Certificate Management Messages over CMS (CMC): Compliance Requirements
draft-ietf-lamps-rfc5274bis-11

LAMPS Working Group                                        J. Mandel, Ed
Internet-Draft                                              AKAYLA, Inc.
Obsoletes: 5274, 6402 (if approved)                        S. Turner, Ed
Intended status: Standards Track                                   sn3rd
Expires: 30 August 2026                                 26 February 2026

Certificate Management Messages over CMS (CMC): Compliance Requirements
                     draft-ietf-lamps-rfc5274bis-11

Abstract

   This document provides a set of compliance statements about the CMC
   (Certificate Management over CMS) enrollment protocol.  The ASN.1
   structures and the transport mechanisms for the CMC enrollment
   protocol are covered in other documents.  This document provides the
   information needed to make a compliant version of CMC.

   This document obsoletes RFC 5274 and RFC 6402.

About This Document

   This note is to be removed before publishing as an RFC.

   Status information for this document may be found at
   https://datatracker.ietf.org/doc/draft-ietf-lamps-rfc5274bis/.

   Discussion of this document takes place on the WG LAMPS mailing list
   (mailto:spasm@ietf.org), which is archived at
   https://mailarchive.ietf.org/arch/browse/spasm/.  Subscribe at
   https://www.ietf.org/mailman/listinfo/spasm/.

   Source for this draft and an issue tracker can be found at
   https://github.com/TBD.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Requirements Terminology  . . . . . . . . . . . . . . . . . .   5
   4.  Changes since RFC 5274 and 6402 . . . . . . . . . . . . . . .   5
   5.  Requirements for All Entities . . . . . . . . . . . . . . . .   5
     5.1.  Cryptographic Algorithm Requirements  . . . . . . . . . .   6
     5.2.  Controls  . . . . . . . . . . . . . . . . . . . . . . . .   7
     5.3.  CRMF Feature Requirements . . . . . . . . . . . . . . . .   9
   6.  Requirements for Clients  . . . . . . . . . . . . . . . . . .  10
   7.  Requirements for Servers  . . . . . . . . . . . . . . . . . .  10
   8.  Requirements for EEs  . . . . . . . . . . . . . . . . . . . .  10
   9.  Requirements for RAs  . . . . . . . . . . . . . . . . . . . .  10
   10. Requirements for CAs  . . . . . . . . . . . . . . . . . . . .  10

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   11. Security Considerations . . . . . . . . . . . . . . . . . . .  11
   12. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  11
   13. References  . . . . . . . . . . . . . . . . . . . . . . . . .  11
     13.1.  Normative References . . . . . . . . . . . . . . . . . .  11
     13.2.  Informative References . . . . . . . . . . . . . . . . .  13
   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  13
   Contributors  . . . . . . . . . . . . . . . . . . . . . . . . . .  14
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  14

1.  Introduction

   The CMC (Certificate Management over CMS) protocol is designed in
   terms of a client/server relationship.  In the simplest case, the
   client is the requestor of the certificate (i.e., the End-Entity
   (EE)) and the server is the issuer of the certificate (i.e., the
   Certification Authority (CA)).  The introduction of a Registration
   Authority (RA) into the set of agents complicates the picture only
   slightly.  The RA becomes the server with respect to the certificate
   requestor, and it becomes the client with respect to the certificate
   issuer.  Any number of RAs can be inserted into the picture in this
   manner.

   The RAs may serve specialized purposes that are not currently covered
   by this document.  One such purpose would be a Key Escrow agent.  As
   such, all certificate requests for encryption keys would be directed
   through this RA and it would take appropriate action to do the key
   archival.  Key recovery requests could be defined in the CMC
   methodology allowing for the Key Escrow agent to perform that
   operation acting as the final server in the chain of agents.

   If there are multiple RAs in the system, it is considered normal that
   not all RAs will see all certificate requests.  The routing between
   the RAs may be dependent on the content of the certificate requests
   involved.

   This document is divided into six sections, each section specifying
   the requirements that are specific to a class of agents in the CMC
   model.  These are 1) all Entities, 2) all Servers, 3) all Clients, 4)
   all End-Entities, 5) all Registration Authorities, 6) all
   Certification Authorities.

