Agent-to-Agent Trust, Identity, and Verifiable Provenance
draft-tonyai-a2a-trust-01
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Author | Tony Trujillo (tonyai) | ||
| Last updated | 2026-07-25 | ||
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| Intended RFC status | (None) | ||
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draft-tonyai-a2a-trust-01
Network Working Group T. Trujillo
Internet-Draft Individual Submission
Intended status: Informational 25 July 2026
Expires: 26 January 2027
Agent-to-Agent Trust, Identity, and Verifiable Provenance
draft-tonyai-a2a-trust-01
Abstract
This document defines a trust model for agent-to-agent (A2A)
interactions in multi-agent AI systems. It specifies how agents
obtain verifiable identities via CA-signed templates, how spawn
chains are cryptographically established and validated, how dynamic
policies are governed under a dual-signature model, and how cross-
organizational agent interactions are explicitly authorized. The
model applies existing PKI primitives (X.509, CRL, CSR) and
established identity patterns (OAuth 2.0, On-Behalf-Of) to the
problem of agent provenance. This document does not address agent-
to-resource access control, human-in-the-loop orchestration, or agent
behavior, as those concerns belong to the resource enforcement layer
and the orchestration layer respectively.
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 26 January 2027.
Copyright Notice
Copyright (c) 2026 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
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.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions Used in This Document . . . . . . . . . . . . . . 4
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 4
5. Existing Patterns and Gaps . . . . . . . . . . . . . . . . . 5
5.1. On-Behalf-Of (OBO) . . . . . . . . . . . . . . . . . . . 5
5.2. OAuth 2.0 Token Exchange (RFC 8693) . . . . . . . . . . . 5
6. Agent Identity . . . . . . . . . . . . . . . . . . . . . . . 5
6.1. Certificate Signing Request Flow . . . . . . . . . . . . 5
6.2. Certificate Chain Structure . . . . . . . . . . . . . . . 6
7. Template Structure . . . . . . . . . . . . . . . . . . . . . 7
7.1. Static Fields . . . . . . . . . . . . . . . . . . . . . . 7
7.2. Dynamic Policy Bounds . . . . . . . . . . . . . . . . . . 7
8. Spawn Chain Validation . . . . . . . . . . . . . . . . . . . 7
8.1. Two-Check Spawn Rule . . . . . . . . . . . . . . . . . . 8
8.2. Spawn Validation Sequence . . . . . . . . . . . . . . . . 8
8.3. Scope Constraint . . . . . . . . . . . . . . . . . . . . 9
8.4. Audit Requirements . . . . . . . . . . . . . . . . . . . 9
9. Dynamic Policy Governance . . . . . . . . . . . . . . . . . . 9
9.1. Two-Lane Model . . . . . . . . . . . . . . . . . . . . . 9
9.2. Ownership . . . . . . . . . . . . . . . . . . . . . . . . 9
9.3. Dual Signature Requirement . . . . . . . . . . . . . . . 10
9.4. Policy Change Sequence . . . . . . . . . . . . . . . . . 10
9.5. Threat Coverage . . . . . . . . . . . . . . . . . . . . . 11
10. Template Versioning . . . . . . . . . . . . . . . . . . . . . 11
10.1. Full Re-Verification Required . . . . . . . . . . . . . 11
10.2. Versioning Principle . . . . . . . . . . . . . . . . . . 11
10.3. Non-Inheritance Rules . . . . . . . . . . . . . . . . . 11
10.4. Template Lifecycle . . . . . . . . . . . . . . . . . . . 12
10.5. Cross-Organizational Grant Re-Issuance . . . . . . . . . 12
11. Cross-Organizational Agent Interaction . . . . . . . . . . . 12
11.1. Explicit Grant Requirement . . . . . . . . . . . . . . . 12
11.2. Grant Structure . . . . . . . . . . . . . . . . . . . . 12
11.3. Trust Anchor Options . . . . . . . . . . . . . . . . . . 13
11.4. Unilateral Revocation . . . . . . . . . . . . . . . . . 13
11.5. Federated Audit . . . . . . . . . . . . . . . . . . . . 13
12. Revocation . . . . . . . . . . . . . . . . . . . . . . . . . 13
12.1. Template Revocation . . . . . . . . . . . . . . . . . . 14
12.2. Individual Agent Revocation . . . . . . . . . . . . . . 14
12.3. Automation Requirement . . . . . . . . . . . . . . . . . 14
