I'm not so sure I see the great usefulness of this attack. I've taken a cursory glance at Mr. Kocher's paper on-line and what it comes down to essentially, if I undestand it correctly, is that you need to be as sure of the timing as you can be. Now, on a distributed system, you can't measure those timings, because any latency could come from the originating computer, the links in the middle or any combination of them. Also precise timings can be limited by fluctuating load averages amongst other things in a time-sharing computing environment. While this might work in a lab, with the current advances in computing speed, the differences between a fast and a slow calculation can easily be opaqued by network lag. Am I missing something, or does this attack only work in a lab? Ben. ____ Ben Samman..............................................samman@cs.yale.edu "If what Proust says is true, that happiness is the absence of fever, then I will never know happiness. For I am possessed by a fever for knowledge, experience, and creation." -Anais Nin PGP Encrypted Mail Welcomed Finger samman@powered.cs.yale.edu for key