48 7. BUILDING FOR FREEDOM: OPEN DATA, OPEN SOURCE
server, they will be peer-to-peer applications, seeking out other users and interacting with them directly.
Some great strides have been made in building peer-to-peer software, in no small part because of the vast amount of interest in using the technology to share music without getting caught by enforcers of the law. But, especially compared to Web 2.0 server technology, peer-to-peer is still in its infancy. Writing a social application so that its peer-to-peer is about a thousand times harder than writing the same program as a web app.
Still, peer-to-peer software, if we could make it work, would seem to give the best of both worlds: the freedom to modify how a program functions on our local computers as well as the ability to share and collaborate with others across the Internet. And so, for those who care about freedom (as well as those who care about sharing music), this seems like an important avenue for further research.
In the meantime, even if, like the question of how to query across many large SPARQL databases, the problems of web application freedom are unsolved, you can still do get started. The Open Knowledge Foundation, a group promoting freely shared databases, has proposed an Open Software Service Definition.[1] The definition essentially codifies the principles we discussed above:
1. Make your code available as free or open source software
2. Make your data available as Open Knowledge
For free/open source software, there’s the official lists of the Open Source Initiative and Free Software Foundation to tell whether your license is sufficiently free and open. Examples include the Expat/BSD license, the GPL, etc. The Open Knowledge Foundation similarly lists a series of licenses including some Creative Commons licenses, the GNU Free Documentation License, and so on.
That’s the legal details, but the technical ones are just as simple: provide a source code repository for all your code and SQL dumps for all your data.
Of course, this leaves a lot of open questions. What about private data, for example? My own feeling is that people should at least be allowed to download their own data and any data they can access through the Web interface—e.g. the data about your friends on Facebook.