   This document obsoletes RFC 5274 [CMC-COMPv1] and RFC 6402
   [CMC-Updates].

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2.  Terminology

   There are several different terms, abbreviations, and acronyms used
   in this document that we define here for convenience and consistency
   of usage:

   End-Entity (EE):  Refers to the entity that owns a key pair and for
      whom a certificate is issued.

   Registration Authority (RA) or Local RA (LRA):  Refers to an entity
      that acts as an intermediary between the EE and the CA.  Multiple
      RAs can exist between the End-Entity and the Certification
      Authority.  RAs may perform additional services such as key
      generation or key archival.  This document uses the term RA for
      both RA and LRA.

   Certification Authority (CA):  Refers to the entity that issues
      certificates.

   Client:  Refers to an entity that creates a PKI Request.  In this
      document, both RAs and EEs can be clients.

   Server:  Refers to the entities that process PKI Requests and create
      PKI Responses.  In this document both CAs and RAs can be servers.

   PKCS #10:  Refers to the Public Key Cryptography Standard #10
      [PKCS10], which defines a certification request syntax.

   CRMF:  Refers to the Certificate Request Message Format RFC [CRMF].
      CMC uses this certification request syntax defined in this
      document as part of the protocol.

   CMS:  Refers to the Cryptographic Message Syntax RFC [CMS].  This
      document provides for basic cryptographic services including
      encryption and signing with and without key management.

   PKI Request/Response:  Refers to the requests/responses described in
      this document.  PKI Requests include certification requests,
      revocation requests, etc.  PKI Responses include certs-only
      messages, failure messages, etc.

   Proof-of-Identity:  Refers to the client proving they are who they
      say that they are to the server.

   Proof-of-Possession (POP):  Refers to a value that can be used to
      prove that the private key corresponding to a public key is in the
      possession and can be used by an End-Entity.

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   Transport wrapper:  Refers to the outermost CMS wrapping layer.

   Entity:  Refers to EE, RA (or LRA), or CA.

3.  Requirements Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

4.  Changes since RFC 5274 and 6402

   Merged [CMC-Updates] text.

   Added RA Identity Proof Witness and Response Body Controls to CMC
   Controls Attribute table.

   Updated the Cryptographic Algorithm Requirements, and added section
   to maintain backwards compatability.

      Replaced SHA-1 for SHA-256

      Replaced HMAC-SHA-1 for HMAC-SHA-256

   Updated the Introduction section, changed "all agents" to "all
   entities" in the overview to maintain consistency throughout the
   document, and re-numbered the section headers.

5.  Requirements for All Entities

   All [CMC-STRUCT] and [CMC-TRANS] compliance statements MUST be
   adhered to unless specifically stated otherwise in this document.

   All entities MUST support Full PKI Requests, Simple PKI Responses,
   and Full PKI Responses.  Servers SHOULD support Simple PKI Requests.

   All entities MUST support the use of the CRMF syntax for
   certification requests.  Support for the PKCS #10 syntax for
   certification requests SHOULD be implemented by servers.

   The extendedFailInfo field SHOULD NOT be populated in the
   CMCStatusInfoV2 object; the failInfo field SHOULD be used to relay
   this information.  If the extendedFailInfo field is used, it is
   suggested that an additional CMCStatusInfoV2 item exist for the same
   body part with a failInfo field.

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   All entities MUST implement the HTTP transport mechanism as defined
   in [CMC-TRANS].  Other transport mechanisms MAY be implemented.

5.1.  Cryptographic Algorithm Requirements

   All entities MUST verify RSA-SHA256 signatures in SignedData; (see
   [CMS-ALG2]).  Entities MAY verify other signature algorithms.

   All entities MUST generate RSA-SHA256 signatures for SignedData; (see
   [CMS-ALG2]).  Other signatures algorithms MAY be used for generation.

   All entities MUST support Advanced Encryption Standard (AES) as the
   content encryption algorithm for EnvelopedData; (see [CMS-AES]).
   Other content encryption algorithms MAY be implemented.

