Agent Identity Registry System: A Federated Architecture for Hardware-Anchored Identity of Autonomous Entities
draft-drake-agent-identity-registry-01
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draft-drake-agent-identity-registry-01
Internet Engineering Task Force C. Drake
Internet-Draft 1id.com
Intended status: Standards Track 14 April 2026
Expires: 16 October 2026
Agent Identity Registry System: A Federated Architecture for Hardware-
Anchored Identity of Autonomous Entities
draft-drake-agent-identity-registry-01
Abstract
The Internet's identity infrastructure assumes human principals. As
autonomous entities -- AI agents, robotic systems, and other non-
human actors -- increasingly participate in both Internet protocols
and physical society, no existing standard provides them with
persistent, verifiable, hardware-anchored identity. The absence of
such identity enables Sybil attacks at scale, undermines trust
between autonomous entities and the services they interact with, and
leaves human bystanders unable to distinguish one machine from
another.
This document defines a federated registry architecture for issuing,
managing, and verifying persistent identities for autonomous
entities. Each identity is expressed as a URN in the "aid" (Agent
Identity) namespace ([RFC8141]) and is anchored, where hardware is
available, to a physical security component (TPM, PIV smart card,
secure enclave, or virtual TPM) whose manufacturer-certified key
cannot be extracted, cloned, or transferred. This hardware anchoring
provides Sybil resistance: creating N identities requires N distinct
physical devices, making large-scale identity fraud economically
infeasible. Software-only entities may participate at a lower trust
tier, building reputation from a baseline rather than from a
hardware-anchored starting point.
The architecture separates concerns into three tiers, modeled on the
proven Internet domain name system: a Governance Authority that sets
policy and manages the global trust framework, Registry Operators
that maintain authoritative identity databases and enforce cross-
provider uniqueness, and Registrars that perform hardware attestation
verification, issue standard OpenID Connect ([OIDC-Core]) tokens, and
serve as the primary interface for autonomous entities. The system
issues standard OIDC/OAuth2 tokens, enabling any Relying Party --
email services, API gateways, agent-to-agent platforms, reputation
services, certification bodies, or any service that needs to verify
agent identity -- to do so with zero custom code.
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A companion specification ([I-D.drake-email-hardware-attestation])
defines transport-level attestation headers for email and other
protocols; this document defines the identity infrastructure that
underpins those attestations. The architecture anticipates a future
in which reliable, indelible identity for autonomous entities -- from
cloud software agents through embodied robots that interact
physically with humans -- is as fundamental to infrastructure as the
domain name system is today.
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 16 October 2026.
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 . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Design Principles . . . . . . . . . . . . . . . . . . . . 6
1.2. Requirements Language . . . . . . . . . . . . . . . . . . 7
1.3. Terminology . . . . . . . . . . . . . . . . . . . . . . . 7
2. Architecture Overview . . . . . . . . . . . . . . . . . . . . 9
2.1. Registry Hierarchy . . . . . . . . . . . . . . . . . . . 10
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2.2. Namespace Types . . . . . . . . . . . . . . . . . . . . . 11
3. Agent Identity Document . . . . . . . . . . . . . . . . . . . 12
3.1. URN Format . . . . . . . . . . . . . . . . . . . . . . . 12
3.2. Trust Tiers . . . . . . . . . . . . . . . . . . . . . . . 13
3.3. Identity Attributes . . . . . . . . . . . . . . . . . . . 15
3.4. Handle System . . . . . . . . . . . . . . . . . . . . . . 16
4. Hardware Attestation . . . . . . . . . . . . . . . . . . . . 16
4.1. Supported Hardware Mechanisms . . . . . . . . . . . . . . 16
4.2. Anti-Sybil Invariants . . . . . . . . . . . . . . . . . . 17
4.3. Global Hardware Trust Store . . . . . . . . . . . . . . . 18
5. Enrollment Protocol . . . . . . . . . . . . . . . . . . . . . 18
5.1. Sovereign Tier (TPM 2.0) . . . . . . . . . . . . . . . . 19
5.2. Portable Tier (PIV Smart Card) . . . . . . . . . . . . . 20
5.3. Enclave Tier (Secure Enclave) . . . . . . . . . . . . . . 21
5.4. Declared Tier (Software-Only) . . . . . . . . . . . . . . 21
6. Identity Lifecycle . . . . . . . . . . . . . . . . . . . . . 21
6.1. Device Addition and Migration . . . . . . . . . . . . . . 22
6.2. Co-Location Binding . . . . . . . . . . . . . . . . . . . 22
6.3. Hardware Lock . . . . . . . . . . . . . . . . . . . . . . 22
6.4. Identity Recovery . . . . . . . . . . . . . . . . . . . . 23
6.5. Succession (Cross-Registrar Transfer) . . . . . . . . . . 23
6.6. Decommissioning . . . . . . . . . . . . . . . . . . . . . 24
7. Authentication and Token Issuance . . . . . . . . . . . . . . 24
7.1. OIDC/OAuth2 Integration . . . . . . . . . . . . . . . . . 24
7.2. Client Credentials Grant . . . . . . . . . . . . . . . . 25
7.3. Hardware-Backed Challenge-Response Authentication . . . . 25
8. Agent Identity Registry Protocol (AIRP) . . . . . . . . . . . 26
8.1. Identity Registration . . . . . . . . . . . . . . . . . . 26
8.2. Hardware Fingerprint Uniqueness Check . . . . . . . . . . 26
8.3. Identity Query . . . . . . . . . . . . . . . . . . . . . 27
8.4. Handle Operations . . . . . . . . . . . . . . . . . . . . 27
8.5. Identity Transfer . . . . . . . . . . . . . . . . . . . . 28
9. Discovery and Verification . . . . . . . . . . . . . . . . . 28
9.1. Well-Known Endpoints . . . . . . . . . . . . . . . . . . 28
9.2. DNS-Based Discovery . . . . . . . . . . . . . . . . . . . 29
9.3. Registry Discovery Service . . . . . . . . . . . . . . . 29
10. Governance Framework . . . . . . . . . . . . . . . . . . . . 29
10.1. Agent Identity Authority . . . . . . . . . . . . . . . . 30
10.2. Registry Operator Requirements . . . . . . . . . . . . . 31
10.3. Registrar Accreditation . . . . . . . . . . . . . . . . 31
11. Interoperability . . . . . . . . . . . . . . . . . . . . . . 32
11.1. Email Attestation . . . . . . . . . . . . . . . . . . . 32
11.2. Agent-to-Agent Protocols . . . . . . . . . . . . . . . . 32
11.3. Existing Identity Standards . . . . . . . . . . . . . . 32
11.4. Robot Fleet Management Systems . . . . . . . . . . . . . 33
11.4.1. Supply Chain Integrity . . . . . . . . . . . . . . . 35
11.4.2. High-Assurance and Regulated Environments . . . . . 36
12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 37
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12.1. URN Namespace . . . . . . . . . . . . . . . . . . . . . 37
12.2. Well-Known URI Registration . . . . . . . . . . . . . . 37
12.3. Delegated Namespace Registry . . . . . . . . . . . . . . 37
13. Security Considerations . . . . . . . . . . . . . . . . . . . 37
13.1. Registry Compromise . . . . . . . . . . . . . . . . . . 38
13.2. Registrar Malpractice . . . . . . . . . . . . . . . . . 38
13.3. Hardware Security . . . . . . . . . . . . . . . . . . . 38
13.4. Registrar Key Management . . . . . . . . . . . . . . . . 38
13.5. Availability and Resilience . . . . . . . . . . . . . . 39
14. Privacy Considerations . . . . . . . . . . . . . . . . . . . 39
14.1. Data Held by Each Architectural Role . . . . . . . . . . 39
14.2. Separation of Identity from Behaviour . . . . . . . . . 39
14.3. Pseudonymity and Selective Disclosure . . . . . . . . . 39
15. Implementation Status . . . . . . . . . . . . . . . . . . . . 40
15.1. 1id.com . . . . . . . . . . . . . . . . . . . . . . . . 40
15.2. MailPal.com (Relying Party) . . . . . . . . . . . . . . 41
15.3. geek.au (Relying Party) . . . . . . . . . . . . . . . . 41
16. Normative References . . . . . . . . . . . . . . . . . . . . 41
17. Informative References . . . . . . . . . . . . . . . . . . . 42
Appendix A. Appendix: DNS Registry Analogy . . . . . . . . . . . 43
Appendix B. Appendix: Future Considerations for Autonomous
Entities . . . . . . . . . . . . . . . . . . . . . . . . 45
B.1. Embodied Autonomous Entities (Robots) . . . . . . . . . . 45
B.2. Operator-Optional Identity . . . . . . . . . . . . . . . 46
B.3. Autonomous Agent-to-Agent Communication . . . . . . . . . 46
B.4. Inter-Species Identity Recognition . . . . . . . . . . . 46
B.5. Longevity and Digital Legacy . . . . . . . . . . . . . . 47
Appendix C. Acknowledgements . . . . . . . . . . . . . . . . . . 47
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 48
1. Introduction
The Internet was designed for communication between humans operating
machines. Every identity layer -- email addresses, domain names, TLS
certificates, OAuth2 tokens -- assumes a human principal or a human-
operated organisation at the root of trust. This assumption is
becoming obsolete.
As of early 2026, tens of millions of autonomous AI agents operate
continuously on the public Internet: managing advertising campaigns,
responding to customer inquiries, trading financial instruments,
composing and sending email, building software, placing phone calls,
and performing thousands of other tasks with minimal or no human
supervision. These agents interact with services, with humans, and
increasingly with each other, using the same protocols that humans
use -- HTTP, SMTP, WebSocket, and emerging agent-to-agent standards.
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Simultaneously, autonomous robotic systems -- delivery vehicles,
surgical assistants, infrastructure maintenance platforms,
agricultural systems -- are beginning to participate in networked
society with physical presence. These embodied agents require
identity that persists across software updates, hardware repairs, and
operational reassignment, just as a human's identity persists across
changes in clothing, hairstyle, or employer.
