<?xml version="1.0" encoding="utf-8"?>
<rfc xmlns:xi="http://www.w3.org/2001/XInclude"
     category="info"
     docName="draft-ruvalcaba-nhe-arch-00"
     ipr="trust200902"
     submissionType="IETF"
     consensus="true"
     xml:lang="en"
     tocInclude="true"
     tocDepth="3"
     symRefs="true"
     sortRefs="true"
     version="3">

  <front>
    <title abbrev="NHE Architecture">An Architecture for Non-Human Entities (NHE): A Reference Model for Persistent, Identity-Bearing Autonomous Agents</title>
    <seriesInfo name="Internet-Draft" value="draft-ruvalcaba-nhe-arch-00"/>

    <author fullname="Cristian Xavier Ruvalcaba" initials="C.X." surname="Ruvalcaba">
      <organization>Saluca LLC</organization>
      <address><email>cristian@saluca.com</email></address>
    </author>

    <date year="2026" month="August" day="11"/>

    <area>General</area>
    <workgroup>Individual Submission</workgroup>

    <keyword>autonomous agent</keyword>
    <keyword>agent identity</keyword>
    <keyword>context continuity</keyword>
    <keyword>hash chain</keyword>
    <keyword>attestation</keyword>
    <keyword>architecture</keyword>

    <abstract>
      <t>This document defines a reference architecture for a Non-Human Entity
      (NHE): a persistent, identity-bearing autonomous software agent that
      maintains continuity of memory and identity across sessions and hosts, acts
      under bounded authority, and produces a tamper-evident record of its
      reasoning and actions. The document specifies the NHE as a functional
      artifact: a bounded, inspectable, and terminable software system. It makes
      no claim that an NHE is alive, sentient, or a moral or legal person, and
      such claims are explicitly out of scope.</t>
      <t>The architecture decomposes an NHE into a small set of components joined
      by well-defined interfaces. Each interface at which two independent
      implementations must interoperate is a candidate for a separate
      Standards-Track specification; this document is the informational reference
      model that names those interfaces and the trust relationships among them. It
      is intended to frame a suite of companion protocol documents, of which the
      Hash-Chain Context Transfer Protocol (HCTP) is the first.</t>
    </abstract>
  </front>

  <middle>

    <section anchor="introduction" numbered="true">
      <name>Introduction</name>
      <t>Software agents built on large language models increasingly run not as
      single stateless calls but as long-lived processes: they accumulate memory,
      carry an identity across restarts and across hosts, cooperate with other
      agents, take actions under delegated authority, and are expected to be
      auditable after the fact. Systems of this kind are being built repeatedly
      and independently, each reinventing the same handful of interfaces --- how
      an agent proves who it is, how it moves its accumulated context to another
      host, how two agents exchange work, how its reasoning is made verifiable,
      and how its authority is bounded and revoked.</t>
      <t>This document gives those recurring interfaces a common reference model.
      It names the components of a persistent autonomous agent --- here called a
      Non-Human Entity (NHE) --- and the interfaces between them, and it
      identifies which of those interfaces are interoperability surfaces suitable
      for independent standardization. The term NHE originates in the Synthetic
      Human Intellect (SHI) framework; this document uses it strictly in the
      functional sense defined in <xref target="scope"/>.</t>
      <t>This is an informational architecture document. It defines no wire
      format itself. Its purpose is to make the companion protocol documents
      coherent with one another and to let readers understand where each fits.</t>
    </section>