   All entities MUST support AES-Galois/Counter Mode (GCM) as the
   authenticated content encryption algorithm for AuthEnvelopedData;
   (see [CMS-AES-AE]).  They MUST also support a 12 octet nonce size and
   a 12 octet integrity check value (ICV) length.  Other content
   encryption algorithms MAY be implemented.

   All entities MUST support RSA as a key transport algorithm for
   EnvelopedData and AuthEnvelopedData; (see [CMS-ALG2]).  Other key
   transport algorithms MAY be implemented.

   If an entity supports key agreement for EnvelopedData or
   AuthEnvelopedData, it MUST support Diffie-Hellman; (see [CMS-DH]).

   If an entity supports PasswordRecipientInfo for EnvelopedData,
   AuthenticatedData, or AuthEnvelopedData it MUST support PBKDF2
   [PBKDF2] for key derivation algorithms.  It MUST support AES key wrap
   (see [AES-WRAP]) as the key encryption algorithm.

   If AuthenticatedData is supported, PasswordRecipientInfo MUST be
   supported.

   Algorithm requirements for the Identity Proof Version 2 control
   (Section 6.2.1 of [CMC-STRUCT]) are: SHA-256 MUST be implemented for
   hashAlgId.  HMAC-SHA256 MUST be implemented for macAlgId.

   Algorithm requirements for the Pop Link Witness Version 2 control
   (Section 6.3.1 of [CMC-STRUCT]) are: SHA-256 MUST be implemented for
   keyGenAlgorithm.  PBKDF2 [PBKDF2] MAY be implemented for
   keyGenAlgorithm.  HMAC-SHA256 MUST be implemented for macAlgorithm.

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   Algorithm requirements for the Encrypted POP and Decrypted POP
   controls (Section 6.7 of [CMC-STRUCT]) are: SHA-256 MUST be
   implemented for witnessAlgID.  HMAC-SHA256 MUST be implemented for
   thePOPAlgID.

   Algorithm requirements for Publish Trust Anchors control
   (Section 6.15 of [CMC-STRUCT]) are: SHA-256 MUST be implemented for
   hashAlgorithm.

   If an EE generates DH keys for certification, it MUST support
   Section 4 of [DH-POP].  EEs MAY support Section 3 of [DH-POP].  CAs
   and RAs that do POP verification MUST support Section 4 of [DH-POP]
   and SHOULD support Section 3 of [DH-POP].

   EEs that need to use a signature algorithm for keys that cannot
   produce a signature MUST support Appendix C of [CMC-STRUCT] and MUST
   support the Encrypted/Decrypted POP controls.  CAs and RAs that do
   POP verification MUST support this signature algorithm and MUST
   support the Encrypted/Decrypted POP controls.

   For backwards compatibility with the previous version of CMC, servers
   MAY offer the algorithms specified therein, but SHOULD use the CMC
   requests to identify which certificates should be transitioned to
   more secure algorithms, if possible.

5.2.  Controls

   The following table lists the name and level of support required for
   each control.

      +============================+==========+==========+==========+
      | Control                    | EE       | RA       | CA       |
      +============================+==========+==========+==========+
      | Extended CMC Status Info   | MUST     | MUST     | MUST     |
      +----------------------------+----------+----------+----------+
      | CMC Status Info            | SHOULD   | SHOULD   | SHOULD   |
      +----------------------------+----------+----------+----------+
      | Identity Proof Version 2   | MUST     | MUST     | MUST     |
      +----------------------------+----------+----------+----------+
      | Identity Proof             | SHOULD   | SHOULD   | SHOULD   |
      +----------------------------+----------+----------+----------+
      | Identification             | MUST     | MUST     | MUST     |
      +----------------------------+----------+----------+----------+
      | POP Link Random            | MUST     | MUST     | MUST     |
      +----------------------------+----------+----------+----------+
      | POP Link Witness Version 2 | MUST     | MUST     | MUST     |
      +----------------------------+----------+----------+----------+
      | POP Link Witness           | SHOULD   | MUST     | MUST     |

