Generate cryptographically secure random numbers in php

Question

PHP\'s rand() function doesn\'t give good random numbers. So I started to use mt_rand() which is said to give better results. But how good are thes

Answer 1

All joking aside, you're getting into a philosophical question of what is "random" or what is "best". Ideally you'd want your random numbers to have few patterns in them over the course of your procedure. Generally system time is used as the seed, but I've also used the previous random number as the seed, the previous random numberth ago as the seed. The problem is, with a powerful enough computer and full knowledge of the hardware running, and generator function, you would be able to predict the entire set of numbers generated. Thus if you had a powerful enough computer (some people put God into this category) that knew all possible variables and functions of the universe you would then be able to predict every event that happened or will happen. Most random number generators are fine on their own but if you know someone who can see the patterns, more likely they are like the guy in Beautiful Mind and you should get them checked into a clinic.

By popular demand :D