eraseruser0 said:
Well just saying, his original comment was that each tool leaves its own trail. Eraser does not attempt to hide its own trail. Whether that's a big deal is beyond me. I'm not particularly worried about that point, he was.
I think that there are two things going on here.
The first is the distinction between random and pseudorandom. 'Random' implies that there is no pattern or logic that connects a member of a set to any of the other members of the set. As computers work by executing sets of instructions, and each set of instructions contains logic, computers cannot generate random data; if you know how the data is generated, the data is not random; this, I think, is Joel's point. 'Pseudorandom' implies that, while there is a connection between the members of the set, it is difficult or impossible to discern this connection from the data in the set alone; in this sense, Eraser generates pseudorandom file and folder names. This makes it difficult to know (and certainly to prove) what the original file names were; this is even more the case with a free space wipe, as the data Eraser writes bears no relation with the data that is overwritten.
The second point is that, as file and folder names are typically anything but random, the very fact that Eraser's names are pseudorandom makes them distinctive. If, for example, you use a file recovery utility to test a free space wipe, it is pretty easy to see which are Eraser's 'rubbish' files, used for overwriting and which are not. The only information that gives someone else is that Eraser (or a similar program, if there is one) has been used on the drive; in most circumstances, that will not compromise user privacy and security. In circumstances where the fact that Eraser has been used is an issue, the only truly secure course of action is to physically destroy the drive after wiping it and then put the pieces somewhere where they will not be found.
David