Remote Posture Assessment for Systems, Containers, and Applications at Scale
draft-ietf-rats-posture-assessment-04
| Document | Type | Active Internet-Draft (rats WG) | |
|---|---|---|---|
| Authors | Kathleen Moriarty , Monty Wiseman , A.J. Stein , Chandra Nelogal | ||
| Last updated | 2026-04-08 | ||
| Replaces | draft-moriarty-rats-posture-assessment | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | (None) | ||
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draft-ietf-rats-posture-assessment-04
Network Working Group K. M. Moriarty
Internet-Draft Transforming Information Security LLC
Intended status: Standards Track M. Wiseman
Expires: 10 October 2026 Beyond Identity
A.J. Stein
C. Nelogal
Dell
8 April 2026
Remote Posture Assessment for Systems, Containers, and Applications at
Scale
draft-ietf-rats-posture-assessment-04
Abstract
This document establishes an architectural pattern whereby
Attestation Results could be produced for a complete set of
benchmarks or controls that are defined and grouped by an external
entity, eliminating the need to convey individual Evidence items for
each item within a benchmark or control framework. This document
establishes a pattern to list sets of benchmarks and controls within
CWT and JWT formats for use as an Entity Attestation Token (EAT).
While the discussion below pertains mostly to TPM, other Roots of
Trust such as TCG DICE and non-TCG defined components will also be
included.
About This Document
This note is to be removed before publishing as an RFC.
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assessment/.
Discussion of this document takes place on the Remote ATtestation
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Status of This Memo
This Internet-Draft is submitted in full conformance with the
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This Internet-Draft will expire on 10 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
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions and Definitions . . . . . . . . . . . . . . . . . 4
3. Posture Assessment Scenarios . . . . . . . . . . . . . . . . 4
4. Policy and Measurement Set Definitions . . . . . . . . . . . 6
5. Supportability and Re-Attestation . . . . . . . . . . . . . . 7
6. Configuration Sets . . . . . . . . . . . . . . . . . . . . . 8
7. Remediation . . . . . . . . . . . . . . . . . . . . . . . . . 8
8. Security Considerations . . . . . . . . . . . . . . . . . . . 9
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9
9.1. Reuse of CBOR and JSON Web Token (CWT and JWT) Claims
Registries . . . . . . . . . . . . . . . . . . . . . . . 9
9.2. CWT and JWT Claims Registered by This Document . . . . . 9
9.3. Additions to the JWT and CWT registries requested . . . . 10
9.4. MPS (Measurement or Policy Set) Claim . . . . . . . . . . 10
10. Appendix A – Extended Claims Table with RoT Variants . . . . 11
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10.1. A.1 – Chained Attestation and Measurement Exposure Across
Hardware Roots of Trust . . . . . . . . . . . . . . . . 11
10.2. A.2 – Extended Claims Table with DICE, Apple Secure
Enclave, OpenTitan, and Amazon Nitro . . . . . . . . . . 12
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
11.1. Normative References . . . . . . . . . . . . . . . . . . 15
11.2. Informative References . . . . . . . . . . . . . . . . . 16
Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
Posture assessment has long been desired, but has been difficult to
achieve due to complexities of customization requirements at each
organization. By using policy and measurement sets that may be
offered at various assurance levels, local appraisal of Evidence can
be performed to continuously assess compliance.
For example, the Trusted Computing Group's Trusted Platform Module
(TPM) format and assessment method can provide this kind of
compliance. This and other methods employ a secured log for
transparency on the results of the appraised Evidence against
Reference Values.
In order to support continuous monitoring of posture assessment and
integrity in an enterprise or large data center, local appraisal and
remediation are useful to reduce load on the network and remote
resources. This is currently done today in measured boot mechanisms.
It is useful to be able to share these results in order to gain a big
picture view of the governance, risk, and compliance posture for a
network.
As such, communicating a summary result as Evidence including a link
to supporting logs within an Entity Attestation Token (EAT) profile
[I-D.ietf-rats-eat] provides a way to accomplish that goal.
