[Cfrg] naive question: QC vs RC vs Moore-blip

Dan Brown <danibrown@blackberry.com> Mon, 08 May 2017 15:31 UTC

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From: Dan Brown <danibrown@blackberry.com>
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Thread-Topic: naive question: QC vs RC vs Moore-blip
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Date: Mon, 08 May 2017 15:31:03 +0000
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Subject: [Cfrg] naive question: QC vs RC vs Moore-blip
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Dear CFRG,

Please forgive my naivety on the matters below.
If quantum computers are realistic enough to warrant standards changes (now or soon), then what about other hypothetical computers, such as:

(1) computers that can do super high-precision, as in the "real computation" model (or whatever variant of this model that can implement Shamir's algorithm to factor using super-large integers in a polynomial (even linear?) number of integer arithmetic steps),

(2) sudden (single) blips exceeding the usual Moore's law (and variants) for future computing power (e.g. are sudden and new 100x faster transistor material, superconductors, photonics, less realistic than quantum computers)?

I don't know the established answers, but would speculate:

(a) quantum computers are deemed more realistic than each of (1) and (2),

(b) model (1) is known [?] to affect all algorithms equally, so we must just give up on it,

(c) most justifications for 128-bit security already include a margin of error for risk (2),

(d) 256-bit security (and variants) are meant to deal with (2).

Are these the established answers, or is there better answers? 

As a research issue, I'd like to know more about (b), if it is correct.

I'd like to know more about (a), the why of it, but am unlikely to understand.

Best regards,

Dan Brown