This chapter introduces the basic building blocks of modern digital cryptography, describes what they can do for you, and explains how to compose them to produce useful and practical secure services.
If you are familiar with these basics, you can probably skip this chapter. Good general references in this area are [NetSec] and [Schneier]. This chapter and indeed this book do not generally get down to the details of bit-level formats or algorithms. That is, they do not provide enough information for you to implement the cryptographic algorithms mentioned. Nevertheless, this chapter should provide a foundation of knowledge about modern digital cryptography that will make later chapters more comprehensible.
Sections 2.1, 2.2 and 2.3 generally discuss "symmetric" functions where the originator and receiver compute the same quantity or use the same secret key. Sections 2.4, 2.5 and 2.6 focus on "asymmetric" functions involving a public-private key pair. The remaining sections (2.7 2.11) discuss a variety of other important aspects of basic digital cryptography.