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3 Password Length in Characters Low Complexity: Alphabetic, No Case (N=26) Alphabetic, Case-Sensitive (N=52) Alphanumeric: Letters and Digits (N=62) High Complexity: All Keyboard Characters (N=80) ,7043,8446, ,9767,311,61614,776,33640,960, ,915,77619,770,609, ,800,235, E E E E E E E E E+19 Note: On average, an attacker will have to try half of all combinations.

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Use Password Manager 1Password Roboform Password Based Key Derivation Function Version 2 (PBKDFV2) Systems using PBKDFV2 Copyright Pearson Prentice-Hall

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ItemMean Number of Sites105.7 Number of Unique IDs6.6 Number of Unique passwords4.7 Number of Unique log-in credentials11.8 ID re-use ratio19.1 Password re-use ratio29.2 Log-in credentials re-use10.5 % of used unique log-in credentials45.6%

ItemMean Inclusiveness0.94Use the same log-in credentials Largest component nd largest component (cumulative) 3 rd largest component (cumulative) Vulnerability Index most frequently used log-in combinations use in 81% of sites vs unique log-in credentials VI = expected proportion of sites subject to potential breaches if a breach at one site occurs Larger values of VI indicate higher levels of vulnerability