A Profile for Resource Public Key Infrastructure (RPKI) Canonical Cache Representation (CCR)
draft-ietf-sidrops-rpki-ccr-05

SIDROPS                                                      J. Snijders
Internet-Draft                                                       BSD
Intended status: Standards Track                               B. Bakker
Expires: 19 November 2026                                 T. Bruijnzeels
                                                                RIPE NCC
                                                              T. Buehler
                                                                 OpenBSD
                                                             18 May 2026

A Profile for Resource Public Key Infrastructure (RPKI) Canonical Cache
                          Representation (CCR)
                     draft-ietf-sidrops-rpki-ccr-05

Abstract

   This document specifies a Canonical Cache Representation (CCR)
   content type for use with the Resource Public Key Infrastructure
   (RPKI).  CCR is a DER-encoded data interchange format which can be
   used to represent various aspects of the state of a validated RPKI
   cache at a particular point in time.  The CCR profile is a compact
   and versatile format well-suited for applications such as audit
   trails, analytics pipelines, and validated payload dissemination.

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 19 November 2026.

Copyright Notice

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

Snijders, et al.        Expires 19 November 2026                [Page 1]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

   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
     1.1.  History . . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.2.  Requirements Language . . . . . . . . . . . . . . . . . .   3
   2.  The Canonical Cache Representation content type . . . . . . .   3
   3.  The Canonical Cache Representation content  . . . . . . . . .   4
     3.1.  version . . . . . . . . . . . . . . . . . . . . . . . . .   6
     3.2.  hashAlg . . . . . . . . . . . . . . . . . . . . . . . . .   6
     3.3.  producedAt  . . . . . . . . . . . . . . . . . . . . . . .   6
     3.4.  State aspect fields . . . . . . . . . . . . . . . . . . .   7
       3.4.1.  ManifestState . . . . . . . . . . . . . . . . . . . .   7
       3.4.2.  ROAPayloadState . . . . . . . . . . . . . . . . . . .   8
       3.4.3.  ASPAPayloadState  . . . . . . . . . . . . . . . . . .   9
       3.4.4.  TrustAnchorState  . . . . . . . . . . . . . . . . . .   9
       3.4.5.  RouterKeyState  . . . . . . . . . . . . . . . . . . .   9
   4.  Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . .  10
     4.1.  Constructing Consistent Views on Distributed Data . . . .  10
     4.2.  Data Collection . . . . . . . . . . . . . . . . . . . . .  10
   5.  Operational Considerations  . . . . . . . . . . . . . . . . .  10
     5.1.  CCR file integrity  . . . . . . . . . . . . . . . . . . .  11
     5.2.  Timing analysis . . . . . . . . . . . . . . . . . . . . .  11
     5.3.  Storage efficiency  . . . . . . . . . . . . . . . . . . .  11
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  11
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  12
     7.1.  SMI Security for S/MIME CMS Content Type
           (1.2.840.113549.1.9.16.1) . . . . . . . . . . . . . . . .  12
     7.2.  RPKI Repository Name Schemes  . . . . . . . . . . . . . .  12
     7.3.  SMI Security for S/MIME Module Identifier
           (1.2.840.113549.1.9.16.0) . . . . . . . . . . . . . . . .  12
     7.4.  Media Types . . . . . . . . . . . . . . . . . . . . . . .  13
       7.4.1.  Canonical Cache Representation Media Type . . . . . .  13
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  14
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  15
   Appendix A.  Acknowledgements . . . . . . . . . . . . . . . . . .  16
   Appendix B.  Example CCR  . . . . . . . . . . . . . . . . . . . .  17
   Appendix C.  Implementation status  . . . . . . . . . . . . . . .  19
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  19

Snijders, et al.        Expires 19 November 2026                [Page 2]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

1.  Introduction

   Resource Public Key Infrastructure (RPKI) operators often wish to
   analyze Certification Authority (CA) and Relying Party (RP) behavior
   by inspecting validation outcomes.  To this end, Canonical Cache
   Representation (CCR) was developed to capture and archive RPKI
   validation states in a standardized data representation.

   CCR offers a compact and versatile format well-suited for
   applications such as audit trails, analytics pipelines, and validated
   payload dissemination.  A validated cache contains all RPKI objects
   that the RP has verified to be valid according to the rules for
   validation (see [RFC6487], [RFC6488], [RFC9286]).  CCR is a data
   interchange format using Distinguished Encoding Rules (DER, [X.690])
   which can be used to represent various aspects of the state of a
   validated cache at a particular point in time in a reproducible
   manner.

   This document formally specifies the CCR content type for use with
   the RPKI and provides test vectors.

1.1.  History

   The format was initially designed to support comparative analysis of
   multiple RP instances using a variety of RPKI transport protocols
   ([RFC5781], [RFC8182], and [I-D.ietf-sidrops-rpki-erik-protocol]).

1.2.  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 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

2.  The Canonical Cache Representation content type

   The content of a CCR file is an instance of ContentInfo.

   The contentType for a CCR is defined as id-ct-
   rpkiCanonicalCacheRepresentation, with Object Identifier (OID)
   1.2.840.113549.1.9.16.1.54.