This level of integration, which includes the ability to remediate,
makes posture assessment through remote attestation achievable for
organizations of all sizes. This is enabled through integration with
existing toolsets and systems, built as an intrinsic capability.
The measurement and policy grouping results summarized in an EAT
profile may be provided by the vendor or by a neutral third party,
acting as a Reference Value Provider, to enable ease of use and
consistent implementations.
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The local system or server host, acting as a local Verifier, performs
the appraisal of posture Evidence and remediation. This provides
simpler options to enable posture assessment at selected levels by
organizations without the need to have in-house expertise.
The measurement and policy sets may also be customized, but not
necessary to achieve posture assessment to predefined options.
This document describes a method to use existing remote attestation
formats and protocols. The method described allows for defined
profiles of policies, benchmarks, and measurements for specific
assurance levels. This provides transparency on posture assessment
results summarized as Attestation Results.
2. Conventions and Definitions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
3. Posture Assessment Scenarios
By way of example, the Center for Internet Security (CIS) hosts
recommended configuration settings to secure operating systems,
applications, and devices in CIS Benchmarks [BENCHMARKS] developed
with industry experts. Attestation Results aligned to the CIS
Benchmarks or other configuration guide such as one of the Defense
Information Systems Agency's Security Technical Implement Guides
[STIG] could be used to assert that the configuration meets
expectations. This has already been done for multiple platforms to
demonstrate assurance for firmware according to NIST SP 800-193,
Firmware Resiliency Guidelines [FIRMWARE]. In order to scale remote
attestation, a single set of Attestation Results for a set of
benchmarks or policies being met, with a link to the verification
logs from the local appraisals, is the Evidence that may be conveyed
to the Verifier and then the Relying Party. On traditional servers,
assurance to NIST SP 800-193 is provable through Evidence generated
from a Root of Trust (RoT), using the Trusted Computing Group (TCG)
Trusted Platform Module (TPM) chip and attestation formats. However,
this remains local and one knows the policies and measurements have
been met when other functions that rely on the assurance are running.
At boot, policy and measurement expectations are verified against a
set of Reference Values from collected Evidence and are verified to
meet expected values. Device identity and measurements can also be
attested at runtime, producing Evidence for appraisal. The
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generation of Evidence (e.g. hash of boot element) and appraisal of
Evidence are typically contained within a system and are limited to
the control plane for management. The policy and measurement sets
for comparison are protected to assure the result in the Evidence
appraisal process for boot elements. Event logs and PCR values may
be exposed to provide transparency into the appraised Evidence. The
Attestation Results defined in this document provide a summary of a
local appraisal of posture for managed systems and across various
layers (operating system, application, containers) in each of these
systems in a managed environment as Evidence. The Relying Party uses
the Attestation Results to understand posture of interconnected
operating systems, applications, and systems that are communicated in
summary Attestation Results.
There is a balance of exposure and evidence needed to assess posture
when providing assurance of controls and system state. Currently, if
using the TPM, logs and TPM PCR values may be passed to provide
assurance that appraised Evidence meets set requirements. Providing
the set of Evidence as assurance to a policy set can be accomplished
with a remote attestation format such as the Entity Attestation Token
(EAT) [I-D.ietf-rats-eat] aligned to the RATS Architecture [RFC9334]
and Attestation Results for Secure Interactions [I-D.ietf-rats-ar4si]
and a RESTful interface such as ROLIE [RFC8322] or RedFish [REDFISH].
Policy definition blocks may be scoped to control measurement sets,
where the EAT profile asserts compliance to the policy or measurement
block specified and may include claims with the log and PCR value
Evidence. Measurement and Policy sets, referenced in an EAT profile
may be published and maintained by separate entities (e.g. CIS
Benchmarks, DISA STIGs). The policy and measurement sets should be
maintained separately even if associated with the same benchmark or
control set. This avoids the need to transition the verifying entity
to a remote system for individual policy and measurements which are
performed locally for more immediate remediation as well as other
functions.
