Most engineers will be able to get through an entire career without having to think about the mathematical realities that underlie the principles of randomness and entropy—even though many use or design applications that rely on them to ensure the security of their interactions. For the most part, engineers simply take the vendor’s specifications at face value when incorporating the cryptography hardware (and the code that supports it) into designs. Unfortunately, some recent discoveries about the more subtle and not-well-documented characteristics of random noise sources have shown that you may not be getting all the security you paid for.