#18unit 1technology solutions
Encryption
Transforming data to protect its confidentiality.
Substitution and transposition ciphers
Using a substitution cipher 'letter plus two,' 'Hello' becomes 'JGNNQ.' Using a transposition cipher, 'Hello' can be written backwards as 'OLLEH.' These ancient techniques illustrate the basic idea of transforming plain text into cipher text using a key.
Modern encryption uses 128-, 256-, or 512-bit binary keys; a 512-bit key would take all the world's computers about 10 years to break by brute force.