Joe-Kai Tsay

I obtained a Ph.D. in Mathematics from Penn in August'08 and am currently a postdoctoral researcher at the Laboratoire Spécification et Vérification (LSV) of the École Normale Supérieure de Cachan (ENS Cachan), France. My Ph.D. advisor was Andre Scedrov.

Research Interests include:

• Information Security, Formal Methods and Cryptography.

Professional Activities:

• Program Committees
  • 2009 Information Security Conference, ISC 2009, Pisa, Italy, September 7-9, 2009

Publications:

• Journals
  1. Cryptographically Sound Security Proofs for Basic and Public-key Kerberos (with M. Backes, I. Cervesato, A. D. Jaggard, and A. Scedrov)
     International Journal of Information Security, Volume 10, Issue 2 (2011), Springer-Verlag,  2011, pp. 107 –134
  2. Breaking and Fixing Public-Key Kerberos (with I. Cervesato, A. D. Jaggard, A. Scedrov, and C. Walstad)
     Information and Computation 206(2008), Elsevier, 2008, pp. 402–424
     • Work co-responsible for Microsoft Security Bulletin MS05-042 and integrated in Request for Comment RFC 4556 of the Internet Engineering Task Force (IETF)
  
  
• Conferences/workshops
1. Modular Soundness Proofs via Deduction Games (with H. Comon-Lundh, and S. Kremer)
   In: 6th Workshop on Formal and Computational Cryptography (FCC 2010), Edinburgh, UK, July 20, 2010 [Abstract]
2. On the Design and Implementation of Efficient Zero-Knowledge Proofs of Knowledge (with E. Bangerter, S. Krenn, A.-R. Sadeghi and T. Schneider)
   In: ECRYPT workshop on Software Performance Enhancements for Encryption and Decryption and Cryptographic Compilers (SPEED-CC '09), Berlin, Germany, October 12-13, 2009, pp. 93-112 [.pdf]
3. Bringing Zero-Knowledge Proofs of Knowledge to Practice (with E. Bangerter, S. Barzan, S. Krenn, A.-R. Sadeghi, and T. Schneider)
   In: 17th International Workshop on Security Protocols, 2009, Cambridge, UK, pp. 30-42, full version at http://eprint.iacr.org/2009/211
4. Computationally Sound Mechanized Proofs for Basic and Public-key Kerberos (with B. Blanchet, A. D. Jaggard, and A. Scedrov)
   In: ACM Symposium on Information, Computer and Communications Security, ASIACCS 2008, Tokyo, Japan, ACM Press, 2008, pp. 87-99 [.pdf]
   This extends and is refined by the following works
   1. Computationally Sound Mechanized Proofs of PKINIT for Kerberos (with A. D. Jaggard and A. Scedrov)
      In: 3rd Workshop on Formal and Computational Cryptography, FCC 2007, Venice, Italy, to appear [.pdf]
   2. Refining Computationally Sound Mechanized Proofs for Kerberos (with B. Blanchet, A. D. Jaggard, J. Rao, and A. Scedrov)
      In: R. Kuesters, ed., 5th Workshop on Formal and Computational Cryptography (FCC 2009), Port Jefferson, New York, USA, July 2009 [.pdf]
5. Cryptographically Sound Security Proofs for Basic and Public-key Kerberos (with M. Backes, I. Cervesato, A. D. Jaggard, and A. Scedrov)
   In: A. Gollmann, J. Meier, and A. Sabelfeld, eds., Computer Security – ESORICS 2006, 11th  European Symposium On Research In Computer Security, Springer LNCS, Volume 4189, 2006, pp. 362 - 383 [.pdf]
   Expanded version on Cryptology ePrint Archive: http://eprint.iacr.org/2006/219  
6. Breaking and Fixing Public-Key Kerberos (with I. Cervesato, A. D. Jaggard, A. Scedrov, and C. Walstad)
   In: M. Okada, I. Satoh, eds., 11th  Annual Asian Computing Science Conference, ASIAN 2006, Tokyo, Japan, Springer LNCS, Volume 4435, 2008, pp. 167- 181 [.pdf]
   This extends thefollowing work:
   1. Breaking and Fixing Public-Key Kerberos (with I. Cervesato, A. D. Jaggard, A. Scedrov, and C. Walstad)
      In: Sixth Workshop on Issues in the Theory of Security - WITS'06 (Dieter Gollmann and Jan Juerjens, editors), pp. 55-70, Vienna, Austria, 25-26 March 2006.


• Thesis
  • Formal Analysis of the Kerberos Authentication Protocol [.pdf]

Before attending the University of Pennsylvania I studied Mathematics at the University of Essen, Germany. My advisor there was Henning Stichtenoth and the title of my Diplomarbeit (M.A. thesis) was Geometrische Goppa-Codes und verallgemeinerte Produktcodes (Geometric Goppa Codes and Generalized Product Codes) [.pdf (in German)].