Re: [Cfrg] RGLC on draft-irtf-cfrg-pairing-friendly-curves-07 Wed, 08 July 2020 21:59 UTC

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Date: Wed, 8 Jul 2020 14:59:16 -0700
To: Armando Faz <>
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Subject: Re: [Cfrg] RGLC on draft-irtf-cfrg-pairing-friendly-curves-07
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Hello CFRG,

Armando, thanks for the careful feedback.

One quick question for the whole group:

Armando Faz <> wrote:
> My second suggestion is to include suites for hashing to G1 and
> G2 because this is a common requirement in cryptographic protocols.
> (Methods are already defined in the hash_to_curve draft, so it might
> just require to define the corresponding suites).

Since neither hash-to-curve nor pairing-friendly-curves is finalized,
it seems like these hash-to-curve suites could go in either document.

Stating the obvious:

- one advantage of putting them in p-f-c is that it decouples the
  two documents somewhat---if p-f-c changes after h-2-c is finalized
  there's no problem updating the suites.

- on the other hand, putting the suites in h-2-c might make them
  slightly easier to discover down the road; but maybe this issue
  can be addressed by adding a pointer from h-2-c to p-f-c.

In either case, it seems like the BLS12-381 suite currently defined
in h-2-c ought to live in the same place as the suites for the other
curves that are defined in p-f-c, no?

Further thoughts would be appreciated!

Best regards,