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Ronald Cramer

Professor, Mathematical Institute, Leiden University
Head of the Cryptology and Information Security Research Group, CWI

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Mail address:

Prof. dr. R. Cramer
CWI
Kruislaan 413
P.O. Box 94079
1090 GB Amsterdam, The Netherlands

Email: cramer (at) cwi.nl, cramer (at) math.leidenuniv.nl
Tel: +31-20-592 4166
Fax: +31-20-592 4199

Research Interests

Cryptology: foundations, mathematical aspects, applications.

Computational number theory and geometry, algorithms, discrete mathematics.

Some Professional Activities

  1. Editorial Board Member:
    1. Journal of Cryptology (Springer Verlag)
    2. Information Security and Cryptology Book Series (advisory board, Springer Verlag)
    3. Proceedings Information Security (IEE)
    4. Journal of Mathematical Cryptology (de Gruyter).

  2. Program Chair :
    1. 24th Annual IACR EUROCRYPT, 2005
    2. 11th Annual IACR PKC, 2008

  3. General Chair : 4th Annual IACR TCC, 2007

  4. Program Committee Member : CRYPTO '04, '03, '00, '99, EUROCRYPT '05, '03, '00,
    PKC '08, Theory of Cryptography Conference (TCC '04), ICALP '06, '98, RSA-CT '04, ...

    Director, International Association for Cryptologic Research (IACR) 2004--2007


Short cv

Position:
2004-present: Head of the Cryptology and Information Security Research Group, CWI
2004-present: Full Professor (Chair in Cryptology), Mathematical Institute, Leiden University

Past affiliations:
2000-2004: Aarhus University, BRICS & Computer Science Department, Associate Professor.
1997-2000: ETH Zurich, Institute for Theoretical Computer Science, Senior Researcher.
1992-1997: CWI, Researcher.

Degrees:
Ph.D., University of Amsterdam (Jan. 1997), M.Sc. in Pure Maths., Leiden University (Aug. 1992).

Awards and Honors:
2006 NWO VICI Award
2004 Elected Junior Member of Royal Netherlands Academy of Arts and Sciences (DJA/KNAW).
1998 KNAW Christiaan Huygens Award

Courses

  1. Information Theory, Coding and Cryptology , Mathematical Institute, Leiden University, Fall 2008. (Jointly with S. Fehr)

  2. Cryptology , National Course (Dutch National Master Program in Mathematics), Spring 2008. (Jointly with S. Fehr, E. Kiltz, and B. Schoenmakers)

  3. Topics in Mathematical Cryptology , Mathematical Institute, Leiden University, Spring Semester 2006.

  4. Algebraic, Number Theoretical and Combinatorial Aspects of Secure Computation, Ecole Normale Superieure, Paris, France, March/April 2006.

  5. Number Theory/Cryptology , Dutch National Master's Program in Mathematics. Fall 2005, Department of Mathematics, Utrecht University.

  6. Cryptographic Protocol Theory, undergraduate course (jointly with Ivan Damgaard), Comp. Sc. Dept., Aarhus University, Spring semester 2004, 2003, 2002, 2001.

  7. Mathematics of Secure Multi-Party Computation , course (10 x 60 min.) NTT Research Labs, Yokosuka, Japan, January 2003.

  8. Mathematics of Secure Multi-Party Computation and Public Key Encryption, PhD-course (20 x 60 min.), Maths. Dept., UPC Barcelona, Spain, January 2003.

  9. Topics in Theoretical Cryptology, BRICS PhD-School, Aarhus University, winter semester 2002, winter semester 2001.

  10. Public Key Encryption Secure Against Adaptively Chosen Ciphertext Attack, short PhD-course (6 x 45 min.), Maths. Dept., University of Dortmund, Germany, November 2001.

  11. Introduction to Secure Multi-Party Computation, short PhD-course (6 x 45 min.), Maths. Dept., University of Dortmund, Germany, July 2001, Maths. Dept.

  12. Advanced Cryptographic Protocols, undergraduate course, ETH Zurich, spring semester 1999.


Publications

  1. H. Chen, R. Cramer, C. Ding, C. Xing: Secret Sharing and Secure Multi-Party Computation from Projective Algebraic Sets. Manuscript, 2006.

  2. H. Chen, R. Cramer, R. de Haan, I. Cascudo Pueyo. Ramp schemes with multiplication from high degree rational points on curves.
    In: Proceedings of 27th Annual IACR EUROCRYPT, Istanbul, Turkey, Springer Verlag LNCS, vol. 4965, pp. 451--470, April 2008.