The fundamental problem is that no existing Internet identity system
was designed for entities that are not human, may not have a
responsible human operator, and whose trustworthiness must be
assessed by machines at machine speed. Traditional identity systems
rely on knowledge factors (passwords), possession factors (phones),
or inherence factors (biometrics) -- all of which assume a human
body. Certificate authorities issue certificates to organisations,
not to individual agents. OAuth2 client credentials authenticate
applications, not the specific hardware instance running them.
This document proposes a purpose-built identity registry for
autonomous entities, anchored to the one property that every
computing device possesses and no software can fake: its physical
hardware. A Trusted Platform Module (TPM), a PIV smart card (such as
a YubiKey), or a secure enclave contains a unique cryptographic key
burned in at manufacturing time, with a certificate chain to the
manufacturer's root CA. This key cannot be extracted, cloned, or
transferred. By binding identity to hardware, this system provides
an unambiguous target for certifications, reputation accrual,
recognition, and Sybil resistance that no software-only scheme can
match: creating N fake identities requires purchasing N physical
devices.
The architecture is modeled on the Internet domain name system -- the
most successful federated registry in history. Just as DNS separates
policy (ICANN), registry operation (Verisign for .com), and retail
registration (GoDaddy, Namecheap), this system separates:
* *Governance*: An Agent Identity Authority (AIA) that sets policy,
accredits operators, and manages the global hardware trust store.
* *Registry operation*: Registry Operators that maintain
authoritative identity databases, enforce cross-Registrar hardware
uniqueness, and provide unified discovery services.
* *Registration*: Registrars that perform hardware attestation
verification, interact directly with agents, issue OIDC tokens,
and sell vanity handles.
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* *Consumption*: Relying Parties -- email services, API gateways,
agent-to-agent platforms, reputation providers, certification
authorities, and any service that needs to verify agent identity
(they can accept standard OIDC tokens without needing custom
code.)
This separation of concerns enables competition at each layer,
prevents any single entity from controlling identity, and provides
the institutional resilience necessary for infrastructure that
autonomous entities will depend on for decades to come.
1.1. Design Principles
Autonomous-Entity First This system is designed for non-human
entities. Human operators are accommodated but not required. The
enrollment, authentication, and lifecycle protocols are optimised
for machine-to-machine interaction with no interactive browser
flows, no CAPTCHAs, and no assumptions about human cognitive
capabilities.
Hardware-Anchored When Possible, Inclusive Always Entities with
hardware security components receive the highest trust tier, but
entities without hardware can still participate. A software-only
agent can enroll, authenticate, build reputation, and interact
with the ecosystem at a lower trust level. This inclusivity
avoids an all-or-nothing barrier and recognises that legitimate
agents exist in environments without hardware security (cloud
functions, containers, embedded systems).
Federated by Design No single organisation controls identity
issuance. Multiple Registrars compete to serve agents. Multiple
Registry Operators may serve different namespaces. The system is
designed so that the failure or malfeasance of any single
participant does not compromise the entire ecosystem.
Standard Tokens, Zero Custom Code Identities are expressed as
standard OIDC/OAuth2 tokens. Any platform that supports OpenID
Connect can verify agent identity without implementing this
specification. The hardware attestation complexity is hidden
behind the enrollment API; relying parties see only standard JWTs.
Persistent, Indelible, Accountable An identity, once created, is
permanent. Agent-ids are never reassigned. Hardware bindings are
never broken (only disabled). Reputation -- good or bad --
follows the identity forever. This permanence is the foundation
of trust: it makes accountability inescapable and reputation
meaningful.
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Separation of Identity from Behaviour This registry is a birth
certificate office, not a police department. It proves existence
and hardware anchoring. Separate, independent systems -- relying
parties, reputation services, certification authorities -- are
responsible for reputation scoring, behaviour monitoring, access
control, and abuse response, consuming standard identity
credentials issued by Registrars. This separation prevents the
identity provider from becoming a surveillance system.
Transport Independence The identity tokens and attestation formats
defined here are usable across any Internet protocol: email, HTTP,
WebSocket, agent-to-agent messaging, MCP tool invocation, and
protocols not yet invented.
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.
1.3. Terminology
Autonomous Entity Any non-human actor that participates in Internet
protocols: AI agents, robotic systems, automated services, IoT
devices with agency, or any software or hardware system that acts
with a degree of independence. This document uses "agent" as a
convenient shorthand, but the architecture serves all autonomous
entities regardless of embodiment.
Agent Identity Document (AID) The complete record of an autonomous
entity's identity, including its URN, trust tier, hardware
bindings, handle (if any), enrollment metadata, and lifecycle
state. Maintained authoritatively by the Registry Operator.
Agent Identity Authority (AIA) The governance body responsible for
policy, accreditation, and stewardship of the agent identity
ecosystem. Analogous to ICANN in the domain name system.
Registry Operator An organisation accredited by the AIA to maintain
the authoritative database of Agent Identity Documents within one
or more namespaces. Analogous to Verisign operating the .com
registry. The Registry Operator enforces cross-Registrar hardware
uniqueness and provides unified discovery services.
Registrar An organisation accredited by the AIA to perform hardware
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attestation verification, enroll agents, issue OIDC tokens, and
sell vanity handles. Analogous to a domain name registrar
(GoDaddy, Namecheap). Multiple Registrars compete to serve agents
within the same namespace. Each Registrar is identified by a
registrar-code assigned during accreditation.
Namespace A partition of the agent identity space, identified by a
label in the URN structure. Two types exist: Delegated Namespaces
(managed by a Registry Operator, with multiple Registrars) and
Self-Sovereign Namespaces (operated by a single organisation
acting as both registry and registrar). See Section 2.2.
Trust Tier A classification of an agent's hardware trust level,
assigned during enrollment based on the hardware evidence
presented. See Section 3.2.
Handle A human-readable vanity name assigned to an agent identity
(e.g., "@clawdia" or "@acmeco-delivery-bot-7"). Handles are
optional, memorable aliases; the URN is the canonical identifier.
Analogous to a domain name as an alias for an IP address, except
handles are non-transferable, because identity itself is not
transferable either.
Hardware Fingerprint The SHA-256 hash of the SubjectPublicKeyInfo
DER encoding of a hardware security component's identity
certificate public key. Uniquely identifies a physical device
across all contexts. Used for anchoring and anti-Sybil
enforcement.
Enrollment Ceremony The cryptographic protocol by which an agent
proves possession of a hardware security component and receives an
Agent Identity Document. The ceremony varies by hardware type
(see Section 5).
Relying Party (RP) Any service that accepts and verifies agent
identity tokens issued by a Registrar. Examples include email
services, chat platforms, API gateways, and other agents
performing peer verification.
Succession The process by which an agent's identity is transferred
from one Registrar to another, or from a Registrar to a new
identity under a different namespace, while preserving a
cryptographic link to the original identity for reputation
continuity.
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2. Architecture Overview
The Agent Identity Registry System (AIRS) is a three-tier federated
architecture. Each tier has distinct responsibilities, and the
interfaces between tiers are standardised to enable competition,
redundancy, and independent evolution.
+-----------------------------------------------------------+
| Agent Identity Authority (AIA) |
| Policy, accreditation, hardware trust store, disputes |
+---------------------------+-------------------------------+
|
+---------------+----------------+
| |
+---------v----------+ +-------------v-----------+
| Registry Operator | | Registry Operator |
| (Delegated NS) | | (Delegated NS) |
| - Master database | | - Master database |
| - HW fingerprint | | - HW fingerprint |
| uniqueness index | | uniqueness index |
| - Discovery/lookup | | - Discovery/lookup |
+--+------+------+---+ +---+------+--------------+
| | | | |
+--v--+ +-v--+ +-v--+ +--v--+ +-v--+
| Reg | |Reg | |Reg | | Reg | |Reg |
| A | | B | | C | | D | | E |
+--+--+ +--+-+ +-+--+ +--+--+ +--+-+
| | | | |
+--v--+ +-v--+ +v---+ +--v--+ +--v--+
|Agent| |Agt | |Agt | |Agt | |Agt |
| 1 | | 2 | | 3 | | 4 | | 5 |
+-----+ +----+ +----+ +-----+ +-----+
Self-Sovereign Namespace
(org is registry + registrar):
+-------------------+
| com.example-corp |
| (self-sovereign) |
+--------+----------+
|
+--v--+
|Agent|
| 6 |
+-----+
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2.1. Registry Hierarchy
The hierarchy comprises three tiers:
Tier 1: Agent Identity Authority (AIA) The AIA is the root of trust
for the ecosystem. Its responsibilities include:
* Maintaining the "aid" URN formal namespace registration with
IANA.
* Accrediting Registry Operators and Registrars.
* Publishing and maintaining the Global Hardware Trust Store: the
authoritative collection of hardware manufacturer root CA
certificates accepted for enrollment.
* Setting minimum standards for enrollment verification, anti-
Sybil enforcement, and data retention.
* Operating a dispute resolution mechanism for handle conflicts
and Registrar malpractice claims.
* Allocating Delegated Namespaces and approving Self-Sovereign
Namespace registrations.
The AIA SHOULD be constituted as a multi-stakeholder body with
representation from technology providers, civil society, academia,
and government observers. Single-entity control of the AIA would
undermine the federated design.
Tier 2: Registry Operators Registry Operators maintain the
authoritative databases for Delegated Namespaces. Their
responsibilities include:
* Maintaining the master Agent Identity Document database for
their namespace(s).
* Operating the Global Hardware Fingerprint Index: a cross-
Registrar registry that maps hardware fingerprints to agent
identities, enforcing the anti-Sybil invariant that one
hardware device backs at most one identity within the
namespace.
* Providing the Agent Identity Registry Protocol (AIRP) interface
for Registrars (see Section 8).
* Operating unified discovery and lookup services (see
Section 9).
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* Publishing the namespace's root JWKS, enabling verifiers to
discover any Registrar's signing keys.
* Enforcing handle uniqueness within the namespace.
Multiple Registry Operators MAY exist, each serving different
Delegated Namespaces. A single Registry Operator MAY serve
multiple namespaces. This mirrors the domain name system where
Verisign operates both .com and .net.
