X.509 Extended Key Usage (EKU) for configuration, updates and safety-communication
draft-ietf-lamps-automation-keyusages-08

LAMPS Working Group                                         H. Brockhaus
Internet-Draft                                                   Siemens
Intended status: Standards Track                            D. Goltzsche
Expires: 11 October 2025                                Siemens Mobility
                                                            9 April 2025

 X.509 Extended Key Usage (EKU) for configuration, updates and safety-
                             communication
                draft-ietf-lamps-automation-keyusages-08

Abstract

   RFC 5280 defines the Extended Key Usage (EKU) extension and several
   extended key purposes (KeyPurposeIds) for use with that extension in
   X.509 certificates.  This document defines KeyPurposeIds for general-
   purpose and trust anchor configuration files, for software and
   firmware update packages, and for safety-critical communication to be
   included in the EKU extension of X.509 v3 public key certificates.

Status of This Memo

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   This Internet-Draft will expire on 11 October 2025.

Copyright Notice

   Copyright (c) 2025 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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   This document is subject to BCP 78 and the IETF Trust's Legal
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   Please review these documents carefully, as they describe your rights
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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions and Definitions . . . . . . . . . . . . . . . . .   4
   3.  Extended Key Purpose for configuration files, update packages
           and safety-communication  . . . . . . . . . . . . . . . .   4
   4.  Including the Extended Key Purpose in Certificates  . . . . .   5
   5.  Implications for a Certification Authority  . . . . . . . . .   6
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   7
   7.  Privacy Considerations  . . . . . . . . . . . . . . . . . . .   7
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   7
   9.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .   8
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .   8
     10.1.  Normative References . . . . . . . . . . . . . . . . . .   8
     10.2.  Informative References . . . . . . . . . . . . . . . . .   9
   Appendix A.  ASN.1 Module . . . . . . . . . . . . . . . . . . . .  11
   Appendix B.  Use Cases  . . . . . . . . . . . . . . . . . . . . .  12
   Appendix C.  History of Changes . . . . . . . . . . . . . . . . .  13
   Contributors  . . . . . . . . . . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  15

1.  Introduction

   Key purposes (KeyPurposeIds) added to the certificate's extended key
   usage extension as defined in [RFC5280] are meant to express intent
   as to the purpose of the named usage, for humans and for complying
   libraries.  A full list of KeyPurposeIds is maintained in the IANA
   registry "SMI Security for PKIX Extended Key Purpose"
   [SMI-PKIX-PURPOSE].  The use of the anyExtendedKeyUsage KeyPurposeId,
   as defined in Section 4.2.1.12 of [RFC5280], is generally considered
   a poor practice.

   This document defines KeyPurposeIds for certificates that are used
   for the following purposes, among others:

   *  Validating signatures of general-purpose software configuration
      files.

   *  Validating signatures of trust anchor configuration files.

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   *  Validating signatures of software and firmware update packages.

   *  Authenticating communication endpoints authorized for safety-
      critical communication.

   If the purpose of an issued certificate is not restricted, i.e., the
   type of operations for which a public key contained in the
   certificate can be used in unintended ways, the risk of cross-
   application attacks is increased.  Failure to ensure adequate
   segregation of duties means that an application or system that
   generates the public/private keys and applies for a certificate to
   the operator Certification Authority (CA) could obtain a certificate
   that can be misused for tasks that this application or system is not
   entitled to perform.  For example, management of trust anchors is a
   particularly critical task.  A device could potentially accept a
   trust anchor configuration file signed by a service that uses a
   certificate with no Extended Key Usage (EKU) or with the KeyPurposeId
   id-kp-codeSigning (Section 4.2.1.12 of [RFC5280]) or id-kp-
   documentSigning [RFC9336].  A device should only accept trust anchor
   configuration files if the file is verified with a certificate that
   has been explicitly issued for this purpose.

   The KeyPurposeId id-kp-serverAuth (Section 4.2.1.12 of [RFC5280]) can
   be used to identify that the certificate is for a TLS WWW server, and
   the KeyPurposeId id-kp-clientAuth (Section 4.2.1.12 of [RFC5280]) can
   be used to identify that the certificate is for a TLS WWW client.
   However, there are currently no KeyPurposeIds for usage with X.509
   certificates for safety-critical communication.