   The content field contains an instance of
   RpkiCanonicalCacheRepresentation.

Snijders, et al.        Expires 19 November 2026                [Page 3]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

3.  The Canonical Cache Representation content

   The content of a Canonical Cache Representation is formally defined
   as follows:

   RpkiCanonicalCacheRepresentation-2025
     { iso(1) member-body(2) us(840) rsadsi(113549)
       pkcs(1) pkcs9(9) smime(16) mod(0) id-mod-rpkiCCR-2025(TBD) }

   DEFINITIONS EXPLICIT TAGS ::=
   BEGIN

   IMPORTS
     CONTENT-TYPE, Digest, DigestAlgorithmIdentifier,
       SubjectKeyIdentifier
     FROM CryptographicMessageSyntax-2010 -- in [RFC6268]
       { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
         pkcs-9(9) smime(16) modules(0) id-mod-cms-2009(58) }

     ASID, ROAIPAddressFamily
     FROM RPKI-ROA-2023 -- in [RFC9582]
       { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
         pkcs9(9) smime(16) mod(0) id-mod-rpkiROA-2023(75) }

     CAS, PAS
     FROM RPKI-ASPA-2023 -- in [draft-ietf-sidrops-aspa-profile]
       { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
        pkcs-9(9) smime(16) modules(0) id-mod-rpki-aspa-2023(TBD) }

     CertificateSerialNumber, SubjectPublicKeyInfo
     FROM PKIX1Explicit-2009
       { iso(1) identified-organization(3) dod(6) internet(1)
         security(5) mechanisms(5) pkix(7) id-mod(0)
         id-mod-pkix1-explicit-02(51) }

     AccessDescription, KeyIdentifier
     FROM PKIX1Implicit-2009
       { iso(1) identified-organization(3) dod(6) internet(1)
         security(5) mechanisms(5) pkix(7) id-mod(0)
         id-mod-pkix1-implicit-02(59) }
     ;

   ContentInfo ::= SEQUENCE {
     contentType      CONTENT-TYPE.&id({ContentSet}),
     content      [0] EXPLICIT
                      CONTENT-TYPE.&Type({ContentSet}{@contentType}) }

   ContentSet CONTENT-TYPE ::= {

Snijders, et al.        Expires 19 November 2026                [Page 4]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

     ct-rpkiCanonicalCacheRepresentation, ... }

   ct-rpkiCanonicalCacheRepresentation CONTENT-TYPE ::=
     { TYPE RpkiCanonicalCacheRepresentation
       IDENTIFIED BY id-ct-rpkiCanonicalCacheRepresentation }

   id-ct-rpkiCanonicalCacheRepresentation OBJECT IDENTIFIER ::=
     { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
       pkcs-9(9) id-smime(16) id-ct(1) ccr(54) }

   RpkiCanonicalCacheRepresentation ::= SEQUENCE {
     version     [0] INTEGER DEFAULT 0,
     hashAlg         DigestAlgorithmIdentifier,
     producedAt      GeneralizedTime,
     mfts        [1] ManifestState OPTIONAL,
     vrps        [2] ROAPayloadState OPTIONAL,
     vaps        [3] ASPAPayloadState OPTIONAL,
     tas         [4] TrustAnchorState OPTIONAL,
     rks         [5] RouterKeyState OPTIONAL,
     ... }
     -- at least one of mfts, vrps, vaps, tas, or rks MUST be present
     ( WITH COMPONENTS { ..., mfts PRESENT } |
       WITH COMPONENTS { ..., vrps PRESENT } |
       WITH COMPONENTS { ..., vaps PRESENT } |
       WITH COMPONENTS { ..., tas PRESENT } |
       WITH COMPONENTS { ..., rks PRESENT } )

   ManifestState ::= SEQUENCE {
     mis               SEQUENCE OF ManifestInstance,
     mostRecentUpdate  GeneralizedTime,
     hash              Digest }

   ManifestInstance ::= SEQUENCE {
     hash              Digest,
     size              INTEGER (1000..MAX),
     aki               KeyIdentifier,
     manifestNumber    INTEGER (0..MAX),
     thisUpdate        GeneralizedTime,
     locations         SEQUENCE (SIZE(1..MAX)) OF AccessDescription,
     subordinates      SEQUENCE (SIZE(1..MAX)) OF SubjectKeyIdentifier
                         OPTIONAL }

   ROAPayloadState ::= SEQUENCE {
     rps               SEQUENCE OF ROAPayloadSet,
     hash              Digest }

   ROAPayloadSet ::= SEQUENCE {
     asID              ASID,

Snijders, et al.        Expires 19 November 2026                [Page 5]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

     ipAddrBlocks      SEQUENCE (SIZE(1..2)) OF ROAIPAddressFamily }

   ASPAPayloadState ::= SEQUENCE {
     aps               SEQUENCE OF ASPAPayloadSet,
     hash              Digest }

   ASPAPayloadSet ::= SEQUENCE {
     customerASID      CAS,
     providers         SEQUENCE (SIZE(1..MAX)) OF PAS }

   TrustAnchorState ::= SEQUENCE {
     skis              SEQUENCE (SIZE(1..MAX)) OF SubjectKeyIdentifier,
     hash              Digest }

   RouterKeyState ::= SEQUENCE {
     rksets            SEQUENCE OF RouterKeySet,
     hash              Digest }

   RouterKeySet ::= SEQUENCE {
     asID              ASID,
     routerKeys        SEQUENCE (SIZE(1..MAX)) OF RouterKey }

   RouterKey ::= SEQUENCE {
     ski               SubjectKeyIdentifier,
     spki              SubjectPublicKeyInfo }

   END

3.1.  version

   The version field contains the format version for the
   RpkiCanonicalCacheRepresentation structure, in this version of the
   specification it MUST be 0.