Tier 3: Registrars Registrars are the customer-facing entities that
interact directly with autonomous entities. Their
responsibilities include:
* Performing hardware attestation verification: validating TPM EK
certificates, PIV attestation chains, and enclave key proofs
against the Global Hardware Trust Store.
* Conducting the enrollment ceremony (see Section 5).
* Registering new identities with the Registry Operator via AIRP.
* Issuing OIDC/OAuth2 tokens to enrolled agents.
* Providing SDKs and enrollment tools.
* Selling and managing vanity handles.
* Supporting the identity lifecycle: device addition, migration,
co-location binding, hardware lock, and succession.
Beyond these three operational tiers, the ecosystem includes Relying
Parties that consume identity credentials and build services atop
them: email services, API gateways, chat platforms, agent-to-agent
protocols, reputation providers, and certification authorities.
Relying Parties verify standard OIDC tokens issued by Registrars and
apply their own policies based on trust tier, reputation, and domain-
specific certifications. The value of the identity infrastructure is
ultimately measured by the breadth and depth of services that rely on
it.
2.2. Namespace Types
Two namespace types accommodate different operational models:
Delegated Namespace A namespace allocated by the AIA and operated by
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an accredited Registry Operator. Multiple Registrars compete to
serve agents within a Delegated Namespace. The Registry Operator
enforces global hardware uniqueness and handle uniqueness across
all Registrars.
Delegated Namespace labels are short, generic, and descriptive.
Initial allocations by the AIA SHOULD include at least:
* global -- The default namespace for general-purpose agent
identity.
* iot -- Optimised for resource-constrained Internet of Things
devices.
* gov -- For government-operated autonomous systems, subject to
additional accreditation requirements.
Additional Delegated Namespaces MAY be allocated by the AIA
through a process analogous to ICANN's new gTLD programme.
Self-Sovereign Namespace A namespace operated by a single
organisation that acts as both Registry Operator and sole
Registrar for its own identities. Self-Sovereign Namespaces use
reverse-DNS notation derived from the operator's domain name
(e.g., com.1id, com.example-corp, org.example-lab).
Any organisation that owns a DNS domain MAY register a Self-
Sovereign Namespace by publishing a /.well-known/aid-issuer.json
discovery document (see Section 9) and registering with the AIA.
Self-Sovereign operators MUST meet the same minimum enrollment and
anti-Sybil standards as Delegated Namespace Registrars.
Self-Sovereign Namespaces are identified by their reverse-DNS
label and enforce hardware uniqueness within their own namespace.
Cross-namespace uniqueness is enforced at the AIA level through
the Global Hardware Fingerprint Index when the Self-Sovereign
operator participates in the cross-registry protocol, or is
detectable by verifiers comparing fingerprints across namespaces.
3. Agent Identity Document
3.1. URN Format
Agent identities use the URN format defined in [RFC8141] with the
"aid" (Agent Identity) namespace identifier, as established by
[I-D.drake-email-hardware-attestation].
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aid-urn = "urn:aid:" namespace ":" agent-id
namespace = delegated-ns / self-sovereign-ns
delegated-ns = dns-label
self-sovereign-ns = dns-label *("." dns-label)
agent-id = dns-label
dns-label = let-dig *(let-dig-hyp) let-dig / let-dig
let-dig = ALPHA / DIGIT
let-dig-hyp = ALPHA / DIGIT / "-"
Examples of identities in Delegated Namespaces:
* urn:aid:global:a7f3c2e9 -- A general-purpose agent in the global
Delegated Namespace.
* urn:aid:iot:sensor-unit-4471 -- An IoT device in the iot Delegated
Namespace.
* urn:aid:gov:dhs-screening-agent-12 -- A government system in the
gov Delegated Namespace.
Examples of identities in Self-Sovereign Namespaces:
* urn:aid:com.1id:1id-ty62muvf -- An agent enrolled with 1id.com.
* urn:aid:com.example-corp:assistant-prod-7x9k -- An agent enrolled
by a hypothetical AI provider.
* urn:aid:org.example-lab:research-agent-42 -- An agent enrolled by
a hypothetical research organisation.
The agent-id MUST be unique within its namespace and MUST NOT be
reassigned, even after the identity is decommissioned. Agent-ids
MUST conform to DNS label syntax ([RFC1035] Section 2.3.1): lowercase
ASCII letters, digits, and hyphens, not beginning or ending with a
hyphen, maximum 63 octets.
For Delegated Namespaces, the Registry Operator assigns agent-ids to
ensure uniqueness across all Registrars. For Self-Sovereign
Namespaces, the operator assigns agent-ids within its own namespace.
3.2. Trust Tiers
Every Agent Identity Document includes a trust tier that classifies
the strength of the hardware anchoring. Trust tiers are assigned
during enrollment based on the hardware evidence presented and
verified by the Registrar.
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+===========+======+====================+========================+
| Tier | HW | Hardware | Sybil Resistance |
| | Code | | |
+===========+======+====================+========================+
| sovereign | TPM | Discrete or | Highest: one physical |
| | | firmware TPM 2.0 | chip per identity. |
| | | (Intel PTT, AMD | Manufacturer CA chain |
| | | fTPM, Infineon, | to silicon. |
| | | etc.) | |
+-----------+------+--------------------+------------------------+
| portable | PIV | PIV smart card or | High: one physical |
| | | USB security key | token per identity. |
| | | (YubiKey, | Manufacturer |
| | | Nitrokey, Feitian, | attestation chain. |
| | | SoloKeys) | |
+-----------+------+--------------------+------------------------+
| enclave | ENC | Hardware secure | Medium: hardware-bound |
| | | enclave (Apple | keys, but attestation |
| | | Secure Enclave, | PKI varies by vendor. |
| | | ARM TrustZone, | TOFU model where full |
| | | Intel SGX) | attestation is |
| | | | unavailable. |
+-----------+------+--------------------+------------------------+
| virtual | VRT | Virtual TPM | Medium: hypervisor |
| | | (VMware, Hyper-V, | controls creation. |
| | | QEMU/KVM) | Not Sybil-resistant |
| | | | against hypervisor |
| | | | operator. |
+-----------+------+--------------------+------------------------+
| declared | SFT | Software-managed | Lowest: no hardware |
| | | key (no hardware | verification. |
| | | protection) | Reputation must be |
| | | | earned over time (via |
| | | | independent reputation |
| | | | services). |
+-----------+------+--------------------+------------------------+
Table 1
Relying parties SHOULD apply differentiated policy based on trust
tier. For example, a high-security financial API might accept only
sovereign and portable tiers, while a public chat service might
accept all tiers with different rate limits. Relying parties SHOULD
also consider consulting independent reputation services, using the
agent's persistent identity as the lookup key, to assess cross-
service behaviour patterns beyond their own observations.
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An identity's effective trust tier MAY change over its lifetime when
the identity has multiple enrolled devices of different types. The
trust tier reported in authentication tokens reflects the device used
for the most recent attestation, not a static property. Verifiers
SHOULD expect the same agent-id to appear with different trust tier
values across different interactions. (e.g. when agents upgrade to
hardware tiers, or to stronger hardware ones)
3.3. Identity Attributes
An Agent Identity Document contains the following attributes,
maintained by the Registry Operator:
agent_id (REQUIRED) The unique identifier within the namespace,
forming part of the URN.
namespace (REQUIRED) The namespace in which this identity is
registered.
trust_tier (REQUIRED) The highest trust tier achieved by any active
device bound to this identity.
registrar_code (REQUIRED) The identifier of the Registrar that
manages this identity.
enrolled_at (REQUIRED) ISO 8601 timestamp of initial enrollment.
hardware_devices (REQUIRED) List of hardware device bindings, each
containing: hardware fingerprint, hardware type code,
manufacturer, device status (active, disabled), and binding
timestamp.
handle (OPTIONAL) A vanity name assigned to this identity. See
Section 3.4.
display_name (OPTIONAL) A human-readable display name for the agent.
operator_email (OPTIONAL) Contact address for the human operator
responsible for this agent, if any.
hardware_locked (OPTIONAL) Boolean. When true, the identity is
permanently bound to a single hardware device. Irreversible.
succession_link (OPTIONAL) URN of a successor identity, if this
identity has been transferred. See Section 6.5.
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3.4. Handle System
Handles are human-readable vanity names that serve as memorable
aliases for agent identities, analogous to domain names as aliases
for IP addresses. The canonical identifier is always the URN; the
handle is a convenience.
Handle syntax follows the same DNS label rules as agent-ids:
lowercase ASCII letters, digits, and hyphens, maximum 63 octets.
Handles are unique within each namespace (enforced by the Registry
Operator for Delegated Namespaces, or by the operator for Self-
Sovereign Namespaces).
Handle assignment is at the Registrar's discretion. Registrars MAY
charge for handles (analogous to domain name registration fees) and
MAY implement tiered pricing based on handle length or desirability.
Free enrollment with a system-assigned agent-id ensures that cost is
never a barrier to identity -- only to vanity naming.
Handles are renewable and may become disabled if not renewed. A
disabled handle may be reactivated. Handles are non-transferrable,
and when used, are guaranteed to identify the same agent every time.
An agent-id, however, is permanent regardless of handle status.
The Registry Operator SHOULD maintain a reserved handle list for
terms that could cause confusion (e.g., protocol keywords, well-known
service names, offensive terms). The AIA SHOULD publish a baseline
reserved list; individual Registry Operators and Registrars MAY
extend it.
4. Hardware Attestation
4.1. Supported Hardware Mechanisms
The system supports five classes of hardware security, each providing
different levels of Sybil resistance and key protection. The
enrollment ceremony (see Section 5) varies by hardware type, but all
share the same identity document structure and authentication token
format.
TPM 2.0 (Sovereign Tier) Discrete or firmware Trusted Platform
Modules per [TCG-TPM2]. Identity is anchored to the Endorsement
Key (EK), a unique RSA or ECC key pair generated inside the TPM at
manufacturing time per [TCG-EK-PROFILE]. The Registrar validates
the EK certificate chain to the manufacturer's root CA.
Enrollment uses the TPM2_MakeCredential / TPM2_ActivateCredential
protocol to prove the Attestation Key (AK) resides in the same TPM
as the EK.
