In our world, where the majority of transactions of money, goods, and information are executed over the Internet, the importance of encryption is becoming critical.

In this chapter, we will dive into encryption and hashing to understand the capabilities of and possible security threats that these technologies can bring to you and your infrastructure. After this, we will see how the public key infrastructure works so you can understand the various weak points it can hide. Then, we will look at how to set up httpd and nginx with certificates to secure OpenStack APIs.

Encryption is a part of human history. Since the Roman emperor Gaius Julius Cesar (100–44 BC), many people have tried to create secure encryptions. The first attempt to create a cryptography system that is considered safe today was made by Frank Miller (1842–1925), who proposed one-time pads to enhance Vigenere encryption. Those pads created with random characters were used...