geolocator (Software defined GPS)

Posted on by buttjantarek@googlemail.com
Hi everyone,
 
My name is Jan-Tarek Butt. I am in my fourth term of computer science at Emden University in Lower Saxony (Germany). Some of you may know me from the last Google Summer of Code. I am one of the students who is participating for Freifunk in the Google Summer of Code 2017. In the following post I would like to introduce you to my Google Summer of Code project. I split up the project, same like last year, into 3 main subjects: web backend, gps-share, LEDE Package,

web backend

The first one is a restful API backend[0], which should include a backwards compatibly to the api format of the old openwifi web backend[1]. The new backend should be written in Go, which will be clearer in the next few days. The New API should use Mozilla Location Service as fallback if it is not possible to determinate a position based on the own db entries. Received WiFi information can also redirect to Mozilla Location Service[2]. So some of you might have the question what is Mozilla Location Service. It is simply a service with a big database full of wardriving informations from mobilephones. Mobilephones scan for surrounded wifi networks and send this with its own position to the Mozilla Location Service. These datas will be integrated into the database. If you want to know your position without having GPS, just send only your surrunded wifis to the Mozilla Location Service and you will receive your position based on the wifi informations see the picture below.

gps-share

The first Idea was to create a software defined GPS as udev device which should provide NEMA-famata protocols over tty and receive the necessary informations over wifi. While discussing with people on the Mozilla Location Service Malinglist, it turns out that something similiar is already done in geoclue which provides geo coordiantes over dbus and can receive coordinates via Mozilla Location Service. geoclue works with network-NEMA and Mozilla Location Service. Over network-NEMA geoclue can receive GPS informations from Mobilephones and GPS modems working over local networks. To avoid of developing redundant software, i discussed with Zeeshan, the maintainer of geoclue, about building support in gps-share for standalone GPS instead [3]. This is a software which should provide GPS NEMA-Format from GPS hardware over network-NEMA for geoclue. gps-share is written in Rust for ensuring reliability.

geolocator

The third subproject is a new lede package called geolocator, which should provided geo positions received by their surrounded WIFIs. The WiFi informations should be sent to the new above mentioned backend[4].
cheers
Jan-Tarek Butt

GSOC 2017 – Implement NetJSON output in ubus (OpenWRT/LEDE)

Posted on by Arun

About Me:

I am Arunkumar Ravichandran, about to pursue my MS in Electrical and Computer Engineering at University of California, San Diego. I have almost 2 years of Software Engineering experience at EmbedUR Systems in the Wireless networks domain. I was working on wireless device drivers implementing Network assisted roaming and SDN support for the Linux based Enterprise Access Points and Wireless LAN Controllers.

What I am going to do in GSOC:

The main aim of the project is to bring in support for NETJSON object in the LEDE/OpenWRT Linux distributions. The support for NETJSON is brought in at the interconnect system – ubus. In this project, we need to add support for a new ubus API which allows retrieving these two NetJSON object types: DeviceConfiguration and DeviceMonitoring.

What is NetJSON ?

NetJSON is a data interchange format based on JSON designed to ease the development of software tools for computer networks. This specification defines several types of JSON objects and the manner in which they are combined to represent a network: configuration of devices, monitoring data, network topology and routing information.

Why NetJSON is important to OpenWRT/LEDE ?

Network infrastructure is deeply closed source. Open source won the battle in web development and system administration, but not in network management. The status-quo in networking is closed source software, poor interoperability and poor documentation.
NetJSON aim to challenge the status-quo and improve the openness of internet infrastructure by offering a set of tools (like a framework) which communities and companies can use to build network infrastructure using mainly open source software products.

– Federico Capoano, OpenWisp

  1. NetJSON would allow standardization similar to NETCONF. Since NetJSON uses JSON format, it makes the management of configurations done at a higher scale to be automated easily.
  2. By using NetJSON objects to either produce or collect information, in different vendor’s different hardware, it allows the developers to work on their ideas faster and in a better way.

Project goals:

  • Bring CLI support to accommodate the new parameters: DeviceConfiguration and DeviceMonitoring.
  • Write backend ubus APIs to collect the data and store the data in NetJSON objects: DeviceConfiguration and DeviceMonitoring and display them.
  • Revisit the implementation of JSON plugin in SCAL and try to extend the support for NetJSON. For the missing data models in the JSON plugin, try to write a data parser which uses the scal APIs to get data and convert that into NetJSON format and store in the DeviceConfiguration NetJSON object for outputting it.
  • Adapt the code in node-watcher agent and reuse it in SCAL as a plugin. This plugin should output the monitoring data in a NetJSON DeviceMonitoring format..
  • Writing makefile to compile the files added for supporting NetJSON in the ubus IPC/RPC system in OpenWRT/LEDE distribution.
  • Document the work done, installation guide and usage examples of the new CLIs.

