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Alternative Elliptic Curve Representations

Approval announcement
Draft of message to be sent after approval:


From: The IESG <>
To: IETF-Announce <>
Cc: Mohit Sethi <>, The IESG <>,,,,,,
Subject: Document Action: 'Alternative Elliptic Curve Representations' to Informational RFC (draft-ietf-lwig-curve-representations-23.txt)

The IESG has approved the following document:
- 'Alternative Elliptic Curve Representations'
  (draft-ietf-lwig-curve-representations-23.txt) as Informational RFC

This document is the product of the Light-Weight Implementation Guidance
Working Group.

This document was developed in LWIG in support of work in the working group but is itself outside the scope of the working group.  When the work began, other working groups were considered by responsible ADs and the choice was made to continue the work within LWIG despite being out of scope (then and now).

The IESG contact persons are Erik Kline and Éric Vyncke.

A URL of this Internet Draft is:

Ballot Text

Technical Summary

   This document specifies how to represent Montgomery curves and
   (twisted) Edwards curves as curves in short-Weierstrass form and
   illustrates how this can be used to carry out elliptic curve
   computations using existing implementations of, e.g., ECDSA and ECDH
   using NIST prime curves.  We also provide extensive background
   material that may be useful for implementers of elliptic curve

Working Group Summary

   Several security people in the working group explicitly highlighted
   their interest in this draft. This included Tero Kivinen, Hannes Tschofenig,
   and Carsten Bormann. Since this draft is crypto-heavy only a few working
   group members were able to provide detailed reviews. Nikolas Rösener
   has reviewed and implemented the draft. No objections were raised
   against this draft at any stage in the working group. 

Document Quality

   There is one known open implementation of the draft which is also
   noted in section 7. The document was sent to the Crypto Review Panel
   for review through Alexey Melnikov.  Stanislav Smyshlyaev reviewed the
   entire document and the formulae. All the minor comments from
   Stanislav and his team were addressed by the author. 


   The document shepherd is Mohit Sethi.

   The Area Director is Erik Kline.


   The COSE registrations are currently not resolved.  Some discussion
   by folks with knowledge/experience in this area would be welcome.


   This document requests:

      * 2 PKIX/CMS code points
      * several JOSE registrations
      * several COSE registrations

   At this time, the state of the COSE registrations is a matter of some

RFC Editor Note