<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE rfc [
  <!ENTITY nbsp    "&#160;">
  <!ENTITY zwsp   "&#8203;">
  <!ENTITY nbhy   "&#8209;">
  <!ENTITY wj     "&#8288;">
]>
<?xml-stylesheet type="text/xsl" href="rfc2629.xslt" ?>
<!-- generated by https://github.com/cabo/kramdown-rfc version 1.7.17 (Ruby 3.0.2) -->
<rfc xmlns:xi="http://www.w3.org/2001/XInclude" ipr="trust200902" docName="draft-liu-nasr-architecture-00" category="info" submissionType="IETF" xml:lang="en" version="3">
  <!-- xml2rfc v2v3 conversion 3.22.0 -->
  <front>
    <title abbrev="NASR-Architecture">Network Attestation for Secure Routing (NASR) Architecture</title>
    <seriesInfo name="Internet-Draft" value="draft-liu-nasr-architecture-00"/>
    <author fullname="Chunchi Liu">
      <organization>Huawei</organization>
      <address>
        <email>liuchunchi@huawei.com</email>
      </address>
    </author>
    <author fullname="Meiling Chen">
      <organization>China Mobile</organization>
      <address>
        <email>chenmeiling@chinamobile.com</email>
      </address>
    </author>
    <author fullname="Michael Richardson">
      <organization>Sandelman Software Works</organization>
      <address>
        <email>mcr@sandelman.ca</email>
      </address>
    </author>
    <author fullname="Diego Lopez">
      <organization>Telefonica</organization>
      <address>
        <email>diego.r.lopez@telefonica.com</email>
      </address>
    </author>
    <date year="2024" month="July" day="07"/>
    <area>SEC</area>
    <workgroup>NASR</workgroup>
    <keyword>NASR</keyword>
    <keyword>Secure Routing</keyword>
    <abstract>
      <?line 49?>

<t>This document provides an architecture overview of NASR entities, interactive procedures and messages.</t>
    </abstract>
  </front>
  <middle>
    <?line 53?>

