Richard Treadwel Hallock (Passaic

Passaic, New Jersey

Passaic is a city in Passaic County, New Jersey, United States. As of the 2010 United States Census, the city had a total population of 69,781, maintaining its status as the 15th largest municipality in New Jersey with an increase of 1,920 residents from the 2000 Census population of 67,861...

, New Jersey

New Jersey

New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...

, 5 April 1906 - Chicago

Chicago

Chicago is the largest city in the US state of Illinois. With nearly 2.7 million residents, it is the most populous city in the Midwestern United States and the third most populous in the US, after New York City and Los Angeles...

, November 20, 1980) was an American

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 Assyriologist and Elam

Elam

Elam was an ancient civilization located in what is now southwest Iran. Elam was centered in the far west and the southwest of modern-day Iran, stretching from the lowlands of Khuzestan and Ilam Province, as well as a small part of southern Iraq...

itologist. He reached his Ph.D. degree in Assyriology at the University of Chicago

University of Chicago

The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...

 in 1935 , and was editorial secretary of the Chicago Assyrian Dictionary

Chicago Assyrian Dictionary

The Chicago Assyrian Dictionary or The Assyrian Dictionary of the Oriental Institute of the University of Chicago is a nine-decade project at the University of Chicago's Oriental Institute to compile a dictionary of the Akkadian language and its dialects, focusing on the New-Assyrian forms...

 (1955–1957). His major work is Persepolis Fortification Tablets (1969), the first edition and translation of the Persepolis Fortification Archive

Persepolis Fortification Archive

The Persepolis Fortification Archive and Persepolis Treasury Archive are two groups of clay administrative archives — sets of records physically stored together - found in Persepolis dating to the Persian Achaemenid Empire...

.

Hallock also played an instrumental role in the Venona project

Venona project

The VENONA project was a long-running secret collaboration of the United States and United Kingdom intelligence agencies involving cryptanalysis of messages sent by intelligence agencies of the Soviet Union, the majority during World War II...

. While working on Soviet "Trade" traffic (so named because these messages dealt with Soviet trade issues), Hallock discovered that the Soviets were reusing pages of some of the one-time pad

One-time pad

In cryptography, the one-time pad is a type of encryption, which has been proven to be impossible to crack if used correctly. Each bit or character from the plaintext is encrypted by a modular addition with a bit or character from a secret random key of the same length as the plaintext, resulting...

s they relied upon to encrypt their messages. Hallock and his colleagues (including Genevieve Feinstein, Cecil Phillips, Frank Lewis, Frank Wanat, and Lucille Campbell) went on to break into a significant amount of Trade traffic, recovering many one-time pad

One-time pad

In cryptography, the one-time pad is a type of encryption, which has been proven to be impossible to crack if used correctly. Each bit or character from the plaintext is encrypted by a modular addition with a bit or character from a secret random key of the same length as the plaintext, resulting...

additive key tables in the process.