Book Image

Cryptography Algorithms

By : Massimo Bertaccini
Book Image

Cryptography Algorithms

By: Massimo Bertaccini

Overview of this book

Cryptography Algorithms is designed to help you get up and running with modern cryptography algorithms. You'll not only explore old and modern security practices but also discover practical examples of implementing them effectively. The book starts with an overview of cryptography, exploring key concepts including popular classical symmetric and asymmetric algorithms, protocol standards, and more. You'll also cover everything from building crypto codes to breaking them. In addition to this, the book will help you to understand the difference between various types of digital signatures. As you advance, you will become well-versed with the new-age cryptography algorithms and protocols such as public and private key cryptography, zero-knowledge protocols, elliptic curves, quantum cryptography, and homomorphic encryption. Finally, you'll be able to apply the knowledge you've gained with the help of practical examples and use cases. By the end of this cryptography book, you will be well-versed with modern cryptography and be able to effectively apply it to security applications.
Table of Contents (15 chapters)
1
Section 1: A Brief History and Outline of Cryptography
3
Section 2: Classical Cryptography (Symmetric and Asymmetric Encryption)
7
Section 3: New Cryptography Algorithms and Protocols
12
Section 4: Homomorphic Encryption and the Crypto Search Engine

Quantum key distribution – BB84

Let's introduce BB84, the acronym that's Charles Bennett and Gilles Brassard developed in 1984 valid for QKD.

Now that we have learned about the properties of Q-Mechanics, we can use them to describe a technique for distributing bits (or better, quantum bits) through a quantum channel.

To describe what a quantum bit, also known as a qubit, is, we have to refer to the "quantum unit information" that's carried by qubits. Like traditional bits, (0) and (1), qubits are mathematical entities subject to calculation and operations.

We will use a bi-dimensional vectorial complex space of unitary length to define a qubit. So, we can say that a qubit is a unitary vector acting inside of a two-dimensional space. So far, we can think of a qubit as a polarized photon, similar to the entanglement experiment we looked at in the previous section. I have already introduced the notation to represent the qubits inside "bra...