Project Details:

  • CLI support: The CLI should be able to input the required data and display error message if entered wrongly. Generic CLI: ubus call netjson <config | monitor> <general | network | interface | none_to_display_all> <parameter | none_to_display_all> Example CLI: ubus call netjson monitor interface eth0 .The above CLI would display all the statistics related to eth0 in the DeviceMonitoring NetJSON format. CLI depth should be increased for certain commands like the interface and network entries to get the interface name. The cLI backend tool would be a separate API which calls the SCAL plugins.
  • ubus call netjson API support: We should register the namespace netjson in the libubus. This allows the procedures with any number of arguments.
  • NetJSON objects: SCAL is an abstraction layer to push information onto the ubus from the device.  SCAL allows gathering data on the device from UCI, ubus calls, shell commands, etc and publishes it on the ubus using a different datamodel. Already available SCAL JSON plugin takes these data models and convert it into a JSON format. My work involves extension of this plugin to support the NetJSON to be done. Add features to the JSON plugin in C which is needed in order to define the full data model using the NetJSON schema. Also for data formats which doesn’t have support in the SCAL JSON plugin, parse the scal datamodel and then store in a DeviceConfiguration NetJSON object. This is SCAL plugin is created for retrieving the information directly using C.

Timeline:

  • May 30th : GSOC coding officially begins.
  • Task to be completed by the 2nd June: Bring CLI support for the above things to be implemented. Test the CLI and check if error cases are handled by the CLI.
  •  5th June to 8th June: NetJSON DeviceMonitoring and DeviceConfiguration objects/schema structures to be defined in the ubus architecture. ubus call netjson API support is to be implemented in this time period.
  • June 12th till June 16th : Implement the NetJSON DeviceConfiguration to be retrieved for the whole device. The whole NetJSON DeviceConfiguration would be the output. SCAL plugin to be added to support the NetJSON format in C itself.
  • June 19th to 23rd : Making changes to the exisiting JSON plugin available in SCAL to transalate it into the NetJSON format.
  • June 26th : Demo to the OpenWRT/LEDE community apart from the mentors to get feedback. Based on the feedback improve the implementation.
  • June 26th to July 7th : Based on the inputs provided in the CLI, output the DeviceMonitoring NetJSON object. For eg: “ubus call netjson config interface wlan0 status
  • July 8th to July 20th : Implement the NetJSON DeviceMonitoring to be retrieved for the device in whole and display it.
  • July 20th : Demo to the OpenWRT/LEDE community apart from the mentors and get feedback.
  • July 21st to July 27th : Improve the implementation based on the feedback from the community.
  • July 28th : Phase 2 evaluation.
  • July 28th to August 10th : Based on the inputs provided in the CLI, output the NetJSON DeviceMonitoring object. For eg: This CLI would only output monitoring data for wlan0. “ubus call netjson monitor interface wlan0”
  • August 10th to August 21st : Improve upon any possible design based on the Mentor and community feedback.
  • August 21st to August 24th : Code cleanup, final documentation review and possible merge/commit to the LEDE/OpenWRT distribution or ubus.

GSoC 2017 Project – OpenWifi: LEDE/OpenWRT configuration Mangement

Posted on by Johannes Wegener

GSoC 2017 – OpenWifi

Hi, my name is Johannes Wegener and I’ll be working on OpenWifi this Google Summer of Code. I’m 27 years old and study computer engineering at TU Berlin. In this blog post I’m going to explain to you what OpenWifi is and what should be done during this summer of code.

What is OpenWifi?

OpenWifi is a OpenWRT/LEDE configuration management system. It is intended to manage a bigger or smaller amount of OpenWRT/LEDE devices.

If a new access point joins a network it is be able to auto detect the management Server and register to it. After the node has been registered its configuration (static configuration like what you’ll typically find in /etc/config/ on OpenWRT/LEDE devices) will be downloaded by the server and stored in a database.

It is now possible to query and modify aspects of the configuration. It also possible to change values depending on other values. This means configuration changes can be applied to a lot of different routers. There is an older templating system which shall be replaced by a new graph-oriented one. It also manages SSH-Keys, has a rudimentary file upload functionality (for uploading new images for example) and extensible API. It is possible for example for a node to ask for an image it should install. (Currently this is not very dynamic – but it is intended that an image could be selected on various parameters)

The Server also regularly pulls the health-state of the node and displays it in an overview. Furthermore the server acts as a luci2 proxy.

It is also extensible via PlugIns and is able to serve as an entry point to other services like icinga or location services. (Both already have a proof of concept PlugIn available)

How does it work? aka what makes it tick?

The main software is written in python and uses the pyramid framework and sqlalchemy as ORM. It uses pyramid-rpc for json-rpc requests (which is used for nodes to register for example) and cornice for a REST-style API (which is intended for the user of the system). The Core-System can be found in this repository.

Most of the tasks operating on nodes are done by a jobserver that uses celery – so that they don’t block the main thread.

All Webviews have been moved to a different repository and are realised in fact as a PlugIn. (If you just want to manage your nodes on CLI/with scripts this will be possible in the near future!)

The nodes use a notification script written as a shell script. It uses a fixed DNS entry (openwifi), a configuration file (/etc/config/openwifi) or mdns (using umdns or avahi) to detect a server and register to it. The packages can be found in the openwifi-feed repository. There is also a boot-flasher which is intended for flashing an alix2-style board from ramfs – since it is also possible to execute commands on the node I’ll integrate an update solution that uses sysupgrade.

The communication between the server and the node is realized currently via rpcd. But one goal during this Google Summer of Code is to abstract that and realize it via a rpcd-communication-PlugIn – this would make it possible to also a NetJSON-communication-PlugIn for example.

