**Are you an EPFL student looking for a semester project?**

Work with us on data science and visualisation projects, and deploy your project as an app on top of GraphSearch.

Lecture# Information Encoding: Compression, Error Correction, Cryptography

Description

This lecture covers the theory of information, focusing on compression to make messages shorter, error correction to protect messages, and cryptography to make messages unreadable by third parties. A game interface simulates an agent learning to secure and compress data through interactive mini-games. The session aims to introduce players to cryptography and data compression in a simple and mysterious way. The gameplay involves understanding concepts like the Caesar cipher and applying them in interactive challenges. The lecture also explores the study of infectious phenomena, applying the SIR model to COVID-19, and the mechanics of a strategy game related to epidemiology.

Login to watch the video

Official source

This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.

In course

Instructor

Related concepts (88)

HUM-380: Video games and gamification

Ce cours propose d'acquérir des compétences en étude du jeu vidéo et en game design, tout en invitant les étudiant.e.s à mettre leurs connaissances au service d'un projet collectif de gamification d'u

In cryptography, a Caesar cipher, also known as Caesar's cipher, the shift cipher, Caesar's code, or Caesar shift, is one of the simplest and most widely known encryption techniques. It is a type of substitution cipher in which each letter in the plaintext is replaced by a letter some fixed number of positions down the alphabet. For example, with a left shift of 3, would be replaced by , would become , and so on. The method is named after Julius Caesar, who used it in his private correspondence.

The Vigenère cipher (viʒnɛːʁ) is a method of encrypting alphabetic text where each letter of the plaintext is encoded with a different Caesar cipher, whose increment is determined by the corresponding letter of another text, the key. For example, if the plaintext is attacking tonight and the key is OCULORHINOLARINGOLOGY, then the first letter a of the plaintext is shifted by 14 positions in the alphabet (because the first letter O of the key is the 14th letter of the alphabet, counting from 0), yielding o; the second letter t is shifted by 2 (because the second letter C of the key means 2) yielding v; the third letter t is shifted by 20 (U) yielding n, with wrap-around; and so on; yielding the message ovnlqbpvt eoeqtnh.

In cryptography, a cipher (or cypher) is an algorithm for performing encryption or decryption—a series of well-defined steps that can be followed as a procedure. An alternative, less common term is encipherment. To encipher or encode is to convert information into cipher or code. In common parlance, "cipher" is synonymous with "code", as they are both a set of steps that encrypt a message; however, the concepts are distinct in cryptography, especially classical cryptography.

The Alberti Cipher, created in 1467 by Italian architect Leon Battista Alberti, was one of the first polyalphabetic ciphers. In the opening pages of his treatise De componendis cifris he explained how his conversation with the papal secretary Leonardo Dati about a recently developed movable type printing press led to the development of his cipher wheel. Alberti's cipher disk embodies the first example of polyalphabetic substitution with mixed alphabets and variable periods This device, called Formula, was made up of two concentric disks, attached by a common pin, which could rotate one with respect to the other.

In cryptography, a classical cipher is a type of cipher that was used historically but for the most part, has fallen into disuse. In contrast to modern cryptographic algorithms, most classical ciphers can be practically computed and solved by hand. However, they are also usually very simple to break with modern technology. The term includes the simple systems used since Greek and Roman times, the elaborate Renaissance ciphers, World War II cryptography such as the Enigma machine and beyond.