   This document addresses the above problems by defining keyPurposeIds
   for the EKU extension of X.509 public key certificates.  These
   certificates are either used for signing files (general-purpose
   configuration and trust anchor configuration files, software and
   firmware update packages) or are used for safety-critical
   communication.

   Vendor-defined KeyPurposeIds used within a PKI governed by vendors
   typically do not pose interoperability concerns, as non-critical
   extensions can be safely ignored if unrecognized.  However, using
   KeyPurposeIds outside of their intended vendor-controlled environment
   or in ExtendedKeyUsage extensions that have been marked critical can
   lead to interoperability issues.  Therefore, it is advisable not to
   rely on vendor-defined KeyPurposeIds.  Instead, this specification
   defines standard KeyPurposeIds to ensure interoperability across
   various vendors and industries.

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   The definitions of theses KeyPurposeIds are intentionally broad to
   allow their use in different deployments even though they were
   initially motivated by industrial automation and rail automation, see
   Appendix B.  The details for each deployment needs to be described in
   the relevant technical standards and certificate policies.

2.  Conventions and Definitions

   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.

   This document uses terms defined in [RFC5280].  X.509 certificate
   extensions are defined using ASN.1 [X.680] and [X.690].

   The term 'safety-critical communication' refers to communication that
   could, under certain conditions, lead to a state in which human life,
   health, property, or the environment is endangered.  For the
   definition of 'safety' see [NIST_Glossary] and [ISO.IEC.IEEE_12207].

3.  Extended Key Purpose for configuration files, update packages and
    safety-communication

   This specification defines the KeyPurposeIds id-kp-configSigning, id-
   kp-trustAnchorConfigSigning, id-kp-updatePackageSigning, and id-kp-
   safetyCommunication.  These KeyPurposeIds are used, respectively,
   for: signing general-purpose configuration files or trust anchor
   configuration files, signing software or firmware update packages, or
   authenticating communication peers for safety-critical communication.
   As described in Section 4.2.1.12 of [RFC5280], "[i]f the [extended
   key usage] extension is present, then the certificate MUST only be
   used for one of the purposes indicated" and "[i]f multiple [key]
   purposes are indicated the application need not recognize all
   purposes indicated, as long as the intended purpose is present".

   None of the KeyPurposeIds specified in this document are
   intrinsically mutually exclusive.  Instead, the acceptable
   combinations of those KeyPurposeIds with others specified in this
   document and with other KeyPurposeIds specified elsewhere are left to
   the technical standards of the respective application and the
   certificate policy of the respective PKI.  For example, a technical
   standard may specify: 'Different keys and certificates must be used
   for safety communication and for trust anchor updates, and a relying
   party must ignore the KeyPurposeId id-kp-trustAnchorConfigSigning if
   id-kp-safetyCommunication is one of the specified key purposes in a
   certificate.'  The certificate policy for example may specify: 'The

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   id-kp-safetyCommunication KeyPuposeId should not be included in an
   issued certificate together with the KeyPurposeId id-kp-
   trustAnchorConfigSigning.'  Technical standards and certificate
   policies of different applications may specify other rules.  Further
   considerations on prohibiting combinations of KeyPurposeIds is
   described in Section 6.

   Systems or applications that verify the signature of a general-
   purpose configuration file or trust anchor configuration file, the
   signature of a software or firmware update package, or the
   authentication of a communication peer for safety-critical
   communication SHOULD require that corresponding KeyPurposeIds be
   specified by the EKU extension.  If the certificate requester knows
   the certificate users are mandated to use these KeyPurposeIds, it
   MUST enforce their inclusion.  Additionally, such a certificate
   requester MUST ensure that the KeyUsage extension be set to
   digitalSignature for signature verification, to keyEncipherment for
   public key encryption, and keyAgreement for key agreement.