<section anchor="introduction">
      <name>Introduction</name>
      <t>Endpoints typically perceives no information of the properties of the paths over which their traffic is carried, especially when the properties are security-related. Therefore, data security (confidentiality, integrity and authenticity) has been insofar primarily protected by traffic signing and encryption mechanisms. Endpoint cannot choose devices with specific properties to bear transmission.</t>
      <t>However, clients with high security and privacy requirements are not anymore satisfied with traffic signing and encryption mechanisms only; they now request information of the trustworthiness or security properties of the network paths over which the traffic is carried, preferably to choose the desired properties. For example, some clients may require their data to traverse through trusted devices and trusted links only, in order to avoid data being exposed to insecure devices, causing leakage.</t>
      <t>Remote Attestation Procedures (RATS) working group developed procedures to establish a level of confidence in the trustworthiness of a device or a system. RATS provide 1. objective, appraisable evidence of a device’s trust or security properties, and 2. verifiable integrity proof to the evidence (Attestation Result). Devices with integrity proof are expected to function correctly and deterministically, as anticipated.</t>
      <t>Following the same RATS philosophy and building on top of it, Network Attestation for Secure Routing （NASR) aims at a solution specifically designed for the routing use case. NASR aims to provide 1. objective, appraisable evidence of a routing path’s trust or security properties, 2. verifiable integrity proof in the path-level, and 3. verifiable proof that certain packets/flows traveled such paths.</t>
      <t>Altogether, the NASR goal is to 1. Allow clients to choose desired security attributes of his received network service, 2. Achieve dependable forwarding by routing on top of only devices that satisfies certain trust requirements, and 3. prove to the clients that certain packets or flows traversed a network path that has certain trust or security properties.</t>
      <t>This document introduces the architecture, entities, interactive procedures, and messages sent between the entities, so to achieve the NASR objective.</t>
    </section>
    <section anchor="usecases">
      <name>Use Cases</name>
      <t>Please refer to the use cases identified in <xref target="I-D.liu-nasr-requirements-01"/></t>
    </section>
    <section anchor="term">
      <name>Terminology</name>
      <t>Please refer to the terminologies identified in <xref target="I-D.richardson-nasr-terminology-01"/>. Terminology from RATS Architecture document <xref target="RFC9344"/> also applies.</t>
      <t>NASR will leverage RATS implementations and specifications, including but not limited to <xref target="I-D.ietf-rats-ar4si-06"/><xref target="I-D.ietf-rats-corim-04"/>.</t>
    </section>
    <section anchor="architectural-overview">
      <name>Architectural Overview</name>
      <section anchor="single-client-single-operator-an-oversimplification">
        <name>Single client - single operator (An Oversimplification)</name>
        <artwork><![CDATA[
+--------------------+
|                    |
|    Relying Party   |
|                    |
|                    |
+----+---------^-----+   Path   |         |   Request|         | Report
     |         |
+----v---------+-----+                                    +--------------------+
|                    |     Path Attestation Result (PAR)  |                    |
|    Orchestrator    |                                    |      Verifier      |
|                    <------------------------------------+                    |
|                    |                                    |                    |
+----+---------------+                                    +----------^---------+
     |                                                               | Path     |                                                               |  Path Evidence |                                                               |  Evidence (PE)     |                                                               |  (PE)
+----v---------------+       +--------------------+       +----------+---------+
|                    |       |                    |       |                    |
|      Attester      +------->     Attester...    +------->      Attester      |
