Fortuna is a family of cryptographically secure PRNGs; devised by Bruce Schneier and Niels Ferguson, who published it in 2003.

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Why are Fortuna entropy pools reset after a reseed?

I've implemented LibTomCrypt's version of fortuna and am wondering about the pool resetting after a reseed. In fortuna.c in libtomcrypt we have the following (which is that part that adds the entropy ...
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Why does Fortuna RNG use double SHA-256?

In the paper for Fortuna the authors say that you can use any good digest algorithm (obviously as long as its output is 256 bit) and then they recommend double SHA-256. Why? What's the benefit? What ...
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How much entropy is lost via hashing when you add known or low entropy data?

(I updated the title, as I think there was some confusion as to the question) Here's the question: For example, if I have a bit stream that is 64K bytes long and there is about 16 *8 bits worth of ...
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Advantages of combined PRNGs

This question is related to this one in intention, and this one in scope. Would I be guarding myself against future attacks on a single PRNG if I combine two (or more) together? I am thinking of ...
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Testing the Fortuna random number generator?

I have implemented the Fortuna random number generator as described in chapter 10 of "Practical Cryptography" (Ferguson and Schneier, Wiley, 2003), the result can be found at ...
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Why does Fortuna (RNG) require entropy sources to specify accumulator pool?

Re-reading my copy of Cryptography Engineering for the holidays, I was struck by the following question about the Fortuna RNG: Why require an entropy source specify which pool a random event should ...