4.  Including the Extended Key Purpose in Certificates

   [RFC5280] specifies the EKU X.509 certificate extension for use on
   end entity certificates.  The extension indicates one or more
   purposes for which the certified public key is valid.  The EKU
   extension can be used in conjunction with the Key Usage (KU)
   extension, which indicates the set of basic cryptographic operations
   for which the certified key may be used.  The EKU extension syntax is
   repeated here for convenience:

      ExtKeyUsageSyntax  ::=  SEQUENCE SIZE (1..MAX) OF KeyPurposeId

      KeyPurposeId  ::=  OBJECT IDENTIFIER

   As described in [RFC5280], the EKU extension may, at the option of
   the certificate issuer, be either critical or non-critical.  The
   inclusion of KeyPurposeIds id-kp-configSigning, id-kp-
   trustAnchorConfigSigning, id-kp-updatePackageSigning, and id-kp-
   safetyCommunication in a certificate indicates that the public key
   encoded in the certificate has been certified for the following
   usages:

   *  id-kp-configSigning

      A public key contained in a certificate containing the
      KeyPurposeId id-kp-configSigning may be used for verifying
      signatures of general-purpose configuration files of various
      formats (e.g., XML, YAML, or JSON).  Configuration files are used
      to configure hardware or software.

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   *  id-kp-trustAnchorConfigSigning

      A public key contained in a certificate containing the
      KeyPurposeId id-kp-trustAnchorConfigSigning may be used for
      verifying signatures of trust anchor configuration files of
      various formats (e.g., XML, YAML, or JSON).  Trust anchor
      configuration files are used to add or remove trust anchors to the
      trust store of a device.

   *  id-kp-updatePackageSigning

      A public key contained in a certificate containing the
      KeyPurposeId id-kp-updatePackageSigning may be used for verifying
      signatures of software or firmware update packages.  Update
      packages are used to install software (including bootloader,
      firmware, safety-related applications, and others) on systems.

   *  id-kp-safetyCommunication

      A public key contained in a certificate containing the
      KeyPurposeId id-kp-safetyCommunication may be used to authenticate
      a communication peer for safety-critical communication based on
      TLS or other protocols.

      id-kp  OBJECT IDENTIFIER  ::=
          { iso(1) identified-organization(3) dod(6) internet(1)
            security(5) mechanisms(5) pkix(7) 3 }

      id-kp-configSigning             OBJECT IDENTIFIER ::= { id-kp 41 }
      id-kp-trustAnchorConfigSigning  OBJECT IDENTIFIER ::= { id-kp 42 }
      id-kp-updatePackageSigning      OBJECT IDENTIFIER ::= { id-kp 43 }
      id-kp-safetyCommunication       OBJECT IDENTIFIER ::= { id-kp 44 }

5.  Implications for a Certification Authority

   The procedures and practices employed by a certification authority
   must ensure that the correct values for the EKU extension as well as
   the KU extension are inserted in each certificate that is issued.
   The inclusion of the id-kp-configSigning, id-kp-
   trustAnchorConfigSigning, id-kp-updatePackageSigning, and id-kp-
   safetyCommunication KeyPurposeIds does not preclude the inclusion of
   other KeyPurposeIds.

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6.  Security Considerations

   The Security Considerations of [RFC5280] are applicable to this
   document.  These extended key usage key purposes do not introduce new
   security risks but instead reduce existing security risks by
   providing the means to identify if a certificate is generated to
   verify the signature of a general-purpose or trust anchor
   configuration file, the signature of a software or firmware update
   package, or the authentication of a communication peer for safety-
   critical communication.

   To reduce the risk of specific cross-protocol attacks, the relying
   party may additionally prohibit use of specific combinations of
   KeyPurposeIds.  The procedure for allowing or disallowing
   combinations of KeyPurposeIds using excluded KeyPurposeId and
   permitted KeyPurposeId, as carried out by a relying party, is defined
   in Section 4 of [RFC9336].  The technical standards and certificate
   policies of the application should explicitly enumerate requirements
   for excluded or permitted KeyPurposeIds or their combinations.  It is
   out of scope of this document to enumerate those, but an example of
   excluded KeyPurposeIds can be the presence of the anyExtendedKeyUsage
   KeyPurposeId.  Examples of allowed KeyPurposeIds combinations can be
   the presence of id-kp-safetyCommunication together with id-kp-
   clientAuth or id-kp-serverAuth.

7.  Privacy Considerations

   In some protocols, e.g., TLS 1.2 [RFC5246], certificates are
   exchanged in the clear.  In other protocols, e.g., TLS 1.3 [RFC8446],
   the certificates are encrypted.  The inclusion of the EKU extension
   can help an observer determine the purpose of the certificate.  In
   addition, if the certificate is issued by a public certification
   authority, the inclusion of an EKU extension can help an attacker to
   monitor the Certificate Transparency logs [RFC9162] to identify the
   purpose of the certificate which may reveal private information of
   the certificate subject.

