Yiqun Lisa Yin is a Chinese-American cryptographer and independent security consultant. Yin is known for breaking the

SHA-1 In cryptography, SHA-1 (Secure Hash Algorithm 1) is a cryptographically broken but still widely used hash function which takes an input and produces a 160-bit (20-byte) hash value known as a message digest – typically rendered as 40 hexadecima ...

cryptographic hash function A cryptographic hash function (CHF) is a hash algorithm (a map of an arbitrary binary string to a binary string with fixed size of n bits) that has special properties desirable for cryptography: * the probability of a particular n-bit output re ...

, for developing the

RC6 In cryptography, RC6 (Rivest cipher 6) is a symmetric key block cipher derived from RC5. It was designed by Ron Rivest, Matt Robshaw, Ray Sidney, and Yiqun Lisa Yin to meet the requirements of the Advanced Encryption Standard (AES) competition. ...

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 ...

, and for her service as editor of the

IEEE P1363 IEEE P1363 is an Institute of Electrical and Electronics Engineers (IEEE) standardization project for public-key cryptography. It includes specifications for: * Traditional public-key cryptography (IEEE Std 1363-2000 and 1363a-2004) * Lattice-ba ...

project for the standardization of

public-key cryptography Public-key cryptography, or asymmetric cryptography, is the field of cryptographic systems that use pairs of related keys. Each key pair consists of a public key and a corresponding private key. Key pairs are generated with cryptographic alg ...

Education and career

Yin was a student at

Peking University Peking University (PKU; ) is a public research university in Beijing, China. The university is funded by the Ministry of Education. Peking University was established as the Imperial University of Peking in 1898 when it received its royal charter ...

from 1985 to 1989, and earned a bachelor's degree in applied mathematics there. She went to the

Massachusetts Institute of Technology The Massachusetts Institute of Technology (MIT) is a private land-grant research university in Cambridge, Massachusetts. Established in 1861, MIT has played a key role in the development of modern technology and science, and is one of the ...

for graduate study, and completed her Ph.D. there in applied mathematics in 1994. Her dissertation, ''Teaching, Learning, and Exploration'', concerned

computational learning theory In computer science, computational learning theory (or just learning theory) is a subfield of artificial intelligence devoted to studying the design and analysis of machine learning algorithms. Overview Theoretical results in machine learning m ...

and

online algorithm In computer science, an online algorithm is one that can process its input piece-by-piece in a serial fashion, i.e., in the order that the input is fed to the algorithm, without having the entire input available from the start. In contrast, an o ...

s; it was supervised by

Michael Sipser Michael Fredric Sipser (born September 17, 1954) is an American theoretical computer scientist who has made early contributions to computational complexity theory. He is a professor of applied mathematics and was the Dean of Science at the Massa ...

. She worked as a researcher at

RSA Laboratories RSA Security LLC, formerly RSA Security, Inc. and doing business as RSA, is an American computer and network security company with a focus on encryption and encryption standards. RSA was named after the initials of its co-founders, Ron Rivest, ...

from 1994 to 1999, and as director of security technologies at NTT's Palo Alto Laboratory for Multimedia Communications from 1999 to 2002, before becoming an independent consultant. She also worked as a visiting researcher at

Princeton University Princeton University is a private university, private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial Colleges, fourth-oldest ins ...

and

Tsinghua University Tsinghua University (; abbreviation, abbr. THU) is a National university, national Public university, public research university in Beijing, China. The university is funded by the Ministry of Education of the People's Republic of China, Minis ...

. From 2016 to 2019, Yin was the chief security officer and chief cryptographer of Symbiont.

Contributions

Yin was the editor of the

project for the standardization of

. With

Ron Rivest Ronald Linn Rivest (; born May 6, 1947) is a cryptographer and an Institute Professor at MIT. He is a member of MIT's Department of Electrical Engineering and Computer Science (EECS) and a member of MIT's Computer Science and Artificial Intell ...

Matt Robshaw Matthew John Barton "Matt" Robshaw is a cryptographer. Formerly a lecturer at Royal Holloway, University of London and a member of the cryptography research group at France Telecom's Orange Labs, he is now a Technical Fellow at Impinj. He coordina ...

, and Ray Sidney, she was one of the designers of

, a

with

symmetric key Symmetric-key algorithms are algorithms for cryptography that use the same cryptographic keys for both the encryption of plaintext and the decryption of ciphertext. The keys may be identical, or there may be a simple transformation to go between th ...

s that was one of five finalists for the 1997–2000

Advanced Encryption Standard competition The Advanced Encryption Standard (AES), the symmetric block cipher ratified as a standard by National Institute of Standards and Technology of the United States (NIST), was chosen using a process lasting from 1997 to 2000 that was markedly more ...

. In 2005, with

Wang Xiaoyun Wang Xiaoyun (; born 1966) is a Chinese cryptographer, mathematician, and computer scientist. She is a professor in the Department of Mathematics and System Science of Shandong University and an academician of the Chinese Academy of Sciences. Ear ...

and Hongbo Yu, Yin demonstrated an unexpected high probability of

collisions In physics, a collision is any event in which two or more bodies exert forces on each other in a relatively short time. Although the most common use of the word ''collision'' refers to incidents in which two or more objects collide with great f ...

(two different data values with the same hash) in the

, originally designed by the

National Security Agency The National Security Agency (NSA) is a national-level intelligence agency of the United States Department of Defense, under the authority of the Director of National Intelligence (DNI). The NSA is responsible for global monitoring, collecti ...

. Their work caused SHA-1 to be considered as broken, and it has since fallen out of use.

References

External links

Home page at MIT
* {{DEFAULTSORT:Yin, Yiqun Lisa Year of birth missing (living people) Living people Chinese mathematicians 20th-century American mathematicians 21st-century American mathematicians American women mathematicians American cryptographers Chinese cryptographers Peking University alumni Women cryptographers 20th-century American women 21st-century American women