Cryptography, or the practice of encrypting or disguising private messages/information, has deep roots. So deep in fact that they trace all the way back to 1900 BC. It’s easy to think that the ways in which your computer’s information is protected aren’t that big of a deal, but it’s been a long journey getting the world to this point. While a number of our day-to-day computer-related activities touch cryptography in one way or another, we seldom stop to think about just how it is that our information is protected. We take for granted the great technological advancements that history has brought cryptography, forgetting that we used to disguise messages via quill and ink. Let’s take a few minutes to explore the history of message concealment and cryptography, so we can appreciate how far we’ve come.
The most basic manifestation of message concealment came in the form of mere pen on paper. Since most individuals could not read, even perfectly legible transcriptions were nothing more than jumbles of graphemes.
1900 BC: The earliest evidence of cryptography comes from ciphertext carved on a stone in Egypt. There is speculation, however, that this rearrangement of letters might have been more for the amusement of the literate than for concealment. In afct, ew tslil od htsi otayd.
1500 BC: Information written on clay slabs in Mesopotamia served the purpose of protecting valuable information, be it commercially valuable or sensitive. For example, one slab was found to contain a craftsman’s secret recipe for pottery glaze.
400 BC: The Karma Sutra recommends cryptography as a viable way for lovers to keep the contents of intercepted messages secret.
As with any developing practice, cryptography saw many new advancements. By the middle ages, improvements and innovations were abound.
800 AD: A frequency analysis technique was developed by Al-Kindi, an Arab mathematician. The system observed the frequency of individual characters in a message and was used for breaking monoalphabetic ciphers.
1467 AD: Leon Battista Alberti explained polyalphabetic ciphers or codes, earning him the title of “Father of Western Cryptology.”
1400s – 1600s: During the European Renaissance, citizens of Italian states were hard at work on cryptographic practices. The primary reasons were to communicate about various political and religious issues.
1586: The Babington plot, which aimed at the assassination of Queen Elizabeth I, was unraveled by means of cryptanalysis. Mary, Queen of Scots, was incriminated in the plan to overtake the throne when her secret messages were deciphered and she was subsequently executed.
1800 to WWI
Things were quiet in the world of cryptography for many years. However, by the 1800s and into World War 1, the practice surged, becoming both amusing and highly useful. Key events included:
1840s: Noted poet Edgar Allan Poe publicly boasted his ability to solve ciphers, going so far as to challenge readers of Alexander’s Weekly (Express) Messenger to submit messages for him to solve, most of which he did. Poe later wrote an essay on cryptography, which aided British WWI efforts against the Germans.
Read more about Poe’s work in cryptography.
1853 – 1856: Charles Babbage aided British Crimean War efforts with his breaking of polyalphabetic ciphers, including Vigenère’s autokey cipher and the weaker Vigenère cipher.
1917: Gilbert Vernam devised a teleprinter cipher, which used a prepared key on paper tape to be combined with regular text to disguise messages. From here, various cipher machines would be used.
WWII – 1950s
By the time World War II came about, use of both mechanical and electromechanical cipher machines were commonplace. During this time period, major advances in both cipher design and cryptanalysis were made.
1920s – 1930s: The Enigma rotor machine, a cipher machine used by the German Army, was invented by Arthur Scherbius. Poland Cipher Bureau’s mathematician, Marian Rejewski, cracked its codes in 1932, unbeknownst to the Germans. His accomplishment enabled Poland, France and Britain to track the Germans. Later models made by both the British (Typex machine) and the US (SIGABA machine) would improve upon the concepts of Enigma.
1942: The Japanese Navy cryptography system, JN-25, was broken by the US Navy. This enabled the US to interpret Japanese messages and claim victory in the Battle of Midway.
1943 – 1944: Max Newman and engineer Tommy Flowers designed the world’s first programmable digital electronic computer, Colossus, to help with Britain’s cryptanalysis.
1950s: The VIC cipher, used by Soviet spy Reino Häyhänen, the most complex pen-and-paper cipher, was discovered. It had remained unbroken during the war.
Modern Advancements and Use
With the evolution of the computer, algorithms and ciphers have gotten more complex. As cryptography had traditionally been used by the military and government, its emergence in public use was, at the time, surprising.
1975: The US Federal Register established the Data Encryption Standard (DES), a data encryption algorithm, for secure electronic communication in banks and financial organizations. By 1977 it would be altered and known as the Federal Information Processing Standard (FIPS).
1976: Whitfield Diffie and Martin Hellman introduced a new key distribution system, the Diffie-Hellman key exchange. This would eventually lead to the public key system, which uses only 2 keys per user. One key is private and used for message decryption and the other is public and used for encryption, eliminating the need for a secure channel.
1991: PGP (Pretty Good Privacy), a top-notch cryptography system, was released to the public by Phil Zimmerman. Shortly after the US release, the system was released worldwide with much government criticism.
2001: The DES and the similar FIPS were officially replaced by the Advanced Encryption Standard (AES). The DES and other incarnations (i.e. Triple DES) are still used by some, however.
Message and data encryption continue to evolve, and – as you have seen – have a long history. We’ve only scratched the surface of cryptography with this article; but if you want to learn more, there are plenty of great resources for doing so: