Re: [Cfrg] I-D Action: draft-irtf-cfrg-hash-to-curve-04.txt

"Riad S. Wahby" <> Mon, 22 July 2019 20:22 UTC

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Date: Mon, 22 Jul 2019 16:22:45 -0400
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From: "Riad S. Wahby" <>
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Subject: Re: [Cfrg] I-D Action: draft-irtf-cfrg-hash-to-curve-04.txt
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On July 22, 2019 4:08:25 PM EDT, "Björn Haase" <> wrote:
>The second simple question IMO is P384. I'd not consider Icart's mapping
>as long as the patents apply. I'd use plain SWU here.

The generalized version of Simplified SWU given in -04 also applies to P384. So the question of which map to use for P384 is an instance of the broader question you asked, namely, are we comfortable with the IPR situation surrounding Simplified SWU? (I don't know! but maybe we'll understand more about this soon.)

So: if P256 ends up using Simplified SWU, P384 can as well.

(I certainly agree that we should be leery of the Icart IPR issues.)