  3. R. Cramer, Y. Dodis, S. Fehr, C. Padro', D. Wichs. Detection of Algebraic Manipulation with Applications to Robust Secret Sharing and Fuzzy Extractors.
    In: Proceedings of 27th Annual IACR EUROCRYPT, Istanbul, Turkey, Springer Verlag LNCS, vol. 4965, pp. 471--488, April 2008.

  4. R. Cramer (Ed.). Proceedings of 11th Annual IACR PKC. Springer Verlag LNCS, vol. 4939, 396p., March 2008.

  5. R. Cramer, D. Hofheinz, E. Kiltz, R. Pass, a. shelat, V. Vaikuntanathan. Bounded CCA2-Secure Encryption.
    In: Proceedings of 13th Annual IACR ASIACRYPT, Malaysia, Springer Verlag LNCS, vol. 4833, pp. 502--518, December 2007.

  6. R. Cramer, E. Kiltz, and C. Padro'. A Note on Secure Computation of the Moore-Penrose Pseudo-Inverse and its Application to Secure Linear Algebra.
    In: Proceedings of 27th Annual IACR CRYPTO, Santa Barbara, Ca., USA, Springer Verlag LNCS, vol. 4622, pp. 613--630, August 2007.

  7. H. Chen, R. Cramer, S. Goldwasser, R. de Haan, V. Vaikuntanathan. Secure Computation from Random Error Correcting Codes.
    In: Proceedings of 26th Annual IACR EUROCRYPT, Barcelona, Spain, Springer Verlag LNCS, vol. 4515, pp. 329--346,May 2007.

  8. R. Cramer, I. Damgaard, R. de Haan. Atomic Secure Multiplication with Low Communication.
    In: Proceedings of 26th Annual IACR EUROCRYPT, Barcelona, Spain, Springer Verlag LNCS, vol. 4515, pp. 291--310,May 2007.

  9. H. Chen and R. Cramer: Algebraic Geometric Secret Sharing Schemes and Secure Multi-Party Computation over Small Fields.
    In: Proceedings of 26th Annual IACR CRYPTO, Santa Barbara, Ca., USA, Springer Verlag LNCS, vol. 4117, pp. 516--531, August 2006.

  10. S. Agarwal, R. Cramer, and R. de Haan: Asymptotically Optimal Perfectly Secure Message Transmission.
    In: Proceedings of 26th Annual IACR CRYPTO, Santa Barbara, Ca., USA, Springer Verlag LNCS, vol. 4117, pp. 389--401, August 2006.

  11. R. Cramer, S. Fehr, M. Stam: Primitive Sets over Number Fields and Black-Box Secret Sharing.
    In: Proceedings of 25th Annual IACR CRYPTO, Santa Barbara, Ca., USA, Springer Verlag LNCS, vol. 3621, pp. 344--360, August 2005.

  12. R. Cramer, V. Daza, I. Gracia, J. Jimenez Urroz, G. Leander, J. Marti-Farre, C. Padro': On Codes, Matroids and Secure Multi-Party Computation from Linear Secret Sharing Schemes .
    In: Proceedings of 25th Annual IACR CRYPTO, Santa Barbara, Ca., USA, Springer Verlag LNCS, vol. 3621, pp. 327--343, August 2005.

  13. R. Cramer, I. Damgaard: Introduction to Secure Multi-Party Computations .
    In: Contemporary Cryptology (Catalano/Cramer/Damgaard/DiCrescenzo/Pointcheval/Takagi), Advanced Courses in Mathematics CRM Barcelona, Birkhauser, 2005 VIII, 237p., 2005.

  14. R. Cramer (Ed.). Proceedings of 24th Annual IACR EUROCRYPT '05 , Springer Verlag LNCS, vol. 3494, 576p., May 2005.

  15. R. Cramer, I. Damgaard, Y. Ishai: Share Conversion, Pseudorandom Secret-Sharing and Applications to Secure Computation .
    In: Proceedings of IACR Theory of Cryptography Conference (TCC '05), MIT, Boston, USA, Springer Verlag LNCS, vol. 3378, pp. 342--362, February 2005.

  16. R. Cramer, I. Damgaard: Secret-Key Zero-Knowledge and Non-Interactive Verifiable Exponentiation .
    In: Proceedings of IACR Theory of Cryptography Conference (TCC '04), MIT, Boston, USA, Springer Verlag LNCS, vol. 2951, pp. 223-237, February 2004.

