Frank Rubin

Frank Rubin – short bio

I have a BS and MS in Mathematics and a PhD in Computer Science. I worked for 28 years at IBM

in the Design Automation field, meaning that I designed and wrote specialized software which

IBM engineers used to design computers and circuits.

I am the owner of Master Software Corp. which produces cryptographic software. I have been issued

four U.S. patents on cryptographic methods.

I taught a two-semester course on cryptography at Marist College CLS (Continuing Life Studies)

as well as lecturing on various topics in mathematics and science.

I have about 50 papers published in refereed journals on cryptography, computer circuits, graph theory

and pure mathematics, plus several books (user's manuals and project specifications) published

internally at IBM.

In cryptography I am best known for solving the Jefferson Cypher Wheel (Computer Methods for

Decrypting Multiplex Ciphers, Cryptologia 2 (Apr. 1978), pp 152-160) and for breaking the Pless

Cipher which uses 8 interlaced linear feedback shift registers (Decrypting a Stream Cipher Based on

J-K Flip-flops, IEEE Trans. on Computers 28 (July 1979), pp 483-487. Reprinted in Cryptologia

5 (Jan. 1981), pp 51-57).

In Computer Science I am best known for arithmetic coding, now one of the standard methods for text

compression (Arithmetic Stream Coding Using Fixed Precision Registers, IEEE Trans. on Info. Theory

25 (Nov. 1979), pp 672-675), and for my algorithm for finding Hamilton paths (A Search Procedure

for Hamilton Paths and Circuits, J. ACM 21 (Oct. 1974), pp 576-580).

In pure mathematics I am probably best known for introducing the concept of a finite-state

recognizer to measure theory (The Measure of Recognizable Sets of Real Numbers, Amer.

Math. Monthly 83 (May 1976), pp 348-349).

I am a former editor of Cryptologia, and of Journal of Recreational Mathematics. I have 3 published

books of Sudoku puzzles and two self-published books of SumSum puzzles.

I am the author of more than 3500 puzzles published in The Cryptogram, Technology Review, Journal

of Recreational Mathematics, etc. I am the only person ever honored by having a special issue of JRM

dedicated entirely to his own puzzles. My website www.contestcen.com also has hundreds of these

puzzles. I publish more than 50 new interactive puzzles each week on www.sumsumpuzzle.com. My

serious cryptographic work is on my third website www.mastersoftware.biz.

I am active in my local ACM chapter, and have presented lectures on cryptography and other subjects.

From 1980 to 2009 I ran a puzzle contest company, The Contest Center, which held about 1650 puzzle

contests, published two newsletters, and paid some $985,000 in cash prizes.