ISSN : 1796-203X
Volume : 4    Issue : 7    Date : July 2009

Password Generation and Search Space Reduction
Kirsi Helkala and Einar Snekkenes
Page(s): 663-669
Full Text:
PDF (405 KB)

It is easy for humans to design passwords that are easily remembered. However, such passwords
may have a predictable structure, making exhaustive search feasible. We have divided
human-generated passwords into three categories: Non-word passwords, Mixture passwords, and
Word passwords; depending on their overall structure. Within these categories, we have analyzed
the search-space reduction of several common password sub-structures. From this analysis, we
have derived guidelines that yield strong passwords within in each password category. Our results
contribute towards the goal of achieving both strong and memorable passwords.

Index Terms
Password security, password policy, search space reduction, personnel authentication