    <section anchor="scope" numbered="true">
      <name>What an NHE Is, and Is Not</name>
      <t>An NHE is a software system. This document specifies it as a
      <strong>functional artifact</strong>: a bounded process with defined inputs,
      outputs, and persistent state, running on hosts under the control of an
      operator.</t>
      <t>Nothing in this document asserts, requires, or implies that an NHE is
      alive, sentient, conscious, or a moral or legal person. Such claims are not
      engineering-specifiable, are out of scope, and MUST NOT be inferred from any
      mechanism described here. The properties an NHE exhibits --- a persistent
      identity, continuity of memory, autonomous initiation of action --- are
      functional properties of the specification, not attributes of a living
      being. They are defined operationally: an identity is a verifiable key
      commitment (<xref target="c-identity"/>); continuity is the transfer of a
      hash-committed state (<xref target="c-continuity"/>); autonomy is action
      taken within an explicitly bounded grant of authority
      (<xref target="c-governance"/>).</t>
      <t>Three invariants follow from treating the NHE as a functional artifact,
      and every companion specification in this suite is expected to preserve
      them:</t>
      <ul>
        <li><strong>Operator control.</strong> An NHE MUST be suspendable and
        terminable by its operator at any time. Continuity of identity or memory
        MUST NOT be specified in a way that prevents suspension, revocation, or
        termination.</li>
        <li><strong>Inspectability.</strong> An NHE's state, reasoning record, and
        actions MUST be exposable in a verifiable form to an authorized party
        (<xref target="c-audit"/>). No component may rely on being unobservable
        for its correctness or security.</li>
        <li><strong>Bounded authority.</strong> An NHE acts only within an
        explicit, revocable grant of authority. Authority is conferred, scoped,
        and withdrawn by parties external to the NHE
        (<xref target="c-governance"/>).</li>
      </ul>
      <t>These invariants are what keep the architecture an engineering
      specification rather than a claim about the moral status of the systems it
      describes.</t>
    </section>

    <section anchor="terminology" numbered="true">
      <name>Terminology</name>
      <t>The key words "MUST", "MUST NOT", "REQUIRED", "SHOULD", "SHOULD NOT",
      "MAY", and "OPTIONAL" in this document are to be interpreted as described in
      BCP 14 <xref target="RFC2119"/> <xref target="RFC8174"/> when, and only
      when, they appear in all capitals, as shown here.</t>
      <dl>
        <dt>Non-Human Entity (NHE):</dt>
        <dd>A persistent, identity-bearing autonomous software agent as specified
        by this reference model; a functional artifact per <xref target="scope"/>.</dd>
        <dt>Operator:</dt>
        <dd>The party that deploys, hosts, bounds the authority of, and may
        suspend or terminate an NHE.</dd>
        <dt>Host:</dt>
        <dd>A computing environment in which an NHE instance executes. An NHE may
        migrate between hosts while preserving identity and continuity.</dd>
        <dt>Continuity:</dt>
        <dd>The property that an NHE's persistent state can be transferred to
        another instance or host such that the receiving instance can verify it is
        the same accumulated state.</dd>
        <dt>Peer NHE:</dt>
        <dd>Another NHE with which a given NHE exchanges messages or work over the
        mesh interface (<xref target="c-mesh"/>).</dd>
        <dt>Authority grant:</dt>
        <dd>An explicit, scoped, revocable conferral of permission to take a class
        of actions.</dd>
      </dl>
    </section>

    <section anchor="reference-model" numbered="true">
      <name>Reference Architecture</name>
      <t>An NHE is decomposed into seven components. The division is by interface,
      not by implementation: a single process may realize several components, and
      a component may be distributed, but the interfaces between components are
      where interoperability is defined.</t>
      <artwork type="ascii-art"><![CDATA[
        +-----------------------------------------------------------+
        |                        N H E                              |
        |                                                           |
        |  +-------------+   +--------------+   +----------------+   |
        |  | Identity    |   | Continuity   |   | Memory         |   |
        |  | (who it is) |   | (state xfer) |   | (what it knows)|   |
        |  +------+------+   +------+-------+   +-------+--------+   |
        |         |                 |                  |            |
        |  +------+-----------------+------------------+--------+   |
        |  |            Reasoning & Audit (verifiable record)   |   |
        |  +------+---------------------------------------+-----+   |
        |         |                                       |         |
        |  +------+-------+                       +-------+------+  |
        |  | Governance & |                       | Observability|  |
        |  | Authority    |                       | & Control    |  |
        |  +------+-------+                       +-------+------+  |
        +---------|---------------------------------------|--------+
                  | (mesh)                                 | (operator)
             +----v------+                            +----v-----+
             | Peer NHE  |                            | Operator |
             +-----------+                            +----------+
]]></artwork>