The PlugIns are realized with python entry points. There are some special named entry points which will extend the main application. You could have a look at the example plugin to get an idea how it works.

How to try it?

You can easily try the software with docker. Navigate to the Docker directory – there three files that will assist you with the setup. In conf.sh you setup if you want to use LDAP for authentication, avahi for mdns announcement and dnsmasq as dhcp server in the docker container.

With build_image.sh you build the docker image. It tries to detect if you need to use sudo for docker or not. Last but not least you need run_image.sh to start the image.

You can easily add PlugIns to the docker image if you just check them out or copy them inside the Plugins directory. To start off I would recommend to add the Web-Views Plugin and use avahi. Now you can navigate your browser to http://localhost:6543 to see the webviews (you need to restart the container after Plugin install – use docker stop OpenWifi and docker start OpenWifi).

What is needs to be done?

In the next section I’ll explain what should be done during Google Summer of Code. I need to prioritize these things because I’m not sure if it is possible to do everything. I think most important things are Testing, Authentication and the new graph-based database model.

Testing-Infrastructure

Currently just very few things have tests. But because it is possible to start a LEDE container in docker (there are some scripts helping to create a LEDE container in the Docker/LEDEImage directory) a lot of things are possible to test with docker orchestration. I want to provide a small LEDE image with the code to test it.

Before adding big new things I like to transfer the development to true test-driven development and having test for at least 90% of the core component code. And after that continuing development by writing tests first.

For that I would also have a look at coverage.py.

Security and authentication

There is a simplistic authorization for OpenWifi with a LDAP backend. I would like to add authorization based on user/password (without LDAP), API-Key and client side certificate (for the nodes to authenticate theirself against the API).

I would like to have the authorization as granular as possible. Authorization should check whether the authorized identity is able to operate on this node and what kind of action is allowed.

Security is provided by TLS. Last week I added the last bits to also use https for client communication – but right now it needs to be setup up by the user. I would like to add the appropriate hooks to the notification shell script.

Expand new graph-based DB-Model

The new DB-Configuration model is based on a graph – where configurations can be connected by links (the link can contain addition information – like what kind of link it is – currently the addition data is the option name (for example if you have a wifi-iface configuration the “device” links it to a wifi-device)).

The model is implemented and there is a query API to get and set options. But for communication purposes the configuration is stored as uci-json-config. There is code to convert between these two (but the one from uci to graph-model needs quite some more intelligence to detect everything right). There are also some hooks that update each part. But the update process is not consistent – the graph-based config gets a new ID for example. It would be nice to have a consistent conversion.

Furthermore I like nodes to share parts of a configuration. This should be easy to implement with some small DB changes. For this consistency is also very important. By default UCI generates unique strings for every configuration – this could be used for consistency.

The DB-Model also currently lacks creating new configurations and reordering configurations.

API

The API to modify nodes should get expanded and everything should get documented. (see above) This should be done in code and a document generated by sphinx.

I also like to implement a CLI program to use the API.

Versioning

The uci-json parser supports diffs between configurations. I would like to save a diff for each change which is applied – to have roll back configurations or delete a specific change.

There is a simplistic revisioning implemented. But the diff should be updated to a class of its own with json import and export and operations to apply a diff to a UCI configuration. (upgrade and downgrade)

Modularity and expandability

OpenWifi is right now is already quite modular – but I also want to modularize configuration parsing and communication. It would also be nice to have some interoperability with OpenWISP.

I use alembic for tracking database changes it would be nice to find a good way to use alembic for database changes needed by PlugIns as well.

Scheduled Updates

I want to schedule config updates – for example if you have a mesh you probably want to update the deepest nested nodes first and than the ones above etc. – this should be easy with celery (as long as the mesh is known and somehow represented in the database).

PowQuty Live Log introduction

Posted on by Stefan Venz

Hi everyone,

I’m Stefan and happy to present my GSoC 2017 project to you.
That is extending the PowQuty daemon and luci web-app with an event log and notification system for events violating the EN-50160 norm.
Probably most of you don’t know powquty. Therefore i will give a short introduction to it, before I present my actual project.
 

PowQuty

PowQuty[1] is an application for measuring power quality parameters of the power grid like voltage and frequency. It receives samples by a USB connected oscilloscope and writes the calculated values to a log file. This log can be read by the powquty luci web-app. The web interface will plot the measurements directly into several graphs. These are power over time, frequency over time and metrics over time.
It was implemented during the last GSoC by Neez El Sayed [2] and its intention is “to strengthen the role of open software in the uprising smart grids by providing some essential functionalities”.
 

PowQuty Live-log

The goal of this project is to provide an event log of measurements that are outside defined parameters.
Public power distribution networks have to meet certain criteria. These are formulated in the EN50160 norm.
If there is a power drop, or a frequency spike PowQuty will write this to its log like every other value. The user can examine the log file or its graphical representation for critical values, but essential equipment could already be damaged.
If such an event occurred, a user or power network administrator should be notified. This event log will get a graphical interpretation in the luci powquty app as well to enable a better tracking of events.
This will allow users of PowQuty to react quickly to changing conditions in power supply networks.