Examples of measurement and policy sets that could be defined in EAT
profiles include, but are not limited to:
* Hardware attribute certificates, TCG
* Hardware Attribute Certificate Comparison Results, TCG
* Reference Integrity Measurements for firmware, TCG
* Operating system benchmarks at Specified Assurance Levels, CIS
* Application hardening Benchmarks at Specified Assurance Levels,
CIS, DISA STIG
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* Container security benchmarks at Specified Assurance Levels, CIS
Scale, ease of use, full automation, and consistency for customer
consumption of a remote attestation function or service are essential
toward the goal of consistently securing systems against known
threats and vulnerabilities. Mitigations may be baked into policy.
Claim sets of measurements and policy verified to meet or not meet
Endorsed Values [I-D.ietf-rats-eat] are conveyed in an Entity
Attestation Token made available to a RESTful interface in aggregate
for the systems managed as Evidence for the Attestation Results. The
Measurement or Policy Set may be registered in the IANA registry
created in this document (Section 9), detailing the specific
configuration policies and measurements required to adhere or prove
compliance to the associated document to enable interoperability.
Levels (e.g. high, medium, low, 1, 2, 3) or vendor specific instances
of the policy defined in code required to verify the policy and
measurements would be registered using a name for the policy set,
that would also be used in the reporting EAT that includes the MPS
along with other artifacts to prove compliance.
4. Policy and Measurement Set Definitions
This document defines EAT claims in the JWT [RFC7519] and CWT
[RFC8392] registries to provide Attestation Results for a set of
verified claims within a defined grouping. The trustworthiness will
be conveyed on original appraised Evidence as well as the Attestation
Results on the grouping. The claims provide the additional
information needed for an EAT to convey compliance to a defined
policy or measurement set to a system or application collecting
evidence on policy and measurement assurance, for instance a
Governance, Risk, and Compliance (GRC) system.
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+=======+===========================+=====================+========+
| Claim | Long Name | Claim Description | Format |
+=======+===========================+=====================+========+
| mps | Measurement or Policy Set | Name for the MPS | |
+-------+---------------------------+---------------------+--------+
| lem | Log Evidence of MPS | Log File or URI | |
+-------+---------------------------+---------------------+--------+
| pcr | TPM PCR Values | URI | |
+-------+---------------------------+---------------------+--------+
| fma | Format of MPS Attestation | Format of included | |
| | Results | Attestation Results | |
+-------+---------------------------+---------------------+--------+
| hsh | Hash Value/Message Digest | Hash value of | |
| | | claim-set | |
+-------+---------------------------+---------------------+--------+
Table 1
5. Supportability and Re-Attestation
The remote attestation framework shall include provisions for a
Verifier Owner and Relying Party Owner to declare an Appraisal Policy
for Attestation Results and Evidence that allows for modification of
the Target Environment (e.g. a product, system, or service).
Over its lifecycle, the Target Environment may experience
modification due to: maintenance, failures, upgrades, expansion,
moves, etc..
The Relying Party Owner managing the Target Environment (e.g.
customer using the product) can choose to:
* Update the Appraisal Policy for Attestation Results and re-assess
posture with this updated policy, summarizing with a remote
attestation to the new policy or level, or
* Run remote attestation after modification of the Target
Environment as external validation, or
* Continue operation of the Target Environment as-is, without
verification, potentially increasing risk
In the case of Re-Attestation:
* framework needs to invalidate previous Reference Values (e.g. TPM
PCR values and tokens),
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* framework needs to specify an Appraisal Policy for Evidence that
requires fresh Evidence,
* framework needs to maintain history or allow for history to be
logged to enable change traceability attestation, and
* framework needs to notify that the previous Attestation Results
has been invalidated
6. Configuration Sets
In some cases, it may be difficult to attest to configuration
settings for the initial or subsequent attestation and verification
processes. The use of an expected hash value for configuration
settings can be used to compare against the attested configuration
set. In this case, the creator of the Evidence appraisal
measurements would define a set of values for which a message digest
would be created and then signed by the Attester. The expected
measurements would include the expected hash value for comparison.
The configuration set could be the full attestation set to a
Benchmark or a defined subset. These configuration sets can be
registered for general use to reduce the need to replicate the policy
and measurement assessments by others aiming to assure at the same
level for a benchmark or hardening guide.