8.  IANA Considerations

   IANA is requested to register the following ASN.1 [X.680] module OID
   in the "SMI Security for PKIX Module Identifier" registry
   [SMI-PKIX-MOD].  This OID is defined in Appendix A.

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          +=========+=============================+============+
          | Decimal | Description                 | References |
          +=========+=============================+============+
          | TBD1    | id-mod-config-update-sc-eku | This-RFC   |
          +---------+-----------------------------+------------+

                                 Table 1

   IANA is also requested to register the following OIDs in the "SMI
   Security for PKIX Extended Key Purpose" registry [SMI-PKIX-PURPOSE].
   These OIDs are defined in Section 4.

         +=========+================================+============+
         | Decimal | Description                    | References |
         +=========+================================+============+
         | 41      | id-kp-configSigning            | This-RFC   |
         +---------+--------------------------------+------------+
         | 42      | id-kp-trustAnchorConfigSigning | This-RFC   |
         +---------+--------------------------------+------------+
         | 43      | id-kp-updatePackageSigning     | This-RFC   |
         +---------+--------------------------------+------------+
         | 44      | id-kp-safetyCommunication      | This-RFC   |
         +---------+--------------------------------+------------+

                                  Table 2

9.  Acknowledgments

   We would like to thank the authors of [RFC9336] and [RFC9509] for
   their excellent template.

   We also thank all reviewers of this document for their valuable
   feedback.

10.  References

10.1.  Normative References

   [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>.

   [RFC5280]  Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
              Housley, R., and W. Polk, "Internet X.509 Public Key
              Infrastructure Certificate and Certificate Revocation List
              (CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
              <https://www.rfc-editor.org/rfc/rfc5280>.

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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>.

   [X.680]    ITU-T, "Information Technology - Abstract Syntax Notation
              One (ASN.1): Specification of basic notation", ITU-T
              Recommendation X.680 , February 2021,
              <https://www.itu.int/rec/T-REC.X.680>.

   [X.690]    ITU-T, "Information Technology - ASN.1 encoding rules:
              Specification of Basic Encoding Rules (BER), Canonical
              Encoding Rules (CER) and Distinguished Encoding Rules
              (DER)", ITU-T Recommendation X.690 , February 2021,
              <https://www.itu.int/rec/T-REC.X.690>.

10.2.  Informative References

   [RFC5246]  Dierks, T. and E. Rescorla, "The Transport Layer Security
              (TLS) Protocol Version 1.2", RFC 5246,
              DOI 10.17487/RFC5246, August 2008,
              <https://www.rfc-editor.org/rfc/rfc5246>.

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/rfc/rfc8446>.

   [RFC9162]  Laurie, B., Messeri, E., and R. Stradling, "Certificate
              Transparency Version 2.0", RFC 9162, DOI 10.17487/RFC9162,
              December 2021, <https://www.rfc-editor.org/rfc/rfc9162>.

   [RFC9336]  Ito, T., Okubo, T., and S. Turner, "X.509 Certificate
              General-Purpose Extended Key Usage (EKU) for Document
              Signing", RFC 9336, DOI 10.17487/RFC9336, December 2022,
              <https://www.rfc-editor.org/rfc/rfc9336>.

   [RFC9509]  Reddy.K, T., Ekman, J., and D. Migault, "X.509 Certificate
              Extended Key Usage (EKU) for 5G Network Functions",
              RFC 9509, DOI 10.17487/RFC9509, March 2024,
              <https://www.rfc-editor.org/rfc/rfc9509>.

   [Directive-2016_797]
              European Parliament, Council of the European Union,
              "Directive 2016/797 - Interoperability of the rail system
              within the EU", May 2020,
              <https://eur-lex.europa.eu/eli/dir/2016/797/2020-05-28>.

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   [ERJU]     Europe's Rail Joint Undertaking, "Shared Cybersecurity
              Services Specification - SP-SEC-ServSpec - V1.0", February
              2025, <https://rail-research.europa.eu/wp-
              content/uploads/2025/03/ERJU-SP-Cybersecurity-
              Specifications-V1.0.zip>.

   [ERJU-web] Europe's Rail Joint Undertaking, "Europe’s Rail Joint
              Undertaking - System Pillar",
              <https://rail-research.europa.eu/system_pillar/>.

