|
via a sneakernet, using tape or floppy disks as a storage medium. |
|
|
|
|
|
|
|
Stuffing a cargo train full of digital storage media would beat any |
|
|
|
digital network in terms of speed, cost and energy efficiency. Picture: |
|
|
|
Wikipedia Commons. |
|
|
|
|
|
|
|
Just like a data mules network, a sneakernet involves a vehicle, a |
|
|
|
messenger on foot, or an animal (such as a [carrier |
|
|
|
pigeon](https://www.lowtechmagazine.com/2009/02/sneakernet-beats-internet.html)). |
|
|
|
However, in a sneakernet there is no automatic data transfer between the |
|
|
|
mobile node (for instance, a vehicle) and the stationary nodes (sender |
|
|
|
and recipient). Instead, the data first have to be transferred from the |
|
|
|
sender\'s computer to a portable storage medium. Then, upon arrival, the |
|
|
|
data have to be transferred from the portable storage medium to the |
|
|
|
receiver\'s computer. \[30\] A sneakernet thus requires manual |
|
|
|
intervention and this makes it less convenient for many internet |
|
|
|
applications. |
|
|
|
|
|
|
|
There are exceptions, though. For example, a movie doesn\'t have to be |
|
|
|
transferred to the hard disk of your computer in order to watch it. You |
|
|
|
play it straight from a portable hard disk or slide a disc into the |
|
|
|
DVD-player. Moreover, a sneakernet also offers an important advantage: |
|
|
|
of all low-tech networks, it has the most bandwidth available. This |
|
|
|
makes it perfectly suited for the distribution of large files such as |
|
|
|
movies or computer games. In fact, when very large files are involved, a |
|
|
|
sneakernet even beats the fastest fibre internet connection. At lower |
|
|
|
internet speeds, sneakernets can be advantageous for much smaller files. |
|
|
|
|
|
|
|
Technological progress will not lower the advantage of a sneakernet. |
|
|
|
Digital storage media evolve at least as fast as internet connections |
|
|
|
and they both improve communication in an equal way. |
|
|
|
|
|
|
|
****Resilient Networks**** |
|
|
|
|
|
|
|
While most low-tech networks are aimed at regions where the alternative |
|
|
|
is often no internet connection at all, their usefulness for |
|
|
|
well-connected areas cannot be overlooked. The internet as we know it in |
|
|
|
the industrialized world is a product of an abundant energy supply, a |
|
|
|
robust electricity infrastructure, and sustained economic growth. This |
|
|
|
\"high-tech\" internet might offer some fancy advantages over the |
|
|
|
low-tech networks, but it cannot survive if these conditions change. |
|
|
|
This makes it extremely vulnerable. |
|
|
|
|
|
|
|
The internet as we know it in the industrialized world is a product of |
|
|
|
an abundant energy supply, a robust electricity infrastructure, and |
|
|
|
sustained economic growth. It cannot survive if these conditions change. |
|
|
|
|
|
|
|
Depending on their level of resilience, low-tech networks can remain in |
|
|
|
operation when the supply of fossil fuels is interrupted, when the |
|
|
|
electricity infrastructure deteriorates, when the economy grinds to a |
|
|
|
halt, or if other calamities should hit. Such a low-tech internet would |
|
|
|
allow us to surf the web, send and receive e-mails, shop online, share |
|
|
|
content, and so on. Meanwhile, data mules and sneakernets could serve to |
|
|
|
handle the distribution of large files such as videos. Stuffing a cargo |
|
|
|
vessel or a train full of digital storage media would beat any digital |
|
|
|
network in terms of speed, cost and energy efficiency. And if such a |
|
|
|
transport infrastructure would no longer be available, we could still |
|
|
|
rely on messengers on foot, [cargo |
|
|
|
bikes](https://www.lowtechmagazine.com/2014/05/modular-cargo-cycles.html) |
|
|
|
and [sailing vessels](https://www.lowtechmagazine.com/sailing-ships/). |
|
|
|
|
|
|
|
Such a hybrid system of online and offline applications would remain a |
|
|
|
very powerful communication network \-- unlike anything we had even in |
|
|
|
the late twentieth century. Even if we envision a doom scenario in which |
|
|
|
the wider internet infrastructure would disintegrate, isolated low-tech |
|
|
|
networks would still be very useful local and regional communication |
|
|
|
technologies. Furthermore, they could obtain content from other remote |
