Re: [Cfrg] Rigidity and performance
Robert Ransom <rransom.8774@gmail.com> Wed, 10 September 2014 09:32 UTC
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Date: Wed, 10 Sep 2014 02:31:58 -0700
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From: Robert Ransom <rransom.8774@gmail.com>
To: Michael Hamburg <mike@shiftleft.org>
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Cc: IRTF Crypto Forum Research Group <cfrg@irtf.org>
Subject: Re: [Cfrg] Rigidity and performance
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On 9/9/14, Michael Hamburg <mike@shiftleft.org> wrote: > (2^424 - 2^212 - 1) / 11 > Faster than the above prime but has a “cofactor"; clearly worse than > Goldilocks unless you need 5 mod 8. But the prime (which determines the multiplicative-group structure, and thus the square-root algorithm) is congruent to 3 mod 4. Using a composite modulus for fast coordinate operations doesn't change that. Robert Ransom
- [Cfrg] Rigidity and performance Michael Hamburg
- Re: [Cfrg] Rigidity and performance Robert Ransom
- Re: [Cfrg] Rigidity and performance Robert Ransom