This document creates an IANA registry for this purpose, creating
consistency between automated policy and measurement set levels and
the systems used to collect and report aggregate views for an
organization across systems and applications, such as a GRC platform.
7. Remediation
If policy and configuration settings or measurements attested do not
meet expected values, remediation is desirable. Automated
remediation performed with alignment to zero trust architecture
principles would require that the remediation be performed prior to
any relying component executing. The relying component would verify
before continuing in a zero trust architecture.
Ideally, remediation would occur on-system as part of the process to
generate Evidence for a set of claims, similar to how Evidence is
generated for firmware in the boot process. If automated remediation
is not possible, an alert should be generated to allow for
notification of the variance from expected values.
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8. Security Considerations
This document establishes a pattern to list sets of benchmarks and
controls within CWT and JWT formats. The contents of the benchmarks
and controls are out of scope for this document. This establishes an
architectural pattern whereby Attestation Results could be produced
for a complete set of benchmarks or controls as defined and grouped
by external entities, preventing the need to convey individual
Evidence items for each item within a benchmark or control framework.
This document does not add security consideration over what has been
described in the EAT, JWT, or CWT specifications.
9. IANA Considerations
9.1. Reuse of CBOR and JSON Web Token (CWT and JWT) Claims Registries
Claims defined in this document are a profile of EAT. Like the base
claims of EAT, the claims below are compatible with those of CWT and
JWT so the CWT and JWT Claims Registries, [IANA.CWT.Claims] and
[IANA.JWT.Claims], are re-used. No new IANA registry is created.
All EAT claims defined in this document are placed in both
registries.
9.2. CWT and JWT Claims Registered by This Document
This document requests the creation of a Measurement and Policy Set
(MPS) registry. The MPS registry will contain the names of the
Benchmarks, Policy sets, DISA STIGS, controls, or other groupings as
a policy and measurement set that MAY correlate to standards
documents containing assurance guidelines, compliance requirements,
or other defined claim sets for verification of posture assessment to
that MPS. The MPS registry will include the policy definition for
specific levels of MPS assurance to enable interoperability between
Attestation Results asserting compliance (or lack thereof) and
reporting systems.
+===============+=======================+==========================+
| MPS Name | MPS Description | File with MPS definition |
+===============+=======================+==========================+
| Ubuntu-CIS-L1 | Ubuntu CIS Benchmark, | http:// /Ubuntu-CIS- |
| | level 1 assurance | L1.txt |
+---------------+-----------------------+--------------------------+
Table 2
The MPS name includes versions or level information, allowing for
distinct policy or measurement sets and definitions of those sets
(including the supporting formats used to write the definitions).
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9.3. Additions to the JWT and CWT registries requested
This document requests the following JWT claims per the specification
requirement required for the JSON Web Token (JWT) registry defined in
RFC7519.
+=======+===================================+=====================+
| Claim | Long Name | Claim Description |
+=======+===================================+=====================+
| MPS | Measurement or Policy Set | Name for the MPS |
+-------+-----------------------------------+---------------------+
| LEM | Log Evidence of MPS | Log File or URI |
+-------+-----------------------------------+---------------------+
| PCR | TPM PCR Values | URI |
+-------+-----------------------------------+---------------------+
| FMA | Format of MPS Attestation Results | Format of included |
| | | Attestation Results |
+-------+-----------------------------------+---------------------+
| HSH | Hash Value/Message Digest | Hash value of |
| | | claim-set |
+-------+-----------------------------------+---------------------+
Table 3
9.4. MPS (Measurement or Policy Set) Claim
The MPS (Measurement or Policy Set) claim identifies the policy and
measurement set being reported. The MPS MAY be registered to the MPS
IANA registry. The MPS may be specified to specific levels of
assurance to hardening, loosening guides or benchmarks to provide
interoperability in reporting. The processing of this claim is
generally application specific. The MPS value is a case-sensitive
string containing a StringOrURI value. Use of this claim is
OPTIONAL.
This document requests the following CWT claims per the specification
requirement required for the CBOR Web Token (CWT) registry defined in
RFC8392.
