Freifunk

Freifunk (German for: "free radio") is a non-commercial open grassroots initiative to support free computer networks in the German region. Freifunk is part of the international movement for a wireless community network. The initiative counts about 150 local communities with over 25,000 access points. Among them, Munich, Paderborn, Aachen and Hamburg are the biggest communities, with more than 1000 access points each.

The main goals of Freifunk are to build a network that is decentralized, owned by those who run it and to support local communication. The initiative is based on the Picopeering Agreement. In this agreement, participants agree upon a network that is free from discrimination, in the sense of net neutrality. Similar grassroots initiatives in Austria and in Switzerland are FunkFeuer and Openwireless.

Like many other free community-driven networks, Freifunk uses mesh technology to bring up ad hoc WLAN networks. In a mesh network, all routers connect to each other using a special software. When a router fails, this software automatically calculates a new route to the destination. In this case, the software is called Freifunk firmware and it is based on OpenWrt and other free software. There are several different implementations of the firmware depending on the hardware and protocols local communities use. The two common protocols are and B.A.T.M.A.N. The development of B.A.T.M.A.N. is driven by Freifunk activists.

One of the results of the BerLon workshop in October 2002 on free wireless community networks in Berlin and London was the Picopeering Agreement. This agreement about rationales of free networks describes how the transmission of other people's data is handled in a free network and has become a core agreement of the community. During the workshop, participants also agreed upon regular meetings in Berlin to build their own free wifi network. Ever since, there have been weekly meetings at c-base Hackerspace every Wednesday. At the same time, the German language site freifunk.net was started.

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Wikipedia