Providing Free Wifi with Freifunk
A good friend wanted to have public wifi for a house where workers can get a room to stay while they are working for a company for a few weeks or months.
The problem with free Wi-Fi in Germany is the so called “Störerhaftung” (roughly translated to disrupter accountability). This means, that the person providing the internet access is responsible for the stuff which gets downloaded through their access point.
The current law situation is going in the right direction but currently one cannot just open a free wifi hotspot and still feel safe.
Freifunk Background
Freifunk is a German movement which solves this by providing a encrypted VPN solution which routes the traffic through one of their servers and takes the responsibility from you. As it is a free movement which does not include payment, they just don’t have any data of their users and therefor can’t give any information to suing companies from Sony.
This is a very cool project which is organized in many small associations which are working quite independently.
The nearest association is Freifunk-Aachen so I joined them (but currently not as a member, but I will do).
The federal state I live in is a quite active supporter of this movement and provides internet access at the citizens centers (Bürgerbüro) through Freifunk. A current situation change will happen as the Freifunk-Rheinland e.V. becomes charitable (gemeinnützig) which means, that you can get a tax refund from your donations.
What’s similar with all Freifunk associations is that they are using a fork of OpenWrt called gluon to simplify the installation of a router for it. As they have a lot of configuration differences between the associations, each is providing its individual freifunk firmware which must be flashed on a compatible router.
A map of all the Freifunk nodes in Germany can be found here
Cool, but what did you do?
Well, talking about the old O2 Box 6431 I had laying around which works with OpenWrt. I compiled the gluon firmware for my device (as it first will be supported with the next release) and had a lot to learn with it. Tested a lot but could not get it working from the beginning.
That’s why I finally bought a TP-Link Archer C7 Router which I had working with Freifunk in 5 Minutes.
I also had two Netgear EX3700 devices laying around. Netgear devices should never be used with the stock firmware as they started to require a user login since 1.0.5.4 (via blog.fefe.de) But thankfully they already are supported by OpenWrt and will be supported in the upcoming Gluon version (ref).
So I compiled the firmware for those devices and installed them which was working like charm.
The best part about this is that Freifunk is using a Mesh-Network via the Wi-Fi standard 802.11s which makes the network a lot more stable when switching the access points (AP).
Currently, the Freifunk Wi-Fi can’t use up the whole bandwidth as the VPN encryption needs too much CPU power and the small routers aren’t built for heavy VPN connections. This will get better this year after the switch from FastD as a VPN client to the newer WireGuard.
I learned a lot about networking from this project and got to know some very nice people who are quite committed to the Freifunk association.