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Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 4.0 Message Specification

Approval announcement
Draft of message to be sent after approval:


From: The IESG <>
To: IETF-Announce <>
Cc:,, Russ Housley <>,,, The IESG <>,,
Subject: Protocol Action: 'Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 4.0 Message Specification' to Proposed Standard (draft-ietf-lamps-rfc5751-bis-11.txt)

The IESG has approved the following document:
- 'Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 4.0
   Message Specification'
  (draft-ietf-lamps-rfc5751-bis-11.txt) as Proposed Standard

This document is the product of the Limited Additional Mechanisms for PKIX
and SMIME Working Group.

The IESG contact persons are Benjamin Kaduk and Eric Rescorla.

A URL of this Internet Draft is:

Ballot Text

  Technical Summary:

    This document specifies the message handling for S/MIME 4.0.
    The changes since S/MIME 3.2 include required support for
    authenticated encryption, increased RSA key sizes, moving old
    cryptographic algorithms to historic status, and requiring support
    for AES-256 GCM, ChaCha200-Poly1305, SHA-512, ECDSA with P-256,
    EdDSA, and Ed25519.

  Working Group Summary:

    There is strong consensus for this document in the LAMPS WG.

  Document Quality:

    S/MIME has wide support, and several implementers have said that
    they will implement the new features in this document.


    Russ Housley is the document shepherd.
    Eric Rescorla is the responsible area director.

RFC Editor Note