![pseudo random generator algorithm pseudo random generator algorithm](https://i.stack.imgur.com/Qsm1t.jpg)
For example, your computer might notice that you pressed a key at exactly 0.23423523 seconds after 2 p.m. An attacker wouldn’t be able to predict when radioactive decay would occur, so they wouldn’t know the random value.įor a more day-to-day example, the computer could rely on atmospheric noise or simply use the exact time you press keys on your keyboard as a source of unpredictable data, or entropy. According to quantum theory, there’s no way to know for sure when radioactive decay will occur, so this is essentially “pure randomness” from the universe. For example, the computer could measure the radioactive decay of an atom. To generate a “true” random number, the computer measures some type of physical phenomenon that takes place outside of the computer. We generally group the random numbers computers generate into two types, depending on how they’re generated: “True” random numbers and pseudo-random numbers. If it’s just a piece of computer code, isn’t it possible the numbers the computer generates could be predictable? You may be wondering how a computer can actually generate a random number. These random numbers are essential for secure encryption, whether you’re encrypting your own files or just using an HTTPS website on the Internet. We want to generate these numbers in a very unpredictable way so attackers can’t guess them. We can’t just use the same numbers over and over. Cryptography requires numbers that attackers can’t guess.