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Under linux you run out of system Entropy when trying to generate GPG keys unless you use /dev/urandom. Under windows, you get the speed of /dev/urandom without any tweaks. Does windows have that much extra entropy, or are the keys just less secure?

This is a link that discusses /dev/urandom generating less secure keys for those that aren't familiar with why this might be a problem.

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I would say it mostly depends on the entropy pool and how entropy is collected.

I found this:

Microsoft Windows releases newer than 95A feature the CryptoAPI (CAPI) API that gathers entropy in a similar fashion to Linux kernel's /dev/random.[11] Windows's CryptoAPI uses the binary registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Cryptography\RNG\Seed to store a seeded value from all of its entropy sources.[12] Because CryptoAPI is closed-source, some free and open source software applications running on the Windows platform use other measures to get randomness. For example, GnuPG, as of version 1.06, uses a variety of sources such as the number of free bytes in memory that combined with a random seed generate the desired randomness it needs.[13] Programmers using CAPI can get entropy by calling CAPI's CryptGenRandom(), after properly initialising it

I hope it helps or points you in the right direction to follow.

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Yea, unfortunately I had seen that, but still don't know if they pass the test of true randomness.... – boatcoder Jul 26 '12 at 15:48

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