What are good sources of randomness?
Feeding cosmic background radiation through one-way functions (such as MD5) is one approach. Remember that the one-way function is used, in such a case, to adjust the statistical properties of the data, not as super-encryption – so a lower-quality one-way function such as DES or MD5 is acceptable, even though they might not be good enough to use for encryption in their own right, anymore. Using radioactive decay is another option! The randomness of radioactive decay is an open question depending on whose cosmology you believe, which is another reason that feeding samples of background radiation through another permutation generator such as a one-way hash is a good idea. See Internet RFC 1750 for more information on generating random numbers. Quality random numbers are a very important problem in cryptography. Not only must the number have the properties of a random number, it must be unpredictable. For example, the output of random() might appear to be statistically random, but is abso