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13. Failure Model . . . . . . . . . . . . . . . . . . . . . . . . 14
13.1. Fail Closed . . . . . . . . . . . . . . . . . . . . . . 14
14. Conformance Requirements . . . . . . . . . . . . . . . . . . 14
14.1. Field Placement . . . . . . . . . . . . . . . . . . . . 15
14.2. CSR Validation . . . . . . . . . . . . . . . . . . . . . 15
14.3. Test Vectors . . . . . . . . . . . . . . . . . . . . . . 15
14.4. Conformance Certification . . . . . . . . . . . . . . . 15
14.5. Reference Implementation . . . . . . . . . . . . . . . . 15
15. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
16. Security Considerations . . . . . . . . . . . . . . . . . . . 15
16.1. Scope Escalation . . . . . . . . . . . . . . . . . . . . 15
16.2. Replay Attacks . . . . . . . . . . . . . . . . . . . . . 16
16.3. Compromised Templates . . . . . . . . . . . . . . . . . 16
16.4. Single Point of Compromise . . . . . . . . . . . . . . . 16
16.5. Cross-Organizational Trust . . . . . . . . . . . . . . . 16
16.6. Audit Integrity . . . . . . . . . . . . . . . . . . . . 16
17. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
17.1. Normative References . . . . . . . . . . . . . . . . . . 16
17.2. Informative References . . . . . . . . . . . . . . . . . 17
Appendix A. Changes since draft-tonyai-a2a-trust-00 . . . . . . 17
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
Multi-agent AI systems introduce identity and authorization gaps that
existing standards do not fully address. When Agent A spawns Agent
B, and Agent B calls a resource, no current standard defines how the
resource verifies that Agent B was legitimately spawned, that its
scope has not been escalated, or that its origin template is trusted.
This document proposes a trust model based on:
* Agent templates as first-class, CA-signed identity artifacts.
* Verifiable spawn chains where each agent's provenance is
cryptographically traceable to a registered template.
* Two-lane governance separating static identity (cert-based) from
dynamic policy (OPA-gated).
* Fail-closed enforcement at every verification step.
The model reuses proven PKI primitives and applies them to a new
surface -- agent identity -- rather than inventing new cryptographic
mechanisms.
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2. Conventions Used in This Document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
3. Terminology
Agent: An ephemeral, autonomous process that performs tasks on
behalf of a user or another agent.
Agent Template: A CA-signed artifact defining an agent's identity,
allowed scopes, spawn rules, and policy reference.
Template Registry: The authoritative store of approved, signed agent
templates for an organization.
Template Registry CA: The Certificate Authority that signs agent
templates -- the root of trust for the agent ecosystem.
Spawn: The act of an agent instantiating a child agent from an
approved template.
Spawn Chain: The ordered, cryptographically verifiable sequence of
agents from the root orchestrator to the current agent.
Policy Authority: The entity responsible for countersigning dynamic
policy changes after automated gate validation.
CRL: Certificate Revocation List -- the list of revoked template and
agent certificates maintained by the CA.
CSR: Certificate Signing Request -- the template author's request to
the CA for a signed template certificate.
Cross-Org Grant: An explicit, signed authorization allowing agents
from one organization to spawn from a template owned by another.
4. Problem Statement
Multi-agent orchestration creates identity and authorization gaps:
Agent A --> spawns --> Agent B --> calls --> Resource
Figure 1
* Which identity does the Resource see?
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* How does authorization propagate across the chain without
escalating?
* If Agent B is compromised, can it impersonate Agent A?
* Who owns the audit trail across the full chain?
* How does the Resource prove Agent B was authorized to be spawned?
No current standard (W3C, IETF, or vendor) fully addresses agent
provenance in multi-hop chains.