Therefore we will add a notification system to PowQuty as well as additional logging options.
To collect events at a central server we will extend the mqtt usage to send an mqtt notification on a violating event.
In addition we will add an email and slack notification option to allow quick responses.

 

[1]: https://github.com/thuehn/PowQuty
[2]: https://blog.freifunk.net/author/Neez-El-Sayed/

Our GSoC 2017 projects

Posted on by Andreas Bräu

In 2017 we got 15 slots for our projects. That’s great, we’ve never got so many slots for GSoC before. Our students are from 8 countries. They do their work for 6 sub organizations.

Until the end of May the Community Bonding Period takes place, so students can introduce their projects to the community. They also prepare together with their mentors the folling coding period.

This post will give a short overview on the selected projects. In the next weeks some detailed blog posts will follow describing all the projects.

GSoC project overview

Title Org Student Abstract
RetroShare Improvements retroshare ange The aim of this proposal is to improve RetroShare incrementally during the summer in the following work lines:
– Semi-automatic RetroShare friendship suggestion based on phone contacts
– Semi-automatize JSON API code and documentation generation
– Multiple simultaneous heterogeneous network connection for each peer
– Improve RetroShare Android usability and performances
– Seamless key exchange via Quiet Modem
– Chat and messages multiple device synchronization
– Directories multiple device synchronization
Implementing Pop-Routing in OSPF ninux Gabriele Gemmi Prince is a network daemon that continuosly monitors the network topology and sets the timers for OLSRv2, it is developed in C and we are currently deploying it in the Ninux community network in Florence. This year
we want to implement Pop-Routing for another link-state routing protocol: OSPF. OSPF is the state-of-the-art interior routing protocol for wired networks and it is used also in some wireless community networks. This
project consists in realizing a plug-in of the OSPF open source routing daemon (Quagga or Bird) that will:
– Expose the network topology to Prince using NetJson
– Receive and re-set the network parameters from Prince
Improving nodewatcher data representation capability wlan slovenija rasovica Currently nodewatcher has very limited overview of used IP space without more precise division of existing and used subnets. This could be improved using compact and colorful matrix with IP ranges and links to nodes. I would display data about used ips similar to the [IP Census 2014](http://census2012.sourceforge.net/images/hilbert_icmp_map_lowquality.jpg), better tables and other data representation that would help explain the network structure, it would help in explaining the network and its statistics even to an uninformed observer. I would also update the look and functionality of other graphs and tables representing statistical data from nodewatcher
Extending LoxiGen and ONOS to enable SDN control of wireless switches via OpenFlow lede Arne Kappen LoxiGen is a tool by the Floodlight project to generate OpenFlow libraries for several programming languages including Java and C. The goal of this project is to extend LoxiGen to include messages for controlling wireless switches using OpenFlow.
It will include the necessary extensions to LoxiGen as well as a proof-of-concept implementation of the control channel. This encompasses an application for the ONOS SDN controller and an agent for the LEDE router operating system.SDN-enabled wireless switches offer comfortable centralized management of larger deployments and may provide the basis for more complex use-cases in the future such as network slicing and seamless mobility.
OpenWRT/LEDE Configuration Management lede Johannes Wegener Improve the proof-of-conecpt version of a OpenWRT/LEDE configuration software.
Web interface for Retroshare, a secure communication software retroshare Stefan Cokovski I am applying to work on the web interface for RetroShare, secure communication software. RetroShare already has a web interface with limited functionality and questionable look, compared to the main Qt GUI which RetroShare uses. My goal will be to improve the already present functionalities, introduce new functionalities to the web interface and design a new look for the web interface.
Implement NetJSON output in ubus (OpenWRT/LEDE) lede Arunkumar Ravichandran To bring in support for NETJSON object in the LEDE/OpenWRT Linux distributions. The support for NETJSON is brought in at the interconnect system- ubus. To add support for a new ubus API which allows retrieving these two NetJSON object types: DeviceConfiguration and DeviceMonitoring.
DeviceConfiguration NetJSON object is filled in using the plugins available in System Configuration Abstraction Layer(SCAL).
DeviceMonitoring NetJSON is retrieved by reusing the code parts and adding hooks in the nodewatcher-agent.
LibreMesh Attended Sysupgrade libremesh paul0 Performing updates on routers is quite different from full Linux distribution. It’s not sustainable to do release upgrade via a packet manager. Instead it’s usually required to re-flash the system image. Depending on the installed packages an image rebuild may be to complex for regular users. A more convenient way is needed.

This project will implement an “image as a service” server side which provides custom build images depending on installed packages. A notification in the web interface will notify about the new release. After image creation a one-click installation is offered within the web interface.

The server side implementation will use established tools like LEDE’s ImageBuilder to provide an generic approach for image creating. In this way the entire OpenWrt/LEDE community including several community-mesh firmware projects will benefit from that new update routine.
Spectrum Analyzer libremesh Nicolas Andres Pace I believe that Community Networks’ Operating Systems could use the Spectrum Analysis a lot to make better decisions on how they use the electromagnetic field wisely and efficiently.

As of now, no Free OS has been using Spectrum Analysis, so they can’t know whether the radios are being used efficiently or not.

This module would allow all routers that use Atheros radios (the main radio manufaturer around) to see how is the spectrum and take better decisions on which channels they use.

