Greetings, traveler; you’ve come a long way. While this is the last chapter, it’s all about the journey, not the end. You’re now equipped with the gear and skills required to step into the real world of cryptography. What’s left is for you to apply what you’ve learned.
Before parting ways, I’d like to give you a few hints and tools that’ll be useful for what follows. The quests you’ll face often follow the same pattern: it starts with a challenge, launching you on a pursuit for an existing cryptographic primitive or protocol. From there, you’ll look for a standard and a good implementation, and then you’ll make use of it in the best way you can. That’s if everything goes according to plan. . . .
You’re facing unencrypted traffic, or a number of servers that need to authenticate one another, or some secrets that need to be stored without becoming single points of failure. What do you do?