   [EU-CRA]   European Commission, "Proposal for a REGULATION OF THE
              EUROPEAN PARLIAMENT AND OF THE COUCIL on horizontal
              cybersecurity requirements for products with digital
              elements and amending Regulation (EU) 2019/1020",
              September 2022, <https://digital-
              strategy.ec.europa.eu/en/library/cyber-resilience-act>.

   [EU-STRATEGY]
              European Commission, "The EU's Cybersecurity Strategy for
              the Digital Decade", December 2020, <https://digital-
              strategy.ec.europa.eu/en/library/eus-cybersecurity-
              strategy-digital-decade-0>.

   [NIST_Glossary]
              NIST CSRC, "Directive (EU) 2022/2555 of the European
              Parliament and of the Council", n.d.,
              <https://csrc.nist.gov/glossary/term/safety>.

   [ISO.IEC.IEEE_12207]
              ISO/IEC/IEEE, "Systems and software engineering – Software
              life cycle processes", December 2024,
              <https://www.iso.org/standard/63712.html>.

   [NIS2]     European Commission, "Directive (EU) 2022/2555 of the
              European Parliament and of the Council", December 2024,
              <https://digital-strategy.ec.europa.eu/en/policies/
              nis2-directive>.

   [IEC.62443-4-2]
              IEC, "Security for industrial automation and control
              systems - Part 4-2: Technical security requirements for
              IACS components", IEC 62443-4-2:2019 , February 2019,
              <https://webstore.iec.ch/publication/34421>.

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   [IEC.62443-3-3]
              IEC, "Industrial communication networks - Network and
              system security - Part 3-3: System security requirements
              and security levels", IEC 62443-3-3:2013 , August 2013,
              <https://webstore.iec.ch/publication/7033>.

   [CE-marking]
              European Commission, "CE marking", n.d., <https://single-
              market-economy.ec.europa.eu/single-market/ce-marking_en>.

   [SMI-PKIX-PURPOSE]
              IANA, "SMI Security for PKIX Extended Key Purpose",
              <https://www.iana.org/assignments/smi-numbers/smi-
              numbers.xhtml#smi-numbers-1.3.6.1.5.5.7.3>.

   [SMI-PKIX-MOD]
              IANA, "SMI Security for PKIX Module Identifier",
              <https://www.iana.org/assignments/smi-numbers/smi-
              numbers.xhtml#smi-numbers-1.3.6.1.5.5.7.0>.

Appendix A.  ASN.1 Module

   The following module adheres to ASN.1 specifications [X.680] and
   [X.690].

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   <CODE BEGINS>

   Automation-EKU
     { iso(1) identified-organization(3) dod(6) internet(1)
       security(5) mechanisms(5) pkix(7) id-mod(0)
       id-mod-config-update-sc-eku (TBD1) }

   DEFINITIONS IMPLICIT TAGS ::=
   BEGIN

   -- OID Arc

   id-kp OBJECT IDENTIFIER ::=
     { iso(1) identified-organization(3) dod(6) internet(1)
       security(5) mechanisms(5) pkix(7) kp(3) }

   -- Extended Key Usage Values

   id-kp-configSigning            OBJECT IDENTIFIER ::= { id-kp 41 }
   id-kp-trustAnchorConfigSigning OBJECT IDENTIFIER ::= { id-kp 42 }
   id-kp-updatePackageSigning     OBJECT IDENTIFIER ::= { id-kp 43 }
   id-kp-safetyCommunication      OBJECT IDENTIFIER ::= { id-kp 44 }

   END

   <CODE ENDS>

Appendix B.  Use Cases

   These use cases are only for informational purposes.

   Automation hardware and software products strive to become more safe
   and secure by fulfilling mandatory, generic system requirements
   related to cyber security, e.g., driven by federal offices like the
   European Union Cyber Resilience Act [EU-CRA] governed by the European
   Commission and the High Representative of the Union for Foreign
   Affairs and Security Policy.  Automation products connected to the
   Internet would bear the so-called CE marking [CE-marking] to indicate
   they comply.  Such regulation was announced in the 2020 EU
   Cybersecurity Strategy [EU-STRATEGY], and complements other
   legislation in this area, like the NIS2 Framework, Directive on
   measures for a high common level of cybersecurity across the Union
   [NIS2].