Deliverables
* Create an OpenWRT/LEDE package to get Spectrum info from the radio.
* Create a LuCI interface to visualize the Spectrum information retrieved.
HMAC signing of Nodewatcher data & IPv6 support for Tunneldigger wlan slovenija red_moo Currently all monitoring reports by WLAN nodes are unsigned and can be spoofed by anyone. This represents a security problem and a possible solution is to add HMAC-based signing to encrypt node monitoring reports to prevent spoofing.
Nodewatcher’s monitoring system will also be improved so it will generate an event and a warning in case of a signature verification failure.The aim of the second part of this GSoC project is to design and implement IPv6 support for Tunneldigger so that it works in IPv6-only and IPv4/IPV6 mixed environment where both server and client have IPv6 connectivity in some form.
Add MPTCP support in LEDE/OpenWRT trunk lede SPYFF Create an MPTCP supported OpenWRT/LEDE trunk and ensure its operation in a multipath Wi-Fi aggregation environment. The trunk should contain the tooling for establish a SOCKS proxy for operating systems without MPTCP support.
geolocator (Software defined GPS) FF Nordwest Jan-Tarek Butt A dynamical and flexible geolocator which should provide a software defined GPS device and receives its position over WIFI hardware with various services like openwifi.su, MLS and etc.
netjsongraph.js: visualization of netjson data ninux GeekPlux NetJSON is a great work attracted some interest from around the world, but there are a lot of defects. And I’m a front-end developer and now focus on Data Visualization, so I want to contribute to NetJSON. In my proposal, I come up with my idea and list some tasks and schedules.
lime-webui: port to LuCI2 libremesh Marcos Gutierrez Make an inventory of all LuCI components that LibreMesh uses and that will not be compatible with LuCI2. Analyze which dependencies must be replaced or rewritten and generate the views according to the new framework selected.
Powquty Live-Log lede Stefan Venz PowQuty provides statistics from measurements taken by a USB oscilloscope. The statistics provide information about the power distribution network, but don’t highlight the most important information. Power networks need to comply with EN50160, if this norm is violated, damage to connected devices is possible.
To avoid damage, powqutyd will log violations and notify users on occurrence.

GSoC 2017 and Freifunk: Students wanted

Posted on by Andreas Bräu
GSoC Logo

Good news: Freifunk has been accepted again as mentoring organization for GSoC. If you’re a student, please bookmark March 20th in your calendar. That is the date when student application period opens and proposals can be submitted. In the meantime you should visit our ideas page and get in touch with the mentors and our community.

Applications for GSoC

This year we offer much more ideas than in the past but as always we don’t know how many slots (aka projects) we will get from google at the end. So we can’t give you any guarantee for proposals to be chosen. We will select the students and assign them to projects, but the final announcement will be made by the GSoC Program Office.

You aren’t limited to the ideas listed on our ideas page. It is possible to propose your own idea. But keep in mind that you need a mentor from one of our communities, too.

If want to apply please visit our students checklist page before. You can find a lot of information there on how to get in touch with our community. You’ll also find our application template there. It’s necessary to follow that template for a successful application.

During GSoC

There are some things we expect from you:

  • provide status updates to your mentor and your project, you should specify details with your mentor (how often, what medium to use, …)
  • commit early and often to the public repositories of your project
  • sign up our WLANWare mailinglist
  • join one of our community meetings
  • write at least 4 blog posts at this blog:
    1. During the community bonding period. Deadline is May 30 – introduce your project here, present your ideas, show us your project plan with milestone
    2. Before first evaluations. Deadline is June 26 – show your results and explain your status
    3. Before second evaluations. Deadline is July 24 – show your results and explain your status
    4. Before final evaluations. Deadline is August 21 – finally present your project and show us your result. Maybe it’s already live 🙂

To give you a short prospect of what is planned to get you into the project after successful application:

Timeline

Community Bonding (May)

Use this period to refine your proposal. Add more specific milestones. Try to get into software development, e.g. by fixing small bugs. Talk to your mentor and the developers of your project to introduce yourself and your proposal.

From 26th to the 28th of May (the last weekend before Coding Phase 1 starts) there’s the Wireless Community Weekend (WCW) in Berlin. Here the Freifunk community will meet with their guests to create an unconference and hackathon. You have the chance to learn a lot about free wireless networks. It’s your chance to show your project/idea to a lot of community members. So you can get your first feedback before coding starts.

If you need help with accomodation or travel costs, please don’t hesitate to ask your mentors or organization admins.

Coding phases

There’s something new this year: We have 3 coding phases with 3 evaluations. Both, students and mentors have to complete evaluations to proceed. Maybe you can use these evaluations as milestones of if you want to work agile as sprint dates.

If you can’t make it to the WCW in May there’s another great chance in the first coding period to meet a lot of developers and community members during Battlemesh V10 in Vienna from June 05 to June 10. Focus of this event are routing protocols. You can use that event to get a lot of detailed technical knowledge, e.g. by doing pair programming.

If you have any questions please contact the organization admins.