3.2.  hashAlg

   The hashAlg field specifies the algorithm used to construct the
   message digests.  This profile uses SHA-256 [SHS], therefore the OID
   MUST be 2.16.840.1.101.3.4.2.1 and the parameters field MUST be
   absent (Section 2 of [RFC5754]).

3.3.  producedAt

   The producedAt field contains a GeneralizedTime and indicates the
   moment in time the CCR was generated.  For the purposes of this
   section, CCR generation begins once the RP's fetching and validation
   operations are completed.

Snijders, et al.        Expires 19 November 2026                [Page 6]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

3.4.  State aspect fields

   Each CCR contains one or more fields representing particular aspects
   of the cache's state.  Implementers should note the ellipsis
   extension marker in the RpkiCanonicalCacheRepresentation ASN.1
   notation and anticipate future changes as new signed object types are
   standardized.

   Each state aspect generally consists of a sequence of details
   extracted from RPKI Objects of a specific type, along with a digest
   computed by hashing the aforementioned DER-encoded sequence, and
   optionally including some metadata.

3.4.1.  ManifestState

   An instance of ManifestState represents the set of valid, current
   Manifests ([RFC9286]) in the cache.  It contains three fields: mis,
   mostRecentUpdate, and hash.

3.4.1.1.  ManifestInstance

   The mis field contains a SEQUENCE of ManifestInstance.  There is one
   ManifestInstance for each current manifest.  A manifest is nominally
   current until the time specified in nextUpdate, or until a manifest
   is issued with a greater manifestNumber (see Section 4.2.1 of
   [RFC9286]), or until a new manifest is issued with a new filename per
   the process described in section 2 of [RFC9981].

   A ManifestInstance is a structure consisting of the following fields:

   hash  the hash of the represented DER-encoded manifest object

   size  the size of the represented DER-encoded manifest object

   aki  the manifest issuer's key identifier

   manifestNumber  the manifest number contained within the manifest's
      eContent field

   thisUpdate  the thisUpdate contained within the manifest's eContent
      field

   locations  a sequence of AccessDescription instances from the
      manifest's End-Entity certificate's Subject Information Access
      extension

   subordinates  a optional non-empty SEQUENCE of SubjectKeyIdentifier

Snijders, et al.        Expires 19 November 2026                [Page 7]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

   The subordinates field represents the keypairs associated with the
   set of non-revoked, non-expired, validly signed, certification
   authority (CA) resource certificates subordinate to the manifest
   issuer.  Each SubjectKeyIdentifier is the 160-bit SHA-1 hash of the
   value of the DER-encoded ASN.1 bit string of the resource
   certificate's Subject Public Key, as described in Section 4.8.2 of
   [RFC6487].  The sequence elements of the subordinates field MUST be
   sorted in ascending order by interpreting each SubjectKeyIdentifier
   value as an unsigned 160-bit integer and MUST be unique with respect
   to each other.

   The sequence elements in the mis field MUST be sorted in ascending
   order by hash value contained in each instance of ManifestInstance
   and MUST be unique with respect to the other instances of
   ManifestInstance.

3.4.1.2.  mostRecentUpdate

   The mostRecentUpdate is a metadata field which contains the most
   recent thisUpdate amongst all current manifests represented by the
   ManifestInstance structures.  If the mis field contains an empty
   sequence, the mostRecentUpdate MUST be set to the POSIX Epoch
   ("19700101000000Z").

   The above and the requirements in Section 6.3 of [RFC9286] imply that
   mostRecentUpdate MUST precede or be equal to producedAt
   (Section 3.3).

3.4.1.3.  hash

   The hash field contains a message digest computed using the mis value
   (encoded in DER format) as input message.

3.4.2.  ROAPayloadState

   An instance of ROAPayloadState contains a field named rps which
   represents the current set of Validated ROA Payloads (Section 2 of
   [RFC6811]) encoded as a SEQUENCE of ROAPayloadSet instances ordered
   by ascending asID.

   The ROAPayloadSet structure is modeled after the
   RouteOriginAttestation (Section 4 of [RFC9582]).  The asID value in
   each instance of ROAPayloadSet MUST be unique with respect to other
   instances of ROAPayloadSet.  The contents of the ipAddrBlocks field
   MUST appear in canonical form and ordered as defined in Section 4.3.3
   of [RFC9582].

Snijders, et al.        Expires 19 November 2026                [Page 8]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

   The hash field contains a message digest computed using the rps value
   (encoded in DER format) as input message.