|                    |       |                    |       |                    |
+--------------------+       +--------------------+       +--------------------+
                  Update PE with                Update PE with
                    AR/RE/PoT                     AR/RE/PoT
]]></artwork>
        <t>Figure 1. NASR Architecture-- Oversimplified</t>
        <t>Fig. 1 is an oversimplification to ease understanding of the concept. In a single client - single operator scenario, a client (Relying Party) sends a Path Request containing his security or trustworthiness requirements of a leased line. The Orchestrator, run by the operator, would choose qualifying devices (Attesters) and send out an empty Path Evidence inquiry. The Attesters update the Path Evidence with its own Raw Evidence or Attestation Results one-by-one. The Verifier verifies the filled Path Evidence, produce a Path Attestation Result (PAR), and sends it back to the Relying Party. The Relying Party now have confidence over the trustworthiness of received network. After the end-to-end service is delivered, during service, Proof-of-Transits are also created by each Attester, being sent in-band accumulatively or out-of-band, to detect unexpected routing deviation.</t>
        <t>This process is repeated periodically to continuously assure compliance.</t>
      </section>
      <section anchor="multi-client-multi-operator">
        <name>Multi Client - Multi Operator</name>
        <artwork><![CDATA[
                           ┌────────────────────────────────────────────────────────────────┐
                           │                                                                │
                           │       ┌────────────┐                 ┌────────────┐            │
                           │       │ Verifier   │                 │ Verifier   │    ...     │
                           │       │ Vendor A   │                 │ Vendor B   │            │
 ┌───────────────────┐     │       └────▲─────┬─┘                 └───▲────┬───┘   Vendors  │    ┌───────────────────┐
 │                   │     │            │     │                       │    │                │    │                   │
 │                   │     └────────────┼─────┼───────────────────────┼────┼────────────────┘    │                   │
 │    Client  A      │                  │     │                       │    │                     │    Client  B      │
 │                   │  Path            │     │                       │    │         Path        │                   │
 │  ┌──────────────┐ │  Request         │     │                       │    │         Attestation │   ┌────────────┐  │
 │  │  Relying     ├─┼──────────┐ ┌─────┼─────┼───────┐        ┌──────┼────┼───────┐ Result (PAR)│   │  Relying   │  │
 │  │  Party       │ │          │ │     │     │       │        │      │    │       │     ┌───────┼───┤  Party     │  │
 │  └───┬──────────┘◄├────────┐ │ │     │     │       │  Intra │      │    │       │     │       │   └────────────┘  │
 │      │            │        │ │ │  RE │     │AR     │  ISP   │   RE │    │ AR    │     │       │           ▲       │
 │      │            │ Answer │ └─► ┌───┴─────▼─────┐ │  API   │  ┌───┴────▼────┐  │     │       │           │       │
 │      │Path        │ Report │   │ │ Orchestrator  ├─┼────────┼─►│ Orchestrator│◄─┼─────┘       │           │       │
 │      │Evidence    │        └───┤ └───▲─────┬─────┘ │        │  └───▲────┬────┘  │             │           │       │
 │      │            │            │     │     │       │        │      │    │       │             │           │       │
 │      │            │            │  RE │     │AR     │        │   RE │    │ AR    │             │           │       │
 │   ┌──▼────────┐   │            │ ┌───┴─────▼─────┐ │        │  ┌───┴────▼─────┐ │             │   ┌───────┴───┐   │
 │   │ Attester  │   │            │ │  Attester     │ │        │  │  Attester    │ │             │   │ Attester  │   │
 │   │           ├───┼────────────┤►│  Vendor A     ├─┼────────┼─►│  Vendor B    ├─┼─────────────┼──►│           │   │
 │   └───────────┘   │  Update PE │ └───────────────┘ │        │  └──────────────┘ │  Update PE  │   └───────────┘   │
 │                   │    with    │                   │        │                   │    with     │                   │
 │                   │  AR/RE/PoT │  Operator 1       │        │   Operator 2      │  AR/RE/PoT  │                   │
 └───────────────────┘            └───────────────────┘        └───────────────────┘             └───────────────────┘

