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Post-Quantum Signature Algorithm Profile and Migration Considerations for the Resource Public Key Infrastructure (RPKI)
draft-yoshikawa-sidrops-pqc-rpki-00

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Author Tomoki Yoshikawa
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draft-yoshikawa-sidrops-pqc-rpki-00
SIDROPS                                                     T. Yoshikawa
Internet-Draft          Graduate School of Informatics, Kyoto University
Intended status: Standards Track                            19 June 2026
Expires: 21 December 2026

 Post-Quantum Signature Algorithm Profile and Migration Considerations
           for the Resource Public Key Infrastructure (RPKI)
                  draft-yoshikawa-sidrops-pqc-rpki-00

Abstract

   This document specifies an initial post-quantum signature algorithm
   profile and migration considerations for the Resource Public Key
   Infrastructure (RPKI).  It profiles ML-DSA-65 as the primary
   candidate for an RPKI next signature algorithm suite by reusing the
   ML-DSA algorithm identifiers and CMS conventions defined by LAMPS.
   It also describes how Certification Authorities, repository
   operators, and Relying Parties can evaluate and deploy a post-quantum
   suite while preserving the existing RPKI architecture and router-
   facing VRP/RTR model.

   This document profiles candidate post-quantum signature algorithms
   for RPKI certificates, CRLs, certification requests, and CMS signed
   objects.  It is written as input to SIDROPS discussion and does not
   update RFC 7935 in this revision.  It does not define a new RPKI
   object format, a new cryptographic primitive, a new repository
   synchronization protocol, or a new router protocol.

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/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 21 December 2026.

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Copyright Notice

   Copyright (c) 2026 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Requirements Language . . . . . . . . . . . . . . . . . . . .   3
   3.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   4.  Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . .   4
   5.  Design Goals  . . . . . . . . . . . . . . . . . . . . . . . .   4
   6.  Algorithm Profile . . . . . . . . . . . . . . . . . . . . . .   5
     6.1.  Current Suite . . . . . . . . . . . . . . . . . . . . . .   5
     6.2.  Primary Next Suite  . . . . . . . . . . . . . . . . . . .   5
     6.3.  Additional Candidate Suites . . . . . . . . . . . . . . .   5
     6.4.  Algorithm Selection Rationale . . . . . . . . . . . . . .   6
   7.  Resource Certificate and CRL Profile  . . . . . . . . . . . .   7
   8.  CMS Signed Object Profile . . . . . . . . . . . . . . . . . .   7
   9.  Manifests, ROAs, and Repository Processing  . . . . . . . . .   8
     9.1.  Implementation Evidence . . . . . . . . . . . . . . . . .   8
   10. Relying Party Behavior  . . . . . . . . . . . . . . . . . . .   9
   11. Migration Strategy  . . . . . . . . . . . . . . . . . . . . .   9
   12. Implementation Status . . . . . . . . . . . . . . . . . . . .  10
   13. Security Considerations . . . . . . . . . . . . . . . . . . .  11
   14. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  12
   15. Open Issues . . . . . . . . . . . . . . . . . . . . . . . . .  12
   16. Normative References  . . . . . . . . . . . . . . . . . . . .  13
   17. Informative References  . . . . . . . . . . . . . . . . . . .  15
   Appendix A.  Acknowledgements . . . . . . . . . . . . . . . . . .  16
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  16

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1.  Introduction

   The RPKI relies on digital signatures in resource certificates, CRLs,
   certification requests, and CMS signed objects such as manifests and
   Route Origin Authorizations (ROAs).  The deployed RPKI algorithm
   profile is based on RSA with SHA-256.  A Cryptographically Relevant
   Quantum Computer (CRQC) would invalidate the long-term security
   assumptions of RSA signatures.  RPKI therefore needs an algorithm
   migration path that can be tested before an emergency transition is
   required.

   The design goal of this document is conservative.  RPKI already has a
   well-defined architecture, repository system, validation procedure,
   and router interface.  This document keeps those layers intact.  PQC
   processing is introduced at the Certification Authority (CA),
   repository, CMS signed object, and Relying Party (RP) validation
   layers.  Routers that consume Validated ROA Payloads (VRPs) through
   the RPKI-Router Protocol (RTR) or local files are not expected to
   process PQC signatures directly.