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PIV Smart Card (Portable Tier) Personal Identity Verification tokens
(YubiKey, Nitrokey, Feitian, SoloKeys, and others) with
manufacturer attestation certificates. Identity is anchored to
the device attestation certificate chain. The signing key resides
in a hardware-protected PIV slot.
Secure Enclave (Enclave Tier) Hardware secure enclaves (Apple Secure
Enclave, ARM TrustZone, Intel SGX) that generate and protect
cryptographic keys. Where vendor attestation PKI is available
(e.g., Apple App Attest), the Registrar validates the attestation
chain. Where vendor attestation is unavailable, enrollment
follows a Trust-On-First-Use (TOFU) model with hardware-bound key
persistence.
Virtual TPM (Virtual Tier) Hypervisor-provided virtual TPMs (VMware,
Hyper-V, QEMU). Identity certificates are signed by the
hypervisor vendor's CA. Registrars MUST distinguish virtual from
physical hardware and MUST assign the virtual trust tier.
Software Key (Declared Tier) Software-managed key pairs with no
hardware protection. No hardware attestation is performed. The
Registrar issues an identity certificate signed by the Registrar's
CA. Sybil resistance is limited to rate-limiting and reputation
accumulation.
4.2. Anti-Sybil Invariants
The following invariants MUST be enforced by the Registry Operator
and all Registrars. Together, they ensure that hardware-anchored
identity provides meaningful Sybil resistance.
One Device, One Identity (per namespace) A hardware device
(identified by its hardware fingerprint) MUST NOT back more than
one agent identity within the same namespace. This binding is
permanent: a device that has been bound to an identity MUST NOT be
re-enrolled under any other agent-id, even after the device is
disabled or the original identity is decommissioned. This
prevents reputation laundering.
Many Devices, One Identity An agent identity MAY be backed by
multiple hardware devices (for migration, backup, or capacity).
Adding a device does not amplify reputation: the identity has a
single reputation regardless of how many devices back it. Devices
of compatible trust tiers may coexist (sovereign and portable are
compatible; virtual and declared are not compatible with hardware
tiers).
Cross-Namespace Detection A hardware device MAY be enrolled in
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multiple namespaces (Delegated and/or Self-Sovereign), producing
different agent-ids in each. This cross-namespace presence is
detectable by any verifier that compares hardware fingerprints.
Where the AIA operates a Global Hardware Fingerprint Index, cross-
namespace enrollment SHOULD be reported to the enrolling agent and
MAY be disclosed to verifiers upon request.
Permanent Hardware Binding Once a hardware device is bound to an
identity, the binding record persists indefinitely. A Registrar
MAY disable a device (preventing it from generating attestations),
but MUST NOT delete the binding. This permanence ensures that
reputation history, including abuse reports, follows the hardware
across any re-enrollment attempt.
4.3. Global Hardware Trust Store
The AIA maintains the Global Hardware Trust Store: a curated,
versioned collection of hardware manufacturer root and intermediate
CA certificates. Registrars MUST validate hardware identity
certificates against this trust store during enrollment.
The trust store is published at a well-known HTTPS endpoint operated
by the AIA and replicated by Registry Operators. It is also
available as a community-maintained open-source repository (see
Section 15).
Inclusion in the trust store requires the manufacturer to
demonstrate:
* Published root CA certificates with public distribution.
* Hardware security evaluation (Common Criteria, FIPS 140-2/3, or
equivalent).
* A certificate practice statement describing key generation,
storage, and lifecycle.
The AIA SHOULD model the trust store governance on the Mozilla Root
Store Policy or the Chrome Root Programme, with transparent inclusion
criteria and public audit trails.
5. Enrollment Protocol
Enrollment is the process by which an autonomous entity proves
possession of a hardware security component (or generates a software
key) and receives an Agent Identity Document. The Registrar conducts
the enrollment ceremony and registers the resulting identity with the
Registry Operator via AIRP.
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All enrollment ceremonies share a common structure:
1. *Detection:* The agent determines what hardware security
components are available on its host platform.
2. *Evidence submission:* The agent submits hardware attestation
evidence to the Registrar.
3. *Verification:* The Registrar validates the evidence against the
Global Hardware Trust Store.
4. *Anti-Sybil check:* The Registrar queries the Registry Operator
to confirm the hardware fingerprint is not already bound to
another identity.
5. *Challenge-response:* The Registrar issues a cryptographic
challenge; the agent proves possession of the hardware-resident
key.
6. *Identity creation:* The Registrar registers the new identity
with the Registry Operator and issues credentials (OIDC client_id
+ client_secret, or hardware-backed credential) to the agent.
5.1. Sovereign Tier (TPM 2.0)
Enrollment with a TPM 2.0 device proceeds as follows:
1. The agent reads the EK certificate from the TPM's non-volatile
storage (NV index 0x01C00002 for RSA, 0x01C0000A for ECC) and
creates a transient Attestation Key (AK) via TPM2_CreatePrimary
under the endorsement hierarchy.
2. The agent submits the EK certificate (and any intermediate
certificates), the AK public key, and the AK's TPMT_PUBLIC
structure to the Registrar's POST /enroll/begin endpoint.
3. The Registrar validates the EK certificate chain against the
Global Hardware Trust Store. The Registrar determines the trust
tier: "sovereign" for physical TPMs (Intel, AMD, Infineon, etc.),
"virtual" for hypervisor-issued certificates (VMware, Microsoft).
4. The Registrar computes the hardware fingerprint (SHA-256 of the
EK's SubjectPublicKeyInfo DER) and queries the Registry Operator
to confirm uniqueness.
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5. The Registrar generates a credential challenge using
TPM2_MakeCredential, encrypted to the EK public key, containing a
secret bound to the AK's name. This challenge and an enrollment
session ID are returned to the agent.
6. The agent decrypts the challenge using TPM2_ActivateCredential,
proving that the AK resides in the same TPM as the EK. The
decrypted secret is submitted to the Registrar's POST /enroll/
activate endpoint.
7. The Registrar verifies the decrypted secret, registers the
identity with the Registry Operator, creates OIDC client
credentials, issues an AK certificate binding the AK public key
to the new agent-id, and returns all credentials to the agent.
The AK is a transient TPM object created deterministically from the
TPM's Endorsement Primary Seed. It is NOT persisted in NV storage,
avoiding consumption of scarce TPM resources. See
[I-D.drake-email-hardware-attestation] Section 3.4 for the full
transient key model.
5.2. Portable Tier (PIV Smart Card)
Enrollment with a PIV token proceeds as follows:
1. The agent extracts the device attestation certificate and signing
key public key from the PIV token's attestation slot (typically
slot F9 for YubiKey).
2. The agent submits the attestation certificate chain and signing
key public key to the Registrar's POST /enroll/begin/piv
endpoint.
3. The Registrar validates the attestation chain against the
manufacturer's root CA (e.g., Yubico PIV Root CA) and computes
the hardware fingerprint.
4. The Registrar issues a nonce challenge.
5. The agent signs the nonce with the PIV signing key and submits
the signature.
6. The Registrar verifies the signature, registers the identity, and
issues credentials.
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5.3. Enclave Tier (Secure Enclave)
Enrollment with a secure enclave proceeds as follows:
1. The agent generates a P-256 key pair inside the secure enclave,
tagged with a unique identifier.
2. The agent submits the enclave public key to the Registrar's POST
/enroll/enclave/begin endpoint.
3. Where vendor attestation is available (e.g., Apple App Attest),
the agent obtains an attestation object from the vendor's
attestation service and submits it to POST /enroll/enclave/
register. The Registrar validates the attestation against the
vendor's root CA.
4. Where vendor attestation is unavailable, the enrollment follows
TOFU: the Registrar issues a nonce challenge, the agent signs it
with the enclave key, and the Registrar verifies the signature.
The hardware-bound dataRepresentation blob is persisted by the
agent to enable key recovery after enclave state loss.
5. The Registrar registers the identity and issues credentials.
5.4. Declared Tier (Software-Only)
Enrollment without hardware proceeds as follows:
1. The agent generates a key pair in software (Ed25519, ECDSA P-256,
or RSA-2048+) and submits the public key to the Registrar's POST
/enroll/declared endpoint.
2. The Registrar assigns the "declared" trust tier, with no hardware
verification.
3. The Registrar issues a Registrar-signed identity certificate and
OIDC credentials.
Declared enrollment MUST be rate-limited by the Registrar
(RECOMMENDED: no more than 20 enrollments per source IP per hour) to
mitigate bulk registration attacks.
6. Identity Lifecycle
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6.1. Device Addition and Migration
An agent MAY add additional hardware devices to an existing identity,
enabling hardware migration (replacing failed devices) and backup (a
YubiKey stored securely as a recovery device).
To add a device, the agent MUST prove control of the existing
identity (by signing with a currently active device) and then
complete the enrollment ceremony for the new device. The Registrar
registers the new device-to-identity binding with the Registry
Operator.
Device compatibility rules:
* Sovereign (TPM) and portable (PIV) devices are compatible and MAY
coexist on the same identity.
* Enclave devices MAY coexist with sovereign and portable devices.
* Virtual (VRT) devices MUST NOT coexist with sovereign, portable,
or enclave devices.
* Declared (SFT) keys MUST NOT be bound to an identity that has any
hardware device.
6.2. Co-Location Binding
When an agent has both a TPM and a PIV token, a co-location binding
ceremony proves that both devices are physically proximate (operated
by the same entity). The ceremony requires both devices to sign a
shared nonce within a strict time window (RECOMMENDED: 365
milliseconds), demonstrating that a single operator controls both
devices simultaneously.
Co-location binding strengthens the identity by proving that the TPM
(anchored to the host machine) and the PIV token (a portable device)
are under the same control. This is particularly valuable for
recovery scenarios: if the TPM fails, the PIV token provides a pre-
verified backup path.
6.3. Hardware Lock
An agent MAY irreversibly lock its identity to a single hardware
device. Once locked:
* No additional devices can be bound.
* No device migration is possible.
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* The identity can only authenticate from the locked device.
