Seminars at the Faculty of Informatics

The Faculty of Informatics is pleased to announce a seminar given by Yevgeniy Dodis


TITLE: Basing Cryptography on Biometrics and Other Noisy Data

SPEAKER: Yevgeniy Dodis, NYU

DATE: Thursday, June 12th, 2008

PLACE: USI Università della Svizzera italiana, room SI-006, Informatics building (Via G. Buffi 13)

TIME: 10.30-11.30



We provide formal definitions and efficient secure techniques for


-- turning biometric information into keys usable for any

    cryptographic application, and


-- reliably and securely authenticating biometric data.


Our techniques apply not just to biometric information, but to any keying material that, unlike traditional cryptographic keys, is (1) not reproducible precisely and (2) not distributed uniformly. We propose two new primitives.


-- A *fuzzy extractor* extracts nearly uniform randomness R from its

    biometric input; the extraction is error-tolerant in the sense that

    R will be the same even if the input changes, as long as it remains

    reasonably close to the original. Thus, R can be used as a key in

    any cryptographic application.


-- A *secure sketch* produces public information about its biometric

    input w that does not reveal w, and yet allows exact recovery of w

    given another value that is close to w. Thus, it can be used to

    reliably reproduce error-prone biometric inputs without incurring

    the security risk inherent in storing them.


In addition to formally introducing our new primitives, we provide nearly optimal constructions of both primitives for various measures of "closeness" of input data.


If time permits, some follow-up work will be mentioned. The talk will be introductory and self-contained. Original paper can be found at and a recent survey can be found at




Yevgeniy Dodis is an Associate Professor of computer science at New York University. Dr. Dodis received his summa cum laude Bachelors degree in Mathematics and Computer Science from New York University in 1996, and his PhD degree in Computer Science from MIT in 2000.

Dr. Dodis was a post-doc at IBM T.J.Watson Research center in 2000, and joined New York University as an Assistant Professor in 2001.


Dr. Dodis' research is primarily in cryptography and network security.

In particular, he worked in a variety of areas including exposure-resilient cryptography, cryptography and imperfect randomness, cryptography with biometrics and other noisy data, authenticated encryption, hash functions and information-theoretic cryptography. Dr. Dodis has more than 70 scientific publications at various conferences, journals and other venues, has been on program committees of many international conferences (including FOCS, STOC, CRYPTO and Eurocrypt), and gave numerous invited lectures and courses at various venues.


Dr. Dodis is the recipient of National Science Foundation CAREER Award, IBM Faculty Award and Best Paper Award at 2005 Public Key Cryptography Conference. As an undergraduate student, he was also a winner of the US-Canada Putnam Mathematical Competition.

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