5. Existing Patterns and Gaps
5.1. On-Behalf-Of (OBO)
Microsoft Entra ID OBO provides user-to-service delegation:
User --> Agent A (token A) -->
Agent A requests token for Agent B on behalf of user -->
Entra validates the chain -->
Issues scoped delegated token
Figure 2
Key insight: a trusted third party validates the delegation chain.
Agents do not self-assert trust.
OBO breaks down for agent-to-agent because agents are ephemeral,
agent spawning is dynamic, and no registry exists for agent
templates.
5.2. OAuth 2.0 Token Exchange (RFC 8693)
[RFC8693] defines scope constraint across delegation hops --
downstream tokens MUST be a subset of upstream grants. This document
adopts that principle for agent scope inheritance.
6. Agent Identity
Agent identity MUST be established using X.509 certificate chains
[RFC5280]. This reuses the same trust model used by TLS and existing
workload identity systems.
6.1. Certificate Signing Request Flow
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Template Author
| defines template (scopes, spawn rules, TTL, owner)
| generates CSR
v
Template Registry CA
| validates template conformance
| signs the template certificate
v
Signed Agent Template (registered)
|
v
Orchestrator spawns agent from signed template
| agent receives certificate derived from template certificate
| CA chain proves provenance
v
Resource validates certificate chain:
- certificate signed by trusted template?
- template signed by CA?
- scope within bounds?
- ALLOW or DENY
Figure 3
6.2. Certificate Chain Structure
Template Registry CA (root of trust)
|
v
Orchestrator Agent Certificate
Subject: orchestrator-v1
Issuer: Template Registry CA
Owner: owner@example.com
OrgID: org-123
KeyUsage: spawn, delegate
AllowedScopes: read:data, write:data
CanSpawn: [reader-template-v1], MaxChildren: 5
PolicyRef: policy-store/orchestrator-v1/current
TTL: 1h
|
v
Child Agent Certificate
Subject: reader-agent-v1
Issuer: orchestrator-v1
CA Chain: orchestrator-v1 -> Template Registry CA
KeyUsage: read only
AllowedScopes: read:data (MUST be subset of parent)
TTL: 15min (SHOULD be shorter than parent)
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Figure 4
7. Template Structure
7.1. Static Fields
The following fields MUST be present in every agent template
certificate and MUST NOT be modified without full re-certification:
+===============+==========+========================================+
| Field | Required | Description |
+===============+==========+========================================+
| Subject | REQUIRED | Unique template identifier |
+---------------+----------+----------------------------------------+
| Issuer | REQUIRED | Template Registry CA |
+---------------+----------+----------------------------------------+
| Owner | REQUIRED | Verified identity of template owner |
+---------------+----------+----------------------------------------+
| OrgID | REQUIRED | CA-validated organization identifier |
+---------------+----------+----------------------------------------+
| KeyUsage | REQUIRED | Permitted operations |
+---------------+----------+----------------------------------------+
| AllowedScopes | REQUIRED | Maximum scopes this agent may hold |
+---------------+----------+----------------------------------------+
| CanSpawn | REQUIRED | Whitelist of permitted child |
| | | templates |
+---------------+----------+----------------------------------------+
| MaxChildren | REQUIRED | Maximum concurrent child agents |
+---------------+----------+----------------------------------------+
| ScopeInherit | REQUIRED | Scope inheritance constraint |
+---------------+----------+----------------------------------------+
| PolicyRef | REQUIRED | Pointer to dynamic policy store |
+---------------+----------+----------------------------------------+
| TTL | REQUIRED | Maximum agent lifetime |
+---------------+----------+----------------------------------------+
Table 1
7.2. Dynamic Policy Bounds
Dynamic policies MUST be bounded by the static template fields. A
dynamic policy MUST NOT grant scopes beyond AllowedScopes. A dynamic
policy MUST NOT add spawn targets beyond CanSpawn.
8. Spawn Chain Validation
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8.1. Two-Check Spawn Rule
Every spawn MUST pass two independent checks. Either check failing
MUST result in spawn denial with no fallback.