|
|
|
networks through the exchange of portable storage media. The internet, |
|
|
|
it appears, can be as low-tech or high-tech as we can afford it to be. |
|
|
|
</div> |
|
|
|
Kris De Decker (edited by [Jenna |
|
|
|
Collett](https://www.linkedin.com/pub/jenna-collett/1a/925/b3)) |
|
|
|
|
|
|
|
This article has been translated into |
|
|
|
[Spanish](https://solar.lowtechmagazine.com/es/2015/10/how-to-build-a-low-tech-internet.html). |
|
|
|
|
|
|
|
****Sources & Notes:**** |
|
|
|
|
|
|
|
DIY: [Wireless networking in the developing |
|
|
|
world](http://wndw.net/book.html#readBook) (Third Edition) is a free |
|
|
|
book about designing, implementing and maintaining low-cost wireless |
|
|
|
networks. Available in English, French, and Spanish. |
|
|
|
|
|
|
|
\[1\] [Connecting the unwired world with balloons, satellites, lasers & |
|
|
|
drones](https://tech.slashdot.org/story/15/09/03/214256/connecting-the-unwired-world-with-balloons-satellites-lasers-drones), |
|
|
|
Slashdot, 2015 |
|
|
|
|
|
|
|
\[2\] [A QoS-aware dynamic bandwidth allocation scheme for multi-hop |
|
|
|
WiFi-based long distance |
|
|
|
networks](https://link.springer.com/article/10.1186%2Fs13638-015-0352-z#/page-1), |
|
|
|
Iftekhar Hussain et al., 2015 |
|
|
|
|
|
|
|
\[3\] [Long-distance, Low-Cost Wireless Data |
|
|
|
Transmission](http://www.ursi.org/files/RSBissues/RSB_339_2011_12.pdf) |
|
|
|
(PDF), Ermanno Pietrosemoli, 2011 |
|
|
|
|
|
|
|
\[4\] This link could only be established thanks to the height of the |
|
|
|
endpoints (4,200 and 1,500 km) and the flatness of the middle ground. |
|
|
|
The curvature of the Earth makes longer point-to-point WiFi-links |
|
|
|
difficult to achieve because line of sight between two points is |
|
|
|
required. |
|
|
|
|
|
|
|
\[5\] Radio waves occupy a volume around the optical line, which must be |
|
|
|
unemcumbered from obstacles. This volume is known as the Fresnel |
|
|
|
ellipsoid and its size grows with the distance between the two end |
|
|
|
points and with the wavelength of the signal, which is in turn inversely |
|
|
|
proportional to the frequency. Thus, it is required to leave extra |
|
|
|
\"elbow room\" for the Fresnel zone. \[9\] |
|
|
|
|
|
|
|
\[6\] [A Brief History of the Tegola |
|
|
|
Project](http://www.tegola.org.uk/tegola-history.html), Tegola Project, |
|
|
|
retrieved October 2015 |
|
|
|
|
|
|
|
\[7\] [WiLDNet: Design and Implementation of High Performance WiFi based |
|
|
|
Long Distance |
|
|
|
Networks](http://tier.cs.berkeley.edu/docs/wireless/wild_multihop.pdf) |
|
|
|
(PDF), Rabin Patra et al., 2007 |
|
|
|
|
|
|
|
\[8\] [Topology Patterns of a Community Network: |
|
|
|
Guifi.net](http://dsg.ac.upc.edu/sites/default/files/1569633605.pdf) |
|
|
|
(PDF), Davide Vega et al., 2012 |
|
|
|
|
|
|
|
\[9\] [Global Access to the Internet for All, internet |
|
|
|
draft](https://trac.tools.ietf.org/group/irtf/trac/wiki/gaia), Internet |
|
|
|
Engineering Task Force (IETF), 2015 |
|
|
|
|
|
|
|
\[10\] This is what happened to Afghanistan\'s JLINK network when |
|
|
|
[funding for the network\'s satellite link ran dry in |
|
|
|
2012](https://www.wired.com/2012/05/jlink/). |
|
|
|
|
|
|
|
\[11\] [The case for technology in developing |
|
|
|
regions](https://www.cs.cmu.edu/~mattkam/lab/publications/Computer2005.pdf) |
|
|
|
(PDF), Eric Brewer et al., 2005 |
|
|
|
|
|
|
|
\[12\] [Beyond Pilots: Keeping Rural Wireless Networks |
|
|
|
Alive](https://www.usenix.org/legacy/event/nsdi08/tech/full_papers/surana/surana.pdf) |
|
|
|
(PDF), Sonesh Surana et al., 2008 |
|
|
|
|
|
|
|
\[13\] <http://www.akshaya.kerala.gov.in/> |
|
|
|
|
|
|
|
\[14\] <http://main.airjaldi.com/> |
|
|
|
|
|
|
|
\[15\] [VillageCell: Cost Effective Cellular Connectivity in Rural |
|
|
|
Areas](http://www.cs.bham.ac.uk/~pejovicv/docs/Anand12ICTD.pdf) (PDF), |
|
|
|
Abhinav Anand et al., 2012 |
|
|
|
|
|
|
|
\[16\] [Deployment and Extensio of a Converged WiMAX/WiFi Network for |
|
|
|
Dwesa Community Area South |
|
|
|
Africa](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.452.7357&rep=rep1&type=pdf) |
|
|
|
(PDF), N. Ndlovu et al., 2009 |
|
|
|
|
|
|
|
\[17\] \"[A telemedicine network optimized for long distances in the |
|
|
|
Amazonian jungle of |
|
|
|
Peru](http://www.ehas.org/wp-content/uploads/2012/01/Extremecomm_sig_ISBN.pdf)\" |
