[CFRG] Re: Comments on draft-sigma Section 3.5
Michele Orrù <lists@tumbolandia.net> Thu, 08 October 2026 00:01 UTC
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From: Michele Orrù <lists@tumbolandia.net>
Date: Wed, 07 Oct 2026 17:00:00 -0700
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To: Watson Ladd <watsonbladd@gmail.com>
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Subject: [CFRG] Re: Comments on draft-sigma Section 3.5
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Hi Watson, Yes, agreed. The identity was originally forbidden mostly by following BBS and VOPRF, rather than because such equations are always useless. The upcoming Sigma Protocols specification allows the identity element; see Section 3.5: https://mmaker.github.io/draft-irtf-cfrg-sigma-protocols/draft-irtf-cfrg-sigma-protocols.html#name-instance-validation I also mentioned this direction in a previous email: https://mailarchive.ietf.org/arch/msg/cfrg/bokULgMfJvx6_A1sBkwv9HrKMs8/ Best, -- Michele On Tue, Oct 6, 2026 at 10:21 AM Watson Ladd <watsonbladd@gmail.com> wrote: > > The Sigma protocols draft disallows identity elements in the image, > saying the equations are satisfied by the all zero vector and thus are > useless. I don't follow: while a singular equation might have a > trivially satisfiable witness, it's useful to be able to express > linear constraints on scalar values that appear in other equations. > I'm not sure why this restriction appears given that. > > Sincerely, > Watson > > -- > Astra mortemque praestare gradatim > _______________________________________________ > CFRG mailing list -- cfrg@irtf.org > To unsubscribe send an email to cfrg-leave@irtf.org
- [CFRG] Comments on draft-sigma Section 3.5 Watson Ladd
- [CFRG] Re: Comments on draft-sigma Section 3.5 Michele Orrù