Figure 2. NASR Architecture

In a more generalized scenario, due to geographic distances, a single operator cannot span across a long distance to deliver an end-to-end service-- multiple operators collaborate to deliver it. The Customer A would send the Path Request to the Operator nearest to him (Operator 1). Operator 1 pass down the Path Request to the collaborating operators, through an intra-ISP API. Operators of different domains choose qualifying devices to altogether orchestrate the path.

Relying Party (customer) then sends the Path Evidence inquiry to check and attest to this path. Following the same procedure, the client of other side would return the Path Attestation Result back, through the operators. The Operator 1 would send back a comprehensive answer/report to the Client.

Also, the operators may have heterogeneous network devices from different vendors. Since vendors provide Verifier software/hardware and Reference Values, Verifiers can be deployed either outside the operators (Fig 2) or inside of the operators (Fig 3).

                           ┌────────────────────────────────────────────────────────────────┐
                           │                                                                │
                           │       ┌────────────┐                 ┌────────────┐            │
                           │       │ Verifier   │                 │ Verifier   │            │
                           │       │ Owner      │                 │ Owner      │    ...     │
                           │       │ Vendor A   │                 │ Vendor B   │            │
                           │       └───────┬────┘                 └──────┬─────┘   Vendors  │
                           │               │                             │                  │
                           └───────────────┼─────────────────────────────┼──────────────────┘
                                           │  Verifier software/hardware │
                                           │  Reference Value            │
 ┌───────────────────┐            ┌────────┼──────────┐        ┌─────────┼─────────┐             ┌───────────────────┐
 │                   │            │        │          │        │         │         │             │                   │
 │                   │            │  ┌─────▼──────┐   │        │   ┌─────▼──────┐  │             │                   │
 │    Client  A      │            │  │ Verifier   │   │        │   │ Verifier   │  │             │    Client  B      │
 │                   │  Path      │  │ from       │   │        │   │ from       │  │ Path        │                   │
 │  ┌──────────────┐ │  Request   │  │ Vendor A   │   │        │   │ Vendor B   │  │ Attestation │   ┌────────────┐  │
 │  │  Relying     ├─┼──────────┐ │  └──┬─────┬───┘   │        │   └──┬────┬────┘  │ Result (PAR)│   │  Relying   │  │
 │  │  Party       │ │          │ │     │     │       │        │      │    │       │     ┌───────┼───┤  Party     │  │
 │  └───┬──────────┘◄├────────┐ │ │     │     │       │  Intra │      │    │       │     │       │   └────────────┘  │
 │      │            │        │ │ │  RE │     │AR     │  ISP   │   RE │    │ AR    │     │       │           ▲       │
 │      │            │        │ └─► ┌───┴─────▼─────┐ │  API   │  ┌───┴────▼────┐  │     │       │           │       │
 │      │Path        │ Report │   │ │ Orchestrator  ├─┼────────┼─►│ Orchestrator│◄─┼─────┘       │           │       │
 │      │Evidence    │        └───┤ └───▲─────┬─────┘ │        │  └───▲────┬────┘  │             │           │       │
 │      │            │            │     │     │       │        │      │    │       │             │           │       │
 │      │            │            │  RE │     │AR     │        │   RE │    │ AR    │             │           │       │
 │   ┌──▼────────┐   │            │ ┌───┴─────▼─────┐ │        │  ┌───┴────▼─────┐ │             │   ┌───────┴───┐   │
 │   │ Attester  │   │            │ │  Attester     │ │        │  │  Attester    │ │             │   │ Attester  │   │
 │   │           ├───┼────────────┼─┤  Vendor A     ├─┼────────┼─►│  Vendor B    ├─┼─────────────┼──►│           │   │
 │   └───────────┘   │  Update PE │ └───────────────┘ │        │  └──────────────┘ │  Update PE  │   └───────────┘   │
 │                   │    with    │                   │        │                   │    with     │                   │
 │                   │  AR/RE/PoT │  Operator 1       │        │   Operator 2      │  AR/RE/PoT  │                   │
 └───────────────────┘            └───────────────────┘        └───────────────────┘             └───────────────────┘


Figure 3. Verifier deployed in operators

# Roles {#roles}

The existing roles from RATS Architecture document {{RFC9344}} applies.

- Attester: The definition in {{RFC9344}} applies. Additionally, it can be performed by either a physical device or a virtual function. The Attester can update Path Evidence with his Attestation Result/Raw Evidence/Proof of Transit.

    - Produces: (updated) Path Evidence

- Relying Party: The definition in {{RFC9344}} applies. Additionally, it creates Path Request to the Orchestrator, and receive Reports from Orchestrator as an auditable result, comparing the actually received network service versus the requested PR attributes.

    - Produces: Path Request

    - Consumes: Report

In the case where an Attester is deployed in the customer premises, the Relying Party could also start the unfilled Path Evidence inquiry at his side.

New role(s) are defined below.

- Orchestrator: A role performed by an entity (typically a controller or a special device) that performs two functions: path orchestration and path attestation. The input and output of different functions are different.

  - Path Orchestration: The Orchestrator receives a Path Request from the Relying Party. After path computation/orchestration, he creates configurations to be distributed to the Attesters/devices.

    - Consumes: Path Request

    - Produces: Configurations

  - Path Attestation: The Orchestrator receives a Path Request from the Relying Party, send unfilled Path Evidence (PE) inquiry to Attesters, collects Path Attestation Result (PAR) from the Verifier, and send PAR back to the Relying Party.

    - Consumes: Path Request, Path Attestation Result

    - Produces: (unfilled) Path Evidence

- Verifier: A role performed by an entity that appraises the validity of filled Path Evidence about a set of Attesters and produces Path Attestation Results to be used by an Orchestrator.

    - Consumes: (filled) Path Evidence

    - Produces: Path Attestation Results

# Conceptual Messages {#messages}

The existing artifacts from RATS Architecture document {{RFC9344}} applies. New conceptual message(s) are defined here.

- Path Request: A set of claims, describing the properties of a network path that a Relying Party requested.

    - Consumed By: Orchestrator

    - Produced By: Relying Party

- Path Attestation Result: The output generated by a Verifier, including information about a set of Attesters, where the Verifier vouches for the validity of the results.

    - Consumed By: Relying Party

    - Produced By: Verifier

- Path Evidence: The output generated by the Orchestrator and a set of Attesters, to be appraised by a Verifier. Path Evidence may include each Attester's raw Evidence {{RFC9344}}, Attestation Results, Proof-of-Transit, or other proof suggesting correctness of functioning of each Attester.