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+=======+=====================+=====================+===========+
| Claim | Long Name | Claim Description | JWT Claim |
| | | | Name |
+=======+=====================+=====================+===========+
| MPS | Measurement or | Name for the MPS | MPS |
| | Policy Set | | |
+-------+---------------------+---------------------+-----------+
| LEM | Log Evidence of MPS | Log File or URI | LEM |
+-------+---------------------+---------------------+-----------+
| PCR | TPM PCR Values | URI | PCR |
+-------+---------------------+---------------------+-----------+
| FMA | Format of MPS | Format of included | FMA |
| | Attestation Results | Attestation Results | |
+-------+---------------------+---------------------+-----------+
| HSH | Hash Value/Message | Hash value of | HSH |
| | Digest | claim-set | |
+-------+---------------------+---------------------+-----------+
Table 4
10. Appendix A – Extended Claims Table with RoT Variants
10.1. A.1 – Chained Attestation and Measurement Exposure Across
Hardware Roots of Trust
+=========+===========+=============+===============+==============+
|Platform |Hardware | Measurement | Attestation | PCR/ |
| |Root of | Chaining | Evidence | Measurement |
| |Trust | | | Exposure |
+=========+===========+=============+===============+==============+
|DICE |Minimal | Yes | Stage | CDIs (not |
| |hardware + | | certificates, | standard |
| |UDS | | attestation | PCRs) |
| | | | chain | |
+---------+-----------+-------------+---------------+--------------+
|Apple |Boot ROM & | Yes | Internal | Not standard |
| |Secure | | logs, | PCRs |
| |Enclave | | biometric/ | (internal |
| | | | auth evidence | use) |
+---------+-----------+-------------+---------------+--------------+
|OpenTitan|Open-source| Yes | Logs, | TPM-like |
| |silicon | | certificates | PCRs |
| |chip | | | |
+---------+-----------+-------------+---------------+--------------+
|Amazon |Nitro | Yes | NitroTPM | NitroTPM |
|Nitro |Security | | logs, AWS- | PCRs |
| |Chip | | signed | |
| | | | attestation | |
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+---------+-----------+-------------+---------------+--------------+
|Nitro |Nitro | Yes | AWS-signed | Enclave PCRs |
|Enclaves |Security | | attestation | |
| |Chip + | | tokens | |
| |Hypervisor | | | |
+---------+-----------+-------------+---------------+--------------+
Table 5
10.2. A.2 – Extended Claims Table with DICE, Apple Secure Enclave,
OpenTitan, and Amazon Nitro
+=========+=====+===========+=====================+=================+
|Platform |Claim|Long Name | Claim Description |Format |
| | | | (with RoT | |
| | | | Mechanism) | |
+=========+=====+===========+=====================+=================+
|DICE |mps |Measurement| DICE CDI lineage: |CDI derivation |
| | |or Policy | Minimalist |chain; |
| | |Set | hardware root of |certificate-based|
| | | | trust (UDS in ROM/ |attestation |
| | | | SoC), performs | |
| | | | measured boot, | |
| | | | derives Compound | |
| | | | Device Identifiers | |
| | | | (CDIs) at each | |
| | | | boot stage, | |
| | | | binding device and | |
| | | | firmware state. | |
+---------+-----+-----------+---------------------+-----------------+
|DICE |lem |Log | Implementation- |Log file, |
| | |Evidence of| specific logs and |attestation |
| | |MPS | attestation |certificate, or |
| | | | certificates; |URI |
| | | | evidence is the | |
| | | | chain of CDIs and | |
| | | | alias | |
| | | | certificates, | |
| | | | often used in TLS | |
| | | | client | |
| | | | authentication. | |
+---------+-----+-----------+---------------------+-----------------+
|DICE |pcr |TPM PCR | Not applicable; |— |
| | |Values | DICE does not use | |
| | | | TPM PCRs. | |
| | | | Instead, it uses | |
| | | | derived | |
| | | | cryptographic | |
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| | | | identities (CDIs) | |
| | | | per boot stage. | |
+---------+-----+-----------+---------------------+-----------------+
|Apple |mps |Measurement| Secure Enclave |Local attestation|
| | |or Policy | root identity and |(UID + monotonic |
