http://www.perlmonks.org?node_id=175805


in reply to Re: is rand() random
in thread is rand() random

Actually HotBits is not a generator that uses radioactive decay as a seed, it uses the decay to actually generate bits (actually it uses pairs of timing intervals between consecutive decay events to generate either 0 or 1 bits depending on whether the first or second interval was longer). The process is slow, about 30 random bytes generated per second, and requests for HotBits (up to 2k bytes at a time) are served from an inventory of about 2 million bits that is continually topped up in the background. Of course, your primary request is processed by a Perl CGI program that fetches your bits for you.