|
|
|
(PDF), Carlos Rey-Moreno, ExtremeCom \'11, September 2011 |
|
|
|
|
|
|
|
\[18\] \"[Telemedicine networks of EHAS Foundation in Latin |
|
|
|
America](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4197650/)\", |
|
|
|
Ignacio Prieto-Egido et al., in \"Frontiers in Public Health\", October |
|
|
|
15, 2014. |
|
|
|
|
|
|
|
\[19\] \"[The design of a wireless solar-powered router for rural |
|
|
|
environments isolated from health |
|
|
|
facilities](https://eciencia.urjc.es/bitstream/handle/10115/2293/THE%20DESIGN%20OF%20A%20WIRELESS%20SOLAR-POWERED-2008.pdf?sequence=1)\" |
|
|
|
(PDF), Francisco Javier Simo Reigadas et al., in \"IEEE Wireless |
|
|
|
Communications\", June 2008. |
|
|
|
|
|
|
|
\[20\] [On a long wireless link for rural telemedicine in |
|
|
|
Malawi](http://users.ictp.it/~mzennaro/Malawi.pdf) (PDF), M. Zennaro et |
|
|
|
al., 2008 |
|
|
|
|
|
|
|
\[21\] [A Survey of Delay- and Disruption-Tolerant Networking |
|
|
|
Applications](http://www.jie-online.org/index.php/jie/article/view/91), |
|
|
|
Artemios G. Voyiatzis, 2012 |
|
|
|
|
|
|
|
\[22\] [Supporting Cloud Deployment in the Guifi Community |
|
|
|
Network](https://www.sics.se/~amir/files/download/papers/guifi.pdf) |
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(PDF), Roger Baig et al., 2013 |
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\[23\] [A Case for Research with and on Community |
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Networks](http://www.sigcomm.org/sites/default/files/ccr/papers/2013/July/2500098-2500108.pdf) |
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(PDF), Bart Braem et.al, 2013 |
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\[24\] There are smaller networks in Scotland |
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([Tegola](http://www.tegola.org.uk/)), Slovenia ([wlan |
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slovenija](https://wlan-si.net/)), Belgium ([Wireless |
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Antwerpen](http://www.wirelessantwerpen.be/)), and the Netherlands |
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([Wireless Leiden](https://www.wirelessleiden.nl/)), among others. |
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Australia has [Melbourne Wireless](http://melbourne.wireless.org.au/). |
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In Latin America, numerous examples exists, such as [Bogota |
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Mesh](https://www.facebook.com/BogotaMesh) (Colombia) and [Monte Video |
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Libre](http://picandocodigo.net/2008/montevideolibre-redes-libres-en-montevideo/) |
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(Uruguay). Some of these networks are interconnected. This is the case |
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for the Belgian and Dutch community networks, and for the Slovenian and |
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Austrian networks. \[8,22,23\] |
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\[25\] [Proxy performance analysis in a community wireless |
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network](http://upcommons.upc.edu/handle/2099.1/19710), Pablo Pitarch |
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Miguel, 2013 |
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\[26\] [RuralCafe: Web Search in the Rural Developing |
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World](http://www.ambuehler.ethz.ch/CDstore/www2009/proc/docs/p411.pdf) |
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(PDF), Jay Chen et al., 2009 |
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\[27\] [A Delay-Tolerant Network Architecture for Challenged |
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Networks](http://www.kevinfall.com/seipage/papers/p27-fall.pdf) (PDF), |
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Kevin Fall, 2003 |
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\[28\] [Delay- and Disruption-Tolerant Networks (DTNs) \-- A Tutorial |
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(version |
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2.0)](http://ipnsig.org/wp-content/uploads/2012/07/DTN_Tutorial_v2.04.pdf) |
