# Scytale

Scytale

:"This article is about the encryption device; for the Dune character, see Scytale (Dune)." In cryptography, a scytale (/sɪtəli/ rhymes with Italy, and also transliterated as skytale, Greek "σκυτάλη", a baton) is a tool used to perform a transposition cipher, consisting of a cylinder with a strip of leather 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.

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 &mdash; 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.

Encrypting

Suppose the rod allows one to write 4 letters around in a circle and 5 letters down the side of it.The plaintext could be: "Help me I am under attack"

To encrypt one simply writes across the leather...

_____________________________________________________________
| | | | |
| H | E | L | P | M |
__| E | I | A | M | U |__
N | D | E | R | A |
T | T | A | C | K |
| | | | |
_____________________________________________________________

so the ciphertext becomes, "HENTEIDTLAEAPMRCMUAK" after unwinding.

Decrypting

To decrypt all one must do is wrap the leather strip around the rod and read across. The ciphertext is: "HENTEIDTLAEAPMRCMUAK"Every fifth letter will appear on the same line so the plaintext becomes HELPM...return to the beginning once the end is reached ...EIAMUNDERATTACKInsert spaces and the plaintext is revealed: "Help me I am under attack"

History

From indirect evidence, the scytale was first mentioned by the Greek poet Archilochus who lived in the 7th century BC. Other Greek and Roman writers during the following centuries also mentioned it, but it was not until Apollonius of Rhodes (middle of the 3rd century BC) that a clear indication of its use as a cryptographic device appeared. A description of how it operated is not known from before Plutarch (50-120 AD):

:"The dispatch-scroll is of the following character. When the ephors send out an admiral or a general, they make two round pieces of wood exactly alike in length and thickness, so that each corresponds to the other in its dimensions, and keep one themselves, while they give the other to their envoy. These pieces of wood they call scytalae. Whenever, then, they wish to send some secret and important message, they make a scroll of parchment long and narrow, like a leathern strap, and wind it round their scytale, leaving no vacant space thereon, but covering its surface all round with the parchment. After doing this, they write what they wish on the parchment, just as it lies wrapped about the scytale; and when they have written their message, they take the parchment off and send it, without the piece of wood, to the commander. He, when he has received it, cannot otherwise get any meaning out of it,--since the letters have no connection, but are disarranged,--unless he takes his own scytale and winds the strip of parchment about it, so that, when its spiral course is restored perfectly, and that which follows is joined to that which precedes, he reads around the staff, and so discovers the continuity of the message. And the parchment, like the staff, is called scytalae, as the thing measured bears the name of the measure."
&mdash;Plutarch, "Lives" (Lysander 19), ed. Bernadotte Perrin.

Due to difficulties in reconciling the description of Plutarch with the earlier accounts, and circumstantial evidence such as the cryptographic weakness of the device, several authors have suggested that the scytale was used for conveying messages in plaintext, and that Plutarch's description is mythological. [Kelly.]

References

Notes

General references

*Thomas Kelly, The myth of the skytale, "Cryptologia", July 1998, pp. 244&ndash;260.
*" [http://bcs.fltr.ucl.ac.be/FE/07/CRYPT/Intro.html Secret Language in Graeco-Roman antiquity] ". Thesis by Brigitte Collard that includes quotations of many ancient references to the scytale. (In French)

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### Look at other dictionaries:

• Scytale — Scytale. Pour les articles homonymes, voir Scytale (Dune). Chez les Spartiates, la scytale, également connue sous le nom de bâton de Plutarque, était un bâton de bois utilisé pour lire ou écrire une …   Wikipédia en Français

• scytale — ⇒SCYTALE, subst. fém. ANTIQ. GR. Bâton sur lequel on enroulait en spirale une lanière de parchemin sur laquelle on écrivait, de sorte qu une fois la lanière déroulée à nouveau, le texte ne pouvait être lu que par une personne possédant un bâton… …   Encyclopédie Universelle

• scytale — 1. (si ta l ) s. f. Terme d antiquité grecque. Sorte de chiffre dont se servaient les Lacédémoniens pour écrire des lettres mystérieuses, et qui consistait en ceci : on prenait deux rouleaux de bois de grosseur égale, dont les deux correspondants …   Dictionnaire de la Langue Française d'Émile Littré

• Scytale — es un personaje de la saga de novelas de ciencia ficción Dune, de Frank Herbert. Aparece en El Mesías de Dune, Herejes de Dune y Casa Capitular Dune. En El Mesías de Dune es un danzarín rostro tleilaxu implicado en las conjuras contra el… …   Wikipedia Español

• Scytăle [1] — Scytăle (gr. Ant.), s. Skytale …   Pierer's Universal-Lexikon

• Scytăle [2] — Scytăle, 1) nach Latreille u. Dandin Gattung aus der Schlangenfamilie Vipern, kenntlich daran, daß Bauch u. Schwanz ungetheilte Schilder haben, Kopf dick, stumpf, hinten verdickt; vorn mit kleinen Schildern, hinten mit rautenförmigen Schuppen… …   Pierer's Universal-Lexikon

• SCYTALE — I. SCYTALE Graece Σκυτάλη, genus Epistolae secretae,d Laconibus olim usitatae, de qua sic A. Gellius l. 17. c. 9. Lacedaemonii veteres, quum dissimulare et occultare liter as publice ad Imper atores suos missas volebant, ne si ab hostibus… …   Hofmann J. Lexicon universale

• scytale — ˈsid.əl(ˌ)ē noun ( s) Etymology: Latin scytale, scytala, scutula, from Greek skytalē staff, cylinder, message 1. : a method of cipher writing used especially by the Spartans in which a narrow strip of parchment was wound on a rod and the message… …   Useful english dictionary

• SCYTALE — s. f. T. d Antiq. grecque. Chiffre dont les Lacédémoniens se servaient pour écrire des lettres mystérieuses : il consistait en une bande étroite de parchemin sur laquelle on écrivait après l avoir roulée en spirale autour d un cylindre de bois ;… …   Dictionnaire de l'Academie Francaise, 7eme edition (1835)

• scytale — scyt·a·le …   English syllables