Mesh Networks

Free Community Networks in Catalonia with

Ramon Roca from talking to ARTE-TV.

Thanks to Elektra for the translation.

Gurb in Spain
1002 km to Brussels

Ramon: The NSA scandal almost makes us laugh I have founded so we can build broadband internet access ourselves.

Voiceover: Here in the middle of the catalan nowhere a digital revolution started 10 years ago.

Ramon and his neighbors have build their own broadband internet because the big commercial providers had no interest in providing access to the village and its vicinity. Today, is one of the greatest altenative networks in the world.

Ramon: I want to show you where the cables merge together. Right here. This rack is the equivalent of a telephone switchboard in a village. It is a bit dirty because this shag actually belongs to my garden. What it can do is impressing. I can't say it precisely, but these are the routers of 5000 households.

Overdub: In a Freifunk-Network the participants are networking among each other and not via Internet providers. They can directly share data with each other, chat, write e-mails. A decentralized network that the users control themselves.
Thereby their data is secured from access by third parties. Meanwhile, the Internet-Guerilla are able to roll out their own fiberline network. Today, Ramons colleagues are working since 3 AM. We all know that the government operates slowly.
We can't wait until laws are solving all our problems.

In our case this also comfortable for us: With regards to communication, we can do or not do whatever we like.

Freifunk Google Summer of Code 2014

We are excited that Freifunk has been accepted as a Google Summer of Code Mentor organization again in 2014.

We are now looking for interesting student projects. Participating community networks and projects have already put up a list of ideas on the wiki.

Students can apply for example for projects developing packages for OpenWrt (the basis of the freifunk firmware) extending its functionality or other useful network tools such as management server tools, graphic interfaces for existing tools, map extensions, p2p tools that take routing into consideration, implementing wlan sleeping modes, routing protocols and more.

The deadline for student applications is 21 March: 19:00 UTC. We recommend to start your application now. You also need to add an enrolement form into the system.


Freifunk Google Summer of Code Timeline

21 March:

19:00 UTC

Student application deadline.

Interim Period:

Mentoring organizations review and rank student proposals; where necessary, mentoring organizations may request further proposal detail from the student applicant.

7 April:

Mentoring organizations should have requested slots via their profile in Melange by this point.

9 April:

Slot allocations published to mentoring organizations

Interim Period:

Slot allocation trades happen amongst organizations. Mentoring organizations review and rank student proposals; where necessary, mentoring organizations may request further proposal detail from the student applicant.

15 April:

First round of de-duplication checks happens; organizations work together to try to resolve as many duplicates as possible.

18 April:

  1. All mentors must be signed up and all student proposals matched with a mentor - 07:00 UTC

  2. Student acceptance choice deadline.

  3. IRC meeting to resolve any outstanding duplicate accepted students - 19:00 UTC #gsoc (organizations must send a delegate to represent them in this meeting regardless of if they are in a duplicate situation before the meeting.)

21 April:

19:00 UTC

Accepted student proposals announced on the Google Summer of Code 2014 site.

Community Bonding Period:

Students get to know mentors, read documentation, get up to speed to begin working on their projects.

19 May:

  1. Students begin coding for their Google Summer of Code projects;

  2. Google begins issuing initial student payments provided tax forms are on file and students are in good standing with their communities.

Work Period:

Mentors give students a helping hand and guidance on their projects.

23 June:

19:00 UTC

Mentors and students can begin submitting mid-term evaluations.

27 June:

19:00 UTC

  1. Mid-term evaluations deadline;

  2. Google begins issuing mid-term student payments provided passing student survey is on file.

Work Period:

Mentors give students a helping hand and guidance on their projects.

11 August:

Suggested 'pencils down' date. Take a week to scrub code, write tests, improve documentation, etc.

18 August:

19:00 UTC

Firm 'pencils down' date. Mentors, students and organization administrators can begin submitting final evaluations to Google.

22 August:

19:00 UTC

  1. Final evaluation deadline

  2. Google begins issuing student and mentoring organization payments provided forms and evaluations are on file.

22 August: 20:00 UTC

Students can begin submitting required code samples to Google

25 August:

Final results of Google Summer of Code 2014 announced


* GSoC Page:

* Idea Page:

Freifunk Summer of Code ten students accepted

Thank you to all applicants for the Freifunk Summer of Code project and congratulations to the accepted students! All together there were 49 applications for Freifunk. We could accept 10 students. They are currently updating their project proposals. I will present them here soon. We invite the students and anyone else to our Wireless Community Weekend at the end of May. More info coming out soon. Good luck for your summer of code projects For everyone who did not get in or people who did not apply, we welcome every contributor and user of the freifunk software tools and are looking forward to your involvement outside the Summer of Code.

