Re: [Cfrg] Requirements for curve candidate evaluation update

William Whyte <wwhyte@securityinnovation.com> Wed, 13 August 2014 01:49 UTC

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From: William Whyte <wwhyte@securityinnovation.com>
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Date: Tue, 12 Aug 2014 21:49:03 -0400
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To: Watson Ladd <watsonbladd@gmail.com>, Benjamin Black <b@b3k.us>
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Subject: Re: [Cfrg] Requirements for curve candidate evaluation update
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[Benjamin Black]
> 5. No changes to coordinate wire formats.

[Watson Ladd]
> Does this mean just Weierstrass? Or is a change to Edwards somehow not
a change in the wire format? (Of course this doesn't constrain the
curves either)

Requirement 5 strikes me as entirely unnecessary. Why is it important that
two different curves have the same wire format? The wire format can be one
of the things identified by the curve identifier, and each curve will have a
certain amount of custom code anyway; why does it matter if this custom code
includes code to interpret the wire format? I'd like to see this requirement
more thoroughly justified.

William