Skytale
The Skytale ( ancient Greek σκυτάλη skytálē , “stick”, “stick”) is the oldest known military encryption method . More than 2500 years ago, secret messages were not transmitted in plain text by the Spartans . A (wooden) stick with a certain diameter (Skytale) was used for encryption .
Technical details
To compose a message, the sender wrapped a piece of parchment or a strip of leather in a spiral around the Skytale, wrote the message on the tape along the length of the stick, and then unwrapped it. The tape without the wand is delivered to the recipient. If the tape falls into the wrong hands, the message cannot be read because the letters appear to be randomly arranged on the tape. The correct recipient of the tape could read the message with an identical Skytale (a rod of the same diameter). The diameter of the rod is therefore the secret key in this encryption process.
The Skytale belongs to the transposition method .
Historical background
In his biography of the Spartan military leader Pausanias , Cornelius Nepos (Paus. 3, 4) reports such a coded message: Pausanias was suspected of planning an overthrow when he was with the army in Asia Minor , and was sent via Skytale encrypted message ordered back home. It is believed that in his capacity as guardian of the underage King Pleistarchus he had access to the Skytale, which he needed for deciphering.
Another example comes from the Greek historian Plutarch . In his biography of the Spartan general Lysander he describes how he was able to thwart an attack by the Persians during the Peloponnesian War ( 431 BC - 404 BC ) . The corresponding advance warning was given in the form of a message that was encrypted with a Skytale.
Due to its easy handling and the high level of security (for the time) that it offered, the Skytale was also widespread in the Persian Empire. How advanced this system of interchanging letters, i.e. transposition, is is proven by the fact that transposition reappeared for the first time in the Middle Ages after the fall of classical culture .
literature
- Friedrich L. Bauer : Deciphered Secrets. Methods and maxims of cryptology. 2nd expanded edition. Springer, Berlin et al. 1997, ISBN 3-540-62632-8 , p. 102.
