Cryptography (from Ancient Greek κρυπτός “hidden” + γράφω “I write”), as a science of methods ensuring confidentiality, data integrity, authentication, and encryption, serves as one of the most crucial elements enabling modern cryptocurrencies and blockchains.
However, the cryptographic methods in use today are nothing but the result of an incredibly long history of development. After all, people have been using cryptography to transmit information securely since ancient times.
Ancient Roots of Cryptography
Cryptographic methods have been used since ancient times, with early civilizations using symbol substitution as the primary form of encryption. The earliest example of symbol substitution was found in the tomb of Khnumhotep II, an Egyptian nobleman who lived 3900 years ago. It was used to enhance the linguistic appeal of his name rather than to conceal information.
Around 3500 years ago, Mesopotamian scribes began using cryptography to protect confidential information, such as concealing the formula for pottery glaze on clay tablets.
Cryptography was widely used in later periods, including Ancient Greece, where messages were encrypted using parchment and cylinders.
Romans achieved advanced cryptography with a shift of letters by a certain number of places in the Latin alphabet for encryption and decryption.
Development in the Middle Ages and the Renaissance
In the Middle Ages, cryptography gained significant importance, with substitution ciphers like Caesar’s cipher being widely used.
However, cryptanalysis—the science of codebreaking—had already begun to develop, necessitating more complex cryptography. Around 800 CE, the Arab mathematician Al-Kindi introduced frequency analysis, making substitution ciphers vulnerable to decryption.
In response, in 1465, Leon Battista Alberti developed the polyalphabetic cipher, using two different alphabets for encoding, making frequency analysis ineffective. This significantly increased the security of encrypted information.
Additionally, during the Renaissance, new encoding methods emerged, including the biliteral cipher, invented by Sir Francis Bacon in 1623.
Achievements of the Last Centuries
Cryptography, as a science, continued to progress over the centuries. A major breakthrough in cryptography was described by Thomas Jefferson in the 1790s. His invention, known as the “Jefferson disk,” consisted of 36 letter rings on rotating wheels that could be used for complex encoding. This concept was so advanced that it served as the basis for American military cryptography up to World War II.
An excellent example of analog cryptography in World War II is the portable Enigma encryption machine. Similar to the wheel cipher, this device had rotating wheels for message encoding, making the message practically unreadable without another Enigma.
Cryptography in the Computer Era
The advent of computers led to significant progress in cryptography compared to earlier analog methods. Modern encryption is based on robust 128-bit mathematical encryption, surpassing the security of ancient and medieval ciphers. In the 1990s, computer scientists began developing quantum cryptography as a new form of encryption to further enhance security.
Cryptography has played a crucial role in the creation of cryptocurrencies. Technologies like hash functions, public-key cryptography, and digital signatures are used to protect data stored in blockchains and authenticate transactions. Cryptocurrencies, such as Bitcoin, use the Elliptic Curve Digital Signature Algorithm (ECDSA) to enhance security, ensuring that access to funds can only be obtained by an authorized user.
Cryptography has made significant progress over the last 4000 years and shows no signs of stopping. As long as there is a need to protect confidential information, cryptography will continue to evolve. Although cryptographic systems used in modern blockchains represent cutting-edge technologies, they are based on a rich historical tradition that traces its roots back to the history of humanity.
