# Malcolm J. Williamson

Malcolm J. Williamson | |
---|---|

Born | ^{[1]}Stockport, United Kingdom | 2 November 1950

Died | 15 September 2015^{[2]}San Diego, United States ^{[3]} | (aged 64)

Nationality | British |

Known for | Independently developed a version of Diffie–Hellman key exchange |

Awards | IEEE Milestone, Cryptologic Hall of Honor |

Scientific career | |

Fields | Cryptography |

**Malcolm John Williamson** (2 November 1950 – 15 September 2015) was a British mathematician and cryptographer. In 1974 he developed what is now known as Diffie–Hellman key exchange.^{[4]} He was then working at GCHQ and was therefore unable to publicise his research as his work was classified. Martin Hellman, who independently developed the key exchange at the same time, received credit for the discovery until Williamson's research was declassified by the British government in 1997.^{[4]}

Williamson studied at Manchester Grammar School, winning first prize in the 1968 British Mathematical Olympiad.^{[5]} He also won a Silver prize^{[6]} at the 1967 International Mathematical Olympiad in Cetinje, Yugoslavia and a Gold prize^{[7]} at the 1968 International Mathematical Olympiad in Moscow.^{[8]} He read mathematics at Trinity College, Cambridge, graduating in 1971. After a year at Liverpool University, he joined GCHQ, and worked there until 1982.

From 1985 to 1989 Williamson worked at Nicolet Instruments in Madison, Wisconsin where he was the primary author on two digital hearing aid patents.^{[9]}^{[10]} After that, he moved to the IDA Center for Communications Research, La Jolla,^{[11]} where he worked for the rest of his career.

His contributions to the invention of public-key cryptography, together with Clifford Cocks and James Ellis, have been recognized by the IEEE Milestone Award #104^{[12]} in 2010 and by induction into the Cryptologic Hall of Honor in 2021.

## See also[edit]

## References[edit]

**^**"In Memory of Malcolm John Williamson". Retrieved 26 June 2016.**^**"Malcolm John Williamson 1950 - 2015".*The San Diego Union Tribune*. 18 October 2015. Retrieved 26 June 2016.**^**"Malcolm John Williamson 1950 - 2015".*The San Diego Union Tribune*. 18 October 2015. Retrieved 26 June 2016.- ^
^{a}^{b}Singh, Simon (1999).*The Code Book*. Doubleday. pp. 279–292. **^**A.Gardiner "The Mathematical Olympiad Handbook" Oxford University Press, 1997**^***The Science Teacher volume 11 number 1 (October 1967) pages 30 and 31*, 1967, retrieved 26 January 2009**^***New Science Teacher volume 12 number 2 (December 1968) pages 31–35*, 1968, retrieved 26 January 2009**^**Malcolm J. Williamson's results at International Mathematical Olympiad**^**US Patent 5091952 - Feedback suppression in digital signal processing hearing aids**^**US Patent 5027410 - Adaptive, programmable signal processing and filtering for hearing aids**^**Arratia, Richard; Liggett, Thomas; Williamson, Malcolm (2014), "Scale-free and power law distributions via fixed points and convergence of (thinning and conditioning) transformations",*Electronic Communications in Probability*,**19**(39): 1–10, arXiv:1306.3017, doi:10.1214/ECP.v19-2923, S2CID 15038587**^***Milestones:Invention of Public-key Cryptography, 1969 - 1975*, 2010, retrieved 4 February 2022

## External links[edit]

- Williamson's January 1974 internal GCHQ note "Non-Secret Encryption Using a Finite Field" (A couple of typos in this pdf: Extended Euclidean Algorithm modulus should be (p-1) instead of p.

Enc and Dec are performed using exponentiation; It should have been A^{k} instead of Ak; similar A^{(KI)} and A^{I} instead of AKI and AI, respectively.
)

- 1950 births
- 2015 deaths
- GCHQ cryptographers
- Public-key cryptographers
- Modern cryptographers
- People educated at Manchester Grammar School
- 20th-century British mathematicians
- 21st-century British mathematicians
- Alumni of Trinity College, Cambridge
- International Mathematical Olympiad participants
- GCHQ people
- British mathematician stubs