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      +----------------------------+----------+----------+----------+
      | Data Return                | MUST     | MUST     | MUST     |
      +----------------------------+----------+----------+----------+
      | Modify Cert Request        | N/A      | MUST     | (2)      |
      +----------------------------+----------+----------+----------+
      | Add Extensions             | N/A      | MAY      | (1)      |
      +----------------------------+----------+----------+----------+
      | Transaction ID             | MUST     | MUST     | MUST     |
      +----------------------------+----------+----------+----------+
      | Sender Nonce               | MUST     | MUST     | MUST     |
      +----------------------------+----------+----------+----------+
      | Recipient Nonce            | MUST     | MUST     | MUST     |
      +----------------------------+----------+----------+----------+
      | Encrypted POP              | (4)      | (5)      | SHOULD   |
      +----------------------------+----------+----------+----------+
      | Decrypted POP              | (4)      | (5)      | SHOULD   |
      +----------------------------+----------+----------+----------+
      | RA POP Witness             | N/A      | SHOULD   | (1)      |
      +----------------------------+----------+----------+----------+
      | Get Certificate            | optional | optional | optional |
      +----------------------------+----------+----------+----------+
      | Get CRL                    | optional | optional | optional |
      +----------------------------+----------+----------+----------+
      | Revocation Request         | SHOULD   | SHOULD   | MUST     |
      +----------------------------+----------+----------+----------+
      | Registration Info          | SHOULD   | SHOULD   | SHOULD   |
      +----------------------------+----------+----------+----------+
      | Response Information       | SHOULD   | SHOULD   | SHOULD   |
      +----------------------------+----------+----------+----------+
      | Query Pending              | MUST     | MUST     | MUST     |
      +----------------------------+----------+----------+----------+
      | Confirm Cert.  Acceptance  | MUST     | MUST     | MUST     |
      +----------------------------+----------+----------+----------+
      | Publish Trust Anchors      | (3)      | (3)      | (3)      |
      +----------------------------+----------+----------+----------+
      | Authenticate Data          | (3)      | (3)      | (3)      |
      +----------------------------+----------+----------+----------+
      | Batch Request              | N/A      | MUST     | (2)      |
      +----------------------------+----------+----------+----------+
      | Batch Responses            | N/A      | MUST     | (2)      |
      +----------------------------+----------+----------+----------+
      | Publication Information    | optional | optional | optional |
      +----------------------------+----------+----------+----------+
      | Control Processed          | N/A      | MUST     | (2)      |
      +----------------------------+----------+----------+----------+
      | RA Identity Proof Witness  | N/A      | MUST     | (2)      |
      +----------------------------+----------+----------+----------+
      | Response Body              | (6)      | (6)      | N/A.     |

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      +----------------------------+----------+----------+----------+

                      Table 1: CMC Control Attributes

   Notes:

   1.  CAs SHOULD implement this control if designed to work with RAs.

   2.  CAs MUST implement this control if designed to work with RAs.

   3.  Implementation is optional for these controls.  We strongly
       suggest that they be implemented in order to populate client
       trust anchors.

   4.  EEs only need to implement this if (a) they support key agreement
       algorithms or (b) they need to operate in environments where the
       hardware keys cannot provide POP.

   5.  RAs SHOULD implement this if they implement RA POP Witness.

   6.  EE's SHOULD implement if designed to work with RAs and MUST
       implement if intended to be used in environments where RAs are
       used for identity validation or key generation.  RAs SHOULD
       implement and validate responses for consistency.

   Strong consideration should be given to implementing the Authenticate
   Data and Publish Trust Anchors controls as this gives a simple method
   for distributing trust anchors into clients without user
   intervention.

5.3.  CRMF Feature Requirements

   The following additional restrictions are placed on CRMF features:

   The registration control tokens id-regCtrl-regToken and id-regCtrl-
   authToken MUST NOT be used.  No specific CMC feature is used to
   replace these items, but generally the CMC controls identification
   and identityProof will perform the same service and are more
   specifically defined.

   The control token id-regCtrl-pkiArchiveOptions SHOULD NOT be
   supported.  An alternative method is under development to provide
   this functionality.

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   The behavior of id-regCtrl-oldCertID is not presently used.  It is
   replaced by issuing the new certificate and using the id-cmc-
   publishCert to remove the old certificate from publication.  This
   operation would not normally be accompanied by an immediate
   revocation of the old certificate; however, that can be accomplished
   by the id-cmc-revokeRequest control.

   The id-regCtrl-protocolEncrKey is not used.

