A scytale (also called skytale) is a tool used to perform a
transposition cipher, consisting of a cylinder with a strip of paper
wound around it on which is written a message. The ancient Greeks, and
the Spartans in particular, are said to have used this cipher to
communicate during military campaigns.i
The recipient uses a rod of the same diameter on which he wraps the
paper to read the message. It has the advantage of being fast and not
prone to mistakes — a necessary property when on the battlefield. It
can, however, be easily broken. Since the strip of paper hints
strongly at the method, the ciphertext would have to be transferred to
something less suggestive, somewhat reducing the advantage noted.