It's amazing how much someone can determine about a "secure" system by poking at it, doing differential attacks, and timing attacks. Anyone trying to build some

It's amazing how much someone can determine about a "secure" system by poking at it, doing differential attacks, and timing attacks. Anyone trying to build something secure should take warning from this, especially since there are much, much more determined attackers. As someone reverse-engineering the Z-80, I find this article interesting. Maybe 35 years from now, someone will post a full analysis of how this Intel chip processes microcode internally, answering all the questions raised by this article. It will be very interesting to find out if there's anything malicious in any microcode patches. Are there checksums of the microcode so you can make sure you're not getting "special" microcode updates? Reply to mrb: I expect 90% of the purpose of the signature is to protect against untested or corrupted updates getting installed. (It would be a support nightmare if people installed microcode with errors.) Protecting against deliberate attacks is probably secondary; I doubt you could do a nontrivial attack without inside help.