Chapter 5. Symmetric Encryption

This chapter discusses the basics of symmetric encryption algorithms. Message integrity checking and hash functions are covered in Chapter 6. The use of cryptography on a network is discussed in Chapter 9.

Many of the recipes in this chapter are too low-level for general-purpose use. We recommend that you first try to find what you need in Chapter 9 before resorting to building solutions yourself using the recipes in this chapter. If you do use these recipes, please be careful, read all of our warnings, and do consider using the higher-level constructs we suggest.