04-17-2013, 04:58 AM
(04-17-2013, 02:44 AM)jpgoldberg Wrote: Remember that unlike the passwords that 1Password saves for people, the Master Password has to be memorable and typable by humans. If one uses a diceware password phrase (as we recommend to 1Password users) then a three word pass phrase has a mean time to crack of 22 hours. A four word one has 19 years, five words is 150,000 years. After that it is millions of years.
In other words, this does change the kind of advice we have to give users. Please keep in eye on the AgileBits blog for more details.
What dictionary sizes are you assuming for the various passphrases?
I would also note that you appear to be ignoring Moore's Law in your time estimates, much like this old article did: http://www.garykessler.net/library/password.html
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