Re: DSA speed vs AES speed


Pubkeybreaker wrote:
"And the question is: approximately, how much time should we expect
this
encryption to take? Much more than 10 seconds? Much less? Same order of
magnitude? "


Microseconds, at most.

They didn't strictly say a desktop processor. A microsecond on a
standard 8051 is 12 cycles whcih is the time it takes to execute a "1
instruction cycle" opcode.

IIRC an AES implementation (from the submission papers) was thousands
of cycles. I don't recall the exact figure but let's say something
like 2000 cycles just for the sake of discussion (cuz that sounds about
right, I think in reality it's probably lower but that doesn't matter).

So on a CPU where 512-bit DSA takes "10 seconds" I doubt AES is running
on an Athlon64 or Pentium4.

Tom

.

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