Symmetric Key Cryptography: The Keyword Cipher

This is the second in a series about cryptography; an extremely important aspect of computer science and cyber security. It covers a substitution cipher called the keyword cipher, also known as the Vigenère cipher. It explains how a keyword, or key phrase, can be used to effectively generate several different substitution keys for the same plain text message. The video includes a few examples you can try to encrypt and decrypt yourself using different encryption keys. It also describes how cipher text can be transformed again, with a second keyword, to improve the strength of encryption.

[arturovalerobotella]

Hello, thanks for the video, but in 3:59 there is an error, you must remark 'E' en the lower circle that corresponds with 'Y in the upper cicle', how do you really write in the code text, you remark 'E' in upper with 'K' lower. Really thank you very much for your work is great!!!