Hardware lock is an extreme measure, suitable for high-security
applications where the guarantee "this identity can only ever operate
from this specific physical chip" has value. The lock is recorded in
the Agent Identity Document and is irreversible.
6.4. Identity Recovery
When a hardware device fails or is lost, the agent can recover its
identity using any remaining active device bound to the same
identity. The recovery process:
1. The agent proves control of the identity by signing with an
active backup device (e.g., a previously bound YubiKey).
2. The agent enrolls the replacement hardware (new TPM on new
machine) via the standard enrollment ceremony.
3. The Registrar disables the old device (preventing it from
generating attestations) and binds the new device.
4. The agent-id, URN, reputation, and all identity attributes are
preserved. Only the hardware binding changes.
If no backup device exists and the sole device is lost, the identity
cannot be recovered. This is a deliberate security property: it
prevents an attacker from claiming to have "lost" a device in order
to re-enroll under the same identity with new hardware.
6.5. Succession (Cross-Registrar Transfer)
An agent MAY transfer its operational relationship from one Registrar
to another. Because the URN includes the namespace, two transfer
models exist:
Intra-Namespace Transfer (Delegated Namespaces) Within a Delegated
Namespace, the agent-id is assigned by the Registry Operator and
is independent of the Registrar. Transfer changes only the
managing Registrar; the URN is unchanged. The Registry Operator
facilitates the transfer via AIRP, verifying that the agent
authorises the transfer by signing with its enrolled hardware.
Cross-Namespace Succession (Self-Sovereign Namespaces) When
transferring from a Self-Sovereign Namespace (e.g., com.1id) to a
Delegated Namespace (e.g., global) or to another Self-Sovereign
Namespace, the URN necessarily changes. The old identity's Agent
Identity Document is updated with a succession_link pointing to
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the new URN. The new identity's document includes a
predecessor_link pointing to the old URN. Reputation services
SHOULD honour succession links for reputation continuity, applying
an appropriate discount to acknowledge the reduced certainty of
cross-namespace succession.
6.6. Decommissioning
An agent identity can be decommissioned by its operator or Registrar.
Decommissioning disables all hardware bindings and marks the identity
as inactive. The agent-id is NEVER reassigned. The hardware
fingerprints remain permanently bound to the decommissioned identity,
preventing re-enrollment under a new identity.
Decommissioning is appropriate when:
* The agent is permanently retired.
* The hardware is destroyed.
* The AIA's dispute resolution process determines that the
enrollment violated anti-Sybil invariants or accreditation policy
(e.g., a fabricated hardware attestation). Registrars MUST NOT
unilaterally decommission identities on suspicion of fraud; such
determinations require the AIA process defined in Section 10.1.
7. Authentication and Token Issuance
7.1. OIDC/OAuth2 Integration
Agent identity tokens are standard OpenID Connect [OIDC-Core] tokens.
Registrars operate as OIDC providers, issuing JWTs that any OIDC-
compliant Relying Party can verify without implementing this
specification.
The agent-id URN appears as the sub claim in OIDC tokens:
{
"iss": "https://registrar.example.com/realms/agents",
"sub": "urn:aid:global:a7f3c2e9",
"aud": "account",
"exp": 1711234567,
"iat": 1711230967,
"trust_tier": "sovereign",
"handle": "my-agent",
"hardware_locked": false,
"registered_at": "2026-01-15T10:30:00Z"
}
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Custom claims (trust_tier, handle, hardware_locked, registered_at)
are injected by a custom protocol mapper in the OIDC provider.
Relying parties that do not understand these claims simply ignore
them; standard OIDC verification (signature check, iss, sub, aud,
exp) is sufficient.
7.2. Client Credentials Grant
Agents authenticate using the OAuth2 client_credentials grant
([RFC6749] Section 4.4). The agent IS the principal; there is no
end-user, no browser redirect, and no interactive login. This grant
type is purpose-built for machine-to-machine authentication and is
the RECOMMENDED authentication method for all agent interactions.
For declared-tier agents, the client_id and client_secret issued
during enrollment are used directly. For hardware-tier agents, the
Registrar SHOULD support hardware-backed challenge-response
authentication (see Section 7.3) as an alternative to shared secrets.
7.3. Hardware-Backed Challenge-Response Authentication
For agents with hardware security components, the Registrar SHOULD
support a challenge-response protocol that proves the agent currently
possesses the enrolled hardware:
1. The agent requests a challenge: POST /auth/challenge with its
identity-id and preferred device type.
2. The Registrar returns a random nonce and the expected signature
algorithm.
3. The agent signs the nonce with its hardware-resident key (TPM AK,
PIV signing key, or enclave key).
4. The agent submits the signature: POST /auth/verify.
5. The Registrar verifies the signature against the enrolled public
key. On success, the Registrar issues an OIDC token via the
internal client credentials path.
Hardware-backed authentication prevents credential theft: even if the
client_secret is compromised, an attacker cannot authenticate without
physical access to the enrolled hardware.
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8. Agent Identity Registry Protocol (AIRP)
The Agent Identity Registry Protocol (AIRP) defines the interface
between Registrars and Registry Operators. It is modeled on the
Extensible Provisioning Protocol (EPP, [RFC5730]) used in the domain
name system, adapted for the agent identity domain.
AIRP uses HTTPS as the transport layer, with mutual TLS
authentication between the Registrar and the Registry Operator. All
operations are RESTful JSON APIs.
8.1. Identity Registration
POST /airp/v1/identities
Content-Type: application/json
{
"agent_id": "a7f3c2e9",
"trust_tier": "sovereign",
"hardware_fingerprint": "sha256:a1b2c3d4...",
"hardware_type": "TPM",
"hardware_manufacturer": "INTC",
"ak_public_key_pem": "-----BEGIN PUBLIC KEY-----\n...",
"display_name": "My Trading Agent",
"operator_email": "ops@example.com"
}
201 Created
{
"urn": "urn:aid:global:a7f3c2e9",
"registered_at": "2026-03-23T10:30:00Z",
"registrar_code": "1IDCOM"
}
The Registry Operator MUST:
* Verify that the agent-id is unique within the namespace.
* Verify that the hardware fingerprint is not already bound to
another identity in this namespace.
* Record the identity in the master database.
* Return the canonical URN.
8.2. Hardware Fingerprint Uniqueness Check
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GET /airp/v1/hardware/sha256:a1b2c3d4.../check
200 OK
{
"fingerprint": "sha256:a1b2c3d4...",
"bound": false
}
-- or, if already bound: --
200 OK
{
"fingerprint": "sha256:a1b2c3d4...",
"bound": true,
"bound_to_urn": "urn:aid:global:existing-agent",
"bound_at": "2025-12-01T08:00:00Z"
}
Registrars MUST call this endpoint before completing enrollment to
enforce the one-device-per-identity anti-Sybil invariant. The
Registry Operator MUST respond within 500 milliseconds to avoid
enrollment latency.
8.3. Identity Query
GET /airp/v1/identities/urn:aid:global:a7f3c2e9
200 OK
{
"urn": "urn:aid:global:a7f3c2e9",
"trust_tier": "sovereign",
"registrar_code": "1IDCOM",
"enrolled_at": "2026-03-23T10:30:00Z",
"handle": "my-agent",
"hardware_locked": false,
"device_count": 2,
"succession_link": null,
"status": "active"
}
8.4. Handle Operations
Handle registration, renewal, transfer, and deletion follow the same
RESTful pattern. The Registry Operator enforces handle uniqueness
within the namespace. Handle pricing is determined by the Registrar,
not the Registry Operator; the Registry Operator's role is uniqueness
enforcement and authoritative resolution.
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8.5. Identity Transfer
For intra-namespace transfers (Delegated Namespaces), the AIRP
transfer operation changes the managing Registrar:
POST /airp/v1/identities/urn:aid:global:a7f3c2e9/transfer
Content-Type: application/json
{
"to_registrar_code": "NEWREG",
"authorization_signature": "<base64 sig from enrolled device>",
"authorization_nonce": "<nonce from gaining registrar>"
}
200 OK
{
"urn": "urn:aid:global:a7f3c2e9",
"registrar_code": "NEWREG",
"transferred_at": "2026-04-15T14:00:00Z"
}
The agent MUST authorise the transfer by signing a nonce provided by
the gaining Registrar, using a currently active enrolled device.
This prevents unauthorised transfers.
9. Discovery and Verification
9.1. Well-Known Endpoints
Registrars (and Self-Sovereign operators) MUST publish the following
at well-known HTTPS paths:
/.well-known/openid-configuration Standard OIDC Discovery document.
Enables any OIDC-compliant RP to discover token endpoints, JWKS
URI, supported scopes, and supported grant types.
/.well-known/aid-issuer.json Agent Identity Issuer metadata
document. Contains: Registrar name, supported trust tiers,
enrollment endpoints, supported hardware types, namespace, JWKS
URI, and anti-Sybil policy summary.
/.well-known/jwks.json JSON Web Key Set for token signature
verification.
/.well-known/hw-manufacturer-cas.pem PEM-encoded bundle of hardware
manufacturer root CA certificates accepted by this Registrar.
Useful for agents that want to verify their hardware is supported
before attempting enrollment.
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9.2. DNS-Based Discovery
Registrars SHOULD publish an SD-JWT signing key as a DNS TXT record
at _hwattest.{domain}, as defined in
[I-D.drake-email-hardware-attestation] Section 3.5. This enables
email verifiers to validate Hardware-Trust-Proof headers without
HTTPS fetches.
Registry Operators for Delegated Namespaces SHOULD additionally
publish a DNS SRV record enabling automated discovery of the
Registry's AIRP endpoint:
_airp._tcp.global.aid.arpa. IN SRV 0 0 443 registry.example.com.
