sq3 - k 1 ) …, k n = h ( k n-1 ) • Passwords used in...

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Solution Quiz 3 1) F F T T F 2) Dictionary attack: Trial and error guessing Type 1: attacker knows A , F , C. Guess g and compute f ( g ) for each f in F Type 2: attacker knows A , l. l returns True for guess g 3) Speaker-verification (identity) or speaker-recognition (info content) 4) User chooses an initial seed k Key generator calculates: k 1 = h ( k ), k 2 = h (
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Unformatted text preview: k 1 ) …, k n = h ( k n-1 ) • Passwords used in the order: p 1 = k n , p 2 = k n-1 , …, p n = k 1 • Suppose p 1 = k n is intercepted; the next password is p 2 = k n-1. Since h ( k n-1 ) = k n , the attacker needs to invert h to determine the next password. This is not an easy task since h is a one-way function....
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This note was uploaded on 02/07/2012 for the course SIS 2150 taught by Professor Joshi during the Fall '11 term at Pittsburgh.

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