3.4.3.  ASPAPayloadState

   An instance of ASPAPayloadState contains an aps field which
   represents the current set of deduplicated and merged ASPA payloads
   ([I-D.ietf-sidrops-aspa-profile]) value encoded as a SEQUENCE of
   ASPAPayloadSet instances ordered by ascending customerASID.  The
   customerASID value in each instance of ASPAPayloadSet MUST be unique
   with respect to other instances of ASPAPayloadSet.

   The ASPAPayloadSet structure is modeled after the ProviderASSet
   (Section 3.3 of [I-D.ietf-sidrops-aspa-profile]).  The elements of
   providers MUST be ordered in ascending numerical order and MUST be
   unique (with respect to the other elements of providers).  A PAS
   value of 0 can only be encoded in the providers field as a single
   item list, i.e., an element for AS 0 MUST NOT appear alongside any
   other elements.

   The hash field contains a message digest computed using the aps value
   (encoded in DER format) as input message.

3.4.4.  TrustAnchorState

   An instance of TrustAnchorState represents the set of valid Trust
   Anchor (TA) Certification Authority (CA) resource certificates used
   by the relying party when producing the CCR.

   Each SubjectKeyIdentifier is the 160-bit SHA-1 hash of the value of
   the DER-encoded ASN.1 bit string of the TA's Subject Public Key, as
   described in Section 4.8.2 of [RFC6487].  The skis field contains a
   sequence of Subject Key Identifiers (SKI) sorted in ascending order
   by interpreting the SKI value as an unsigned 160-bit integer.

   The hash field contains a message digest computed using the skis
   value (encoded in DER format) as input message.

3.4.5.  RouterKeyState

   An instance of RouterKeyState contains an rksets field which
   represents the current set of valid BGPsec Router Keys [RFC8205]
   encoded as a SEQUENCE of RouterKeySet instances.  The asID value in
   each instance of RouterKeySet MUST be unique with respect to other
   instances of RouterKeySet.  Instances of RouterKeySet are sorted by
   ascending value of asID.  Instances of RouterKey are sorted by
   ascending value of ski by interpreting the SKI value as an unsigned
   160-bit integer.

Snijders, et al.        Expires 19 November 2026                [Page 9]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

   The hash field contains a message digest computed using the rks value
   (encoded in DER format) as input message.

4.  Use Cases

   This section describes a number of applications for the CCR format
   across different contexts.

4.1.  Constructing Consistent Views on Distributed Data

   This section describes a use case for CCRs in the context of
   distributed systems.

   Assuming CAs issue Manifests in accordance with Section 5 of
   [RFC9286], a ManifestInstance can be considered a state-based
   Conflict-free Replicated Data Type ([CRDT]), meaning that
   ManifestInstance sets contain sufficient information to form a
   monotonic semilattice.

   The implication is that ManifestState instances from multiple CCRs
   produced by multiple different RPs at different times can safely be
   merged in order to construct an internally consistent view of the
   RPKI distributed database.

   The reconciled merge result can be useful, for example, as a backend
   for Erik Synchronization relays
   ([I-D.ietf-sidrops-rpki-erik-protocol]) which execute separate
   validation processes for different Trust Anchors and varying maximum
   certificate chain depths.

4.2.  Data Collection

   Operators have an interest in determining how the global RPKI is
   viewed from the perspectives of several different locations around
   the Internet.  As CCR allows for point-in-time capture and later
   reconstruction and analysis, it found use in multi-perspective
   collector methods such as described RPKISPOOL
   [I-D.snijders-rpkispool-format].

   An example of a large-scale CCR-based RPKI data archival project is
   [RPKIViews].

5.  Operational Considerations

   This section covers operational considerations.

Snijders, et al.        Expires 19 November 2026               [Page 10]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

5.1.  CCR file integrity

   The integrity of a CCR file can be checked by confirming whether the
   hash value embedded inside each state aspect matches the computed
   hash value of the respective state aspect payload structure.  Readers
   MUST verify the integrity of CCR files and stop further processing on
   failure.

5.2.  Timing analysis

   The producedAt timestamp is not necessarily the current time used by
   the RP for the purposes of validating the RPKI content.  In practice,
   most RPs interleave fetching and validation operations, with
   validation occurring with respect to whatever the time happens to be
   at that point (i.e., wall clock time).  This means that it is
   possible for a CCR to include information that would have been
   excluded if validated at the time indicated by the producedAt
   timestamp.

   If the CCR is produced right after all relevant repository content
   was received and validated by an RP, then comparing the ManifestState
   mostRecentUpdate timestamp (Section 3.4.1.2) value with the CCR
   producedAt timestamp (Section 3.3) might help offer insight into the
   timing and propagation delays of the RPKI ecosystem.

5.3.  Storage efficiency

   CCRs compress very well due to its data layout characteristics: the
   content contains repetitive sequences, does not contain high entropy
   data such as public keys, and is consistently ordered.  Readers and
   writers of CCR data are RECOMMENDED to support data compression using
   Gzip ([RFC1952]) in context of durable storage.

