Essential Computer Hardware

Data Encryption

Data encryption is a method of keeping data secure in storage or when transmitted, where the data is encoded using an encryption key, and can only be decrypted by a user with the correct key.

The un-encrypted data is called plaintext, and the encrypted data is called a ciphertext.

To demonstrate how encryption works, we’ll use a very simple technique called a Caesar cipher.

With Caesar ciphers, each letter in the plaintext is replaced by a letter a fixed number of positions down the alphabet.

So to encrypt the word BANANA, you would get FERERE

Another way to encrypt data is to use a Vernam cipher. With this scheme, each plaintext ...