1. A method of detecting a change to a pool of random numbers, the method comprising: applying an operation to each element in the pool to generate a first set of values, wherein each value in the first set of values relates to an association of a first element in the pool with a second element in the pool; generating a first cyclic graph based at least in part on the first set of values; determining a first number of steps required to identify a first cycle in the first cyclic graph from a first starting point in the first cyclic graph; after an event, applying the operation to each element in the pool to generate a second set of values; generating a second cyclic graph based at least in part on the second set of values; determining a second number of steps required to identify a second cycle in the second cyclic graph from a second starting point in the second cyclic graph associated with the first starting point; and generating a flag if the first number of steps and the second number of steps differ.