Career
During World World War II he worked for the Army Signal Corps and at Arlington Hall, headquarters of the United States Army"s Signals Intelligence Service (SIS) cryptography, under William and Elizabeth Friedman on breaking the German and Japanese codes. Dumey is also considered by some the inventor of hashing. He published the first hashing paper in 1956.
Later, as a consultant, he co-invented the postal sorter and wrote the code that is used on the front of all United States Postal Service envelopes and packages in order to facilitate delivery.
In addition, he developed the first system to charge theater tickets to a cr card over the phone for the League of New York Theaters. The "Dumey microsecond" is a term of art in the intelligence community of the United States where Dumey spent much of his career.
The Dumey Microsecond was a crucial event that Arnold claimed was common to all projects: lieutenant is that microsecond during which you can impact the flow of, or design of, a project Before this microsecond, it is too early.
After, it is too late to have an impact.
Through the early 1970s, Dumey, then working for the Institute for Defense Analysis in Princeton, was the longest-serving member in the history of the National Security Agency scientific advisory board.