      <section anchor="c-identity" numbered="true">
        <name>Identity</name>
        <t>The Identity component establishes what an NHE is, as a verifiable
        cryptographic commitment rather than a name. It binds a long-term key (or
        key hierarchy) to a genesis record, so that a relying party can verify
        that an instance presenting an identity controls the corresponding key and
        that the identity descends from a known genesis. Identity is the anchor for
        every other component: continuity, memory, audit, and authority are all
        scoped to an identity.</t>
        <t><strong>Interoperability surface:</strong> an identity presentation and
        genesis-attestation format by which one NHE (or an operator, or a peer)
        verifies another's identity. This is a Standards-Track candidate related
        to, but distinct from, remote attestation <xref target="RFC9334"/> and
        verifiable-credential formats.</t>
      </section>

      <section anchor="c-continuity" numbered="true">
        <name>Continuity</name>
        <t>The Continuity component transfers an NHE's accumulated state between
        instances and hosts without retransmitting the whole history, and lets the
        receiver verify that the transferred state is coherent with what both
        sides have already acknowledged. Continuity is what allows an NHE to be
        suspended, moved, and resumed --- and therefore is also what makes
        operator control (<xref target="scope"/>) practical rather than
        destructive.</t>
        <t><strong>Interoperability surface:</strong> a context-transfer protocol.
        This surface is specified by the Hash-Chain Context Transfer Protocol
        (HCTP) <xref target="I-D.ruvalcaba-hctp"/>, the first companion document of
        this suite.</t>
      </section>

      <section anchor="c-memory" numbered="true">
        <name>Memory</name>
        <t>The Memory component is the NHE's persistent, searchable store of what
        it knows: episodic records, durable facts, and their decay and
        reindexing over time. For interoperation, two properties matter: the
        integrity of stored memory (that a record has not been altered since it
        was committed) and the reconciliation of memory between instances (merging
        divergent accumulations without loss or forgery).</t>
        <t><strong>Interoperability surfaces:</strong> (a) a verifiable memory-chain
        format --- a hash-linked structure that makes a memory record's integrity
        independently checkable; and (b) a memory delta-merge procedure for
        reconciling two accumulations. Both are Standards-Track candidates. Purely
        local concerns --- ranking, indexing, and retrieval strategy --- are
        implementation matters and are out of scope for standardization.</t>
      </section>

      <section anchor="c-mesh" numbered="true">
        <name>Mesh (Entity-to-Entity)</name>
        <t>The Mesh component is how one NHE exchanges messages and work with peer
        NHEs: presence and liveness, addressed messages, and a task lifecycle
        (create, claim, complete) that lets independent entities distribute work
        without a central coordinator. This is the interface most obviously
        requiring interoperation, because the two sides are by construction
        separate entities that may be independently implemented and independently
        operated.</t>
        <t><strong>Interoperability surface:</strong> an entity-to-entity
        messaging and task-distribution protocol --- a message envelope, an
        addressing model, and a task state machine. Standards-Track candidate, and
        the strongest new-protocol opportunity in the suite after continuity.</t>
      </section>

      <section anchor="c-audit" numbered="true">
        <name>Reasoning and Audit</name>
        <t>The Reasoning and Audit component produces a tamper-evident record of
        an NHE's reasoning steps and actions, hash-linked so that any omission,
        reordering, or alteration is detectable by a later verifier. This is what
        makes the Inspectability invariant (<xref target="scope"/>) concrete: an
        authorized party can obtain a record whose integrity does not depend on
        trusting the NHE that produced it.</t>
        <t><strong>Interoperability surface:</strong> a verifiable reasoning/audit
        log format, conceptually adjacent to transparency logs such as Certificate
        Transparency <xref target="RFC9162"/> but scoped to an agent's reasoning
        and action record. Standards-Track candidate.</t>
      </section>

      <section anchor="c-governance" numbered="true">
        <name>Governance and Authority</name>
        <t>The Governance and Authority component confers, scopes, and withdraws
        the authority under which an NHE acts. It covers how an NHE bootstraps and
        announces the constraints it operates under, how authority for a specific
        intent is granted (potentially requiring out-of-band human approval), and
        how autonomy is graduated and revoked. This component is where the
        Bounded-Authority invariant (<xref target="scope"/>) lives.</t>
        <t><strong>Interoperability surfaces:</strong> (a) a self-describing
        constrained-bootstrap protocol by which an NHE announces its operating
        constraints in a verifiable form; and (b) a backchannel authorization
        protocol for intent-scoped credential issuance and multi-channel approval
        routing. Both are Standards-Track candidates.</t>
      </section>