OpenWrt team announces OpenWrt Kamikaze 808 Release with Luci Interface

The OpenWrt team (Cph) has announced a new version of its Linux distribution for embedded wireless devices named "OpenWrt Kamikaze 808 Release". I talked to Felix Fietkau already at the WCW. Unfortunately we did not have the time to do an interview at the end. But Cyrus from freifunk Halle gave a short showcase of his interface (in German). The OpenWrt team was also impressed by it and they now announce the enclosure of the Luci interface officially. Congratulations Cyrus!

It has been quite a while since OpenWrt had a new Kamikaze release. The developer team has decided that it is time to get things straight and focus on a new release. This release have the official name: OpenWrt Kamikaze 808 Release.

The schedule will look like this:
*Last day in July - final release candidate: 808 RC-1 808 RC-1 will be a feature freeze, and all changes after this point will be bug fixes.
*Last day in August - final release: OpenWrt Kamikaze 808 Release.

OpenWrt Kamikaze 808 Release will focus on bringing the following:
- Firewall rewrite
- Broadcom 47xx running reliably with the new Kernel, not including wifi
- IMQ and Traffic shaping tested with newer kernels, especially 2.6.25
- Sysupgrade for more platforms (x86 is tested again)
- The new web interface (LuCI, Lua Configuration Interface)
- Attention towards the integration of security updates
- Package maintaining and updates between releases
- Testing, testing and lots of testing...

The 808 Release will also include support for several new platforms/targets. ( )

Training Materials for Wireless Networks from WiLAC available for download

WILAC, an initiative to promote wireless technolgies in Latin America and the Caribbean ("Tecnologías inalámbricas para el Desarrollo en América Latina y el Caribe"), has published some of their training materials in English. I uploaded their presentations to Slideshare for people to be able to embed them into their websites and blogs. Here is the presentation with an introduction to Wimax.

As part of the TRICALCAR project a set of 7 brand new modules, which we are please to share with the group of technicians part who develop the original curriculum of the CWCA project in Africa. We know publish this materials in English, as a feedback to the community who has been using the original curriculum. The materials are publiched under the same formats and conditions of the rest of the TRICALCAR project. (16 Junio, 2008 - 11:00 AM,

The materials were created by different wireless experts including Ermanno Pietrosemoli (well-known for his longrange wireless connections), Alberto Escudero-Pascual, Louise Berthils, Lilian Chamorro, Dafne Sabanes Plou and Alberto Escudero Pascual.

The WILAC website is part of an initiative of ESLARED with the support of the Instituto para la Conectividad en las Américas (ICA). More presentations and Handouts can be downloaded or viewed at my Slideshare account. The Spanish versions of the workshops are also available at their site.

To learn more about Wimax, check out Wikipedia:

WiMAX, the Worldwide Interoperability for Microwave Access, is a telecommunications technology that provides wireless data in a variety of ways, from point-to-point links to full mobile cellular type access. It is based on the IEEE 802.16 standard, which is also called WirelessMAN. The name "WiMAX" was created by the WiMAX Forum, which was formed in June 2001 to promote conformance and interoperability of the standard. The forum describes WiMAX as "a standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL" (and also to High Speed Packet Access).(Version 17 June 2008, at 10:39,

Open Hardware from Squidbee for Wireless Sensor Networks

A couple of weeks ago I was talking with Alex about meshlium. I found out more about the project now. Last week I did an interview with Jose Luis Marina from Peopleware at a workshop of FOSS Bridge in Hanoi. Peopleware develops Osmius a very advanced monitoring tool to monitor all kinds of devices. He told me about their idea of using the open Squidbee hardware for their sensor networks. They want to be able to transfer data from sensor networks in an easy and affordable way. A scenario I see here is to use mesh networks for the transmission.

SquidBee is a project that uses an open hardware design as well as open-source software as a platform for remote control and sensing: "SquidBee is an Open Hardware and Source wireless sensor device. The goal of SquidBee is getting an "open mote" to create Sensor Networks." SquidBee uses the ZigBee self-organizing low power wireless mesh network protocol. ZigBee operates in the unlicensed 2.4 GHz, 915 MHz and 868 MHz ISM bands with data rates from 20-250 kbit/second, per channel. ZigBee is optimized for super low power operation so that the devices can be operated from battery power for long amounts of time. For long-running outdoor applications, powering the devices from photovoltaic panels would be an obvious technology choice. Using the 1mW XBee power level, the XBee maximum device-to-device range is 100 meters. At the 100mW XBee pro power level, the range is extended to 1KM. Each additional node can extend the range of the mesh network, since data passes through the nodes. (Download, June 16, 2008,

Behind the project is Libelium Comunicaciones Distribuidas, a SpinOff company of the University of Zaragoza (Spain) which has develop the ZigBee communication module. The Libelium team is formed by Marcos Yarza, Alicia Asín and David Gascón. The board has been developed by the Arduino team by David Cuartielles, Massimo Banzi, David A.Mellis and Tom Igoe. They come from different institutions in Spain, Sweden, Italy and New York (compare:


Some more info from the Squidbee wiki:

The main concepts behind SquidBee are:
* Self-powered
* Wireless Comunications
Repeat with me: "Ubiquity, Ubiquity, Ubiquity..."

