Quantum Cryptography

Quantum Computing and Quantum Cryptography

What do they mean for traditional cryptography?

Tim Moses Director, Advanced Security Technology Robert Zuccherato Chief Cryptographer January 13, 2005 Version 1.1

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Quantum Computing and Quantum Cryptography

Table of Contents

1 Introduction ......................................................................................................................... 2 1.1 Classical Physics and Computation....................................................................... 2

2 Quantum Mechanics ........................................................................................................... 2 3 Quantum Cryptography...................................................................................................... 4 3.1 3.2 3.3 3.4 Random Processes .................................................................................................. 4 The Key Distribution Problem ................................................................................. 4 The Quantum Solution ............................................................................................. 4 Quantum vs. Public-Key Cryptography.................................................................. 6

4 Quantum Computing .......................................................................................................... 7 4.1 4.2 Realizing a Quantum Computer...