Network Security: Private Communications in a Public World, 3rd Edition

6 First-Generation Public Key Algorithms

6.1 Introduction

This chapter describes the most common public key algorithms that have been deployed as of 2022 and that will probably remain the most common public key algorithms in use for several years. As we will show in Chapter 7 Quantum Computing, if someone could build a quantum computer of sufficient size, the algorithms in this chapter would no longer be secure. The world will soon be converting to different public key algorithms (see Chapter 8 Post-Quantum Cryptography). But the current algorithms, the focus of this chapter, are widely deployed and fascinating to understand.

Public key algorithms are a motley crew. All the hash algorithms do the same thing—they take a message and perform an ...