From Sixteenth-Century Cryptography to the New Millennium — The Last 500 Years - Codes: The Guide to Secrecy from Ancient to Modern Times - page 97

2.5 The Postwar Era and the Future

We shall see that cryptography is more than a subject permitting mathemati-
cal formulation, for indeed it would not be an exaggeration to state that abstract
cryptography is identical with abstract mathematics.
Abraham Adrian Albert 2.15 ( 1905 - 1972 )

Host Feistel may be considered to be one of the early pioneers in the drive
to secure privacy for the public at large using cryptography. Born in Germany
in 1914, he emigrated to the United States in 1934, but would not obtain a U.S.
citizenship for another decade. In fact, in 1941, with Germany having declared
war on America, he was placed on a (sort of) house arrest, where his movements
were restricted to the Boston area where he lived. Yet, surprisingly, on January
31, 1944, the house arrest was lifted, he was granted U.S. citizenship, and the
very next day he was given security clearance that allowed him to work at the Air
Force Cambridge Research Center (AFCRC). 2.16 There he set up a cryptography
research group that developed some outstanding cryptographic algorithms. In
particular, they developed the MARK XII , which is widely used in American
aircraft. It is known that the NSA had an ambivalent attitude toward Feistel's
group. On the one hand, they exerted pressure to steer his work, while at the
same time they considered his group to be a threat. Consequently his group was
dissolved in the late 1950s. Then Feistel moved to MIT's Lincoln Laboratory,
followed by a move to MITRE Corporation, a spinoff of the MIT lab. When
he tried to form a cryptography group there, again NSA exerted pressure on
MITRE, so his efforts failed, and his group did not materialize.
A.A. Albert, a friend of Feistel, advised him to go to IBM, since they were
hiring the brightest scientists to do their own innovative work, a kind of think
tank. Feistel began work at their Watson Laboratory in Yorktown Heights, New
York. There he created a cryptosystem used in the IBM2984 banking system,
known today as the Alternative Encryption Technique , but then it was called
Lucifer . 2.17 This cryptosystem was the predecessor of the first commercially

2.15 Albert was born in Chicago, Illinois, on November 9, 1905. He studied under L.E. Dickson
attheUniversityofChicago, receivinghisPh.D.in1928. Hiselegantworkontheclassification
of division algebras (see Appendix A, page 484) earned him a National Research Council
Fellowship. This provided him with the opportunity to secure a postdoctoral position at
Princeton, after which he spent a couple of years at Columbia University, then returned
to Chicago in 1931. His topic, Structure of Algebras , published in 1939, remains a classic
today. The events of World War II induced Albert to take an interest in cryptography.
The above quote is taken from his lecture on mathematical aspects of cryptography at the
American Mathematical Society meeting held in Manhattan, Kansas, on November 22, 1941.
His numerous achievements would take several pages to describe. SuFce it to say he has had
a lasting influence. He died on June 6, 1972, in Chicago.
2.16 There is speculation that something may have been going on behind the scenes between
Feistel and the U.S. government (see Levy's excellent topic Crypto [151] for an account of
some of these possible scenarios as well as with other related cryptographic activities).
2.17 Years later, Feistel said that if it had not been for the Watergate scandal that rocked
Washington, the NSA would probably have shut down the Lucifer project, as they had so
many of his earlier efforts. In fact, in the early 1970s, patent secrecy orders were placed on
some of Feistel's inventions by the U.S. government.