Jim Miller writes :
Assume you use strong crypto to protect your secrets.
Assume a lot of people start using crypto to protect their secrets.
Assume there are people who want to discover these secrets.
Might we some day see an increase in the number physical attacks as bad guys resort to rubber-hose methods to get at the keys that protect the secrets?
I think this phenomenon is more or less inevitable, unless serious thought is given to a way to prevent it. Let's take a simple example and progress to a more complex scenario: If I want your money, I could steal your ATM card and try to deduce the PIN number (tough), or I could wait in the bushes with a .44 until you use the ATM and either steal the money you get out (easy) or convince you to tell me the PIN number (harder, although a .44 is remarkably persuasive). However, it's easy for you to lock me out of your accounts by changing the PIN number the next day - to get continued access to your account, I'd have to get the PIN number and then kill you (begging your pardon, of course). Even if I did all that, all I'd have is a bank account. Hardly worth it. If I want your *life* (metaphorically speaking; your network connections, your digicash, your 'reputation capital', etc.) and all I have to do to get it is beat your PGP pass phrase out of you and kill you afterwards, you're in much more danger. I could lie in wait, get your pass phrase, (ahem) remove the evidence, and step into your net.shoes the next day. Bottom line: As the value protected by our encryption systems increases, we must devote more effort to the solution of problems like the thug with the .44 (or the jealous co-worker; insert favorite bogey-man here) who wants our password. Key revocation certificates are nice, for example, assuming you are able to issue one - 'dead men revoke no keys,' however. Duress codes seem like a better deal; even though the enemy may kill you after you give him a code that (seemingly) works, your 'estate' would be protected. What we *really* need is a hat trick that makes strong-arm tactics useless - any ideas? When the tactic of beating a pass phrase out of a citizen becomes as stupid as killing for a PIN number, we'll know we've succeeded. <Shudder> Damn! My coffee's gone cold. I'm off to get a refill- talking about killing people has given me a definite chill. Not my favorite topic. ........................................................................ Philippe D. Nave, Jr. | The person who does not use message encryption pdn@dwroll.dw.att.com | will soon be at the mercy of those who DO... Denver, Colorado USA | PGP public key: by arrangement.