Encryption

Serious Security: What 2000 years of cryptography can teach us

These days, a lot of your data gets encrypted when you save it to disk or send it over the internet.

The data gets decrypted again when you read it back in or after it’s received at the other end.

For that, you need some sort of cryptographic algorithm – what’s known in the jargon as a symmetric cipher or secret-key encryption.

Symmetric ciphers use the digital equivalent of a key, typically a string of characters, to lock and unlock the data.

In this article, we’ll take a journey through the history of symmetric ciphers during the pen-and-paper era, before mechanical and electronic encryption devices came onto the scene.

From Julius Caesar in the first century BC to Joseph Mauborgne at the end of the second millennium AD, we’ll look at:

• How each generation of algorithms worked.
• Why they fell by the wayside.
• What was better – or not! – about what came next.

The good news is that you won’t need to wade through any advanced mathematics to appreciate this fascinating story…