6.  Requirements for Clients

   There are no additional requirements.

7.  Requirements for Servers

   There are no additional requirements.

8.  Requirements for EEs

   If an End-Entity implements Diffie-Hellman, it MUST implement either
   the DH-POP Proof-of-Possession as defined in Section 4 of [DH-POP] or
   the challenge-response POP controls id-cmc-encryptedPOP and id-cmc-
   decryptedPOP.

9.  Requirements for RAs

   RAs SHOULD be able to do delegated POP.  RAs implementing this
   feature MUST implement the id-cmc-lraPOPWitness control.

   All RAs MUST implement the promotion of the id-aa-cmc-unsignedData as
   covered in Section 3.2.3 of [CMC-STRUCT].

10.  Requirements for CAs

   Providing for CAs to work in an environment with RAs is strongly
   suggested.  Implementation of such support is strongly suggested as
   this permits the delegation of substantial administrative interaction
   onto an RA rather than at the CA.

   CAs MUST perform at least minimal checks on all public keys before
   issuing a certificate.  At a minimum, a check for syntax would occur
   with the POP operation.  Additionally, CAs SHOULD perform simple
   checks for known bad keys such as small subgroups for DSA-SHA1 and DH
   keys [SMALL-SUB-GROUP] or known bad exponents for RSA keys.

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   CAs MUST enforce POP checking before issuing any certificate.  CAs
   MAY delegate the POP operation to an RA for those cases where 1) a
   challenge/response message pair must be used, 2) an RA performs
   escrow of a key and checks for POP in that manner, or 3) an unusual
   algorithm is used and that validation is done at the RA.

   CAs SHOULD implement both the DH-POP Proof-of-Possession as defined
   in Section 4 of [DH-POP] and the challenge-response POP controls id-
   cmc-encryptedPOP and id-cmc-decryptedPOP.

11.  Security Considerations

   This document uses [CMC-STRUCT] and [CMC-TRANS] as building blocks to
   this document.  The security sections of those two documents are
   included by reference.

   Knowledge of how an entity is expected to operate is vital in
   determining which sections of requirements are applicable to that
   entity.  Care needs to be taken in determining which sections apply
   and fully implementing the necessary code.

   Cryptographic algorithms have and will be broken or weakened.
   Implementers and users need to check that the cryptographic
   algorithms listed in this document make sense from a security level.
   The IETF from time to time may issue documents dealing with the
   current state of the art.  Two examples of such documents are
   [SMALL-SUB-GROUP] and [HASH-ATTACKS].

12.  IANA Considerations

   This document does not require action from IANA.

13.  References

13.1.  Normative References

   [AES-WRAP] Schaad, J. and R. Housley, "Advanced Encryption Standard
              (AES) Key Wrap Algorithm", RFC 3394, DOI 10.17487/RFC3394,
              September 2002, <https://www.rfc-editor.org/rfc/rfc3394>.

   [CMC-STRUCT]
              Mandel, J. and S. Turner, "Certificate Management over CMS
              (CMC)", Work in Progress, Internet-Draft, draft-ietf-
              lamps-rfc5272bis-10, 6 February 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-lamps-
              rfc5272bis-10>.

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   [CMC-TRANS]
              Mandel, J. and S. Turner, "Certificate Management over CMS
              (CMC): Transport Protocols", Work in Progress, Internet-
              Draft, draft-ietf-lamps-rfc5273bis-10, 6 February 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-lamps-
              rfc5273bis-10>.

   [CMS]      Housley, R., "Cryptographic Message Syntax (CMS)", STD 70,
              RFC 5652, DOI 10.17487/RFC5652, September 2009,
              <https://www.rfc-editor.org/rfc/rfc5652>.

   [CMS-AES]  Schaad, J., "Use of the Advanced Encryption Standard (AES)
              Encryption Algorithm in Cryptographic Message Syntax
              (CMS)", RFC 3565, DOI 10.17487/RFC3565, July 2003,
              <https://www.rfc-editor.org/rfc/rfc3565>.

   [CMS-AES-AE]
              Housley, R., "Using AES-CCM and AES-GCM Authenticated
              Encryption in the Cryptographic Message Syntax (CMS)",
              RFC 5084, DOI 10.17487/RFC5084, November 2007,
              <https://www.rfc-editor.org/rfc/rfc5084>.

