CW> and relaxation are in the same order of magnitude. Thus, a few microsecon ds of CW> storing the opposite data to the currently stored value will have

Excerpts from internet.cypherpunks: 4-Sep-95 Re: Emergency File Wipe Alg.. by MONTY HARDER@famend.com little e

ffect CW> on the oxide. Ideally, the oxide should be exposed to as much stress at t he

Here is a simple way to handle the problem, using our old discredited friend, XOR. Set up your software to periodically XOR the key with FFFF. This way, each bit will be a 0 half the time, and a 1 the other half. You have a flag that tells whether the key is in normal or inverted form, so that you can quickly perform any necessary computations on it, but there should not be any long-term memory effect.

On today's machines, it's a little more complicated than that. After you XOR the key, you have to then flush all the cache lines that contain the key, to make sure that the XOR operation makes it to the main memory. Unless I'm mistaken, a write-back cache will not propogate the XOR operation to main memory unless another memory operation(s) forces bumps the XORed key out of cache memory. Successive XOR operations on the key won't necessarily do this; you need some other memory op to flush the cache lines. _____________________________________________________________________________ Tim Nali \ "We are the music makers, and we are the dreamers of tn0s@andrew.cmu.edu \ the dreams" -Willy Wonka and the Chocolate Factory