   This revision is intended as a SIDROPS starting point.  It
   deliberately separates the protocol profile from the transition
   timetable and from the implementation evidence.  Where this document
   uses terms such as "candidate" or "evaluation", the text is
   identifying open engineering questions rather than declaring the
   final global RPKI migration plan.

2.  Requirements Language

   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 [BCP14] when, and only when, they appear in all capitals, as shown
   here.

3.  Terminology

   This document uses the terminology of the RPKI architecture
   [RFC6480], the resource certificate profile [RFC6487], the RPKI
   signed object template [RFC6488], the RPKI algorithm agility
   procedure [RFC6916], and the RPKI algorithm profile [RFC7935].

   Current Suite: The algorithm suite currently accepted by an RPKI
   implementation for production validation.  At the time of writing
   this is RSA-2048/SHA-256 as profiled by RFC 7935.

   Next Suite: A candidate algorithm suite that is implemented and
   tested before it becomes the Current Suite.

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   PQC Suite: A Next Suite whose signature algorithm is intended to
   remain secure against a CRQC.

   Corresponding Products: RPKI products issued under different
   algorithm suites that assert the same RPKI semantics.  For ROAs, this
   means the same set of VRPs, modulo local policy and trust anchor
   selection.

   Semantic Equivalence: A property of two validated RPKI outputs in
   which their routing semantics are identical.  For ROA-derived VRPs,
   the comparison keys are prefix, maxLength, origin AS, and validation
   source or trust anchor context.

   Parallel Publication: A migration technique in which a CA publishes
   corresponding products under both the Current Suite and the Next
   Suite for an extended interval.

   Composite Signature: A single signature algorithm construction that
   combines a PQC algorithm and a traditional algorithm at the
   cryptographic or encoding layer.  This document does not require
   composite signatures for the initial RPKI PQC suite.

4.  Scope

   This document applies to RPKI resource certificates, CRLs,
   certification requests, manifests [RFC9286], ROAs [RFC9582], and
   other CMS signed objects that reuse the RPKI signed object template.

   This document does not specify changes to BGPsec path signatures,
   ASPA, RSC, router certificates, RTR, TAL formats, RRDP [RFC8182],
   rsync, or the RPKI Certificate Policy.  These topics may require
   companion work after the basic certificate and CMS profile is
   interoperable.

5.  Design Goals

   The profile has the following goals.

   *  Preserve the existing RPKI architecture and repository model.

   *  Reuse existing LAMPS PKIX and CMS encodings for PQC algorithms.

   *  Avoid new RPKI object formats unless measurements show that simple
      signature substitution is infeasible.

   *  Keep routers as consumers of validated payloads, not PQC
      validators.

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   *  Support a prolonged Current Suite and Next Suite interval.

   *  Make downgrade, unsupported-algorithm, and semantic-divergence
      cases observable by RPs and operators.

   *  Keep measurement and interoperability evidence reproducible
      outside the protocol specification.

6.  Algorithm Profile

6.1.  Current Suite

   The Current Suite remains RSA PKCS #1 v1.5 with SHA-256 as specified
   by RFC 7935 until a separate transition timetable changes production
   RPKI policy.

6.2.  Primary Next Suite

   The primary PQC Next Suite candidate defined by this document is ML-
   DSA-65.

   This revision defines ML-DSA-65 as the primary candidate
   implementation profile.  It does not yet require production
   acceptance.  An implementation experiment SHOULD process id-ml-dsa-65
   in RPKI certificates and CRLs according to RFC 9881 and SHOULD report
   separately whether RFC 9882 CMS SignedData is supported.

   RPKI CAs participating in an isolated experiment MAY use ML-DSA-65
   for CA certificates, EE certificates, and CRLs.  They MUST NOT
   publish experimental objects into a production repository or use
   production keys or TALs.  CMS signed objects remain an
   interoperability work item in this revision.

6.3.  Additional Candidate Suites

   ML-DSA-87 MAY be implemented as a higher-security candidate,
   especially for experiments involving trust anchors or upper-tier CAs.
   This document does not require ML-DSA-87 for basic interoperability
   because it produces larger objects than ML-DSA-65.

   SLH-DSA-SHAKE-128s and SLH-DSA-SHAKE-192s MAY be implemented for
   cryptographic-diversity experiments.  They are not recommended as the
   initial default production RPKI suite in this version because their
   signature sizes and signing costs are substantially higher than ML-
   DSA in the available measurements.

