• Aucun résultat trouvé

The Caesar cipher

N/A
N/A
Info
Télécharger
Protected

Academic year: 2022

Partager "The Caesar cipher"

Copied!
2
0
0

Chargement.... (Voir le texte intégral maintenant)

Texte intégral

(1)

Season 03 • Episode 09 • The Caesar cipher

0

The Caesar cipher

Season 03

Episode 09 Time frame 1 period

Prerequisites :

Coneptsofryptography.

Objectives :

•

Disover asimple enryption algorithm.

•

Pratise the enryption and deryption proesses.

Materials :

•

Beamer about the Caesaripher.

•

Lesson about the Caesaripher.

1 – How the Caesar cipher works 15 mins

The teaher explains, with a beamer,the history of the Caesar ipherand how it works.

2 – Coding and decoding a short message 20 mins

Eahstudentenodesasimplequestionthathe willsendtoanotherstudent,whowillde-

ode thequestionusingthekeyindiatedbythesender, andthensendbak anenrypted

answer.

3 – Breaking the code 20 mins

(2)

The Caesar cipher

Season 03 Episode 09 Document Lesson

Aording to Suetonius, a historian in the Roman Empire, Julius Caesar used a simple

ode topreserve the serey of some messages.

If he had anything ondential to say, he wrote it in ipher, that is, by so

hanging the order of the letters of the alphabet, that not a word ould be

made out. If anyone wishes to deipher these, and get at their meaning, he

mustsubstitutethefourthletterofthealphabet,namelyD,forA,andsowith

the others.

Anyenryptiontehniqueinwhiheahletterintheplaintextisreplaedbyalettersome

xed number of positionsdown the alphabet has beome known asa Caesar ipher.

An example

v e n i v i d i v i i

Y H Q L Y L G L Y L F L

The implementation chain of a cipher

Sender Reeiver

This isplain

text, that

anyone ould

read if it

weresentwi-

thout being

enoded.

This isplain

text, that

anyone ould

read if it

weresentwi-

thout being

enoded.

Plaintext Plaintext

Wklv lv hq

hqfubswhg

whaw

xquhdgdeoh

zlwkrxw

iluvw ehlqj

ghfubswhg.

Algorithm Ciphertext Algorithm

Références

Télécharger maintenant ( PDF - 2 Page - 106.94 KB )

Documents relatifs

Is It Possible to Preserve Privacy in the Age of AI?

Previous research work has developed tools that provide users with more effective notice and choice [9, 18, 19, 31]. With increasing concerns about privacy because of AI, some

Du détournement au délire interprétatif : les figures de l’excès dans Julius Caesar de Shakespeare

Cassius veut inverser les rôles et mettre le loup (César) à la place de la chèvre (les Romains), appelés des moutons par Shakespeare pour faire écho au proverbe biblique

A simple API to the KnowledgeStore

In principle, we can combine the results of multiple SPARQL or CRUD queries inside the API, to provide results which could not be returned by a single SPARQL query.. During the Hack

The Empire in French History Teaching. From a Promise to a Burden

Until the beginning of the wars of independence, the history of the empire (involving conquest, exploitation, relations between the empire and metropolitan France) was

Digital restoration of a marble head of Julius Caesar from Noviomagus (Nijmegen)

Here we consider the bust that had been used by d’Hollosy, and make on it a digital reconstruction using the face of Tusculum bust (Figure 1, on the left)... Figure 1: The two

Julius Caesar in a 3D rendering from a 2D picture

In particular, I told that this approach could be interesting for some Roman marble busts, two of which are well-known portraits of Julius Caesar (Tusculum and Farnese [7]), and

Episode 09 – The Caesar cipher European section – Season 3

confidential to say, he wrote it in cipher, that is, by so changing the order of the letters of the alphabet, that not a word could be made out.. If anyone wishes to decipher these,

Jules César (Caius Julius Caesar)

César se retrouve véritablement maître du monde connu alors, il fait l’objet d’un véritable culte, lors de la réforme du calendrier, le mois de sa naissance sera nommé "