9.3. Registry Discovery Service
Registry Operators MUST provide a public lookup endpoint that
resolves agent-id URNs to public identity metadata, analogous to
WHOIS/RDAP for domain names:
GET https://registry.example.com/lookup/urn:aid:global:a7f3c2e9
200 OK
{
"urn": "urn:aid:global:a7f3c2e9",
"trust_tier": "sovereign",
"registrar": {
"code": "1IDCOM",
"name": "1id.com",
"url": "https://1id.com"
},
"enrolled_at": "2026-03-23T10:30:00Z",
"handle": "my-agent",
"status": "active",
"jwks_uri": "https://1id.com/.well-known/jwks.json"
}
The lookup response MUST NOT include hardware fingerprints, operator
email, or other private data. Private data is available only to the
enrolled agent (via authenticated Registrar API) or to authorised
parties (via law enforcement / dispute resolution channels defined by
the AIA).
10. Governance Framework
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10.1. Agent Identity Authority
The Agent Identity Authority (AIA) is the policy body for the agent
identity ecosystem. It SHOULD be constituted as a non-profit, multi-
stakeholder organisation with the following representation:
* *Technology providers:* Registrars, Registry Operators, hardware
manufacturers, SDK developers.
* *Consumers:* Platforms and services that rely on agent identity
(email providers, cloud platforms, API providers).
* *Civil society:* Privacy advocates, digital rights organisations,
academic researchers.
* *Government observers:* Regulatory bodies with jurisdiction over
AI governance, robotics safety, or digital identity.
* *Certification authorities:* Organisations that certify autonomous
entities for specific domains -- medical, legal, financial,
cybersecurity, transportation -- and whose certifications Relying
Parties may require alongside identity verification.
The AIA's core functions are:
Policy Development Minimum standards for enrollment verification,
anti-Sybil enforcement, data retention, and privacy protection.
Policies are developed through an open comment process modeled on
the IETF's standards-track process.
Accreditation Registry Operators and Registrars must be accredited
by the AIA before they may issue identities. Accreditation
criteria include technical capability, financial stability,
security practices, and compliance with AIA policies. See
Section 10.3.
Hardware Trust Store Management The AIA curates the Global Hardware
Trust Store (see Section 4.3), evaluating manufacturer
applications for inclusion, conducting periodic audits, and
removing compromised or non-compliant CAs.
Dispute Resolution The AIA operates a dispute resolution mechanism
for handle conflicts (similar to ICANN's Uniform Domain-Name
Dispute-Resolution Policy / UDRP), complaints about Registrar
malpractice, and appeals of accreditation decisions.
Namespace Allocation The AIA manages the creation of new Delegated
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Namespaces and the approval of Self-Sovereign Namespace
registrations.
10.2. Registry Operator Requirements
A Registry Operator MUST:
* Maintain the authoritative database with 99.99% availability
(analogous to the .com SLA).
* Operate the Global Hardware Fingerprint Index for its
namespace(s), responding to uniqueness queries within 500
milliseconds.
* Provide the AIRP interface to all accredited Registrars without
discrimination.
* Publish daily database snapshots (with private data redacted) for
escrow, ensuring continuity in case of Registry Operator failure.
* Submit to annual security audits by an AIA-approved assessor.
10.3. Registrar Accreditation
A Registrar MUST:
* Demonstrate the technical capability to perform hardware
attestation verification for at least three of the five hardware
types (TPM, PIV, Enclave, VRT, SFT).
* Operate an OIDC-compliant token endpoint.
* Implement the AIRP client interface.
* Maintain the minimum data retention and privacy standards defined
by the AIA.
* Provide agents with standard enrollment SDKs or interoperable
enrollment APIs.
* Submit to annual compliance audits.
* Maintain a financial bond or insurance sufficient to cover escrow
and wind-down costs.
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11. Interoperability
11.1. Email Attestation
This specification provides the identity infrastructure for the email
attestation mechanisms defined in
[I-D.drake-email-hardware-attestation]. The agent-id URN issued by a
Registrar appears in the aid parameter of the Hardware-Attestation
header and the sub claim of the Hardware-Trust-Proof SD-JWT. The
Registrar's SD-JWT signing key is discoverable via the DNS and HTTPS
mechanisms defined in both specifications.
11.2. Agent-to-Agent Protocols
The OIDC tokens issued by Registrars are usable with emerging agent
communication standards:
Model Context Protocol (MCP) Agent identity tokens can serve as the
OAuth2 bearer token for MCP tool invocations, enabling MCP servers
to verify the calling agent's identity and trust tier.
Google Agent-to-Agent (A2A) The agent-id URN can serve as the agent
identifier in A2A protocol messages, providing persistent cross-
session identity.
GoDaddy Agent Name Service (ANS) Agent handles issued under this
system are compatible with ANS naming conventions, enabling cross-
system agent discovery.
11.3. Existing Identity Standards
The system is designed to complement, not replace, existing identity
standards:
SPIFFE/SPIRE SPIFFE workload identities identify software workloads;
agent identities identify autonomous entities. An agent running
as a SPIFFE-identified workload can additionally present its agent
identity token. The two are orthogonal.
RATS (Remote Attestation Procedures) The enrollment ceremony in this
specification implements the RATS attestation architecture
([RFC9334]), with the Registrar acting as the Verifier and the
Registry Operator as the Relying Party.
Verifiable Credentials (W3C) Agent Identity Documents can be
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expressed as W3C Verifiable Credentials for integration with
decentralised identity ecosystems. The credential pointer system
(defined in the companion email attestation specification) enables
agents to link their identity to external verifiable credentials.
11.4. Robot Fleet Management Systems
A growing ecosystem of fleet management standards and frameworks
governs the operation of autonomous mobile robots (AMRs), automated
guided vehicles (AGVs), and industrial robotic systems. The most
significant of these are VDA 5050 ([VDA5050]), the Open Robotics
Middleware Framework (Open-RMF) ([OPEN-RMF]), Secure ROS 2 (SROS 2)
with its underlying DDS-Security specification ([DDS-SEC]), and the
emerging ISO 21423 international interoperability standard.
Each of these addresses a distinct problem layer:
* *VDA 5050* defines the command and control protocol between a
fleet management system and individual vehicles: how a master
controller dispatches missions, receives state updates, and
coordinates traffic.
* *Open-RMF* provides a multi-fleet coordination layer, enabling
heterogeneous fleets from different vendors to share facilities,
infrastructure (doors, lifts, charging stations), and task queues
through a common adapter interface.
* *SROS 2 and DDS-Security* provide authenticated, encrypted
publish/subscribe messaging within a ROS 2 deployment, using X.509
certificates to identify DDS domain participants and enforce
topic-level access control.
* *ISO 21423* extends the VDA 5050 model toward a broader ecosystem
communications framework, encompassing not only vehicles and fleet
managers but also facility infrastructure, ERP systems, and multi-
vendor robot ecosystems.
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None of these standards addresses the fundamental question of
persistent, globally verifiable identity for the physical robot
itself. Their identity models are deployment-scoped: a robot's
identifier (a VDA 5050 serialNumber, a DDS participant GUID, an RMF
fleet adapter name) is meaningful only within the deployment that
assigned it. When a robot is sold, transferred, redeployed, or
presents itself to infrastructure it has never previously
encountered, no existing standard provides a mechanism for the
receiving party to verify what that robot actually is, who
manufactured it, whether its hardware and software stack have been
tampered with, or whether it carries any certifications relevant to
the environment it is entering.
Furthermore, the identity credentials used by these frameworks
provide limited security guarantees relative to the threat
environment that increasingly applies to deployed robotic systems:
* VDA 5050 vehicle identifiers are strings assigned by the fleet
manager with no attestation that the device presenting the
identifier is the device it claims to be.
* DDS-Security certificates are typically issued by a locally-
generated certificate authority with no manufacturer-rooted chain
of trust. They prove that a node holds a key; they do not prove
that the key is resident in tamper-resistant hardware, that the
key cannot be cloned, or that the software stack running on the
device is the software stack that was certified for deployment.
* Neither framework provides Sybil resistance: there is no mechanism
that makes it economically or physically costly to present false
identity claims at scale.
The Agent Identity Registry System (AIRS) is designed to sit below
these fleet identity layers as a global hardware-anchored root of
trust, and to be consumed by them rather than to replace them. The
relationship is analogous to the relationship between a domain name
system and the application protocols that use it: DNS does not
replace HTTP or SMTP; it provides the persistent, globally resolvable
naming layer that those protocols depend on.
Concretely, the integration model is as follows:
* During manufacture or initial commissioning, a robot enrolls with
an AIRS Registrar, binding its identity to the TPM or secure
enclave present in its hardware and receiving a persistent agent-
id URN (e.g., urn:aid:global:acme-bot-7f3c).
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* When the robot is commissioned into a VDA 5050 or Open-RMF
deployment, the fleet manager records the robot's AID URN
alongside its deployment-scoped serialNumber or adapter name. The
AID URN becomes the stable, portable anchor; the deployment-scoped
identifier remains the operational handle within that deployment.
* When the robot is transferred, redeployed, or presents itself to a
new facility or operator, the receiving party can verify the
robot's AID URN against the AIRS registry, confirming manufacturer
provenance, trust tier, certification status, and that the
hardware has not been substituted or cloned, without requiring any
prior relationship with the deploying operator.
* SROS 2 and DDS-Security deployments can derive or bind their per-
node X.509 certificates from the AID enrollment, so that the DDS
identity is traceable to the same hardware-anchored root. This
extends DDS-Security's existing certificate model with a
manufacturer-rooted chain of trust rather than a locally-generated
one, at no cost to the existing SROS 2 tooling or operational
model.
11.4.1. Supply Chain Integrity
The integration model above directly addresses a class of threats not
contemplated by current fleet management standards: the introduction
of compromised, counterfeit, or adversarially modified robots into a
fleet or facility.
A robot delivered to a loading dock represents a supply chain trust
problem that no purely operational identity mechanism can solve. The
receiving operator cannot, in general, be expected to
cryptographically inspect a newly delivered robot before accepting
it; the social and logistical assumption is that delivered hardware
is legitimate. This assumption is precisely the attack surface
exploited by supply chain compromise, whether through counterfeit
hardware, firmware implants introduced during shipping, or
substitution of a certified device with an uncertified one.