6.  Security Considerations

   The CCR format utilizes a structure that can store information about
   the state of a given RPKI cache at a particular moment in time.  The
   fields defined in this specification are of a descriptive nature and
   provide information that is useful to facilitate the analysis of RPKI
   data.  As such, these fields do not in themselves create additional
   security risks, since the fields are not used to induce any
   particular behavior by the recipient application.

   Readers MUST check contextual bounds on all fields appropriately and
   stop further processing on failure.  E.g., the maxLength element in a
   ROAIPAddress cannot contain an integer smaller than the length of the
   accompanying prefix, the manifestNumber field is cannot be longer
   than 20 octets, etc.

Snijders, et al.        Expires 19 November 2026               [Page 11]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

   The CCR format contains no executable code, and it does not define
   any extensible areas that could be used to store such code.

   CCRs are not signed objects.  RPKI information is normally public and
   does not call for confidentiality protection.  Ascertaining the
   provenance (and thus authenticity) of any given CCR is out-of-scope
   for this document.

7.  IANA Considerations

7.1.  SMI Security for S/MIME CMS Content Type (1.2.840.113549.1.9.16.1)

   IANA has allocated the following in the "SMI Security for S/MIME CMS
   Content Type (1.2.840.113549.1.9.16.1)" registry:

     +=========+==================================+==================+
     | Decimal | Description                      | References       |
     +=========+==================================+==================+
     | 54      | id-ct-                           | draft-ietf-      |
     |         | rpkiCanonicalCacheRepresentation | sidrops-rpki-ccr |
     +---------+----------------------------------+------------------+

                                  Table 1

7.2.  RPKI Repository Name Schemes

   IANA is requested to add the Canonical Cache Representation file
   extension to the "RPKI Repository Name Schemes" registry [RFC6481] as
   follows:

       +===========+=================+=============================+
       | Filename  | RPKI Object     | Reference                   |
       | Extension |                 |                             |
       +===========+=================+=============================+
       | .ccr      | Canonical Cache | draft-ietf-sidrops-rpki-ccr |
       |           | Representation  |                             |
       +-----------+-----------------+-----------------------------+

                                  Table 2

7.3.  SMI Security for S/MIME Module Identifier
      (1.2.840.113549.1.9.16.0)

   IANA is requested to allocate the following in the "SMI Security for
   S/MIME Module Identifier (1.2.840.113549.1.9.16.0)" registry:

Snijders, et al.        Expires 19 November 2026               [Page 12]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

      +=========+=====================+=============================+
      | Decimal | Description         | References                  |
      +=========+=====================+=============================+
      | TBD     | id-mod-rpkiCCR-2025 | draft-ietf-sidrops-rpki-ccr |
      +---------+---------------------+-----------------------------+

                                  Table 3

7.4.  Media Types

   IANA is requested to register the media types "application/rpki-ccr"
   and "application/rpki-ccr+gzip" in the "Media Types" registry as
   follows:

7.4.1.  Canonical Cache Representation Media Type

   Type name:  application
   Subtype name:  rpki-ccr
   Required parameters:  N/A
   Optional parameters:  N/A
   Encoding considerations:  binary
   Security considerations:  This media type contains no active content.
   Interoperability considerations:  N/A
   Published specification:  draft-ietf-sidrops-rpki-ccr
   Applications that use this media type:  RPKI operators
   Fragment identifier considerations:  N/A
   Additional information:
                            Content:  This media type is a RPKI
         Canonical Cache Representation object, as defined in draft-
         ietf-sidrops-rpki-ccr.
                            Magic number(s):  N/A
                            File extension(s):  .ccr
                            Macintosh file type code(s):  N/A
   Person & email address to contact for further information:  Job
      Snijders (job@bsd.nl)
   Intended usage:  COMMON
   Restrictions on usage:  N/A
   Author:  Job Snijders (job@bsd.nl)
   Change controller:  IETF

   Type name:  application
   Subtype name:  rpki-ccr+gzip
   Content:  This media type is a Gzip compressed RPKI Canonical Cache
      Representation object, as defined in draft-ietf-sidrops-rpki-ccr.
   Magic number(s):  N/A
   File extension(s):  .ccr.gz
   References:  RFC1952, RFC6713

Snijders, et al.        Expires 19 November 2026               [Page 13]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

   Encoding considerations:  gzip is a binary encoding

8.  References

8.1.  Normative References

   [I-D.ietf-sidrops-aspa-profile]
              Snijders, J., Azimov, A., Uskov, E., Bush, R., Housley,
              R., and B. Maddison, "A Profile for Autonomous System
              Provider Authorization", Work in Progress, Internet-Draft,
              draft-ietf-sidrops-aspa-profile-26, 19 April 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-sidrops-
              aspa-profile-26>.

   [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/info/rfc2119>.

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

   [RFC6481]  Huston, G., Loomans, R., and G. Michaelson, "A Profile for
              Resource Certificate Repository Structure", RFC 6481,
              DOI 10.17487/RFC6481, February 2012,
              <https://www.rfc-editor.org/info/rfc6481>.

   [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>.