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   Falcon/FN-DSA, MAYO, SNOVA, and HAWK are outside the mandatory path
   of this document.  They may be evaluated as research candidates, but
   they MUST NOT be treated as RPKI production algorithm suites by this
   document until stable PKIX and CMS profiles exist and are referenced
   by a future revision or separate document.

6.4.  Algorithm Selection Rationale

   ML-DSA-65 is selected as the primary candidate because it has an
   existing FIPS signature specification [FIPS204] and corresponding
   PKIX [RFC9881] and CMS [RFC9882] algorithm identifier specifications.
   It is not selected because it is always the smallest or fastest
   possible signature algorithm.

   ML-DSA-44 is retained as a measured comparison but is excluded from
   the primary profile because this document uses NIST Category 3 as a
   conservative minimum for the primary long-lived RPKI suite.  This is
   a profile policy choice, not evidence of an implementation failure,
   and SIDROPS may revisit it.

   ML-DSA-87, SLH-DSA-SHAKE-128s, and SLH-DSA-SHAKE-192s remain useful
   comparison points for security level, cryptographic diversity, and
   repository stress testing.  The SLH-DSA candidates have corresponding
   signature, PKIX, and CMS specifications [FIPS205] [RFC9909]
   [RFC9814].  Falcon/FN-DSA and other additional-signature candidates
   may be attractive for size or performance reasons, but they are
   outside the mandatory path of this revision until stable PKIX and CMS
   profiles and RPKI validator evidence are available.

   The first-order repository estimator gives Falcon-512, using a
   666-octet maximum signature size, a 1.5542 ratio to the RSA baseline
   and gives SNOVA-(24,5,4), using a 248-octet signature, a 1.2723
   ratio.  Both are much smaller than the estimated 4.0118 ratio for ML-
   DSA-65.  These ratios are synthetic estimates based on static
   parameter sizes, not local primitive or full-repository measurements:
   the corresponding backends were unavailable in the recorded run.
   They are outside the primary profile because stable PKIX and CMS
   profiles and validator evidence are absent, not because of repository
   size.  They should be reconsidered if their standardization and
   implementation maturity changes.

   Published RPKI analysis also identifies Falcon-512 as a compact and
   performance-oriented candidate [Doesburg2025].  This document treats
   that result as literature evidence; the accompanying evidence
   snapshot does not contain a confirmed local Falcon primitive
   benchmark.

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   Detailed measurements for key sizes, signature sizes, primitive
   timings, repository-size estimates, and validator probes are
   maintained outside this document by the experimental harness
   [pqc-rpki-lab].  Those values are implementation and environment
   dependent and are not protocol requirements.

7.  Resource Certificate and CRL Profile

   RPKI resource certificates and CRLs using ML-DSA MUST follow the
   certificate and CRL conventions for ML-DSA defined in RFC 9881.  In
   particular, AlgorithmIdentifier parameters for ML-DSA MUST be absent.

   When id-ml-dsa-65 or id-ml-dsa-87 appears in SubjectPublicKeyInfo,
   the subjectPublicKey BIT STRING contains the raw public key encoding
   defined by FIPS 204 and profiled by RFC 9881.

   For RPKI CA certificates, the keyUsage extension MUST remain
   consistent with the resource certificate profile.  A CA certificate
   that is used to issue certificates and CRLs requires keyCertSign and
   cRLSign.  An EE certificate used for an RPKI signed object requires
   digitalSignature and MUST NOT be used as a CA certificate.

   This document does not change the RPKI resource extension semantics,
   certificate policy OID, certificate path validation procedure,
   manifest processing rules, or CRL processing rules.

8.  CMS Signed Object Profile

   RPKI signed objects using ML-DSA MUST follow the CMS conventions for
   ML-DSA defined in [RFC9882] and the RPKI signed object template
   defined in [RFC6488], as updated by [RFC9589].

   The signatureAlgorithm field of SignerInfo MUST contain id-ml-dsa-65
   for the primary Next Suite.  AlgorithmIdentifier parameters MUST be
   absent.

   For ML-DSA-65, the digestAlgorithms field of SignedData and the
   digestAlgorithm field of SignerInfo MUST contain id-sha512.  The
   parameters field of that AlgorithmIdentifier MUST be absent.  The
   message-digest signed attribute MUST contain the SHA-512 digest of
   the eContent.  SHA-512 is selected from the algorithms permitted for
   ML-DSA-65 by [RFC9882] to provide one mandatory interoperable
   encoding for this RPKI suite.