    - Consumed By: Verifier

    - Created By: Orchestrator

    - Updated By: Attester(s)

- Report: An auditable result that compares the actually received network service versus the requested PR attributes.

    - Created By: Orchestrator

    - Consumed By: Relying Party

# Orchestration

The orchestration process collects client's path requests and output configurations. The Orchestrator/Controller then distribute them to the attester/device using NETCONF/YANG or other control plane protocols. In the first case, a new YANG module needs to be defined.

]]></artwork>
        <artwork><![CDATA[
           +------------------------+
           |                        | Path Request   |Orchestrator/Controller | -------------->|                        |
           +----------+-------------+
                      |
                      |Path and Security Configuration
                      |(YANG/NETCONF)
                      |
                +-----v------------+
                | Attester/Device  |
                +------------------+
]]></artwork>
        <t>~~~~</t>
      </section>
    </section>
    <section anchor="security-considerations">
      <name>Security Considerations</name>
      <t>TODO Security</t>
    </section>
    <section anchor="iana-considerations">
      <name>IANA Considerations</name>
      <t>This document has no IANA actions.</t>
    </section>
  </middle>
  <back>
    <references anchor="sec-informative-references">
      <name>Informative References</name>
      <reference anchor="RFC9344">
        <front>
          <title>CCNinfo: Discovering Content and Network Information in Content-Centric Networks</title>
          <author fullname="H. Asaeda" initials="H." surname="Asaeda"/>
          <author fullname="A. Ooka" initials="A." surname="Ooka"/>
          <author fullname="X. Shao" initials="X." surname="Shao"/>
          <date month="February" year="2023"/>
          <abstract>
            <t>This document describes a mechanism named "CCNinfo" that discovers information about the network topology and in-network cache in Content-Centric Networks (CCNs). CCNinfo investigates 1) the CCN routing path information per name prefix, 2) the Round-Trip Time (RTT) between the content forwarder and the consumer, and 3) the states of in-network cache per name prefix. CCNinfo is useful to understand and debug the behavior of testbed networks and other experimental deployments of CCN systems.</t>
            <t>This document is a product of the IRTF Information-Centric Networking Research Group (ICNRG). This document represents the consensus view of ICNRG and has been reviewed extensively by several members of the ICN community and the RG. The authors and RG chairs approve of the contents. The document is sponsored under the IRTF, is not issued by the IETF, and is not an IETF standard. This is an experimental protocol and the specification may change in the future.</t>
          </abstract>
        </front>
        <seriesInfo name="RFC" value="9344"/>
        <seriesInfo name="DOI" value="10.17487/RFC9344"/>
      </reference>
      <reference anchor="I-D.liu-nasr-requirements-01">
        <front>
          <title>NASR Use Case and Requirements</title>
          <author fullname="Peter Chunchi Liu" initials="P. C." surname="Liu">
            <organization>Huawei</organization>
          </author>
          <author fullname="Luigi Iannone" initials="L." surname="Iannone">
            <organization>Huawei</organization>
          </author>
          <author fullname="Diego Lopez" initials="D." surname="Lopez">
            <organization>Telefonica</organization>
          </author>
          <author fullname="Antonio Pastor" initials="A." surname="Pastor">
            <organization>Telefonica</organization>
          </author>
          <author fullname="Meiling Chen" initials="M." surname="Chen">
            <organization>China Mobile</organization>
          </author>
          <author fullname="Li Su" initials="L." surname="Su">
            <organization>China Mobile</organization>
          </author>
          <date day="3" month="March" year="2024"/>
          <abstract>
            <t>   This document describes the use cases and requirements that guide the
   specification of a Network Attestation for Secure Routing framework
   (NASR).