How does SquidBee work?  

  1. Acquires  values from environment parameters: temperature, humidity, lightness, presence, pressure or (almost!) whatever you can sense.
  2. Operates with these values, when required.
  3. Transmits these values using a low power comsumption wireless technology (ZigBee).
  4. Sleeps until next timeout and repeats from the first stept.

Second step is not always necessary, depending of the calculations needed it may be better to make them in receiver computer to save nodes energy.

An open mote? What does it really mean? It means every part of the mote is accessible and can be studied, changed, personalized, ... From the schematic circuit to the source code of the programs that are running inside the mote.

Who is interested in SquidBee? Anybody who is researching in the environment monitoring field. This is also an educational project so that universities can offer to the students a multi-learning device. With SquidBee people can learn at the same time electronic, programation, communications... and everything in just one device.

Who is supporting SquiBee? The board inside SquidBee has been developed by the Arduino team. The communications module wich lets  the node transmit through a ZigBee module has been developed by Libelium. Both components are open hardware and they have a really strong community support. A specialized wiki related to SquidBee and the Sensor Networks  will be created soon. There, all the Arduino and Libelium tutorials and examples will be shared and other research teams will be able to exchange their knowledge with the community.

What can I do with SquidBee? The main concept is: "sense what you want where you want and transmit it".

Two configurations of SquidBee? What is it exactly? Using the same board and communications module we have created 2 kinds of SquidBee: the sensor mote and the gateway. The first one is the self-powered sensor mote and the second is the computer USB connected receiver.

Can I integrate SquidBee into a wireless 802.11 Mesh network? Yes! We have also developed an outdoor Mesh Router: MeshLium which you can use to collect the information using the ZigBee protocol and transmit it to the mesh network using the Wifi technology (802.11). (Version, May 15, 2008, 15.22,

Wireless Kernel Tweaking or how B.A.T.M.A.N. learned to fly - Presentation at the 24c3 by Marek Lindner and Simon Wunderlich

Marek Lindner and Simon Wunderlich from the Berlin freifunk community gave a talk on Wireless Kernel Tweaking and the B.A.T.M.A.N. routing protocol at the 24c3 Chaos Communication Congress. The video is now available on the torrent network.

Kernel hacking definitely is the queen of coding but in order to bring mesh routing that one vital step further we had to conquer this, for us, unchartered territory. Working in the kernel itself is a tough and difficult task to manage, but the results and effectivity to be gained justify the long and hard road to success. We took on the mission to go down that road and the result is B.A.T.M.A.N. advanced which is a kernel land implementation of the B.A.T.M.A.N. mesh routing protocol specifically designed to manage Wireless MANs.

During the last years the number of deployed mesh networks has increased dramatically and their constant growth drove us around the edge of what we thought was possible. To cope with this rapid development we had to leave the slow and limited track of tweaking existing approaches and take an evolutionary step forward by porting the B.A.T.M.A.N. protocol into the kernel land and going down to layer 2. Using B.A.T.M.A.N. advanced as a showcase we will, in our lecture, deliver a detailed review on how one can go about developing linux kernel modules, give insights in what difficulties to expect and provide practical tips on how to go about this challenge without experiencing a damaging kernel freeze in due process.

We will describe what problems we faced migrating down to layer 2 and how we went about solving them for example how we moved away from the kernel routing and handle the actual routing and data transport in B.A.T.M.A.N. itself. Also moving to layer 2 meant to leave IPs behind and solely rely on MAC-routing enabling features like DHCP, IPX, IPv6, etc which up to now was not possible and therefore comes as a big plus. On the other hand there were little if none diagnostic tools at all for routing on that level so we had to go back one step and develop the tools we needed ourselves.

These and other things we will cover in our presentation and also give an outlook into the future of mesh-routing, which will bring it even closer to the source of wifi - the wireless stack and its drivers and thereby improving the overall performance even more.



WiOpt'08 - International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks

(vie Thomas Hirsch)
Vielleicht interessant für den ein oder anderen, der der Wissenschaftswelt einmal über seine Erfahrungen und Ergebnisse im Freifunk-Netz berichten möchte.
Was bringts:
- Feedback. Das Papier wird auf jeden Fall von drei Leuten aus verschiedenen Fachgebieten quergelesen. Anschließend darf man einen Vortrag vor noch mehr Leuten halten, und wird im Konferenzjournal abgedruckt. Potentiell erreicht man also viele Leute, die Ahnung von Mesh-Dingen haben, Interessante Dinge  mit Funknetzen machen, oder sich das ganze auch mal nur aus der Mathematikerbrille betrachten.
- Aufmerksamkeit über den eigenen Kiez hinaus.
Übersicht über die Beiträge und Teilnehmer hier:

6th Intl. Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks March 31 - April 4, Berlin, Germany

Scope of the Symposium
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