   The signedAttrs element remains REQUIRED for RPKI signed objects.  In
   accordance with [RFC6488] as updated by [RFC9589], it MUST contain
   exactly one content-type attribute, one message-digest attribute, and
   one signing-time attribute.  The binary-signing-time attribute and

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   all other signed attributes MUST be absent.  In particular, the
   CMSAlgorithmProtection attribute suggested by the general CMS
   guidance in [RFC9882] MUST NOT be included because the RPKI signed
   object profile restricts signedAttrs to those three attributes.

   OpenSSL 3.6.2 generated ML-DSA certificates and CRLs but its CMS CLI
   rejected ML-DSA signing with CMS_add1_signer:no default digest.  The
   SHA-512 selection above follows [RFC9882]; the CLI failure remains an
   implementation and interoperability gap rather than an unspecified
   protocol value.

   The CMS eContentType and eContent for ROAs, manifests, and other RPKI
   signed objects are unchanged.  Validators MUST apply the object-
   specific validation rules after CMS signature validation exactly as
   they do for the Current Suite.

9.  Manifests, ROAs, and Repository Processing

9.1.  Implementation Evidence

   The accompanying implementation harness generated ML-DSA-65, ML-DSA-
   87, SLH-DSA-SHAKE-128s, and SLH-DSA-SHAKE-192s CA certificates, EE
   certificates, and CRLs using the OpenSSL 3.6.2 default provider.  The
   certificates included RFC 3779 IP address and AS resource extensions,
   RPKI certificate policy, Subject Information Access, basic
   constraints, and key usage.  Private keys were generated only in an
   automatically deleted temporary directory.

   The same OpenSSL installation did not generate ML-DSA CMS SignedData.
   Consequently, no RFC 6488 manifest or ROA was generated by the
   harness.  This is an implementation limitation, not evidence that the
   RFC profiles are incompatible.  Routinator, rpki-client, and FORT
   were not installed in the measurement environment, so validator
   acceptance is unconfirmed.

   The default run did not receive a real local RPKI cache.  Repository
   impact values in this revision remain synthetic or literature-
   calibrated estimates.

   This document does not define new payload encodings for manifests,
   ROAs, or CRLs.  Repository operators MAY publish Current Suite and
   Next Suite products in parallel during an algorithm transition.  A
   repository that publishes parallel products MUST ensure that
   manifests and CRLs are internally consistent within each suite.

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   During parallel publication, operators SHOULD provide a way to
   identify corresponding products across suites for measurement and
   debugging.  This identification MAY be derived from publication point
   structure, object names, CA hierarchy, or an implementation-specific
   mapping.  It is not a new on-wire RPKI object in this version.

10.  Relying Party Behavior

   An RP that implements this document MUST be configurable with an
   accepted algorithm policy.  The policy MUST be able to represent at
   least:

   *  Current Suite only;

   *  Current Suite plus Next Suite;

   *  Next Suite preferred with Current Suite fallback;

   *  Next Suite only.

   An RP MUST reject a certificate, CRL, or signed object whose
   signature algorithm is not in its configured policy.  The rejection
   reason SHOULD be reported distinctly from syntax errors, path
   validation failures, manifest failures, and object-specific semantic
   failures.

   An RP that validates both Current Suite and Next Suite products
   SHOULD perform semantic-equivalence checks for corresponding
   products.  For ROAs, this check compares the resulting VRP set by
   prefix, maxLength, origin AS, and trust anchor context.  If the
   Current Suite and Next Suite produce different routing semantics, the
   RP SHOULD emit telemetry and SHOULD NOT silently merge the divergent
   outputs.

   This document does not require routers to support PQC.  Routers
   receive validated payloads through RTR or local export formats.  The
   RP remains the cryptographic enforcement point.

11.  Migration Strategy

   The migration strategy follows the planned, multi-year model
   described in RFC 6916.  This document does not define an emergency
   migration.

   A deployment that follows this document is expected to proceed
   through the following phases.

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   1.  Implementation readiness: CAs and RPs add support for the Next
       Suite in non-production code paths.

   2.  Test repositories: operators publish PQC test repositories under
       test TALs.

   3.  Parallel publication: selected CAs publish corresponding products
       under the Current Suite and the Next Suite.

   4.  RP measurement: RPs validate both suites and report validation
       time, repository size, failure modes, and semantic equivalence.

