[CFRG] Re: I-D Action: draft-irtf-cfrg-pairing-friendly-curves-12.txt

[John Mattsson <[e-mail]>]

Hi,

I think it would be good to try to publish this asap. My two cents would be to focus on specifying:

- BLS12_381
- One BLS24 curve, one BLS48 curve, or both. I think many people might want some security margin when deploying pairing-based crypto.
-  The ZCash serialization format

I don't think "Selection of Pairing-Friendly Curves" including what is standardized in other SDO is essential. I think BN462 could be removed. less is more. Correctly if I am wrong but my understanding is that BLS12_381 is superior to BN462. Security of Pairing-Friendly Curve could be moved to security consideration or an appendix.

Cheers,
John

On 2025-11-02, 22:17, "[e-mail]" <[e-mail]> wrote:

Internet-Draft draft-irtf-cfrg-pairing-friendly-curves-12.txt is now
available. It is a work item of the Crypto Forum (CFRG) RG of the IRTF.

   Title:   Pairing-Friendly Curves
   Authors: Yumi Sakemi
            Satoru Kanno
            Riad S. Wahby
   Name:    draft-irtf-cfrg-pairing-friendly-curves-12.txt
   Pages:   54
   Dates:   2025-11-02

Abstract:

   Pairing-based cryptography, a subfield of elliptic curve
   cryptography, has received attention due to its flexible and
   practical functionality.  Pairings are special maps defined using
   elliptic curves and it can be applied to construct several
   cryptographic protocols such as identity-based encryption, attribute-
   based encryption, and so on.  At CRYPTO 2016, Kim and Barbulescu
   proposed an efficient number field sieve algorithm named exTNFS for
   the discrete logarithm problem in a finite field.  Several types of
   pairing-friendly curves such as Barreto-Naehrig curves are affected
   by the attack.  In particular, a Barreto-Naehrig curve with a 254-bit
   characteristic was adopted by a lot of cryptographic libraries as a
   parameter of 128-bit security, however, it ensures no more than the
   100-bit security level due to the effect of the attack.  In this
   memo, we list the security levels of certain pairing-friendly curves,
   and motivate our choices of curves.  First, we summarize the adoption
   status of pairing-friendly curves in standards, libraries and
   applications, and classify them in the 128-bit, 192-bit, and 256-bit
   security levels.  Then, from the viewpoints of "security" and "widely
   used", we select the recommended pairing-friendly curves considering
   exTNFS.

The IETF datatracker status page for this Internet-Draft is:
https://datatracker.ietf.org/doc/draft-irtf-cfrg-pairing-friendly-curves/

There is also an HTML version available at:
https://www.ietf.org/archive/id/draft-irtf-cfrg-pairing-friendly-curves-12.html

A diff from the previous version is available at:
https://author-tools.ietf.org/iddiff?url2=draft-irtf-cfrg-pairing-friendly-curves-12

Internet-Drafts are also available by rsync at:
rsync.ietf.org::internet-drafts