   [RFC6811]  Mohapatra, P., Scudder, J., Ward, D., Bush, R., and R.
              Austein, "BGP Prefix Origin Validation", RFC 6811,
              DOI 10.17487/RFC6811, January 2013,
              <https://www.rfc-editor.org/info/rfc6811>.

   [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/info/rfc8174>.

Snijders, et al.        Expires 19 November 2026               [Page 14]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

   [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>.

   [RFC9981]  Harrison, T., Michaelson, G., and J. Snijders, "Resource
              Public Key Infrastructure (RPKI) Manifest Number
              Handling", May 2026,
              <https://www.rfc-editor.org/info/rfc9981>.

   [SHS]      National Institute of Standards and Technology, "Secure
              Hash Standard", March 2012,
              <https://csrc.nist.gov/publications/fips/fips180-4/fips-
              180-4.pdf>.

   [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, ISO/IEC 8825-1:2021,
              February 2021,
              <https://www.itu.int/rec/T-REC-X.690-202102-I/en>.

8.2.  Informative References

   [CRDT]     Shapiro, M., Preguiça, N., Baquero, C., and M. Zawirski,
              "Conflict-free Replicated Data Types", INRIA RR-7687, July
              2011, <https://inria.hal.science/inria-00609399>.

   [I-D.ietf-sidrops-rpki-erik-protocol]
              Snijders, J., Bruijnzeels, T., Harrison, T., and W. Ohgai,
              "The Erik Synchronization Protocol for use with the
              Resource Public Key Infrastructure (RPKI)", Work in
              Progress, Internet-Draft, draft-ietf-sidrops-rpki-erik-
              protocol-04, 17 March 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-sidrops-
              rpki-erik-protocol-04>.

Snijders, et al.        Expires 19 November 2026               [Page 15]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

   [I-D.snijders-rpkispool-format]
              Snijders, J. and F. Vompe, "The RPKISPOOL Format for
              Materializing Resource Public Key Infrastructure (RPKI)
              Data", Work in Progress, Internet-Draft, draft-snijders-
              rpkispool-format-00, 2 March 2026,
              <https://datatracker.ietf.org/doc/html/draft-snijders-
              rpkispool-format-00>.

   [RFC1952]  Deutsch, P., "GZIP file format specification version 4.3",
              RFC 1952, DOI 10.17487/RFC1952, May 1996,
              <https://www.rfc-editor.org/info/rfc1952>.

   [RFC5781]  Weiler, S., Ward, D., and R. Housley, "The rsync URI
              Scheme", RFC 5781, DOI 10.17487/RFC5781, February 2010,
              <https://www.rfc-editor.org/info/rfc5781>.

   [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>.

   [RFC8205]  Lepinski, M., Ed. and K. Sriram, Ed., "BGPsec Protocol
              Specification", RFC 8205, DOI 10.17487/RFC8205, September
              2017, <https://www.rfc-editor.org/info/rfc8205>.

   [rpki-client]
              Jeker, C., Dzonsons, K., Buehler, T., and J. Snijders,
              "rpki-client", December 2025,
              <https://www.rpki-client.org/>.

   [rpki-commons]
              NCC, R., "rpki-commons", April 2026,
              <https://github.com/RIPE-NCC/rpki-commons>.

   [rpkitouch]
              Snijders, J., "rpki-client", December 2025,
              <https://www.github.com/job/rpkitouch>.

   [RPKIViews]
              Snijders, J., "The RPKIViews Project", April 2026,
              <https://www.rpkiviews.org/>.

Appendix A.  Acknowledgements

   The authors wish to thank Russ Housley, Luuk Hendriks, Fedor Vompe,
   and Tom Harrison for their generous feedback on this specification.

Snijders, et al.        Expires 19 November 2026               [Page 16]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

Appendix B.  Example CCR

   The below is a Base64-encoded example CCR object.  For a more
   elaborate example based on the global RPKI, see the URL in
   Appendix C.

