Eli Biham ( he, אלי ביהם) is an Israeli

cryptographer Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or '' -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adv ...

and

cryptanalyst Cryptanalysis (from the Greek ''kryptós'', "hidden", and ''analýein'', "to analyze") refers to the process of analyzing information systems in order to understand hidden aspects of the systems. Cryptanalysis is used to breach cryptographic se ...

, currently a professor at the Technion - Israel Institute of Technology Computer Science department. Starting from October 2008 and till 2013, Biham was the dean of the Technion Computer Science department, after serving for two years as chief of CS graduate school. Biham received his Ph.D. for inventing (publicly)

differential cryptanalysis Differential cryptanalysis is a general form of cryptanalysis applicable primarily to block ciphers, but also to stream ciphers and cryptographic hash functions. In the broadest sense, it is the study of how differences in information input can af ...

, while working under

Adi Shamir Adi Shamir ( he, עדי שמיר; born July 6, 1952) is an Israeli cryptographer. He is a co-inventor of the Rivest–Shamir–Adleman (RSA) algorithm (along with Ron Rivest and Len Adleman), a co-inventor of the Feige–Fiat–Shamir identifica ...

. It had, it turned out, been invented at least twice before. A team at IBM discovered it during their work on DES, and was requested/required to keep their discovery secret by the NSA, who evidently knew about it as well.

Contributions to cryptanalysis

Among his many contributions to cryptanalysis one can count: *

- publicly invented during his Ph.D. studies under

* Attacking all triple modes of operation. *

impossible differential cryptanalysis In cryptography, impossible differential cryptanalysis is a form of differential cryptanalysis for block ciphers. While ordinary differential cryptanalysis tracks differences that propagate through the cipher with greater than expected probability, ...

- joint work with

and

Alex Biryukov Alex Biryukov is a cryptographer, currently a full professor at the University of Luxembourg. His notable work includes the design of the stream cipher LEX, as well as the cryptanalysis of numerous cryptographic primitives. In 1998, he developed ...

* Breaking (together with

Lars Knudsen Lars Ramkilde Knudsen (born 21 February 1962) is a Danish researcher in cryptography, particularly interested in the design and analysis of block ciphers, hash functions and message authentication codes (MACs). Academic After some early work i ...

) the ANSI X9.52 CBCM mode (few days before the final standardization) * Breaking the GSM security mechanisms (with Elad Barkan and Nathan Keller) * Co-invention of

related-key attack In cryptography, a related-key attack is any form of cryptanalysis where the attacker can observe the operation of a cipher under several different keys whose values are initially unknown, but where some mathematical relationship connecting the k ...

s. * Differential Fault Analysis - joint work with

New cryptographic primitives

Biham has taken part in the design of several new cryptographic primitives: * Serpent (with Ross Anderson and

), a

block cipher In cryptography, a block cipher is a deterministic algorithm operating on fixed-length groups of bits, called ''blocks''. Block ciphers are specified cryptographic primitive, elementary components in the design of many cryptographic protocols and ...

which was one of the final five contenders to become the

Advanced Encryption Standard The Advanced Encryption Standard (AES), also known by its original name Rijndael (), is a specification for the encryption of electronic data established by the U.S. National Institute of Standards and Technology (NIST) in 2001. AES is a variant ...

Tiger The tiger (''Panthera tigris'') is the largest living cat species and a member of the genus '' Panthera''. It is most recognisable for its dark vertical stripes on orange fur with a white underside. An apex predator, it primarily preys on ...

(with Ross Anderson), a

hash function A hash function is any function that can be used to map data of arbitrary size to fixed-size values. The values returned by a hash function are called ''hash values'', ''hash codes'', ''digests'', or simply ''hashes''. The values are usually ...

fast on 64-bit machines, and * Py (with Jennifer Seberry), one of a family of fast

stream cipher stream cipher is a symmetric key cipher where plaintext digits are combined with a pseudorandom cipher digit stream ( keystream). In a stream cipher, each plaintext digit is encrypted one at a time with the corresponding digit of the keystream ...

s (see article for more detail on their cryptanalytic status). * SHAvite-3 (with

Orr Dunkelman __INDEX__ Orr Dunkelman ( he, אור דונקלמן) is an Israeli cryptographer and cryptanalyst, currently a professor at the University of Haifa Computer Science department. Dunkelman is a co-director of the Center for Cyber Law & Privacy at ...

), a

which was one of the 14 semifinalists in the

NIST hash function competition The NIST hash function competition was an open competition held by the US National Institute of Standards and Technology (NIST) to develop a new hash function called SHA-3 to complement the older SHA-1 and SHA-2. The competition was formally ann ...

External links

Eli Biham's homepage at Technion
{{DEFAULTSORT:Biham, Eli Modern cryptographers Israeli computer scientists Living people Biham Eli Biham Eli Israeli Jews International Association for Cryptologic Research fellows 1960 births