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A Cryptanalytic View of the NSA’s Skipjack Block Cipher Design

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Advances in Information Security and Assurance (ISA 2009)

Part of the book series: Lecture Notes in Computer Science ((LNSC,volume 5576))

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Abstract

Skipjack is a block cipher designed by the NSA for use in US government phones, and commercial mobile and wireless products by AT&T. Among its initial implementations in hardware were the Clipper chip and Fortezza PC cards, which have since influenced the private communications market to be compatible with this technology. For instance, the Fortezza card comes in PCMCIA interface and is a very easy plug-n-play device to add on to mobile and wireless systems to provide encryption for wireless transmissions. Initially classified when it was first proposed, Skipjack was declassified in 1998 and sparked numerous security analyses from security researchers worldwide because it provides insight into the state-of-the-art security design techniques used by a highly secretive government intelligence agency such as the NSA. In this paper, commemorating over a decade since Skipjack’s public revelation, we revisit the security of Skipjack against cryptanalytic results and discuss why certain attack approaches fare better with reference to Skipjack’s design structure.

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Author information

Authors and Affiliations

  1. Center for Information Security Technologies (CIST), Korea University, Anam Dong, Sungbuk Gu, Seoul, Korea

    Jongsung Kim

  2. Electronic & Electrical Engineering Department, Loughborough University, LE11 3TU, United Kingdom

    Raphael C. -W. Phan

Authors
  1. Jongsung Kim
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  2. Raphael C. -W. Phan
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Editor information

Editors and Affiliations

  1. Computer Engineering Department, Kyungnam University, 449, Wolyong-dong, 631-701, Kyungnam, Masan, Korea

    Jong Hyuk Park

  2. Institute of Communications Engineering, National Sun Yat-Sen University, Kaohsiung City, Taiwan

    Hsiao-Hwa Chen

  3. School of Computer Science,, University of Oklahoma, 200 Felgar Street, 73019, P.O. Box, Norman, OK, USA

    Mohammed Atiquzzaman

  4. School of Computer Engineering, Hanshin University, Kyeong-Gi, Osan, Korea

    Changhoon Lee

  5. Division of Multimedia, Hannam University, Daejeon, Korea

    Tai-hoon Kim

  6. Division of Computer Engineering, Mokwon University, Daejeon, Korea

    Sang-Soo Yeo

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Kim, J., Phan, R.C.W. (2009). A Cryptanalytic View of the NSA’s Skipjack Block Cipher Design. In: Park, J.H., Chen, HH., Atiquzzaman, M., Lee, C., Kim, Th., Yeo, SS. (eds) Advances in Information Security and Assurance. ISA 2009. Lecture Notes in Computer Science, vol 5576. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-02617-1_38

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  • DOI: https://doi.org/10.1007/978-3-642-02617-1_38

  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-642-02616-4

  • Online ISBN: 978-3-642-02617-1

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