| | |Set | enclave |counter); enclave|
| | | | measurements: |measurement logs |
| | | | Hardware root of | |
| | | | trust (immutable | |
| | | | Boot ROM in SoC), | |
| | | | secure boot of SEP | |
| | | | OS, device-unique | |
| | | | UID, monotonic | |
| | | | counter for anti- | |
| | | | replay/rollback, | |
| | | | local attestation. | |
+---------+-----+-----------+---------------------+-----------------+
|Apple |lem |Log | SEP logs, anti- |Internal log file|
| | |Evidence of| replay/rollback |or counter |
| | |MPS | counters, internal | |
| | | | secure boot logs | |
| | | | (not externally | |
| | | | exposed); used for | |
| | | | local security and | |
| | | | policy | |
| | | | enforcement. | |
+---------+-----+-----------+---------------------+-----------------+
|Apple |pcr |TPM PCR | Not applicable; |— |
| | |Values | Apple does not | |
| | | | expose TPM PCRs. | |
| | | | Integrity is | |
| | | | enforced using | |
| | | | UID, monotonic | |
| | | | counters, and | |
| | | | secure boot chain. | |
+---------+-----+-----------+---------------------+-----------------+
|OpenTitan|mps |Measurement| Boot-time firmware |Hardware-backed |
| | |or Policy | validation and |attestation logs |
| | |Set | Creator Identity |and certificates |
| | | | checks: Open- | |
| | | | source silicon | |
| | | | root of trust | |
| | | | (boot ROM in | |
| | | | silicon), measured | |
| | | | boot, stable | |
| | | | Creator Identity, | |
| | | | hardware-backed | |
| | | | key management, | |
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| | | | remote | |
| | | | attestation. | |
+---------+-----+-----------+---------------------+-----------------+
|OpenTitan|lem |Log | Firmware integrity |Certificate-based|
| | |Evidence of| logs, certificate- |attestation, log |
| | |MPS | based attestation, |file |
| | | | logs tied to | |
| | | | Creator Identity | |
| | | | and measured boot | |
| | | | state. | |
+---------+-----+-----------+---------------------+-----------------+
|OpenTitan|pcr |TPM PCR | Custom attestation |Hardware-backed |
| | |Values | logs; supports |boot state, TPM- |
| | | | TPM-like PCRs for |like PCRs |
| | | | remote | |
| | | | attestation, but | |
| | | | uses a stable | |
| | | | Creator Identity | |
| | | | rather than | |
| | | | evolving device | |
| | | | identity at each | |
| | | | firmware layer. | |
+---------+-----+-----------+---------------------+-----------------+
|Amazon |mps |Measurement| Secure boot and |NitroTPM PCR |
|Nitro | |or Policy | firmware |values, AWS- |
| | |Set | validation: Nitro |signed |
| | | | Security Chip as |attestation |
| | | | hardware root of | |
| | | | trust, NitroTPM | |
| | | | provides virtual | |
| | | | TPM instance with | |
| | | | PCRs, measured | |
| | | | boot, and remote | |
| | | | attestation for | |
| | | | cloud servers and | |
| | | | Nitro Enclaves. | |
+---------+-----+-----------+---------------------+-----------------+
|Amazon |lem |Log | NitroTPM logs, |AWS-signed |
|Nitro | |Evidence of| attestation |attestation, |
| | |MPS | evidence, logs |NitroTPM log file|
| | | | signed by AWS; | |
| | | | used for remote | |
| | | | attestation and | |
| | | | verification of | |
| | | | cloud instance or | |
| | | | enclave state. | |
+---------+-----+-----------+---------------------+-----------------+
|Amazon |pcr |TPM PCR | NitroTPM PCR |Cryptographically|
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|Nitro | |Values | values |signed PCR |
| | | | (cryptographically |values, standard |
| | | | signed, used for |TPM 2.0 format |
| | | | attestation and | |
| | | | sealing secrets to | |
| | | | boot state); | |
| | | | standard TPM 2.0 | |
| | | | interface for EC2 | |
| | | | instances and | |
| | | | Nitro Enclaves. | |
+---------+-----+-----------+---------------------+-----------------+
Table 6
11. References
11.1. Normative References
[I-D.ietf-rats-ar4si]
Fossati, T., Voit, E., and S. Trofimov, "Attestation
Results for Secure Interactions", Work in Progress,
Internet-Draft, draft-ietf-rats-ar4si-07, March 2025,
<https://datatracker.ietf.org/doc/html/draft-ietf-rats-
ar4si-07>.
