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<br><div><br>Hello Community,<br><div dir="ltr"><br>I am from Freifunk Berlin and would like to introduce to you an implementation of a node database I started with a friend we call yaffmap. <br>It got its name because at that time we have had many mapservers in Berlin and so it started as yet another approach for a Freifunk map.<br><br>The intention was to make a server that not just produces points and lines (nodes and their links) but to gather all information that might <br>help to understand why a link is as bad as it is. This includes to gather wireless scan results, the effective rate chosen/calculated by the <br>wireless driver to a specific neighbour and so on. Furthermore it had to be independent from the routing-protocol and its daemons (but <br>needs it to gather useful info) and the IP version (or even no IP version for RPs like batman) and had to be able to upload and store data <br>from multiple routing protocols on the same node. In order to sample so much information we went the route of scripting an agent for the <br>map-server which runs on the nodes gathering the information and uploading it through a JSON interface to the server. For link-state-protocols <br>like OLSR we even implemented the upload of the global topology to the server, which gave us some headache. From the beginning on <br>I stressed the need for decentralized operation, so replication between the servers was implemented and any community which wants can <br>have their own map data server. Moreover I cleary wanted the datacollection/storage to be independent from the frontend the map user is <br>presented. In Berlin everytime a new map came along and an old one was gone we saw huge ammounts of data simply disappear. So the <br>server only provides a SOAP interface for UIs and other services to use to get map data. The representation of a node in the database ist <br>best seen on a graphic. I uploaded it to imageshack, see [1]. A little bit of documentation is found under [2], but wasn't thoroughly updated <br>after we left concept stage.<br><br>We got to the point where the agent (bunch of shell/AWK) for the nodes runs on openWRT (best with madwifi and ath9k/ath5k) with olsrd <br>(other routing daemons simply need scripts for data gathering, agent is held modular), uploades many useful information to the server (or <br>another if the first does not respond; multiple can be configured) using JSON, where it gets stored correctly into a SQL database and replicated <br>to other servers and provided through a SOAP interface. The agent even is already provided as a package in the respected PBerg Freifunk <br>Firmware. There also exists a 'proof-of-concept' implementation for a map frontend, see [3]. The code is hosted on github as seen und [4]. <br>Because of the frontend development got stuck the frontend SOAP interface is not very sophisticated nor much tested as is the frontend itself.<br><br>The result is a database which can answer more complex question to the mesh engineer or software developer than every I took a look at. <br>Maybe you want to know the average effective rate on all 11n interfaces or all 5GHz interfaces? Or you might be interested in the average <br>ETX on different channels in a certain geographic area. Or you want to compare how different routing daemons evaluate the quality of a <br>certain link. Maybe you even want to draw a noise map. Or wouldn't it be interesting to see the correlation between the effective rate of a <br>wifi link and the metrics which result in the routing daemons?<br><br>Because the node data includes a 'misc' field through which any kind of node id or statistics could be stored/sent this is can even be integrated <br>into existing community portals.<br><br>Hope you find this interesting<br>Dennis<br><br>[1] http://imageshack.us/f/21/bildschirmfotovom201204.png/<br>[2] http://wurststulle.dyndns.org/yaffmap/trac/wiki/DocumentationIndex (Be patient. It is dripping through an ADSL upload)<br>[3] http://yaffmap.basicinside.de/vendor/yaffmap-map/<br>[4] https://github.com/wurststulle/yaffmap-backend <br> https://github.com/wurststulle/yaffmap-agent <br> https://github.com/wurststulle/yaffmap-map<br>[5] some statistics: http://wurststulle.dyndns.org/yaffmap/<br> </div></div> </div></body>
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