So let’s have a great summer! 🙂

(Thanks to Clemens who wrote some parts if this text before)

Runderneuerung blog.freifunk.net

Posted on by Andreas Bräu

Unser Freifunkblog ist auf eine neue Plattform umgezogen. Das alte Drupal 6, das sein Lebensende längst erreicht hat und keine Updates mehr bekam, haben wir abgelöst und die Inhalte nach WordPress migriert. Nun ist das Blog mit neuer Technik unter der Haube und neuem Design für die nächste Zeit gerüstet. Der älteste Artikel im Blog ist im Übrigen über 11 Jahre alt und stammt aus dem Jahr 2005.

Zugang zum Blog

Alle Artikel, Schlagwörter und Autoren sind erhalten geblieben. Frühere Benutzer wurden wieder angelegt, nur die Passwörter  haben wir nicht übernommen. Die Anmeldung kann mit der beim alten Blog verwendeten Emailadresse erfolgen. Mit der “Passwort vergessen”-Funktion kann man ein gültiges Passwort erhalten. Bei Problemen mit der Anmeldung schreibt bitte eine Email an das Webteam (web(at)freifunk.net).

Wer noch keinen Account auf diesem Blog hat und einen hier Freifunkartikel veröffentlichen möchte wendet sich bitte auch an das Webteam. Gerade für communityübergreifende Themen eignet sich diese Plattform.

Aufräumarbeiten

Einige Bilder lassen sich leider nicht mehr auffinden, da sie extern eingebunden waren und nicht mehr online sind. Auch der in Drupal integrierte Editor hat manchmal ganz schön viel unsinnigen HTML-Overhead erzeugt und führt auch unter WordPress zu komischen Formatierungen. Diese ließen sich nicht automatisiert aufräumen, das ist wohl mal ein Thema für einen Editathon :).

 

Implementing Pop-Routing – Final Evaluation

Posted on by Gabriele Gemmi

Hello again, for two months I have been working on my project and I have achieved all the goals.

An alpha version of my program was released for the mid-term evaluation.Since then I have fixed all the bugs, packaged the program for OpenWRT, tested the code and written the documentation.

Everything is available on the GitHub repository [0]

I structured my work opening by issues for all the bugs I had to fix and for everything I wanted to improve. Then, I organized the issues in milestones. Milestone 0.1 [1] is the one that I had to complete to finish the project. When that milestone was closed I made the branch “v0.1” [2].

Tests

In order to be sure that my program worked correctly. I wrote a simulator in python. It’s made by a small server, with the same interface as OONF’s telnet plugin, and two python libraries written by my mentor: cn_generator [3] and pop-routing[4]. The first one generates synthetic graphs using the Cerda-Alabern[5] algorithm, the second one is a pop-routing implementation in python. In the server I implemented the commands to push the NetJson[6] topology and the ones to receive the timers values.

When prince requests a topology from my test program, cn_generator generates a random graph and pushes it back; meanwhile using the python implementation of pop-routing, the references values are computed. The values received from prince are then compared to ones calculated using python.

The goal of tests is to verify that the difference between the reference and the measured values is always less than 1%.

Measurements

I’m going to use my work to write my Bachelor Thesis, so I wanted to perform some measurements to check how well it worked.

My goal was to implement the algorithm on an embedded device, so I chose to measure the execution time on a “Ubiquiti Picostation M2HP” to see how well it was performing.

I branched Prince [7], modifying the code to measure the time needed to calculate the betweenness centrality and push it back along with the timers.

I used the graph generator to create graphs from 5 to 500 nodes, and I measured the time needed to compute with a sample every 10 nodes. For each sample I ran 5 tests, then calculating the mean and the standard deviation. The results are shown here:

As you can see from the graphic above, the computation time on the embedded device is quite good if we use the heuristic (8s for 100 nodes), it proved to be unusable without it (100s for 100 nodes)

OpenWRT Package

The last objective I gave myself in the previous post was to write a plugin for OLSRd. Since OLSRd isn’t maintained anymore – and since all the developers are working on OONF – I decided to focus on it while avoiding the plugin. Instead, I wrote a makefile and packaged prince for openWRT / LEDE. The makefile hasn’t been published yet in any openWRT feed, but it is hosted in my repository [8]. Instructions are available along with documentation.

Future Work

I’ll keep working on this project, mantaining the code and fixing the future issues. Since the graph-parser library is the last piece of code implemented in C++ and it depends on the Boost libraries, I’m looking forward to re-implement it in pure C.

One of my goals was also to run prince in my WCN (Ninux Firenze), but switching from OLSRd to OONF is taking more time than expected, so I’m hoping to try it in the future.

Gabriel

[0]: https://github.com/gabri94/poprouting/
[1]: https://github.com/gabri94/poprouting/milestone/1?closed=1
[2]: https://github.com/gabri94/poprouting/tree/v0.1
[3]: https://ans.disi.unitn.it/redmine/projects/cn_generator/repository
[4]: https://ans.disi.unitn.it/redmine/projects/pop-routing/repository
[5]: https://pdfs.semanticscholar.org/4ac8/05e7359c6b20c3cdd5da24284d3826b9609c.pdf
[6]: http://netjson.org/
[7]: https://github.com/gabri94/poprouting/tree/exec_time
[8]: https://github.com/gabri94/poprouting/blob/master/Makefile.openwrt

Powquty (PoWer Quality) – GSoC 2016

Posted on by Neez El Sayed

Dear Freifunkers,

Now that GSoC 2016 comes to its end, please allow me to update you on the powquty project. Despite some delays regarding the hardware, the goals set for GSoC 2016 have been reached. Here follows a picture that shows a compact demonstration for powquty.