   2020 EU Cybersecurity Strategy [EU-STRATEGY] suggests to implement
   and extend international standards such as the Security for
   industrial automation and control systems - Part 4-2: Technical

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   security requirements for IACS components [IEC.62443-4-2] (IACS
   refers to industrial automation and control system) and the
   Industrial communication networks - Network and system security -
   Part 3-3: System security requirements and security levels
   [IEC.62443-3-3].  Automation hardware and software products of
   diverse vendors that are connected on automation networks and the
   Internet can be used to build common automation solutions.
   Standardized attributes would allow transparency of security
   properties and interoperability for vendors in context of software
   and firmware updates, general-purpose configuration, trust anchor
   configuration, and safety communication.

   A concrete example for automation is a Rail Automation system.  The
   Europe's Rail web page [ERJU-web] states: "The System Pillar [ERJU]
   brings rail sector representatives under a single coordination body.
   To achieve this, the System Pillar will deliver a unified operational
   concept and a functional, safe and secure system architecture, with
   due consideration of cyber-security aspects, focused on the European
   railway network to which Directive 2016/797 [Directive-2016_797]
   applies (i.e. the heavy rail network) as well as associated
   specifications and/or standards."

Appendix C.  History of Changes

   [RFC Editor: Please remove this appendix in the release version of
   the document.]

   Changes from 07 -> 08:

   *  Updated Appendix B

   Changes from 06 -> 07:

   *  Moved Section 1.1 to the Appendix

   *  Addressed DISCUSS items from Mohamed Boucadair and Paul Wouters

   *  Addressed AD review comments from Paul Wouters and Orie Steele

   *  Fixed some minor issues

   *  Updated reference of EU Rail specification to V1.0

   Changes from 05 -> 06:

   *  Addressed AD review comments from Mike Bishop, Gorry Fairhurst,
      Andy Newton, Mohamed Boucadair, Erik Kline, and Eric Vyncke

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   Changes from 04 -> 05:

   *  Addressed SECDIR review comments from Carl Wallace

   Changes from 03 -> 04:

   *  Addressed Deb's AD review comments (see "AD Comments on draft-
      ietf-lamps-automation-keyusages")

   *  Added early allocated OIDs

   Changes from 02 -> 03:

   *  Rename id-kp-trustanchorSigning to id-kp-trustAnchorConfigSigning

   *  Rename id-kp-updateSigning to id-kp-updatePackageSigning

   *  Fixed some nits

   Changes from 01 -> 02:

   *  Updates Sections 3 and 6 addressing last call comments (see "WG
      Last Call for draft-ietf-lamps-automation-keyusages-01")

   Changes from 01 -> 02:

   *  Implemented the changes requested during WGLC

   Changes from 00 -> 01:

   *  Fixed some minor nids and wording issues

   draft-ietf-lamps-automation-keyusages version 00:

   *  Updated document and filename after WG adoption

   Changes from 00 -> 01:

   *  Updated last paragraph of Section 1 addressing WG adoption
      comments by Rich and Russ

   *  Updated name and OID of ASN.1 module

   draft-brockhaus-lamps-automation-keyusages version 00:

   *  Broadened the scope to general automation use case and use ERJU as
      an example.

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   *  Fixed some nits reported.

   draft-brockhaus-lamps-eu-rail-keyusages version 00:

   *  Initial version of the document following best practices from RFC
      9336 and RFC 9509

Contributors

   Szofia Fazekas-Zisch
   Siemens AG
   Breslauer Str. 5
   90766 Fuerth
   Germany
   Email: szofia.fazekas-zisch@siemens.com
   URI:   https://www.siemens.com

   Baptiste Fouques
   Alstom
   Email: baptiste.fouques@alstomgroup.com

   Daniel Gutierrez Orta
   CAF Signalling
   Email: daniel.gutierrez@cafsignalling.com

   Martin Weller
   Hitachi Rail
   Email: martin.weller@urbanandmainlines.com

   Nicolas Poyet
   SNCF
   Email: nicolas.poyet@sncf.fr

Authors' Addresses

   Hendrik Brockhaus
   Siemens
   Werner-von-Siemens-Strasse 1
   80333 Munich
   Germany
   Email: hendrik.brockhaus@siemens.com
   URI:   https://www.siemens.com

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   David Goltzsche
   Siemens Mobility
   Ackerstrasse 22
   38126 Braunschweig
   Germany
   Email: david.goltzsche@siemens.com
   URI:   https://www.mobility.siemens.com

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