Black Chamber
The Black Chamber, officially the Cable and Telegraph Section and also known as the Cipher Bureau, was the first peacetime cryptanalytic organization in the United States, operating from 1917 to 1929. It was a forerunner of the National Security Agency (NSA).
For the postal monitoring office, see Cabinet noir. For the song by Blind Guardian, see Somewhere Far Beyond.Legacy[edit]
In 1931, Yardley, out of a job and desperate for an income during the Great Depression, wrote a book about the Cipher Bureau, titled The American Black Chamber. The term "Black Chamber" predates Yardley's use of it in the title of his book.
During World War II, the Signal Intelligence Service (SIS) was created to intercept and decipher the communications of the Axis powers. When the war ended, the SIS was reorganized as the Army Security Agency (ASA). On May 20, 1949, all cryptologic activities were centralized under a national organization called the Armed Forces Security Agency (AFSA), a division of the Department of Defense that, after issues relating to poor interagency communication and coordination, was reformed on November 4, 1952 into the National Security Agency (NSA).