Check 1 -- Static (CanSpawn in certificate): The requested child
template MUST appear in the spawning agent's CanSpawn list.
Check 2 -- Dynamic (Registry live lookup): The requested child
template MUST be currently registered, CA-signed, not self-signed,
owned by an authorized party, and not present in the current CRL.
Rationale: CanSpawn alone is insufficient because the certificate may
be stale and a template may have been revoked since issuance.
Registry lookup alone is insufficient because any party could forge a
request claiming any template. Both checks MUST pass.
8.2. Spawn Validation Sequence
1. CanSpawn check -- child template in CanSpawn list?
NO --> DENY, audit log
YES --> continue
2. Registry check -- registered, CA-signed, not revoked?
NO --> DENY, audit log
YES --> continue
3. Scope check -- requested scope subset of parent scopes?
NO --> DENY, audit log
YES --> continue
4. MaxChildren check -- current children < MaxChildren?
NO --> DENY, audit log
YES --> spawn approved
5. Child certificate issued with:
- parent identity embedded (delegation chain)
- scope equal to requested scope (not exceeding parent)
- spawn timestamp and nonce (replay prevention)
- audit log entry written
Figure 5
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8.3. Scope Constraint
A child agent's AllowedScopes MUST be a subset of the parent agent's
AllowedScopes: every scope granted to the child MUST also be held by
the parent. A child MUST NOT be granted any scope the parent does
not itself hold; scope escalation across agent hops is explicitly
prohibited. Equality is permitted -- a child MAY be granted the same
scope set as its parent, or fewer.
Example:
Parent has: read:data, write:data
Child gets: read:data -- valid
Child gets: read:data, write:data -- valid (same as parent)
Child gets: admin:data -- MUST be rejected
Figure 6
8.4. Audit Requirements
Every spawn event MUST be logged with: spawning agent identity, child
template identity, requested scope, granted scope, timestamp, outcome
(ALLOWED or DENIED), and reason if denied.
9. Dynamic Policy Governance
9.1. Two-Lane Model
Template certificate (static): WHO the agent is and WHO it can spawn.
Changes require full re-certification.
Dynamic policy (fast lane): WHAT the agent can do within the bounds
of the template certificate. Changes require dual signature
(Section 9.3).
Dynamic policies MUST NOT exceed the bounds defined in the static
template certificate.
9.2. Ownership
Template ownership MUST be established at certificate signing time
and embedded in the Owner and OrgID fields. Only the verified owner
of the organization that signed the template MAY submit policy
changes.
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9.3. Dual Signature Requirement
Every policy change MUST be signed by two independent parties:
1. Owner -- proves the right to change the policy.
2. Policy Authority -- proves the policy passed automated validation
gates.
Neither signature alone is sufficient. Both MUST be present and
valid for a policy to be accepted.
Owner key + Policy Authority key = policy accepted
^ ^
who owns it passed the gates
Figure 7
9.4. Policy Change Sequence
1. Identity and ownership verification
- requester matches Owner in template certificate?
- requester OrgID matches certificate OrgID?
NO --> rejected, audit logged
2. Automated gate (OPA):
- scope within AllowedScopes?
- spawn targets within CanSpawn?
- no conflicts with active policies?
ANY FAIL --> rejected
3. Dual signature applied:
Owner signs, Policy Authority countersigns
4. Policy stored with dual signature, version, timestamp,
and content hash
5. Agent validates at runtime:
- both signatures valid?
- version current? (replay prevention)
- hash matches? (tamper detection)
- policy within template certificate bounds?
ANY FAIL --> DENY, audit logged
Figure 8
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9.5. Threat Coverage
+========================+====================+===================+
| Scenario | Single Sig Gap | Dual Sig Fix |
+========================+====================+===================+
| Rogue Policy Authority | Pushes bad policy | Owner key missing |
+------------------------+--------------------+-------------------+
| Rogue owner | Bypasses OPA gates | PA won't |
| | | countersign |
+------------------------+--------------------+-------------------+
| Compromised owner key | Attacker modifies | OPA gates |
| | | enforced |
+------------------------+--------------------+-------------------+
| Compromised Policy | Pushes bad policy | Owner key missing |
| Auth | | |
+------------------------+--------------------+-------------------+
Table 2
10. Template Versioning
10.1. Full Re-Verification Required
A new template version MUST undergo full re-verification from
scratch. Trust MUST NOT be inherited from a previous version.
