A Note on Proactive Password Checking
Nowadays, proactive password checking algorithms are based on the philosophy of the dictionary attack, and they often fail to prevent some weak passwords with low entropy. In this paper, a new approach is proposed to deal with this new class of weak passwords by (roughly) measuring entropy. A simple example is given to exploit effective patterns to prevent low-entropy passwords as the first step of entropy-based proactive password checking.
Download the paper in PDF format here.