  17. R. Cramer and V. Shoup: Design and Analysis of Practical Public-Key Encryption Schemes Secure against Adaptive Chosen Ciphertext Attack.
    In: SIAM Journal on Computing 33:167--226, 2003.

  18. R. Cramer, S. Fehr, Y. Ishai, E. Kushilevitz: Secure Multi-Party Computation over Rings .
    In: Proceedings of 22nd Annual IACR EUROCRYPT, Warsaw, Poland, Springer Verlag LNCS, vol. 2656, pp. 596--613, May 2003.

  19. M. Abe, R. Cramer, S. Fehr: Non-Interactive Distributed Verifier Proofs Proving Relations among Commitments in a Distributed Setting.
    In: Proceedings of IACR ASIACRYPT '02, Queenstown, New Zealand, Springer Verlag LNCS, vol. 2501, pp. 206-223, December 2002.

  20. R. Cramer and S. Fehr: Optimal Black-Box Secret Sharing over Arbitrary Abelian Groups.
    In: Proceedings of 22nd Annual IACR CRYPTO, Santa Barbara, Ca., USA, Springer Verlag LNCS, vol.\ 2442, pp.\ 272--287, August 2002.

  21. R. Cramer and V. Shoup: Universal Hash Proofs and a Paradigm for Adaptive Chosen Ciphertext Secure Public-Key Encryption.
    In: Proceedings of 21st Annual IACR EUROCRYPT, Amsterdam, The Netherlands, Springer Verlag LNCS, vol.\ 2332, pp.\ 45--64, April 2002. Long version here

  22. R. Cramer and I. Damgaard: Secure Distributed Linear Algebra in Constant Number of Rounds.
    In: Proceedings 21st Annual IACR CRYPTO '01, Santa Barbara, Ca., USA, Springer Verlag LNCS, vol. 2139, pp. 119--136, August 2001.

  23. R. Cramer, I. Damgaard, S. Fehr: On the Cost of Reconstructing a Secret-- Or: VSS with Optimal Reconstruction.
    In: Proceedings of 21st Annual IACR CRYPTO, Santa Barbara, Ca., USA, Springer Verlag LNCS, vol. 2139, pp. 503--523, August 2001.

  24. R. Cramer, I. Damgaard, J. B. Nielsen: Multi-Party Computations from Threshold Homomorphic Encryption.
    In: Proceedings of 20th Annual IACR EUROCRYPT, Innsbruck, Austria, Springer Verlag LNCS, vol. 2045, pp. 280--300, May 2001.

  25. R. Cramer, I. Damgaard, S. Dziembowski: On the Complexity of Verifiable Secret Sharing and Multi-Party Computation.
    In: Proceedings of the 32nd Annual ACM Symposium on Theory of Computing (STOC '00), Portland, Oregon, USA, ACM Press, pp. 325--334, May 2000.

  26. R. Cramer, I. Damgård and U. Maurer: Efficient General Secure Multi-Party Computation from any Linear Secret-Sharing Scheme.
    In: Proceedings of 19th Annual IACR EUROCRYPT, Brugge, Belgium, Springer Verlag LNCS, vol. 1807, pp. 316--334, May 2000. Long version

  27. R. Cramer, I. Damgaard and P. MacKenzie: ZK for Free: The Case of Proofs of Knowledge..
    In: Proceedings of Public Key Cryptography (PKC2000), Melbourne, Australia, Springer Verlag LNCS, vol. 751, pp.354--372, January 2000.

  28. R. Cramer, V. Shoup: Signature schemes based on the Strong RSA Assumption.
    In: Proceedings of 6th ACM Conference on Computer and Communications Security, Singapore, Thailand, November 1999. Journal version in ACM Transactions on Information and System Security (ACM TISSEC) 3(3):161-185, 2000.

  29. R. Cramer, I. Damgaard, S. Dziembowski, M. Hirt, T. Rabin, Efficient Multi-Party Computations with Dishonest Majority.
    In: Proceedings of 18th Annual IACR EUROCRYPT, Prague, Czech Republic, Springer Verlag LNCS, vol. 1592, pp. 311--326, May 1999.

  30. R. Cramer: Introduction to Secure Computation.
    In: Lectures on Data Security - Modern Cryptology in Theory and Practice, Ivan Damgaard (Ed.), Springer LNCS Tutorial, vol.1561, March 1999, pp. 16-62. Revised version is available here, January 2000.