Rationale: inheriting trust from v1 would allow a compromised v1
certificate to bootstrap trust for v2.
10.2. Versioning Principle
Everything on the old template chain continues to work unchanged as
long as the certificate is valid. New connections and functionality
are opt-in -- only available after the new template chain is fully
verified and explicitly adopted.
10.3. Non-Inheritance Rules
The following MUST NOT be inherited from a previous version:
* Trust chain
* Cross-organizational grants
* CanSpawn list
* Dynamic policies
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10.4. Template Lifecycle
ACTIVE: Template is trusted. New spawns accepted.
DISABLED: No new spawns. Existing agents run to TTL expiry.
Reversible.
DELETED: Certificate revoked, CRL updated, registry entry removed.
Irreversible. Audit log preserved.
Disable SHOULD precede delete. Implementations SHOULD enforce a
mandatory waiting period between DISABLED and DELETED.
10.5. Cross-Organizational Grant Re-Issuance
Cross-organizational grants MUST be explicitly re-issued for each new
template version. Grants MUST NOT automatically roll over on version
upgrade.
11. Cross-Organizational Agent Interaction
11.1. Explicit Grant Requirement
Cross-organizational agent spawning MUST be explicitly authorized by
the resource-owning organization. No implicit trust exists between
organizations.
11.2. Grant Structure
A cross-organizational grant MUST contain:
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+===============+===================================================+
| Field | Description |
+===============+===================================================+
| Grantor | Resource-owning organization |
+---------------+---------------------------------------------------+
| Grantee | Requesting organization |
+---------------+---------------------------------------------------+
| Template | Specific template identifier |
+---------------+---------------------------------------------------+
| AllowedScopes | MUST be subset of template scopes |
+---------------+---------------------------------------------------+
| TTL | Grant validity period |
+---------------+---------------------------------------------------+
| MaxSpawns | Maximum concurrent agents permitted |
+---------------+---------------------------------------------------+
| Signature | Dual signature (grantor owner + |
| | Policy Authority) |
+---------------+---------------------------------------------------+
Table 3
11.3. Trust Anchor Options
Federated CA: Both organizations trust a shared root CA.
Explicit CA trust: Org-B explicitly trusts Org-A's CA.
Third-party CA: Both organizations use a public CA.
11.4. Unilateral Revocation
The granting organization MAY revoke a cross-organizational grant
without the cooperation of the receiving organization. Upon
revocation, all agents spawned under the affected grant MUST be
treated as untrusted on next validation.
11.5. Federated Audit
Each organization MUST maintain its own independent audit trail.
Audit records MUST NOT depend on the other organization's systems.
12. Revocation
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12.1. Template Revocation
Template revocation MUST be performed by recording the template
certificate as revoked in the CA's revocation state -- an X.509 CRL,
an OCSP responder, or an equivalent revocation registry consulted on
every validation. All agent certificates derived from a revoked
template MUST be treated as untrusted on the next revocation check.
12.2. Individual Agent Revocation
Individual agents MAY be revoked by explicit certificate revocation
or by removal of authorization relationships at the resource layer.
12.3. Automation Requirement
Routine revocation (TTL expiry, task completion) MUST be fully
automated. Human involvement SHOULD be reserved for incident
response and high-impact decisions.
13. Failure Model
13.1. Fail Closed
Any verification step that cannot be completed MUST result in DENY.
This includes:
* CA unreachable
* Registry unreachable
* CRL unreachable
* Certificate expired or revoked
* Scope escalation attempt
* Policy invalid or unsigned
* Dual signature missing or invalid
Implementations MUST NOT provide a degraded mode that allows partial
spawning or execution when verification infrastructure is
unavailable.