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(PDF), Forrest Warthman, 2012 |
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\[29\] [Healthcare Supported by Data Mule Networks in Remote Communities |
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of the Amazon |
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Region](http://www.hindawi.com/journals/isrn/2014/730760/), Mauro |
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Margalho Coutinho et al., 2014 |
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\[30\] [First Mile Solutions\' Daknet Takes Rural Communities |
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Online](http://www.firstmilesolutions.com/documents/FMS_Case_Study.pdf) |
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(PDF), Carol Chyau and Jean-Francois Raymond, 2005 |
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\[31\] [DakNet: A Road to Universal Broadband |
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Connectivity](http://courses.media.mit.edu/2003fall/de/DakNet-Case.pdf) |
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(PDF), Amir Alexander Hasson et al., 2003 |
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\[32\] [DakNet: Architecture and Connectivity in Developing |
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Nations](http://ijpret.com/publishedarticle/2015/4/IJPRET%20-%20ECN%20115.pdf) |
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(PDF), Madhuri Bhole, 2015 |
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\[33\] [Delay Tolerant Networks and Their |
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Applications](http://www.citeulike.org/user/tnhh/article/13517347), |
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Longxiang Gao et al., 2015 |
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\[34\] [Low-cost communication for rural internet kiosks using |
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mechanical |
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backhaul](https://people.csail.mit.edu/matei/papers/2006/mobicom_kiosks.pdf), |
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A. Seth et al., 2006 |
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\[35\] [Searching the World Wide Web in Low-Connectivity |
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Communities](http://tek.sourceforge.net/papers/tek-www02.pdf) (PDF), |
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William Thies et al., 2002 |
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\[36\] [Slow Search: Information Retrieval without Time |
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Constraints](https://www.cs.cmu.edu/~yubink/hcir2013.pdf) (PDF), Jaime |
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Teevan, 2013 |
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\[37\] [Potential for Collaborative Caching and Prefetching in |
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Largely-Disconnected |
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Villages](http://mrmgroup.cs.princeton.edu/papers/isaacman-winsdr503.pdf) |
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(PDF), Sibren Isaacman et al., 2008 |
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-- |
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-- |
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Posted on October 26, 2015 at 12:26 AM in [Access to |
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information](https://www.lowtechmagazine.com/copyright_and_access_to_information/), |
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[Communications](https://www.lowtechmagazine.com/communications/), |
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[Cover story](https://www.lowtechmagazine.com/cover-story/), |
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[DIY](https://www.lowtechmagazine.com/diy/), |
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[Internet](https://www.lowtechmagazine.com/internet/), [Wireless |
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technology](https://www.lowtechmagazine.com/wireless_technology/) \| |
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[Permalink](https://www.lowtechmagazine.com/2015/10/how-to-build-a-low-tech-internet.html) |