  31. R. Cramer, V. Shoup: A Practical Public Key Cryptosystem Provably Secure against Adaptive Chosen Ciphertext Attack .
    In: Proceedings of 18th Annual IACR CRYPTO, Santa Barbara, Ca., USA, Springer Verlag LNCS, vol. 1462, pp. 13--25, August 1998.

  32. R. Cramer, I. Damgård: Zero-Knowledge for Finite Field Arithmetic. Or: Can Zero-Knowledge be for Free?.
    In: Proceedings 18th Annual IACR CRYPTO, Santa Barbara, Ca., USA, Springer Verlag LNCS, vol. 1462, pp. 424--441, August 1998.

  33. R. Cramer and I. Damgård: Linear Zero-Knowledge: A Note on Efficient Zero-Knowledge Proofs and Arguments.
    In: Proceedings of 29th Annual ACM Symposium on Theory of Computing (STOC '97), El Paso, Texas, USA, ACM Press, pp. 436--445, May 1997.

  34. R. Cramer and I. Damgård: Fast and Secure Immunization against Man-in-the-Middle Impersonations.
    In: Proceedings of 16th Annual IACR EUROCRYPT, Konstanz, Germany, Springer Verlag LNCS, vol. 1233, pp. 75--87, May 1997.

  35. R. Cramer, R. Gennaro and B. Schoenmakers: A Secure and Optimally Efficient Multi-Authority Election Scheme.
    In: Proceedings of EUROCRYPT '97, Konstanz, Germany, Springer Verlag LNCS, vol. 1233, pp. 103--118, May 1997. Journal version: Eur. Trans. Telecom, Vol. 8, No. 5, Sept./Oct. 1997, pp. 481--490.

  36. R. Cramer: Modular Design of Secure yet Practical Cryptographic Protocols , Ph.D.-thesis, CWI and Uni.of Amsterdam, November 1996. 1998 Christiaan Huygens Award of Royal Netherlands Academy of Sciences (KNAW). .

  37. R. Cramer, I. Damgård : New Generation of Secure and Practical RSA-based Signatures.
    In: Proceedings of 16th Annual IACR CRYPTO, Santa Barbara, Ca., USA, Springer Verlag LNCS, vol. 1109, pp. 173--185, August 1996.

  38. R. Cramer, I. Damgård, and T. P. Pedersen: Efficient and Provable Security Amplifications.
    In: Proceedings of 4th Cambridge Security Protocols Workshop, Cambridge, UK, Springer Verlag LNCS, vol. 1189, pp. 101--109, April 1996.

  39. R. Cramer, M. Franklin, B. Schoenmakers, M. Yung: Secure Secret Ballot Election Schemes with Linear Work.
    In: Proceedings of 15th Annual IACR EUROCRYPT, Zaragoza, Spain, Springer Verlag LNCS, vol. 1070, pp. 72--83, May 1996.

  40. J. Boly et al., ESPRIT 7023 Conditional Access for Europe (CAFE), Final Report Secure Protocols. CWI Technical Report, 1996.

  41. I. Damgård, R. Cramer: On Monotone Function Closure of Perfect and Statistical Zero-Knowledge, CWI technical report, CS-R9618, May 1996.

  42. R. Cramer: On Shared Randomness and the Size of Secure Signatures, CWI Technical Report CS-R9530, April 1995

  43. R. Cramer, I. Damgård: Secure Signature Schemes based on Interactive Protocols.
    In: Proceedings of 15th Annual IACR CRYPTO, Santa Barbara Ca., Springer Verlag LNCS, vol. 963, pp. 297--310, August 1995.

  44. R. Cramer, I. Damgård, B. Schoenmakers: Proofs of Partial Knowledge and Simplified Design of Witness Hiding Protocols.
    In: Proceedings of 14th Annual IACR CRYPTO, Santa Barbara Ca., Springer Verlag LNCS, vol. 839, pp. 174--187, August 1994.

  45. J. -P. Boly et al.: The ESPRIT Project CAFE - High Security Digital Payment Systems.
    In: Proceedings of ESORICS 94, Springer Verlag LNCS, vol. 875, pp. 217-230, 1994.

  46. J. -P. Boly et al.: Digital Payment Systems in the ESPRIT Project CAFE , Securicom 94, Paris 1.-3.6.1994, 35-45.

  47. R. Cramer and T. Pedersen: Improved Privacy in Wallets with Observers.
    In: Proceedings of 12th Annual IACR EUROCRYPT, Lofthus, Norway, Springer Verlag LNCS, vol. 765, pp. 329--343, May 1993.


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