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:
“Our young people are diseased with the theological problems of original sin, origin of evil, predestination, and the like. These never presented a practical difficulty to any man,—never darkened across any man’s road, who did not go out of his way to seek them. These are the soul’s mumps, and measles, and whooping- coughs, and those who have not caught them cannot describe their health or prescribe a cure. A simple mind will not know these enemies.”
—Ralph Waldo Emerson (1803–1882)
“Hats have never at all been one of the vexing problems of my life, but, indifferent as I am, these render me speechless. I should think a well-taught and tasteful American milliner would go mad in England, and eventually hang herself with bolts of green and scarlet ribbon—the favorite colour combination in Liverpool.”
—Willa Cather (1876–1947)
“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)