[rtpg]

Sorry, I might not have been clear.

I don't know if its being stored, I agree that it shouldn't be.

But so many people in this thread seem to imply it is impossible to filter a stream of information without storing the entire stream. This is very disingenuous, and is about as true as saying that it's impossible to have cops camping out for a guy with a specific license plate because they'll have to look at every car, and so they'll have to memorise all of them.

This obviously depends on the selectors, but we're talking about online filtering here, guys. Its possible to imagine a situation where not every single piece of data is stored.

[couchand]

Well, at the very least the data resides in memory and the CPU cache. We could discuss whether that constitutes "storage" but I do think it's significantly different than the personal memory of a police officer. A more appropriate analogy might be a traffic camera looking for the specific license plate.

EDIT: Note that the purported benefits of these collections programs (according to many of the slides) is that the selectors can be determined after the fact. So they must be keeping data somewhere.

[talmand]

Well, I see it as a more potential problem if the cops don't know the license plate number they need up front so they record every single one they see. Then this data is stored until someone can go looking through them to find the plate they actually need. The question is what happens to the complete list at this point?

Which, interestingly enough, the process of recording and storing license plate numbers for various uses is already in play. Both by private and public agencies.