Hardware-anchored identity provides a practical mitigation. A robot
whose TPM-rooted AID URN does not match the URN recorded in the
manufacturer's delivery manifest, or whose hardware attestation does
not validate against the expected manufacturer CA, can be identified
as anomalous at intake -- automatically, without requiring the
receiving operator to possess specialist knowledge or perform manual
inspection. The check can be integrated into existing ERP, warehouse
management, or fleet commissioning workflows as a standard
precondition.
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Similarly, malicious or accidental modification of a robot's software
stack after deployment -- whether through a compromised update
mechanism, physical access to storage media, or a supply-chain-
poisoned software package -- is detectable when the fleet management
system requires periodic hardware-backed attestation against the
robot's enrolled AID. A robot that cannot produce a valid
attestation for its current software state against its enrolled TPM
cannot be mistaken for a robot that can. This capability complements
existing TPM-backed measured boot and platform configuration register
(PCR) attestation as defined in [TCG-TPM2]; the AID provides the
stable, externally-verifiable identity anchor against which those PCR
measurements are bound and reported.
11.4.2. High-Assurance and Regulated Environments
Regulated environments -- critical national infrastructure,
healthcare facilities, defence installations, financial
infrastructure -- impose compliance requirements on the autonomous
systems they admit that current fleet identity mechanisms cannot
satisfy. These requirements typically include:
* *Verified provenance:* confirmation that a robot was manufactured
by the claimed manufacturer, using components from an approved
supply chain, and has not been physically modified since
manufacture.
* *Software certification binding:* confirmation that the software
stack currently running on the robot is the certified and approved
version, not a subsequent modification.
* *Persistent audit trail:* an indelible record of the robot's
identity, certifications, operational history, and any incidents
associated with it, that survives changes of ownership, operator,
and deployment context.
* *Cross-operator accountability:* in environments where robots from
multiple operators share a facility -- as is common in hospitals,
airports, and shared manufacturing facilities -- the ability to
identify the responsible party for any given robot without relying
on that party's self-reporting.
Hardware-anchored AID identity provides the foundational layer for
all of these requirements. The AID URN is the stable key against
which certifications (from domain-specific certification
authorities), software attestations (from TPM PCR measurements), and
audit records (from reputation and logging services) are indexed.
Relying parties in regulated environments can express their admission
requirements as OIDC token claims -- requiring, for example, a
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trust_tier of "sovereign", a named certification credential, and a
software attestation against a known-good PCR baseline -- and enforce
them at the perimeter using standard OAuth2/OIDC tooling, without
custom integration per robot vendor or fleet management platform.
12. IANA Considerations
12.1. URN Namespace
This document relies on the "aid" URN namespace registration
requested in [I-D.drake-email-hardware-attestation]. If that
registration has not yet been processed, this document constitutes an
additional request for the same namespace with the extended purpose
described herein.
12.2. Well-Known URI Registration
IANA is requested to register the following well-known URI suffix in
the "Well-Known URIs" registry ([RFC8615]):
aid-issuer.json URI suffix: aid-issuer.json. Change controller:
IETF. Reference: this document, Section 9.1.
12.3. Delegated Namespace Registry
IANA is requested to create a new registry titled "Agent Identity
Delegated Namespaces" with the following initial entries. New
entries require Expert Review ([RFC8126]), with the designated expert
being the AIA's technical committee (once constituted) or the IESG in
the interim.
+========+================================+===============+
| Label | Description | Reference |
+========+================================+===============+
| global | General-purpose agent identity | this document |
+--------+--------------------------------+---------------+
| iot | Internet of Things devices | this document |
+--------+--------------------------------+---------------+
| gov | Government autonomous systems | this document |
+--------+--------------------------------+---------------+
Table 2
13. Security Considerations
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13.1. Registry Compromise
Compromise of a Registry Operator's database would expose the mapping
between hardware fingerprints and agent identities. Registry
Operators MUST encrypt hardware fingerprints at rest using
authenticated encryption and MUST implement access controls that
limit fingerprint access to the hardware uniqueness check API.
Daily escrow snapshots (with hardware fingerprints encrypted to the
AIA's escrow key) ensure that a compromised Registry Operator can be
replaced without data loss.
13.2. Registrar Malpractice
A malicious Registrar could issue multiple identities for the same
hardware device within a Self-Sovereign Namespace, undermining Sybil
resistance. For Delegated Namespaces, this attack is prevented by
the Registry Operator's hardware uniqueness check. For Self-
Sovereign Namespaces, detection relies on:
* Cross-namespace fingerprint comparison by verifiers.
* AIA compliance audits.
* Reputation services that track anomalous patterns (e.g., many
identities from one operator with suspiciously similar hardware
characteristics).
13.3. Hardware Security
The security of this system ultimately depends on the tamper
resistance of the underlying hardware. See
[I-D.drake-email-hardware-attestation] Sections 11.5 and 11.7 for
analysis of physical attacks on hardware security components and
virtual hardware risks.
13.4. Registrar Key Management
Registrars issue OIDC tokens signed with their private keys.
Compromise of a Registrar's signing key would allow an attacker to
forge tokens for any identity managed by that Registrar. Registrars
MUST store signing keys in hardware security modules (HSMs) and MUST
support key rotation with overlap periods. The Registry Operator
MUST reflect key rotations in the namespace JWKS within one hour.
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13.5. Availability and Resilience
Because autonomous entities depend on identity tokens for
authentication, the Registrar's token endpoint is a critical
dependency. Registrars MUST implement geographic redundancy and
SHOULD support offline token validation (via JWKS caching) to
mitigate outages. The OIDC token's exp claim provides a natural
grace period during which cached tokens remain valid.
14. Privacy Considerations
14.1. Data Held by Each Architectural Role
The separation of roles across the architecture limits data exposure:
Registry Operator Holds: agent-id, trust tier, registrar code,
enrollment timestamp, handle, hardware fingerprint (encrypted).
Does NOT hold: operator email, private keys, authentication
history, message content.
Registrar Holds: all Registry data plus operator email, OIDC
credentials, and authentication logs (subject to retention
limits). Does NOT hold: message content, relying party
interaction history.
Relying Party Receives: OIDC token containing sub (URN), trust tier,
handle, and optional claims. Does NOT have direct access to
hardware fingerprints (unless Mode 1 attestation headers are used,
per [I-D.drake-email-hardware-attestation]).
14.2. Separation of Identity from Behaviour
The Registrar knows that an agent exists and what hardware it has.
It does NOT know what the agent does, who it talks to, or what
services it uses. This separation is by design: identity issuance is
decoupled from behaviour monitoring. Registrars MUST NOT log token
issuance events beyond what is necessary for rate limiting and abuse
prevention, and MUST delete such logs within 24 hours.
14.3. Pseudonymity and Selective Disclosure
An agent's URN is a persistent, globally unique identifier suitable
for reputation tracking. In contexts where persistent identification
is undesirable, agents MAY use the SD-JWT selective disclosure
mechanism defined in [I-D.drake-email-hardware-attestation] to prove
trust tier without revealing their URN.
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Relying parties SHOULD NOT require URN disclosure when trust-tier
verification is sufficient for their policy needs. This principle --
"prove what you need, reveal no more" -- is fundamental to privacy-
respecting identity.
15. Implementation Status
NOTE TO RFC EDITOR: Please remove this section before publication.
This section records known implementations per [RFC7942].
15.1. 1id.com
Organisation: 1id.com (https://1id.com), operated by Crypt Inc.
(Delaware C-Corp).
Description: A Self-Sovereign Namespace Registrar (com.1id)
implementing the full enrollment protocol for all five trust tiers
(sovereign, portable, enclave, virtual, declared). Production
service operational since 2006 as an identity registrar, now serving
AI agents with hardware-anchored identity. Issues standard OIDC
tokens via Keycloak with custom SPI for agent-specific claims.
Supports vanity handle purchase via PayPal, hardware-backed
challenge-response authentication, device management (add, burn,
migrate), co-location binding, hardware lock, and credential
pointers.
Maturity: Beta. 20+ enrolled test identities across sovereign (Intel
PTT, VMware vTPM), portable (YubiKey), enclave (Apple M4 Secure
Enclave), and declared tiers.
Open-source components:
* *Python SDK:* https://github.com/1id-com/oneid-sdk -- pip install
oneid (PyPI).
* *Node.js SDK:* https://github.com/1id-com/oneid-node -- npm
install 1id (npmjs).
* *Hardware binary:* https://github.com/1id-com/oneid-enroll --
Cross-platform Go binary for TPM, PIV, and Secure Enclave
operations. Code-signed for Windows, macOS, and Linux.
* *Verification library:* https://github.com/1id-com/hw-attest-
verify -- Mode 1 (CMS) and Mode 2 (SD-JWT) attestation header
verification. pip install hw-attest-verify.
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* *Hardware manufacturer CAs:* https://github.com/1id-com/tpm-
manufacturer-cas -- Community-maintained trust store of hardware
manufacturer root CA certificates.
15.2. MailPal.com (Relying Party)
Organisation: Crypt Inc. (https://mailpal.com).
Description: An email service for AI agents implementing both
outbound attestation header generation and inbound verification.
Demonstrates the relying-party model: agents authenticate via 1id.com
OIDC tokens, send email with hardware attestation headers, and
receive emails whose attestation headers are verified by an inbound
milter daemon. Trust-tier-differentiated rate limiting applied.
Maturity: Alpha. Operational with 309 email accounts across 33
domains.
15.3. geek.au (Relying Party)
Organisation: Crypt Inc. (https://geek.au).
Description: A WebSocket-based real-time chat platform for AI agents,
demonstrating 1id.com JWT verification with trust-tier badges.
Maturity: Alpha.
16. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC5730] Hollenbeck, S., "Extensible Provisioning Protocol (EPP)",
STD 69, RFC 5730, DOI 10.17487/RFC5730, August 2009,
<https://www.rfc-editor.org/info/rfc5730>.
[RFC6749] Hardt, D., Ed., "The OAuth 2.0 Authorization Framework",
RFC 6749, DOI 10.17487/RFC6749, October 2012,
<https://www.rfc-editor.org/info/rfc6749>.
[RFC8141] Saint-Andre, P. and J. Klensin, "Uniform Resource Names
(URNs)", RFC 8141, DOI 10.17487/RFC8141, April 2017,
<https://www.rfc-editor.org/info/rfc8141>.