   5.  PQC-preferred operation: RPs prefer the Next Suite while
       retaining the Current Suite for a limited period.

   6.  Classical retirement: a separate transition timetable defines the
       twilight date and withdrawal of the old suite.

   This document assumes the top-down migration constraint of RFC 6916
   for production deployment.  Experiments involving partial parent
   migration, partial child migration, or mixed unsupported validator
   deployment are useful for failure analysis, but they are not declared
   valid production transition states by this revision.

12.  Implementation Status

   This section records the status of known implementations of the
   protocol defined by this specification at the time of posting of this
   Internet-Draft, and is based on a proposal described in [RFC7942].
   It is intended to assist IETF discussion and is to be removed before
   publication as an RFC.

   An experimental repository, pqc-rpki-lab, was used to evaluate this
   proposal.  The implementation status at the time of this draft is:

   *  Static algorithm metadata: implemented.

   *  Primitive benchmark using existing libraries: implemented.

   *  Synthetic repository impact estimator: implemented.

   *  Local cache size collector: implemented.

   *  VRP semantic equivalence checker: implemented for CSV/JSON
      fixtures.

   *  Validator probes: implemented, but Routinator, rpki-client, and
      FORT were not installed in the test environment.

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   *  RFC-profiled PQC CA certificates, EE certificates, and CRLs:
      generated with OpenSSL 3.6.2 for ML-DSA and SLH-DSA.

   *  PQC CMS SignedData: unsupported by the tested OpenSSL CMS CLI,
      which returned CMS_add1_signer:no default digest.

   *  Manifest and ROA generation: not completed because PQC CMS signing
      and an existing payload generator were unavailable.

   *  Multi-validator interoperability using real PQC RPKI objects:
      future work.

   The highest-priority implementation gap is an RFC 9882-capable CMS
   path and an existing MFT/ROA payload generator.  The second highest-
   priority gap is independent validator behavior for complete objects.

13.  Security Considerations

   The purpose of this document is to reduce the risk that RPKI
   signatures become forgeable in the presence of a CRQC.  It does not
   solve CA compromise, repository compromise, operational misissuance,
   BGP policy mistakes, or route leaks.

   Downgrade attacks are a primary concern during a long transition.  An
   RP that supports both Current Suite and Next Suite products MUST make
   its algorithm acceptance policy explicit.  It MUST NOT silently
   accept a Current Suite product as equivalent to a missing or invalid
   Next Suite product when local policy requires the Next Suite.

   Parallel publication introduces the possibility of semantic
   divergence.  For example, the RSA branch and the PQC branch might
   contain different ROA payloads, stale manifests, or different CRL
   state.  Validators SHOULD detect and report these cases rather than
   silently selecting one branch without operator visibility.

   Larger public keys, signatures, certificates, CRLs, and CMS objects
   can increase repository transfer size, local cache size, manifest
   size, and validation time.  Implementations SHOULD enforce resource
   limits and telemetry for object size, number of objects, validation
   time, and memory use.  Operators SHOULD evaluate RRDP snapshot and
   delta sizes before large-scale deployment.

   ML-DSA uses randomized signing by default.  CA implementations and
   HSMs MUST use cryptographically appropriate randomness and SHOULD
   follow the operational guidance in RFC 9881 and RFC 9882.
   Deterministic signing is not preferred for platforms where side-
   channel or fault attacks are a concern.

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   Algorithm confusion is possible if AlgorithmIdentifier parameters,
   SignerInfo digestAlgorithm, CMS signed attributes, or certificate
   SubjectPublicKeyInfo encodings are inconsistently handled.
   Implementations MUST reject malformed AlgorithmIdentifier encodings
   and MUST follow the parameter rules of the referenced LAMPS
   specifications.

   Composite signatures may protect against failures in one component
   algorithm, but they also introduce additional encoding, policy, and
   interoperability complexity.  This document treats composite
   signatures as future work until the corresponding LAMPS
   specifications [I-D.ietf-lamps-pq-composite-sigs]
   [I-D.ietf-lamps-cms-composite-sigs] and RPKI-specific policy
   questions are stable.

14.  IANA Considerations

   This document requests no new IANA allocations in its current form.
   The ML-DSA and SLH-DSA algorithm identifiers are reused from existing
   PKIX and CMS specifications.  If a future revision defines an RPKI-
   specific algorithm-suite registry or new telemetry identifiers, this
   section will be updated.