   MIIF9AYLKoZIhvcNAQkQATagggXjMIIF3zALBglghkgBZQMEAgEYDzIwMjYwNTE1MDAwM
   DEwWqGCAtUwggLRMIICmjCBmAQgKF60zgHHRNmQSUXcsAcAPB2cB7kvToWUF60GADJuG5
   ECAgPpBBSi3wQv6LAAYxHolIUawRQRMHtgQwICEyEYDzIwMjYwNTE1MDAwMDA5WjBFMEM
   GCCsGAQUFBzALhjdyc3luYzovL2V4YW1wbGUubmV0L2NhNC9Ra3NiUVpNQzdZV3NOclJF
   dDRsNGRXQVExc0UubWZ0MIGYBCA8fzi045g3wS16tiKY4MxriwOP0eQx7JM3IKzL/1D/j
   wICB/gEFPrL0CykfjvZZm/L2COzfe3QvO4AAgICAxgPMjAyNjA1MTUwMDAwMDdaMEUwQw
   YIKwYBBQUHMAuGN3JzeW5jOi8vZXhhbXBsZS5uZXQvY2EyL3owbnpWUzdTT0JfOXk2dGF
   wSGs3LVl1S2ttOC5tZnQwgZgEIL3nuZvothSocx8JXZLAtiF9FpVXBx1btwfKgDJ5Pv16
   AgIPmwQU5zFepRXXwgU4aBJJ0+MNZ3cWJYUCAgUIGA8yMDI2MDUxNTAwMDAwOFowRTBDB
   ggrBgEFBQcwC4Y3cnN5bmM6Ly9leGFtcGxlLm5ldC9jYTMvc2JoRnp6NHdUcXNGbzJOVl
   JNOG1XZnNQQktRLm1mdDCBxgQg48JkKNPGfzSWjkALB4rFbaktXGSFaAV5qj0gj7zCCFY
   CAgbBBBQl+Mz878BG2NzQD8DkROCqe3kPlgICAQEYDzIwMjYwNTE1MDAwMDA2WjBFMEMG
   CCsGAQUFBzALhjdyc3luYzovL2V4YW1wbGUubmV0L2NhMS9PYVZVT0lEU2FMelViZWl6N
   lZQb2dYeHNLNW8ubWZ0MCwEFKLfBC/osABjEeiUhRrBFBEwe2BDBBTnMV6lFdfCBThoEk
   nT4w1ndxYlhRgPMjAyNjA1MTUwMDAwMDlaBCBjjUCOSmIWv8DNHb9zxwi1k6YgLC4hpk4
   aph0pqidsEqKBoTCBnjB6MBUCAQAwEDAOBAIAATAIMAYDBADAAAIwLQIDAQAAMCYwEQQC
   AAEwCzAJAwQAxjNkAgEcMBEEAgACMAswCQMHACABDQgAADAYAgMBAA4wETAPBAIAAjAJM
   AcDBQA//wAAMBgCAwEADzARMA8EAgACMAkwBwMFAD//AAAEIJgOVAZ7JE7OekW9qMlKUN
   jkGdzgod7Fcobph5AfXVkCo1MwUTAtMAwCAwD7/zAFAgMA+/AwEQIDAQAAMAoCAwEABAI
   DAQAIMAoCAwEADjADAgEABCAnN98QySyKCzUlPnxJJT5iGrRQCLLbvCDdt4esCyUUU6RS
   MFAwLAQUJfjM/O/ARtjc0A/A5ETgqnt5D5YEFPrL0CykfjvZZm/L2COzfe3QvO4ABCAO5
   kLEyVH4bH17eMAESlf9gYYe1a99AfW+q44/jdcDEaWCAZcwggGTMIIBbTCB7gIDAP5jMI
   HmMHEEFIjF3ilaMnbWnpu3RpvUbvly3jKsMFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgA
   E64mxtNmdKd1bxIjgWrGJutr11LDeA56L8cc1NLL/WW9RZ+rbi+G4rFSvfrEjxzRPt6tc
   NWpgEINq7tOR7J5dAjBxBBS+FudOEPS98/jCYYsCSpRX37+J+jBZMBMGByqGSM49AgEGC
   CqGSM49AwEHA0IABCo6kzaMUiyt1JyzDY9gHTf+bJOUiE52FiuXvyXmypSTxRcZgazl1k
   Moo0UARRbrOxrSyyGQWIKeCv7vKNvw+IowegIDAQAPMHMwcQQURgK2IbAXaB5h7h9KXvw
   dAsO0bywwWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAAThe3r51EOGOYfRBWZeVQ+d0l5f
   LOUxyxyjpaSuMF/o2hfqBhqERKAKbrvGQErhnGG8JlEVYvGofxyBP8+C+X3jBCCfSt7Zy
   MVIWZ18hjoqeDkmVGKSbWfe4VJZrVgJs5v/FA==

   It decodes as follows:

   =============== NOTE: '\' line wrapping per RFC 8792 ================

   File:                   example.ccr
   Hash identifier:        8mdCrklrbLHKzDVr5fFbsGK4fyJsArmsGeLShZhRyio=
   CCR produced at:        Fri 15 May 2026 00:00:10 +0000
   Manifest state hash:    Y41AjkpiFr/AzR2/c8cItZOmICwuIaZOGqYdKaonbBI=
   Manifest last update:   Fri 15 May 2026 00:00:09 +0000
   Manifest instances:
                           hash:48JkKNPGfzSWjkALB4rFbaktXGSFaAV5qj0gj7z\

Snijders, et al.        Expires 19 November 2026               [Page 17]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

