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25 lines
535 B
Markdown
25 lines
535 B
Markdown
---
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title: "passwords"
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aliases:
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tags:
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- comp210
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---
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# Passwords
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- not good
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- lots of bad advice
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- we are lazy
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- "safe" passwords are difficult to enter on touch screen devices
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- to many accouts
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## entropy
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- amount of randomness
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- measure of the number of guesse an attacker would need to brute foarce
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- $E = log_2(A^L)$
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- A = size of alphabet
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- L = length of password
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- E = entropy in bits
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- 80 bits is "safe"
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- would take decades
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- 6 digits passoword - 29 bits (took 4 seconds to brute force)
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- + uppercase and numbers - 36 bits |