Cryptography Apocalypse

3How Can Quantum Computing Break Today's Cryptography?

This chapter covers how quantum computing is likely capable of breaking most forms of traditional public key encryption. We begin by discussing cryptography basics, paying particular attention to how most of today's public key encryption schemes provide protection. Then you will build on your foundation from Chapter 2 and learn how quantum computers can break that protection and what cryptography is or isn't overly susceptible to quantum cracking.

Cryptography Basics

Cryptography is the science, study, and practice of securing and authenticating people, data, transactions, and other objects between authorized parties. It is done by using encryption, integrity checks, and algorithmic implementations. Cryptography allows confidentiality and integrity of data, communications, and participants to be maintained whenever desired between authorized, designated parties (or software or devices on their behalf). This section will cover digital encryption, authentication, and integrity hashing basics.

NOTE  The term subject will be used throughout this chapter. It is used to refer to any identity that can be tied to a cryptographic action. A subject can be a user, group, computer, device, service, daemon, company, publisher, or any other identity object.

Encryption

Encryption is a popular method for subjects to keep something secret. A single subject may want to keep something secret to itself, or the secret may be shared between ...