[I-D.ietf-rats-eat]
Lundblade, L., Mandyam, G., O'Donoghue, J., and C.
Wallace, "The Entity Attestation Token (EAT)", Work in
Progress, Internet-Draft, draft-ietf-rats-eat-31, 6
September 2024, <https://datatracker.ietf.org/doc/html/
draft-ietf-rats-eat-31>.
[IANA.CWT.Claims]
IANA, "CBOR Web Token (CWT) Claims",
<https://www.iana.org/assignments/cwt>.
[IANA.JWT.Claims]
IANA, "JSON Web Token (JWT)",
<https://www.iana.org/assignments/jwt>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/rfc/rfc2119>.
[RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
(JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015,
<https://www.rfc-editor.org/rfc/rfc7519>.
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[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.
[RFC8392] Jones, M., Wahlstroem, E., Erdtman, S., and H. Tschofenig,
"CBOR Web Token (CWT)", RFC 8392, DOI 10.17487/RFC8392,
May 2018, <https://www.rfc-editor.org/rfc/rfc8392>.
[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/rfc/rfc9334>.
11.2. Informative References
[BENCHMARKS]
"Center for Internet Security Benchmarks List", n.d.,
<https://www.cisecurity.org/cis-benchmarks>.
[FIRMWARE] Regenscheid, A., "Platform firmware resiliency
guidelines", National Institute of Standards and
Technology, DOI 10.6028/nist.sp.800-193, May 2018,
<https://doi.org/10.6028/nist.sp.800-193>.
[REDFISH] "Redfish Specification Version 1.20.0", n.d.,
<https://www.dmtf.org/sites/default/files/standards/
documents/DSP0266_1.20.0.pdf>.
[RFC8322] Field, J., Banghart, S., and D. Waltermire, "Resource-
Oriented Lightweight Information Exchange (ROLIE)",
RFC 8322, DOI 10.17487/RFC8322, February 2018,
<https://www.rfc-editor.org/rfc/rfc8322>.
[STIG] "Defense Information Systems Agency Security Technical
Implementation Guides", n.d.,
<https://public.cyber.mil/stigs/>.
Contributors
Thank you to reviewers and contributors who helped to improve this
document. Thank you to Nick Grobelney, Dell Technologies, for your
review and contribution to separate out the policy and measurement
sets. Thank you, Samant Kakarla and Huijun Xie from Dell
Technologies, for your detailed review and corrections on boot
process details. Section 3 has been contributed by Rudy Bauer from
Dell as well and an author will be added on the next revision. IANA
section added in version 7 by Kathleen Moriarty, expanding the claims
registered and adding a proposed registry to define policy and
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measurement sets. Thank you to Henk Birkholz for his review and
edits. Thanks to Thomas Fossati, Michael Richardson, and Eric Voit
for their detailed reviews on the mailing list. Thank you to A.J.
Stein for converting the XMLMind workflow to Markdown and GitHub,
editorial contributions, and restructuring of the document.
Authors' Addresses
Kathleen M. Moriarty
Transforming Information Security LLC
MA
United States of America
Email: kathleen.Moriarty.ietf@gmail.com
Monty Wiseman
Beyond Identity
3 Park Avenue
NY, NY 10016
United States of America
Email: monty.wiseman@beyondidentity.com
A.J. Stein
United States of America
Email: ajstein.standards@gmail.com
URI: https://orcid.org/0000-0003-1092-2642
Chandra Nelogal
Dell Technologies
176 South Street
MA 01748
United States of America
Email: chandra.nelogal@dell.com
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