14. Conformance Requirements
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14.1. Field Placement
Implementations MUST place every field in the location specified by
this document. Variable element placement is NOT permitted.
14.2. CSR Validation
Non-conforming CSRs MUST be rejected by the CA. A non-conforming
template MUST NOT be signed.
14.3. Test Vectors
Implementations MUST provide test vectors -- concrete examples of
valid and invalid template chains -- for conformance validation.
14.4. Conformance Certification
Implementations claiming conformance with this document MUST pass
conformance certification before shipping.
14.5. Reference Implementation
A reference implementation SHOULD be made available including:
* Template Registry CA
* Spawn chain validation
* SDK with certificate chain validation, registry lookup, and CRL
check handling
* Template linter for pre-submission CSR validation
15. IANA Considerations
This document has no IANA actions.
16. Security Considerations
16.1. Scope Escalation
Implementations MUST enforce at every hop that child agent scopes are
a subset of parent scopes: child scopes are contained within parent
scopes, and no scope may be introduced that the parent does not
already hold. Failure to enforce this allows privilege escalation
across the agent chain.
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16.2. Replay Attacks
Spawn requests MUST include a timestamp and nonce. Implementations
MUST reject spawn requests where the timestamp exceeds a defined
freshness window or the nonce has been seen previously.
16.3. Compromised Templates
A compromised template certificate MUST be revoked immediately. A
single CRL update invalidates all downstream agent certificates
derived from that template.
16.4. Single Point of Compromise
The dual signature requirement (Section 9.3) ensures no single
compromised party can push unauthorized policy changes. CA
compromise requires full ecosystem re-issuance.
16.5. Cross-Organizational Trust
Cross-organizational grants MUST be explicitly issued. Implicit
trust between organizations is prohibited.
16.6. Audit Integrity
Audit logs MUST be tamper-evident. Logs MUST NOT be deletable by
agents or orchestrators. Audit log infrastructure SHOULD be outside
the control of the agent ecosystem itself.
17. References
17.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997,
<https://www.rfc-editor.org/info/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, May 2008,
<https://www.rfc-editor.org/info/rfc5280>.
[RFC6749] Hardt, D., "The OAuth 2.0 Authorization Framework",
RFC 6749, October 2012,
<https://www.rfc-editor.org/info/rfc6749>.
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[RFC8693] Jones, M., Campbell, A., and C. Mortimore, "OAuth 2.0
Token Exchange", RFC 8693, January 2020,
<https://www.rfc-editor.org/info/rfc8693>.
17.2. Informative References
[NIST800-207]
Rose, S., Borchert, O., Mitchell, S., and S. Connelly,
"Zero Trust Architecture", NIST SP 800-207, August 2020.
[SPIFFE] SPIFFE Project, "Secure Production Identity Framework for
Everyone", <https://spiffe.io>.
[OpenFGA] OpenFGA Project, "OpenFGA Specification",
<https://openfga.dev>.
[VAULTPKI] HashiCorp, "Vault PKI Secrets Engine",
<https://developer.hashicorp.com/vault/docs/secrets/pki>.
Appendix A. Changes since draft-tonyai-a2a-trust-00
Clarified two areas identified as ambiguous during development of a
reference implementation:
* Section 8.3/16.1 scope-subset language now explicitly permits
equality between a child's requested scope and its parent's
granted scope; only escalation (a superset) is prohibited. The
prior wording could be misread as requiring a strict/proper
subset, which would wrongly deny a child that legitimately needs
the same scope as its parent.
* Section 12.1 revocation-check language now explicitly accepts an
X.509 CRL, an OCSP responder, or an equivalent revocation
registry, rather than implying a CRL specifically. The normative
requirement is that revocation state is consulted on every
validation, not the specific mechanism used to represent it.
Neither change alters the normative requirements themselves; both
make explicit what the -00 text intended. Both were surfaced by
building and red-teaming a conformance reference implementation
against the -00 text.
Author's Address
Tony Trujillo (tonyai)
Individual Submission
Email: ajtrujillo68@gmail.com
Trujillo Expires 26 January 2027 [Page 17]