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    SubjectRe: [PATCH] API for true Random Number Generators to add entropy (2.6.11)
    On Tue, 2005-03-29 at 20:46 +1000, Herbert Xu wrote:
    > On Tue, Mar 29, 2005 at 02:50:28PM +0400, Evgeniy Polyakov wrote:
    > >
    > > Without ability speed this up in kernel, we completely [ok, almost]
    > > loose all RNG advantages.
    > Well if you can demonstrate that you're getting a higher rate of
    > throughput from your RNG by doing this in kernel space vs. doing
    > it in user space please let me know.

    Quote from VIA RNG crypto analysis:

    "Bitrate. The RNG generates output at significantly
    higher rates than most PC-based randomness resources.
    Raw bits are produced at rates of 30 to 50 Mbits/sec,
    and whitened bits were observed at rates of 4 to 9
    Mbits/sec. Variations in output rates depend on the
    RNG configuration and the oscillator rates. PRNGs
    seeded with the Nehemiah RNG should be able to
    easily sustain output in excess of 2 Mbits of entropy per
    second, which should eliminate blocked PRNG reads in
    virtually all applications."

    While raw bits reading from hw_random on the fastest
    VIA boards can exceed 55mbits per second
    [above quite was taken from VIA C3 Nehemiah analysis],
    it is not evaluated in rngd and is not written
    back to the /dev/random.

    David provided his patch exactly because of
    "Adding this can dramatically improve the performance of
    /dev/random on small embedded systems which do not
    generate much entropy."
    and it works.

    Evgeniy Polyakov

    Crash is better than data corruption -- Arthur Grabowski
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