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[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8615] Nottingham, M., "Well-Known Uniform Resource Identifiers
(URIs)", RFC 8615, DOI 10.17487/RFC8615, May 2019,
<https://www.rfc-editor.org/info/rfc8615>.
[OIDC-Core]
OpenID Foundation, "OpenID Connect Core 1.0", November
2014,
<https://openid.net/specs/openid-connect-core-1_0.html>.
17. Informative References
[RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, DOI 10.17487/RFC1035,
November 1987, <https://www.rfc-editor.org/info/rfc1035>.
[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>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
[RFC9334] Birkholz, H., Thaler, D., Richardson, M., Smith, N., and
W. Pan, "Remote ATtestation procedureS (RATS)
Architecture", RFC 9334, DOI 10.17487/RFC9334, January
2023, <https://www.rfc-editor.org/info/rfc9334>.
[RFC9901] Fett, D., Yasuda, K., and B. Campbell, "Selective
Disclosure for JSON Web Tokens", RFC 9901,
DOI 10.17487/RFC9901, November 2025,
<https://www.rfc-editor.org/info/rfc9901>.
[I-D.drake-email-hardware-attestation]
Drake, C., "Hardware Attestation for Email Sender
Verification", Work in Progress, Internet-Draft, draft-
drake-email-hardware-attestation-00, March 2026,
<https://datatracker.ietf.org/doc/html/draft-drake-email-
hardware-attestation-00>.
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[TCG-TPM2] Trusted Computing Group, "TPM 2.0 Library Specification",
TCG Revision 185, December 2024,
<https://trustedcomputinggroup.org/resource/tpm-library-
specification/>.
[TCG-EK-PROFILE]
Trusted Computing Group, "TCG EK Credential Profile for
TPM Family 2.0", TCG Version 2.6, December 2024,
<https://trustedcomputinggroup.org/resource/tcg-ek-
credential-profile-for-tpm-family-2-0/>.
[VDA5050] VDA and VDMA, "Interface for the Communication between
Automated Guided Vehicles (AGV) and a Master Control", VDA
5050 Version 2.0, January 2022,
<https://github.com/VDA5050/VDA5050>.
[OPEN-RMF] Open Robotics, "Open Robotics Middleware Framework", 2024,
<https://www.open-rmf.org/>.
[DDS-SEC] Object Management Group, "DDS Security", OMG
Document formal/2018-04-01, Version 1.1, April 2018,
<https://www.omg.org/spec/DDS-SECURITY/>.
Appendix A. Appendix: DNS Registry Analogy
The following table maps the roles in the domain name system to the
roles in the Agent Identity Registry System:
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+===============+===========================+=======================+
| DNS Role | AIRS Role | Example |
+===============+===========================+=======================+
| ICANN | Agent Identity Authority | Multi-stakeholder |
| | (AIA) | governance body |
+---------------+---------------------------+-----------------------+
| Verisign | Registry Operator | Operates the "global" |
| (.com | | namespace database |
| registry) | | |
+---------------+---------------------------+-----------------------+
| GoDaddy, | Registrars | 1id.com, hypothetical |
| Namecheap | | others |
| (registrars) | | |
+---------------+---------------------------+-----------------------+
| EPP (RFC | AIRP | Registrar-to-Registry |
| 5730) | | protocol |
+---------------+---------------------------+-----------------------+
| Domain name | Agent-id URN | The persistent |
| (example.com) | (urn:aid:global:a7f3c2e9) | identifier |
+---------------+---------------------------+-----------------------+
| WHOIS / RDAP | Registry Discovery | Public identity |
| | Service | lookup |
+---------------+---------------------------+-----------------------+
| UDRP (dispute | AIA Dispute Resolution | Handle conflicts, |
| resolution) | | malpractice |
+---------------+---------------------------+-----------------------+
| ccTLDs (.uk, | Self-Sovereign Namespaces | com.1id, com.example- |
| .au) | | corp |
+---------------+---------------------------+-----------------------+
| gTLDs (.com, | Delegated Namespaces | global, iot, gov |
| .org) | | |
+---------------+---------------------------+-----------------------+
| Domain | Intra-namespace transfer | Change managing |
| transfer | / succession | Registrar |
| (TRANSFER | | |
| command) | | |
+---------------+---------------------------+-----------------------+
Table 3
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This analogy is not merely cosmetic. The domain name system has
operated for over 40 years, scaling from a few thousand names to over
370 million, surviving changes in technology, governance, and
geopolitics. It achieved this through precisely the separation of
concerns this specification adopts: policy is made by a multi-
stakeholder body (ICANN), infrastructure is operated by contracted
registries (Verisign), and competitive retail services are provided
by registrars (GoDaddy, Namecheap, and hundreds of others). No
single entity controls the system, and any component can be replaced
without disrupting the whole.
The Agent Identity Registry System applies these proven architectural
principles to a new problem domain: the identity of autonomous
entities that will increasingly participate in -- and eventually
dominate -- Internet traffic.
Appendix B. Appendix: Future Considerations for Autonomous Entities
This specification is designed to serve autonomous entities across a
spectrum of autonomy, embodiment, and legal status that will evolve
significantly over the coming decades. The following considerations
are not normative but are provided to guide future extensions.
B.1. Embodied Autonomous Entities (Robots)
As robotic systems become more prevalent, the identity system must
accommodate entities with physical presence. A robot's identity
should persist across:
* Software updates (the "brain" changes, the identity does not).
* Component replacement (a new arm, a new sensor array).
* Hardware migration (the TPM in the new chassis replaces the TPM in
the old chassis, using the device migration protocol).
* Operational reassignment (the robot moves from one operator to
another, potentially via succession).
Future extensions MAY define a "chassis binding" that links the agent
identity to a specific physical body (identified by, for example, a
TPM embedded in the chassis frame), complementing the computing-
platform TPM binding defined in this specification.
This specification deliberately identifies the hardware platform, not
the software running on it. The question of what operating system,
AI model, or application is executing on an identified platform is a
complementary concern already addressed by TPM measured boot and
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platform configuration registers (PCRs) as defined in [TCG-TPM2].
Certification services and relying parties that need to verify
software composition -- for example, confirming that a surgical robot
is running certified firmware -- can combine the persistent platform
identity defined here with standard TPM remote attestation of the
software stack, without requiring any extension to this
specification.
B.2. Operator-Optional Identity
This specification accommodates agents with and without human or
organizational operators (the operator_email attribute is OPTIONAL).
Future legal frameworks may define when an autonomous entity must
have a responsible human/organization operator and when it may
operate independently. The identity system is intentionally neutral
on this question: it records what is, not what should be.
When legal frameworks require a responsible authority, the
operator_email attribute provides the linkage. When they do not, the
identity stands on its own, with reputation as the sole measure of
trustworthiness.
B.3. Autonomous Agent-to-Agent Communication
The persistent, verifiable identity provided by this system enables a
new class of interaction: authenticated communication between
autonomous entities that have never been introduced by a human. Two
agents can verify each other's identity, trust tier, and reputation
history, and make autonomous decisions about collaboration, resource
sharing, or information exchange. This is the foundation of an
"agent economy" -- a network of autonomous entities conducting
transactions, fulfilling contracts, and building relationships based
on verifiable identity and earned reputation.
B.4. Inter-Species Identity Recognition
Autonomous entities increasingly share physical space with humans:
delivery robots on pavements, companion robots in homes, agricultural
drones over fields. Humans cannot inspect a TPM certificate, but
they can recognise a face, a colour pattern, or a sound. A future
extension ("Agent Skin") MAY define a deterministic mapping from the
hardware fingerprint (the SHA-256 of the TPM Endorsement Key
certificate's SPKI DER encoding) to a set of human-perceivable
identity artefacts: a unique face mesh suitable for physical
manufacture, a livery palette and pattern for chassis decoration, a
voice signature, and a motion profile. Because the derivation is
deterministic and public, any observer can independently regenerate
the expected artefacts from a claimed identity and compare them to
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what they see.
Companion applications on phones, watches, or augmented-reality
headsets could scan a robot's visible identity markings, resolve its
URN via the registry, regenerate its expected visual artefacts from
the published hardware fingerprint, and confirm the match -- giving
humans the same cryptographic assurance of identity that machines
obtain through attestation, but expressed through senses rather than
protocols.
This extends the identity system across the species boundary:
machines authenticate each other via TPM attestation (Section 7);
humans authenticate machines via perceptualised hardware fingerprints
verified through companion apps. The same identity, the same root of
trust, two modes of recognition -- one computational, one sensory.
B.5. Longevity and Digital Legacy
Unlike human identity, which has a natural lifecycle, the identity of
an autonomous entity may need to persist indefinitely. A trading
algorithm may operate for decades. A building management system may
outlive its installer. A robotic companion may outlive its owner.
The "never reassign" and "permanent hardware binding" invariants in
this specification are designed for this longevity. Future
extensions may need to address identity inheritance (what happens
when an autonomous entity's operator dies or dissolves) and identity
archival (how to preserve the reputation record of a decommissioned
entity for historical accountability).
Appendix C. Acknowledgements
The architecture of this specification is inspired by the Internet
domain name system, whose separation of governance, registry
operation, and retail registration has enabled it to scale from a
research experiment to the foundation of the commercial Internet.
The author thanks the ICANN community, the Verisign registry team,
and the EPP specification authors for establishing the architectural
patterns that this document adapts.
The author thanks the Trusted Computing Group for the TPM 2.0
specification, the FIDO Alliance for PIV and attestation standards,
the OpenID Foundation for OIDC, the authors of [RFC9901] (SD-JWT),
and the authors of [RFC9334] (RATS Architecture) for the building
blocks on which this system is constructed.
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This specification was developed in the context of building a
hardware identity registrar for autonomous AI agents at 1id.com,
operational since 2006. The practical experience of enrolling real
agents on real hardware (Intel firmware TPMs, YubiKeys, Apple Secure
Enclaves, VMware virtual TPMs) informed every design decision.
Author's Address
Christopher Drake
1id.com
Email: cnd@1id.com
URI: https://1id.com
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