Re: [Cfrg] 25519 naming

David Leon Gil <coruus@gmail.com> Wed, 27 August 2014 13:18 UTC

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Date: Wed, 27 Aug 2014 09:18:53 -0400
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From: David Leon Gil <coruus@gmail.com>
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Subject: Re: [Cfrg] 25519 naming
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Cryptographers have, for quite a while, abused notation and
identified different, isomorphic, elliptic forms. Well, abuse of notation
strikes back.

Part of the problem is that calling a transfer of coördinates to a
different form a 'coördinate transform' is confusing. (I suspect that most
people don't have sufficient topology to realize that different forms have
different topologies.)

Mathematicians have a perfectly good terminology already; why not simply
adopt that, and be explicit about the maps used to transfer between forms?


On Monday, August 25, 2014, D. J. Bernstein <djb@cr.yp.to> wrote:
>
> All relevant coordinate systems already have standard names in the
> literature, and I would suggest sticking to those names whenever it's
> necessary to discuss the coordinate systems per se:
>