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A comment on Don't use 1234 as your password. Parent comment

Re:Don't use 1234 as your password by vezzy-fnord on Sunday November 17, 2013 @07:46PM (#6751837)
No, no. It was 12345. An extra bit of security.
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Re:Don't use 1234 as your password by foobarian on Sunday November 17, 2013 @08:05PM (#6751910)
Pardon me, but 12345 is 3 extra bits.
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Re:Don't use 1234 as your password by GhotiFish on Sunday November 17, 2013 @08:49PM (#6752049)
explain.
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Re:Don't use 1234 as your password by sillysaurus2 on Sunday November 17, 2013 @08:55PM (#6752071)
When the password consists of 4 characters, each being 0-9, there are 10,000 possible passwords; 14 bits are required to represent 10,000 possible combinations of anything:

  log(10000) / log(2) == 13.28771
With 5 characters, each 0-9, there are 100,000 possible combinations, and that requires 17 bits:

  log(100000) / log(2) == 16.60964
Therefore, 12345 offers 3 extra bits of security compared to 1234.
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Re:Don't use 1234 as your password by vezzy-fnord on Sunday November 17, 2013 @08:52PM (#6752060)
He's right. Decimal 5 is binary 101, hence 3 bits.

I wasn't literally referring to data bit, though. But he has a point.

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Re:Don't use 1234 as your password by joe_inferno on Sunday November 17, 2013 @09:08PM (#6752106)
yeah, that's not why, but good enough I guess.
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