This chapter covers:
- Key Exchanges and their security properties.
- The popular key exchange algorithms.
- How key exchanges are used in practice.
We are now entering the realm of public key cryptography with our very first asymmetric cryptographic primitive: the key exchange. Briefly, this primitive allows two peers to openly derive a shared secret. Keep on reading to learn more!
As I have hinted in the introduction of this book, there is much more math involved in asymmetric cryptography, and thus the next chapters are going to be a tad more difficult. Don’t get discouraged, as what you will learn in this chapter will be helpful to understand the following chapters.
To understand exactly what real-world problems public key cryptography aims to solve, we need to take a step back and return to the symmetric cryptographic primitive you learned in chapter 4: Authenticated Encryption. Remember, it allows you to hide messages between participants, as long as they share a symmetric key.