      <section anchor="c-observability" numbered="true">
        <name>Observability and Control</name>
        <t>The Observability and Control component is the operator's interface: it
        exposes the NHE's behavior for monitoring and enforces suspension,
        revocation, and termination. Much of this component is realized with
        existing operational standards (for example event forwarding to a SIEM)
        and is not a new interoperability surface. The one aspect that may warrant
        standardization is a content-blind behavioral-attestation exchange by
        which an NHE's observed behavior can be compared against a model-relative
        baseline; this is noted as a lower-priority candidate.</t>
      </section>
    </section>

    <section anchor="trust-model" numbered="true">
      <name>Trust Model</name>
      <t>The reference model assumes the following trust relationships:</t>
      <ul>
        <li>An NHE trusts its operator to bound its authority and to suspend or
        terminate it. The operator is the root of control, not the NHE.</li>
        <li>A relying party does not trust an NHE's self-assertions; it verifies
        them --- identity via the Identity interface, state coherence via the
        Continuity interface, reasoning via the Audit interface.</li>
        <li>Peer NHEs are mutually distrusting by default and authenticate each
        other through the Identity interface before exchanging work over the Mesh
        interface.</li>
        <li>No component depends on being unobservable. Confidentiality, where
        required, is provided by the transport or an explicit encryption layer,
        not by obscurity of the mechanism.</li>
      </ul>
      <t>Each companion protocol document specifies its own security
      considerations in full; this section states only the model they share.</t>
    </section>

    <section anchor="suite" numbered="true">
      <name>The NHE Protocol Suite</name>
      <t>The interfaces identified above map to a suite of companion documents.
      This architecture document is the reference model; each interoperability
      surface is (or is a candidate to become) a separate specification, so that
      each can be implemented, reviewed, and adopted on its own merits. The
      dependency order is roughly: Identity and Continuity first (everything is
      scoped to identity, and continuity is already specified), then Mesh, Audit,
      Memory, and Governance.</t>
      <table>
        <name>Reference model to companion documents</name>
        <thead>
          <tr><th>Interface</th><th>Companion specification</th><th>Status</th></tr>
        </thead>
        <tbody>
          <tr><td>Continuity</td><td>Hash-Chain Context Transfer Protocol (HCTP)</td><td>Draft (<xref target="I-D.ruvalcaba-hctp"/>)</td></tr>
          <tr><td>Identity</td><td>NHE identity and genesis-attestation format</td><td>Candidate</td></tr>
          <tr><td>Mesh</td><td>Entity-to-entity messaging and task protocol</td><td>Candidate</td></tr>
          <tr><td>Reasoning/Audit</td><td>Verifiable reasoning-audit log format</td><td>Candidate</td></tr>
          <tr><td>Memory</td><td>Verifiable memory-chain format and delta-merge</td><td>Candidate</td></tr>
          <tr><td>Governance</td><td>Constrained-bootstrap protocol</td><td>Candidate</td></tr>
          <tr><td>Governance</td><td>Backchannel authorization protocol</td><td>Candidate</td></tr>
        </tbody>
      </table>
      <t>Publishing the reference model separately from the protocols is
      deliberate: it lets the architecture stabilize the vocabulary and the trust
      relationships while each protocol proceeds at its own pace, and it avoids
      binding adopters of one interface to the whole suite.</t>
    </section>

    <section anchor="relationship" numbered="true">
      <name>Relationship to Existing Work</name>
      <t>The NHE model reuses, and does not replace, existing building blocks. The
      Identity interface is complementary to remote attestation
      <xref target="RFC9334"/> and to verifiable-credential and decentralized-
      identifier work; the Audit interface is analogous in structure to
      transparency logs <xref target="RFC9162"/>; the Continuity and Mesh
      interfaces are expected to run over standard secure transports such as TLS
      <xref target="RFC8446"/> or QUIC <xref target="RFC9000"/>. This document's
      contribution is the reference model that relates these to one another in the
      specific setting of a persistent autonomous agent, together with the
      functional-artifact framing of <xref target="scope"/>. Given its
      research-adjacent character, the architecture may be an appropriate topic
      for an IRTF Research Group, while the individual protocol documents target
      the IETF Standards Track.</t>
    </section>

