I'm writing a blog entry about Tivoisation, how it works, what problems it causes, and how it can be blocked. I plan to put it on line on Monday, but any comments would be welcome. My main concern is whether it is easily understandable.
================== To think about what free software licences should do about tivoisation, we have to understand what problems we're trying to prevent, and how it works - so that we can find a way to make it not work. 1. How tivoisation works 2. Controlling your own computer 3. Sustaining the free software movement 4. What does discussion draft 2 of GPLv3 say 5. What do we have to think about ==How tivoisation works== Tivoisation is a way of giving someone a computer whose software can be upgraded but which will refuse to run any software that isn't first authorised by the manufacturer. To implement tivosiation, a manufacturer must do three things: 1. Put a chip in the computer which will check any software before it is run and which will only allow the running of software if an authorised digital fingerprint is found. 2. Inject that certain digital fingerprint into each version of their own software. 3. Don't tell their customers the fingerprint. By doing this, the manufacture can still publish new versions of the software in the future. It just has to inject the secret fingerprint and then publish the software and users will be able to run it. However, if the user tries to use a modified version of the software, or tries to run some third-party software, the computer will refuse to function fully, or will simply not run the software at all. ==Controlling your own computer== There are two reasons why free software licences should block tivoisation. The first is that tivoisation prevents users from having control of their own computer. We can see the importance of this by looking at the first company to do tivoisation: the Tivo. The Tivo is a tivoised computer which runs GNU+Linux. The software in the Tivo includes spyware which gathers information about the user and automatically sends that information to Tivo. The GPL ensures that Tivo owners can get a copy of the source code, but because of tivoisation, any effort to modify the software and use it will fail. Being able to get a copy of the source code is not enough in this case. ==Sustaining the free software movement== The second reason why free software licences should prohibit tivoisation is that tivoisation burns the environment in which free software flourishes. By making computers non-programmable, tivoisation makes free software users non-programmers. Normally, when our software spreads, we gain more developers as some of the users will know how to program, and they will make small or large changes, and many will publish their improvements so that everyone, including the non-programmers, can benefit from the general ability of the community to modify the software. With Tivoisation, the ability of the community to choose the direction the software develops in is inhibited, and the link between the spread of our software and the growth of our developer community is cut. If a million people bought Tivos, there would be an extra million GNU+Linux users in the World, and we would gain zero developers. This is unfortunate, to any degree, but it can also become particularly problematic if it becomes widespread. If we accept this behaviour from hardware manufacturers, we will get more of it because hardware manufacturers won't turn down the opportunity to have more power over their customers. If Tivoised computers become the norm and the era of programmable computers fades into history, free software development will be in trouble. ==What discussion draft 2 of GPLv3 says== Of the three components of tivoisation mentioned above, item #3 is the problematic one. If manufacturers implement #1 and #2, but told each customer the (possibly unique) digital fingerprint and how the customer can include it in software, then there would be no problem. Allowing items #1 and #2 is important because they can be used for security purposes. So, discussion draft 2 of GPLv3 blocks item #3 by saying that when you are required to distribute a program's source code, you must include: ...any encryption or authorization keys necessary to install and/or execute modified versions from source code in the recommended or principal context of use... This only applies to people distributing hardware plus software where the hardware is configured as in step #1 above. If you are just distributing software, then the number of keys that are necessary to install and/or execute the software is zero. So this language only applies to a small number of hardware manufacturers, probably less than ten. That sentence I've quoted is from the definitions of "Corresponding Source" in discussion draft 2 of GPLv3. Richard Stallman has said that in discussion draft ================== -- Ciarán O'Riordan __________________ \ http://fsfeurope.org/projects/gplv3 http://ciaran.compsoc.com/ _________ \ GPLv3 and other work supported by http://fsfe.org/fellows/ciaran/weblog \ Fellowship: http://www.fsfe.org _______________________________________________ Fsfe-uk mailing list [email protected] http://lists.gnu.org/mailman/listinfo/fsfe-uk
