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1: One-Time Pad and Kerckhoffs' Principle

Last updated

Sep 22, 2022
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- 0.8: Exercise
- 1.1: What Is [Not] Cryptography?

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You can’t learn about cryptography without meeting Alice, Bob, and Eve. This chapter is about the classic problem of private communication, in which Alice has a message that she wants to convey to Bob, while also keeping the contents of the message hidden from an eavesdropper ${ }^{1}$ Eve. You’ll soon learn that there is more to cryptography than just private communication, but it is the logical place to start.

${ }^{1}$ "Eavesdropper" refers to someone who secretly listens in on a conversation between others. The term originated as a reference to someone who literally hung from the eaves of a building in order to hear conversations happening inside.

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