15.  Open Issues

   The following issues require additional SIDROPS discussion and
   implementation evidence.  In particular, this draft should not
   strengthen ML-DSA-65 requirement language until complete RFC 6488 PQC
   objects are generated and major validator behavior is measured.

   *  Whether ML-DSA-65 should be mandatory-to-implement for RPs and
      CAs.

   *  Whether ML-DSA-87 is needed for trust anchors or upper-tier CAs.

   *  Whether SLH-DSA should remain only a diversity experiment.

   *  Whether composite signatures are needed for RPKI, or whether
      parallel publication is operationally sufficient.

   *  Whether Null Scheme-like signed-object reductions
      [I-D.doesburg-sidrops-nullscheme] should be considered separately
      from the initial signature-algorithm profile.

   *  How to define a transition timetable and readiness metrics for
      RPKI deployment.

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   *  Whether semantic-equivalence checking should be mandatory during
      the parallel-publication phase.

   *  How to handle PQC unsupported validators in mixed deployments.

   *  Whether TAK, ASPA, RSC, and BGPsec should be covered by this
      document or by separate companion documents.

   *  How RRDP snapshot and delta limits should be operationally
      assessed for larger objects.

   *  Whether any RPKI-specific object naming, repository layout, or
      manifest conventions are needed to map corresponding products
      across suites.

16.  Normative References

   [BCP14]    Best Current Practice 14,
              <https://www.rfc-editor.org/info/bcp14>.
              At the time of writing, this BCP comprises the following:

              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/info/rfc2119>.

              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/info/rfc8174>.

   [RFC6480]  Lepinski, M. and S. Kent, "An Infrastructure to Support
              Secure Internet Routing", RFC 6480, DOI 10.17487/RFC6480,
              February 2012, <https://www.rfc-editor.org/info/rfc6480>.

   [RFC6487]  Huston, G., Michaelson, G., and R. Loomans, "A Profile for
              X.509 PKIX Resource Certificates", RFC 6487,
              DOI 10.17487/RFC6487, February 2012,
              <https://www.rfc-editor.org/info/rfc6487>.

   [RFC6488]  Lepinski, M., Chi, A., and S. Kent, "Signed Object
              Template for the Resource Public Key Infrastructure
              (RPKI)", RFC 6488, DOI 10.17487/RFC6488, February 2012,
              <https://www.rfc-editor.org/info/rfc6488>.

   [RFC6916]  Gagliano, R., Kent, S., and S. Turner, "Algorithm Agility
              Procedure for the Resource Public Key Infrastructure
              (RPKI)", BCP 182, RFC 6916, DOI 10.17487/RFC6916, April
              2013, <https://www.rfc-editor.org/info/rfc6916>.

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   [RFC7935]  Huston, G. and G. Michaelson, Ed., "The Profile for
              Algorithms and Key Sizes for Use in the Resource Public
              Key Infrastructure", RFC 7935, DOI 10.17487/RFC7935,
              August 2016, <https://www.rfc-editor.org/info/rfc7935>.

   [RFC8182]  Bruijnzeels, T., Muravskiy, O., Weber, B., and R. Austein,
              "The RPKI Repository Delta Protocol (RRDP)", RFC 8182,
              DOI 10.17487/RFC8182, July 2017,
              <https://www.rfc-editor.org/info/rfc8182>.

   [RFC9286]  Austein, R., Huston, G., Kent, S., and M. Lepinski,
              "Manifests for the Resource Public Key Infrastructure
              (RPKI)", RFC 9286, DOI 10.17487/RFC9286, June 2022,
              <https://www.rfc-editor.org/info/rfc9286>.

   [RFC9582]  Snijders, J., Maddison, B., Lepinski, M., Kong, D., and S.
              Kent, "A Profile for Route Origin Authorizations (ROAs)",
              RFC 9582, DOI 10.17487/RFC9582, May 2024,
              <https://www.rfc-editor.org/info/rfc9582>.

   [RFC9589]  Snijders, J. and T. Harrison, "On the Use of the
              Cryptographic Message Syntax (CMS) Signing-Time Attribute
              in Resource Public Key Infrastructure (RPKI) Signed
              Objects", RFC 9589, DOI 10.17487/RFC9589, May 2024,
              <https://www.rfc-editor.org/info/rfc9589>.