Small Powquty Demonstration

The picture depicts the set-up for powquty, which consits of a LEDE based wireless router, connected to the PC over serial interface, where a Termial session of the router is running. The oscilloscope is attached via USB to the router. On the router’s terminal session we see that powqutyd has been started, with the correspondent messages shown on stdout. These message show the calculated power parameters.

Installation

For installing powquty follow these steps:

  • add the following line to your feeds.conf in your source directory:

src-git powquty https://github.com/thuehn/powquty.git

  • update the your feeds, then install powqutyd from feed
  • Include powqutyd in your config (make menuconfig) by choosing powqutyd from: Utilities –> powqutyd
  • Save and exit menuconfig  
  • Compile and install powqutyd
  • scp the ipk file to your router and install it
  • opkg install powqutyd_0.1-1_<target>.ipk

Note this package depends on the following libraries/packages, that have to be installed before installing powqutyd:

  • libmosquitto
  • libconfig
  • kmod-usb-acm (kernel module)

When successfull the powqutyd package will create:

  • the binary powqutyd in /usr/sbin
  • the configuration file in /etc/powqutyd/powqutyd.cfg

Usage
Before running powqutyd you need to configure it.

  • Powqutyd needs to read the measurement samples from the USB oscilloscope. The USB oscilloscope has to be plugged to the router before running powqutyd. The USB oscilloscope implements the USB Communication Device Class (CDC) device specification. This means that the kernel module kmod-usb-acm will recognize the USB oscilliscope once plugged and will create a tty device probably under /dev/ttyACM0. Depending on your setup this could be different. Check your system logs after plugging the USB oscilloscope to find out the actual path of the tty-device on your setup and adjust the path in the config file of powqutyd (/etc/powqutyd/powqutyd.cfg) accordingly. Note: if the tty-device is not set right the powqutyd will not start!
  • Powqutyd will send the calculated power quality parameters using MQTT-protocol to an MQTT-broker. This means that powqutyd requires IP connectivity between your router and the MQTT-broker. Of course this is given if you set up an MQTT broker on your router itself, but this is not a requirement, as long as the router has an IP connectivity to an MQTT-broker. For testing purposes we used mosquitto on the router as MQTT-broker. Depending on your setup you need to adjust the mqtt_host config option in your /etc/powqutyd/powqutyd.cfg accordingly. The mqtt_host config option is a string that could contain either the IP-address of the Fully Qualified Domain Name (FQDN) of the MQTT-broker. Note: at the current state, the MQTT-client implemeted by powqutyd uses the port 1883 with no SSL support.
  • Furthermore the powqutyd’s MQTT-client is an publish only client, thus it will not subscribe and has no will. Nonetheless the topic under which the powqutyd’s MQTT-client publishes needs to be set. This can be done by adjusting the mqtt_topic config option in your /etc/powqutyd/powqutyd.cfg accordingly.
  • Powqutyd sends three types of messages to the MQTT-broker: i)msg_device_online, ii) msg_device_data, iii) msg_device_offline. These messages are explained below, yet all of them use a common setting which is a (universally) unique id for the devices that communicate with the same MQTT-Broker. This way the MQTT-broker can differenciate between the messages it receives. This device-unique-id is set by the config option dev_uuid
  • It is possible to print the results messages that powqutyd sends to the MQTT-Broker to stdout. This can be set by the option powqutyd_print. If set to 0 (zero) powqutyd will not print the result to stdout.
  • Running powqutyd: Once all the configuration above are done powqutyd can be started by typing: “powqutyd &” to your terminal.

Work achieved

For the powquty project, my mentor and I set up a dedicated Github page accessible under the following link:

https://github.com/thuehn/powquty

There the list of my commits can be seen under:

https://github.com/thuehn/powquty/commits/master?author=neez34

Code

The following picture depicts the folder structure of the work done during the porject.

.
├── etc
│ └── powqutyd
│ └── powqutyd.cfg
├── include
│ ├── calculation.h
│ ├── config.h
│ ├── emulator.h
│ ├── helper.h
│ ├── mqtt.h
│ └── retrieval.h
├── lib
│ ├── libpqlib.a
│ └── PQ_App.h
├── Makefile
├── src
│ ├── calculation.c
│ ├── config.c
│ ├── emulator.c
│ ├── helper.c
│ ├── main.c
│ ├── mqtt.c
│ └── retrieval.c
└── test
 ├── mqtt_test.c
 ├── usb_test.c
 └── vserial_test.c

During the project I had to reschedule the tasks planned repeatedly according to the progress and to the other circonstances. The order of the tasks changed significantly from the original plan, yet it was necessary to achieve the Goals of the project. Finally the tasks I did were in the following order:

  • First I had ported the library to a binary blob that can be used on the router.
  • Next I ve implemented the MQTT-functionality.
  • After that, I started working on the emulator, then I started working on the USB communication. For that I followed a trial and error approach, for which I used the folder called test to try out different things. Strictly speaking it is not needed at all for the software to compile and run, yet I kept it for future reference. For the USB comuication I implemented two solutions: One using libusb, and another one using virtual serial port (termios.h), since i wasn’t sure how will the USB oscilloscope will behave on the router and if any driver on the router will provide me with a tty device. luckily the kmod-usb-acm did so, thus i continued the project with the virtual serial port solution.
  • Once the USB communication was working, the next step was to retrieve the sampled data from the oscilloscope. First trials yielded the first sine signal as shown in the next figure

  • The picture shows ten sine waves corresponding to 200 ms, with 10kHz sampling rate, formed by 2048 samples. Yet as it can be seen the calibration was missing and the values were between +2500 and -2500. That is because the values (as seen in the background of the figure) where signed short numbers, and uncalibrated. (I used octave for plotting).
  • Once I was able to get the calibration parameters from the USB oscilloscope, I thereafter applyed them to the samples and got the expected sine – Wave with the Voltage-values expected in EU (RMS = 230 Volts) as shown in the next picture

  • After successful retrieval of the sampling values, I continued designing the software for powquty. I decided to use a multi-threaded approach with a Thread for sending MQTT-messages, a second for retrieving measurment samples and a third for calculating the power quality parameters. I included a ring-buffer as an interface between the retrieval thread and the calculating-thread.
  • once all three component were integrated and working together I added the configuration (using libconfig) instead of hard-coded MQTT-Broker address, and hard-coded TTY-device …etc.

Goals and future work

As described in the first blogpost, the goal of the powquty project within GSoC 2016 is to create a LEDE package which ensures the following three functionalities:

  • Retrieving sampled voltage data from the power quality measurement device via USB
  • Calculating statistical power quality parameters (such as: avg. voltage, harmonics, ect.) form the retrieved voltage samples
  • Provisioning of the calculated parameters for retrieval and graphical representation

At this point the powquty project has reached its first big Milestone where the basic functionalities set for the GSoC 2016, have been completely implemented.
Yet the end of one milestone is the begin of the next milestone.  This is why I conclude with some propositions for future work on powquty:

  • Design and implementation of error handling
  • Migration of the config to uci config
  • Design and implementation of another log option than stdout
  • Design and implementation of a Luci App for easy configuration and showing results

Nonetheless, please allow me to express my gratitude to my mentor, Dr. Thomas Hühn, for his outstanding support, and constant availability. Also great thanks are due to Freifunk, whose distinguished voluntary efforts – not only in regard to GSoC – made this possible in the first place. Last not least, great credits are due to Google for encouraging this innovative type of value creation.

Cheers,
Neez

DynaPoint Final

Posted on by Tobias Ilte

Hi everyone,

this is the final blog post about DynaPoint. Short recap: I created a daemon which regularily monitors the Internet connectivity and depending on that activates and deactivates the proper access points. That way the handling with APs would become easier as you already could tell the status by the AP’s SSID. I also created a LuCI component for it to make the configuration more easy.

In the past weeks I was able to add some new features, fix bugs and complete the LuCI component. Especially the latter was really interesting and gave me some knowledge about how LuCI works.

In the last post I mentioned that it’s better to verify Internet connectivity by using wget instead of just pinging an IP address.
Consequently I switched from Pingcheck to wget. I also added an option to use curl instead of wget. With curl you also get the option to choose the interface for the connection.
When you provide internet via VPN-interface you can explicitly check the connection of that interface now. The reason why I don’t use curl as default is because of curl’s rather large size. For some routers with only 4 MB of storage it might be too much.

I also added an “offline threshold”, which will delay the switch to offline mode. So for example when you set the interval to 60 seconds and offline_threshold to 5, the switch to offline mode will be made after 5 cycles of checking (=300 seconds).

So how does an example configuration look like?

To use dynapoint just add dynapoint_rule ‘internet’ and dynapoint_rule ‘!internet’ in the desired sections in /etc/config/wireless:

config wifi-iface
    option device ‘radio0’
    option network ‘lan2’
    option mode ‘ap’
    option encryption ‘none’
    option ssid ‘freifunk’
    option dynapoint_rule ‘internet’

config wifi-iface
    option device ‘radio0’
    option network ‘lan2’
    option mode ‘ap’
    option encryption ‘none’
    option ssid ‘freifunk-maintenance’
    option dynapoint_rule ‘!internet’

The configuration of dynapoint takes place in /etc/config/dynapoint:

config rule ‘internet’
    list hosts ‘http://www.example.com’
    list hosts ‘http://www.google.com’
    option interval ’60’
    option timeout ‘5’
    option offline_threshold ‘3’
    option add_hostname_to_ssid ‘0’
    option use_curl ‘1’
    option curl_interface ‘eth0’

All of that can also be configured via LuCI:

If you want to try out DynaPoint for yourself please visit https://github.com/thuehn/dynapoint for more information.

Future work

Currently there is only support for one AP per state. In the next weeks I want to add support for multiple APs per state.
Also I want to add support for more rules. At this time there is only support for one rule “internet”. I want to make this more generic and provide support for custom rules.

Acknowledgements

I want to thank my mentor Thomas Hühn for his excellent mentoring and great ideas during this project. 
Also of course thanks to Freifunk for letting me realize this project and thanks to Google for organizing GSoC.