Passwords are crypto-based

• If your password ‘P’ is JsNd4%j^

  • how guessable is it?

• In the space of all passwords:

  • say it’s up to 8 printable characters
  • if chosen at random
  • p(P) is 1/n8 where n is the number of printable symbols
  • Remember Shannon: H(P)=|P| => if n=100, p=1/1016

• If I can guess 1,000,000 times per second, this is still 10 billion second > 2.7M hours > 317 years

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