What is Ronja?
Ronja (Reasonable Optical Near Joint Access) is an User Controlled Technology (like Free Software) project of optical point-to-point data link. The device has 1.4km range and has stable 10Mbps full duplex data rate. Ronja is an optoelectronic device you can mount on your house and connect your PC, home or office network with other networks. Or you can use it as a general purpose wireless link for building any other networking project.
The design is released under the GNU Free Documentation License: you get all the necessary documentation and construction guides free. The material costs are very low, about 100 USD. The operation is immune to interference and quite reliable - interrupted only by dense fog.