   [CMS-ALG2] Turner, S., "Using SHA2 Algorithms with Cryptographic
              Message Syntax", RFC 5754, DOI 10.17487/RFC5754, January
              2010, <https://www.rfc-editor.org/rfc/rfc5754>.

   [CMS-DH]   Rescorla, E., "Diffie-Hellman Key Agreement Method",
              RFC 2631, DOI 10.17487/RFC2631, June 1999,
              <https://www.rfc-editor.org/rfc/rfc2631>.

   [CRMF]     Schaad, J., "Internet X.509 Public Key Infrastructure
              Certificate Request Message Format (CRMF)", RFC 4211,
              DOI 10.17487/RFC4211, September 2005,
              <https://www.rfc-editor.org/rfc/rfc4211>.

   [DH-POP]   Schaad, J. and H. Prafullchandra, "Diffie-Hellman Proof-
              of-Possession Algorithms", RFC 6955, DOI 10.17487/RFC6955,
              May 2013, <https://www.rfc-editor.org/rfc/rfc6955>.

   [PBKDF2]   Kario, A., "Use of Password-Based Message Authentication
              Code 1 (PBMAC1) in PKCS #12 Syntax", RFC 9879,
              DOI 10.17487/RFC9879, September 2025,
              <https://www.rfc-editor.org/rfc/rfc9879>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/rfc/rfc2119>.

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   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.

13.2.  Informative References

   [CMC-COMPv1]
              Schaad, J. and M. Myers, "Certificate Management Messages
              over CMS (CMC): Compliance Requirements", RFC 5274,
              DOI 10.17487/RFC5274, June 2008,
              <https://www.rfc-editor.org/rfc/rfc5274>.

   [CMC-Updates]
              Schaad, J., "Certificate Management over CMS (CMC)
              Updates", RFC 6402, DOI 10.17487/RFC6402, November 2011,
              <https://www.rfc-editor.org/rfc/rfc6402>.

   [HASH-ATTACKS]
              Hoffman, P. and B. Schneier, "Attacks on Cryptographic
              Hashes in Internet Protocols", RFC 4270,
              DOI 10.17487/RFC4270, November 2005,
              <https://www.rfc-editor.org/rfc/rfc4270>.

   [PKCS10]   Nystrom, M. and B. Kaliski, "PKCS #10: Certification
              Request Syntax Specification Version 1.7", RFC 2986,
              DOI 10.17487/RFC2986, November 2000,
              <https://www.rfc-editor.org/rfc/rfc2986>.

   [SMALL-SUB-GROUP]
              Zuccherato, R., "Methods for Avoiding the "Small-Subgroup"
              Attacks on the Diffie-Hellman Key Agreement Method for S/
              MIME", RFC 2785, DOI 10.17487/RFC2785, March 2000,
              <https://www.rfc-editor.org/rfc/rfc2785>.

Acknowledgements

   Obviously, the authors of this version of the document would like to
   thank Jim Schaad and Michael Myers for their work on the previous
   version of this document.

   Thank you to Mike Bishop, Mohamed Boucadair, and Erik Kline for
   reviewing the document and providing comments.

   The acknowledgment from the previous version of this document
   follows:

Mandel, Ed & Turner, Ed  Expires 30 August 2026                [Page 13]
Internet-Draft               CMC: Compliance               February 2026

   The authors and the PKIX Working Group are grateful for the
   participation of Xiaoyi Liu and Jeff Weinstein in helping to author
   the original versions of this document.

   The authors would like to thank Brian LaMacchia for his work in
   developing and writing up many of the concepts presented in this
   document.  The authors would also like to thank Alex Deacon and Barb
   Fox for their contributions.

Contributors

   Jim Schaad
   August Cellars

   Michael Myers
   TraceRoute Security, Inc.

Authors' Addresses

   Joseph Mandel
   AKAYLA, Inc.
   Email: joe@akayla.com

   Sean Turner
   sn3rd
   Email: sean@sn3rd.com

Mandel, Ed & Turner, Ed  Expires 30 August 2026                [Page 14]