Produced for ExpressVPN and originally uploaded to YouTube on November 8th, 2023.

From knitting patterns to quantum algorithms, cryptography has come a long way.

Join us as we journey through thousands of years of encryption.

Ancient times (7th century BC – 58 BC)

• Spartans used the scytale, a tool with a wrapped parchment, to encode and decode messages by writing on it and unwrapping it using a matching rod.
• Named after Julius Caesar, who used it for private communication, a substitution cipher replaced letters with others a fixed number of spaces away. Despite it being flawed, the Russian army used it in World War I.

Medieval times & The Renaissance (15th – 16th century)

• Alberti introduced the polyalphabetic cipher using rotating alphabetic discs for encoding and decoding messages.
• The Vigenère cipher by Blaise de Vigenère applied multiple Caesar ciphers with a keyword, improving message security.

Beginnings of Modern Cryptography (19th – early 20th century)

• The telegraph’s rise in the 19th century led to privacy concerns, prompting governments and telegraph companies to use ciphers and codes to counter interception.

Cryptography’s role in World Wars (1914-1945)

• Knitting became an espionage tool in World War I for signaling trains. In World War II knitting patterns were banned due to security concerns.
• The Enigma machine, a German-made WWII device, was decrypted by Alan Turing’s team, altering the war’s outcome and inspiring cryptographic advancements.

Digital age (1970s – 2010s)

• Diffie and Hellman’s public key cryptosystems revolutionized encryption, allowing secure message exchange without sharing secret keys.
• Network protocols like PPTP, L2TP, and IPsec were developed in response to the need for secure remote connections during the internet boom.
• SSL introduced user-friendly cryptographic protocols, paving the way for commercial VPNs like ExpressVPN.

Today’s encryption (2023 and beyond)

• AES became the foundation of modern encryption, ensuring secure communication and data protection with varying key lengths.
• Messaging apps like WhatsApp implemented end-to-end encryption, ensuring high confidentiality for sender and recipient.
• Blockchain technology secures transactions and enhances data integrity beyond finance, revolutionizing industries.
• Quantum cryptography uses quantum principles to secure data transmission, generating unbreakable encryption keys with quantum key distribution systems.
• Engineers are developing post-quantum cryptographic algorithms, including those at ExpressVPN, to protect against quantum-based threats.

And there you have it, the history of encryption in a nutshell. How do you think encryption will evolve in the future? Let us know in the comments below!

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