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Title Improving Usability of Passphrase Authentication
Author Nielsen, Glen
Vedel, Michael
Supervisor Jensen, Christian D. (System Security, Department of Informatics and Mathematical Modeling, Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby, Denmark)
Institution Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby, Denmark
Thesis level Master's thesis
Year 2009
Abstract The combination of user-names and passwords has become the predominant method of user authentication in computer systems. Most users have multiple accounts on different systems, which impose different constraints on the length and complexity of passwords the user is allowed to select. This is done to ensure an appropriate degree of security, but instead, it makes it difficult for users to remember their password, which results in passwords that are insecure, but easy to remember, or written down on paper. In this thesis we address the problem of usability in user authentication. We propose to use passphrases, which provide better security and are often easier to remember than passwords. Passphrases will be significantly longer than passwords, which makes them more difficult to enter correctly on a keyboard. We solve this problem by proposing a new passphrase validation algorithm, which accepts the most common typing mistakes to a certain extend. The proposed algorithm has been implemented in secure hardware and integrated into a standard Unix system. We present the design, implementation and evaluation of the developed passphrase authentication system.
Imprint Technical University of Denmark (DTU) : Kgs. Lyngby, Denmark
Series IMM-M.Sc.-2009-25
Original PDF ep09_25_net.pdf (4.62 MB)
Admin Creation date: 2009-05-04    Update date: 2010-10-28    Source: dtu    ID: 242276    Original MXD