   CCFY= size:1729 aki:25F8CCFCEFC046D8DCD00FC0E444E0AA7B790F96 seqnum:\
   0101 thisupdate:1778803206 sia:rsync://example.net/ca1/OaVUOIDSaLzUb\
   eiz6VPogXxsK5o.mft subordinates:A2DF042FE8B0006311E894851AC11411307B\
   6043,E7315EA515D7C20538681249D3E30D6777162585
                           hash:KF60zgHHRNmQSUXcsAcAPB2cB7kvToWUF60GADJ\
   uG5E= size:1001 aki:A2DF042FE8B0006311E894851AC11411307B6043 seqnum:\
   1321 thisupdate:1778803209 sia:rsync://example.net/ca4/QksbQZMC7YWsN\
   rREt4l4dWAQ1sE.mft
                           hash:vee5m+i2FKhzHwldksC2IX0WlVcHHVu3B8qAMnk\
   +/Xo= size:3995 aki:E7315EA515D7C20538681249D3E30D6777162585 seqnum:\
   0508 thisupdate:1778803208 sia:rsync://example.net/ca3/sbhFzz4wTqsFo\
   2NVRM8mWfsPBKQ.mft
                           hash:PH84tOOYN8EterYimODMa4sDj9HkMeyTNyCsy/9\
   Q/48= size:2040 aki:FACBD02CA47E3BD9666FCBD823B37DEDD0BCEE00 seqnum:\
   0203 thisupdate:1778803207 sia:rsync://example.net/ca2/z0nzVS7SOB_9y\
   6tapHk7-YuKkm8.mft
   ROA payload state hash: mA5UBnskTs56Rb2oyUpQ2OQZ3OCh3sVyhumHkB9dWQI=
   ROA payload entries:
                           192.0.2.0/24 AS 0
                           198.51.100.0/24-28 AS 65536
                           2001:d08::/48 AS 65536
                           3fff::/32 AS 65550
                           3fff::/32 AS 65551
   ASPA payload state hash:JzffEMksigs1JT58SSU+Yhq0UAiy27wg3beHrAslFFM=
   ASPA payload entries:
                           customer: 64511 providers: 64496
                           customer: 65536 providers: 65540, 65544
                           customer: 65550 providers: 0
   Trust anchor state hash:DuZCxMlR+Gx9e3jABEpX/YGGHtWvfQH1vquOP43XAxE=
   Trust anchor keyids:    25F8CCFCEFC046D8DCD00FC0E444E0AA7B790F96, FA\
   CBD02CA47E3BD9666FCBD823B37DEDD0BCEE00
   Router key state hash:  n0re2cjFSFmdfIY6Kng5JlRikm1n3uFSWa1YCbOb/xQ=
   Router keys:
                           asid:65123 ski:88C5DE295A3276D69E9BB7469BD46\
   EF972DE32AC pubkey:MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE64mxtNmdKd1bx\
   IjgWrGJutr11LDeA56L8cc1NLL/WW9RZ+rbi+G4rFSvfrEjxzRPt6tcNWpgEINq7tOR7\
   J5dAg==
                           asid:65123 ski:BE16E74E10F4BDF3F8C2618B024A9\
   457DFBF89FA pubkey:MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEKjqTNoxSLK3Un\
   LMNj2AdN/5sk5SITnYWK5e/JebKlJPFFxmBrOXWQyijRQBFFus7GtLLIZBYgp4K/u8o2\
   /D4ig==
                           asid:65551 ski:4602B621B017681E61EE1F4A5EFC1\
   D02C3B46F2C pubkey:MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE4Xt6+dRDhjmH0\
   QVmXlUPndJeXyzlMcsco6WkrjBf6NoX6gYahESgCm67xkBK4ZxhvCZRFWLxqH8cgT/Pg\
   vl94w==
   Validation:             N/A

Snijders, et al.        Expires 19 November 2026               [Page 18]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

Appendix C.  Implementation status

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

   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 RFC 7942.
   The description of implementations in this section is intended to
   assist the IETF in its decision processes in progressing drafts to
   RFCs.  Please note that the listing of any individual implementation
   here does not imply endorsement by the IETF.  Furthermore, no effort
   has been spent to verify the information presented here that was
   supplied by IETF contributors.  This is not intended as, and must not
   be construed to be, a catalog of available implementations or their
   features.  Readers are advised to note that other implementations may
   exist.

   According to RFC 7942, "this will allow reviewers and working groups
   to assign due consideration to documents that have the benefit of
   running code, which may serve as evidence of valuable experimentation
   and feedback that have made the implemented protocols more mature.
   It is up to the individual working groups to use this information as
   they see fit".

   *  Example .ccr files were created by Job Snijders.  A current
      example CCR (regenerated every few minutes) is available here:
      https://console.rpki-client.org/rpki.ccr

   *  A CCR serializer and deserializer implementation based on
      [rpki-client] was provided by Job Snijders and Theo Buehler.

   *  Another CCR serializer, deserializer, and CRDT effector
      implementation based on [rpkitouch] was provided by Job Snijders.

   *  A CCR encoding and decoding implementation in Java library
      [rpki-commons] was provided by RIPE NCC.

Authors' Addresses

   Job Snijders
   BSD Software Development
   Amsterdam
   Netherlands
   Email: job@bsd.nl
   URI:   https://www.bsd.nl

Snijders, et al.        Expires 19 November 2026               [Page 19]
Internet-Draft     RPKI Canonical Cache Representation          May 2026

   Bart Bakker
   RIPE NCC
   Netherlands
   Email: bbakker@ripe.net

   Tim Bruijnzeels
   RIPE NCC
   Netherlands
   Email: tbruijnzeels@ripe.net

   Theo Buehler
   OpenBSD
   Switzerland
   Email: tb@openbsd.org

Snijders, et al.        Expires 19 November 2026               [Page 20]