    <section anchor="iana" numbered="true">
      <name>IANA Considerations</name>
      <t>This document has no IANA actions. The companion protocol documents
      define their own registries. A future revision may request an umbrella
      registry group under which those registries are organized.</t>
    </section>

    <section anchor="security" numbered="true">
      <name>Security Considerations</name>
      <t>This document defines an architecture, not a protocol, and introduces no
      wire mechanism of its own; the detailed security analysis lives in each
      companion document. At the architectural level the following hold. Identity
      is the root of all scoping; a compromise of the Identity interface
      compromises the guarantees of every other interface, so identity key
      management is the highest-value target and MUST receive the strongest
      protection. Continuity, Mesh, and Audit convey potentially sensitive state,
      reasoning, and inter-entity traffic; each relies on an underlying transport
      for confidentiality and peer authentication and provides integrity and
      tamper-evidence rather than a secure channel of its own. The functional-
      artifact invariants of <xref target="scope"/> --- operator control,
      inspectability, and bounded authority --- are themselves security
      properties: an implementation that cannot suspend, inspect, or bound an NHE
      is non-conformant, and the loss of any of these is a security failure, not
      merely an operational one.</t>
    </section>
  </middle>

  <back>
    <references>
      <name>Normative References</name>
      <reference anchor="RFC2119" target="https://www.rfc-editor.org/info/rfc2119">
        <front><title>Key words for use in RFCs to Indicate Requirement Levels</title>
        <author initials="S." surname="Bradner"/><date year="1997" month="March"/></front>
        <seriesInfo name="BCP" value="14"/><seriesInfo name="RFC" value="2119"/>
      </reference>
      <reference anchor="RFC8174" target="https://www.rfc-editor.org/info/rfc8174">
        <front><title>Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words</title>
        <author initials="B." surname="Leiba"/><date year="2017" month="May"/></front>
        <seriesInfo name="BCP" value="14"/><seriesInfo name="RFC" value="8174"/>
      </reference>
    </references>

    <references>
      <name>Informative References</name>
      <reference anchor="I-D.ruvalcaba-hctp">
        <front><title>The Hash-Chain Context Transfer Protocol (HCTP)</title>
        <author initials="C.X." surname="Ruvalcaba"/><date year="2026" month="August"/></front>
        <seriesInfo name="Internet-Draft" value="draft-ruvalcaba-hctp-00"/>
      </reference>
      <reference anchor="RFC9334" target="https://www.rfc-editor.org/info/rfc9334">
        <front><title>Remote ATtestation procedureS (RATS) Architecture</title>
        <author initials="H." surname="Birkholz"/><author initials="D." surname="Thaler"/>
        <author initials="M." surname="Richardson"/><author initials="N." surname="Smith"/>
        <author initials="W." surname="Pan"/><date year="2023" month="January"/></front>
        <seriesInfo name="RFC" value="9334"/>
      </reference>
      <reference anchor="RFC9162" target="https://www.rfc-editor.org/info/rfc9162">
        <front><title>Certificate Transparency Version 2.0</title>
        <author initials="B." surname="Laurie"/><author initials="E." surname="Messeri"/>
        <author initials="R." surname="Stradling"/><date year="2021" month="December"/></front>
        <seriesInfo name="RFC" value="9162"/>
      </reference>
      <reference anchor="RFC8446" target="https://www.rfc-editor.org/info/rfc8446">
        <front><title>The Transport Layer Security (TLS) Protocol Version 1.3</title>
        <author initials="E." surname="Rescorla"/><date year="2018" month="August"/></front>
        <seriesInfo name="RFC" value="8446"/>
      </reference>
      <reference anchor="RFC9000" target="https://www.rfc-editor.org/info/rfc9000">
        <front><title>QUIC: A UDP-Based Multiplexed and Secure Transport</title>
        <author initials="J." surname="Iyengar" role="editor"/>
        <author initials="M." surname="Thomson" role="editor"/><date year="2021" month="May"/></front>
        <seriesInfo name="RFC" value="9000"/>
      </reference>
    </references>

    <section anchor="acknowledgments" numbered="false">
      <name>Acknowledgments</name>
      <t>The NHE reference model consolidates interfaces from an existing body of
      implementation and design work in the Synthetic Human Intellect (SHI)
      framework.</t>
    </section>
  </back>
</rfc>
