How does encryption work Gary explains Probably use encryption every single day in our lives What is it o Process of taking normal info turning it into a version that can t be read by other people o To do conversion need a key Once you have the key can decrypt o Tom Jericho character put it in the film Enigma Turns playing text msgs into gobbledygook Prob machine has 115Mil long on risers o Adv of having encrypted are enormous if you don t want a cyberthief to take info Art of secret writing o Most famous Julius Creaser Write secret msgs to Cicero so used Casesar cypher Great thing shifting alphabet get diff results Disadvantages spaces would appear in encrypted msgs lletter e appears most frequent in Engl lang Frequency analysis notice which one s the most frequent just line it up decrypt it To make it stronger use multiple encryption alphabets not just 1 Letter repeats encrypted but different letters o Visionnaire Used all 26 alphabets 16th century popular cypher 300 yrs beore it could be cracked Cracked by Charles Babbage Didn t publish his work broken by Frederick Kaczynski and V fell o The One Time Pad Below ABCD use random sequence of letters As long as the message itself Rather than doing a straight substitution use addition w mod 26 to produce another letter Recipient needs to have exactly the same pair of exactly the same random sequence on it in order to oierosgj dlz