John R Pierce wrote: > the seed of a algorithm like /dev/urandom is not a single variable, its > a big array of variables. these have to be created with sufficiently > random external events to achieve a reasonable level of entropy, and if > you continue to generate pseudo-random-numbers from this when those > random external events aren't ongoing at a high enough rate relative to > your requirements for new random numbers, eventually the 'entropy' runs > out, and the sequence becomes increasingly predictable. According to Wikipedia "A random seed (or seed state, or just seed) is a number (or vector) used to initialize a pseudorandom number generator." It is impossible to measure the entropy of a single number, or vector. If you think it is, tell me how you measure it. -- Timothy Murphy e-mail: gayleard /at/ eircom.net School of Mathematics, Trinity College, Dublin 2, Ireland