Legal P2P, part 2

Let's go over some of the details of the system described in part 1.

You might wonder, what would happen if the person that has the file "checked-out" refuses to return it. My proposal would be that the system would essentially render the file useless. I mean, what happens if you lend a cd to a friend and that friend loses it? The cd is gone (but not your friendship - hopefully).
Now, nothing would prevent you from reimporting the file into the system, but the point would be to make it painful enough to discourage you to use the system to share data with others, yet that would allow you to recover from these cases. I will make the analogy that it's like you backing up a cd and lending a copy to a friend. If he loses or destroys the copy you can always use your backup to make a new copy, but obviously that is a painful thing to do.
The second method would be to use DRM to prevent the file from working past a certain date. This way the application could essentially assume that the file would be usable past a certain point.
I prefer the first method because it doesn't require a centralised DRM. To be effective, the second system requires a central server that verifies if requests are valid or not.

Next time I will talk about the file system I would use to store all this.