            </t>
          </abstract>
        </front>
        <seriesInfo name="Internet-Draft" value="draft-liu-nasr-requirements-01"/>
      </reference>
      <reference anchor="I-D.richardson-nasr-terminology-01">
        <front>
          <title>Terminology and Use cases for Secured Routing Infrastructure</title>
          <author fullname="Michael Richardson" initials="M." surname="Richardson">
            <organization>Sandelman Software Works</organization>
          </author>
          <author fullname="Peter Chunchi Liu" initials="P. C." surname="Liu">
            <organization>Huawei Technologies</organization>
          </author>
          <date day="20" month="May" year="2024"/>
          <abstract>
            <t>   This document collects terminology and use cases for Secured Routing.

            </t>
          </abstract>
        </front>
        <seriesInfo name="Internet-Draft" value="draft-richardson-nasr-terminology-01"/>
      </reference>
      <reference anchor="I-D.ietf-rats-ar4si-06">
        <front>
          <title>Attestation Results for Secure Interactions</title>
          <author fullname="Eric Voit" initials="E." surname="Voit">
            <organization>Cisco Systems</organization>
          </author>
          <author fullname="Henk Birkholz" initials="H." surname="Birkholz">
            <organization>Fraunhofer SIT</organization>
          </author>
          <author fullname="Thomas Hardjono" initials="T." surname="Hardjono">
            <organization>MIT</organization>
          </author>
          <author fullname="Thomas Fossati" initials="T." surname="Fossati">
            <organization>Linaro</organization>
          </author>
          <author fullname="Vincent Scarlata" initials="V." surname="Scarlata">
            <organization>Intel</organization>
          </author>
          <date day="4" month="March" year="2024"/>
          <abstract>
            <t>   This document defines reusable Attestation Result information
   elements.  When these elements are offered to Relying Parties as
   Evidence, different aspects of Attester trustworthiness can be
   evaluated.  Additionally, where the Relying Party is interfacing with
   a heterogeneous mix of Attesting Environment and Verifier types,
   consistent policies can be applied to subsequent information exchange
   between each Attester and the Relying Party.

            </t>
          </abstract>
        </front>
        <seriesInfo name="Internet-Draft" value="draft-ietf-rats-ar4si-06"/>
      </reference>
      <reference anchor="I-D.ietf-rats-corim-04">
        <front>
          <title>Concise Reference Integrity Manifest</title>
          <author fullname="Henk Birkholz" initials="H." surname="Birkholz">
            <organization>Fraunhofer SIT</organization>
          </author>
          <author fullname="Thomas Fossati" initials="T." surname="Fossati">
            <organization>arm</organization>
          </author>
          <author fullname="Yogesh Deshpande" initials="Y." surname="Deshpande">
            <organization>arm</organization>
          </author>
          <author fullname="Ned Smith" initials="N." surname="Smith">
            <organization>Intel</organization>
          </author>
          <author fullname="Wei Pan" initials="W." surname="Pan">
            <organization>Huawei Technologies</organization>
          </author>
          <date day="4" month="March" year="2024"/>
          <abstract>
            <t>   Remote Attestation Procedures (RATS) enable Relying Parties to assess
   the trustworthiness of a remote Attester and therefore to decide
   whether to engage in secure interactions with it.  Evidence about
   trustworthiness can be rather complex and it is deemed unrealistic
   that every Relying Party is capable of the appraisal of Evidence.
   Therefore that burden is typically offloaded to a Verifier.  In order
   to conduct Evidence appraisal, a Verifier requires not only fresh
   Evidence from an Attester, but also trusted Endorsements and
   Reference Values from Endorsers and Reference Value Providers, such
   as manufacturers, distributors, or device owners.  This document
   specifies the information elements for representing Endorsements and
   Reference Values in CBOR format.

            </t>
          </abstract>
        </front>
        <seriesInfo name="Internet-Draft" value="draft-ietf-rats-corim-04"/>
      </reference>
    </references>
    <?line 293?>

<section numbered="false" anchor="acknowledgments">
      <name>Acknowledgments</name>
      <t>We sincerely thank contribution from NASR mailing list.</t>
    </section>
  </back>
  <!-- ##markdown-source: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-->

</rfc>
