How to generate a symmetric encryption key
Generating an encryption key for symmetric encryption is surprisingly easy. You just request the needed amount of random bytes from your cryptographically secure random generator!
Which random generator is considered cryptographically secure? It is a random generator that generates bytes that are extremely hard to predict. The unpredictability of generated random bytes is accomplished by using the entropy caused by unpredictable events from the outside world. Often, cryptographically secure random generators use the entropy caused by the unpredictable timing of the input from a keyboard and mouse. If the keyboard and mouse are unavailable, for example, when an application is running in a container, then another source of entropy can be used, such as microfluctuations in the CPU speed. Another common entropy source is a ring oscillator that can be included in the CPU or another chip.
What is the correct amount of random bytes? It is the...
