Problems
It is very easy to misconstruct hardware or software devices which attempt to generate random numbers. Also, most 'break' silently, often producing decreasingly random numbers as they degrade. A physical example might be the rapidly decreasing radioactivity of the smoke detectors mentioned earlier. Failure modes in such devices are plentiful and are complicated, slow, and hard to detect.
Because many entropy sources are often quite fragile, and fail silently, statistical tests on their output should be performed continuously. Many, but not all, such devices include some such tests into the software that reads the device.
Just as with other components of a cryptosystem, a software random number generator should be designed to resist certain attacks. Defending against these attacks is difficult. See: random number generator attack.
Read more about this topic: Hardware Random Number Generator
Famous quotes containing the word problems:
“One of the annoying things about believing in free will and individual responsibility is the difficulty of finding somebody to blame your problems on. And when you do find somebody, it’s remarkable how often his picture turns up on your driver’s license.”
—P.J. (Patrick Jake)
“The three great problems of this century, the degradation of man in the proletariat, the subjection of women through hunger, the atrophy of the child by darkness.”
—Victor Hugo (1802–1885)
“The truth of the thoughts that are here set forth seems to me unassailable and definitive. I therefore believe myself to have found, on all essential points, the final solution of the problems. And if I am not mistaken in this belief, then the second thing in which the value of this work consists is that it shows how little is achieved when these problems are solved.”
—Ludwig Wittgenstein (1889–1951)