   [RFC9814]  Housley, R., Fluhrer, S., Kampanakis, P., and B.
              Westerbaan, "Use of the SLH-DSA Signature Algorithm in the
              Cryptographic Message Syntax (CMS)", RFC 9814,
              DOI 10.17487/RFC9814, July 2025,
              <https://www.rfc-editor.org/info/rfc9814>.

   [RFC9881]  Massimo, J., Kampanakis, P., Turner, S., and B. E.
              Westerbaan, "Internet X.509 Public Key Infrastructure --
              Algorithm Identifiers for the Module-Lattice-Based Digital
              Signature Algorithm (ML-DSA)", RFC 9881,
              DOI 10.17487/RFC9881, October 2025,
              <https://www.rfc-editor.org/info/rfc9881>.

   [RFC9882]  Salter, B., Raine, A., and D. Van Geest, "Use of the ML-
              DSA Signature Algorithm in the Cryptographic Message
              Syntax (CMS)", RFC 9882, DOI 10.17487/RFC9882, October
              2025, <https://www.rfc-editor.org/info/rfc9882>.

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   [RFC9909]  Bashiri, K., Fluhrer, S., Gazdag, S., Van Geest, D., and
              S. Kousidis, "Internet X.509 Public Key Infrastructure --
              Algorithm Identifiers for the Stateless Hash-Based Digital
              Signature Algorithm (SLH-DSA)", RFC 9909,
              DOI 10.17487/RFC9909, December 2025,
              <https://www.rfc-editor.org/info/rfc9909>.

   [FIPS204]  National Institute of Standards and Technology, "Module-
              Lattice-Based Digital Signature Standard", FIPS 204,
              August 2024, <https://doi.org/10.6028/NIST.FIPS.204>.

   [FIPS205]  National Institute of Standards and Technology, "Stateless
              Hash-Based Digital Signature Standard", FIPS 205, August
              2024, <https://doi.org/10.6028/NIST.FIPS.205>.

17.  Informative References

   [RFC7942]  Sheffer, Y. and A. Farrel, "Improving Awareness of Running
              Code: The Implementation Status Section", BCP 205,
              RFC 7942, DOI 10.17487/RFC7942, July 2016,
              <https://www.rfc-editor.org/info/rfc7942>.

   [I-D.ietf-lamps-pq-composite-sigs]
              Ounsworth, M., Gray, J., Pala, M., Klaussner, J., and S.
              Fluhrer, "Composite Module-Lattice-Based Digital Signature
              Algorithm (ML-DSA) for use in X.509 Public Key
              Infrastructure", Work in Progress, Internet-Draft, draft-
              ietf-lamps-pq-composite-sigs-19, 21 April 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-lamps-
              pq-composite-sigs-19>.

   [I-D.ietf-lamps-cms-composite-sigs]
              Ounsworth, M., Gray, J., Klaussner, J., and D. Van Geest,
              "Composite Module-Lattice-Based Digital Signature
              Algorithm (ML-DSA) for use in Cryptographic Message Syntax
              (CMS)", Work in Progress, Internet-Draft, draft-ietf-
              lamps-cms-composite-sigs-05, 22 May 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-lamps-
              cms-composite-sigs-05>.

   [I-D.doesburg-sidrops-nullscheme]
              Doesburg, D., "Null Scheme for Signed Objects in the
              Resource Public Key Infrastructure (RPKI)", Work in
              Progress, Internet-Draft, draft-doesburg-sidrops-
              nullscheme-00, 5 October 2025,
              <https://datatracker.ietf.org/doc/html/draft-doesburg-
              sidrops-nullscheme-00>.

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   [Doesburg2025]
              Doesburg, D., "Post-Quantum Cryptography for the RPKI",
              June 2025, <https://www.sidnlabs.nl/en/news-and-blogs/
              thesis-pqc-for-the-rpki>.

   [pqc-rpki-lab]
              Yoshikawa, T., "pqc-rpki-lab experimental harness", June
              2026, <https://github.com/marokiki/pqc-rpki-
              lab/releases/tag/draft-yoshikawa-sidrops-pqc-rpki-00>.

Appendix A.  Acknowledgements

   The author thanks the SIDROPS and LAMPS communities for the
   specifications and implementation work that make this experiment
   possible.

Author's Address

   Tomoki Yoshikawa
   Graduate School of Informatics, Kyoto University
   Email: segre@marokiki.net

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