The Participant Relationship Protocol (PRP): A Relationship-Centric Network Architecture
draft-alves-prp-architecture-00
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Author | Gustavo Junior Alves | ||
| Last updated | 2026-08-22 | ||
| RFC stream | Independent Submission | ||
| Intended RFC status | (None) | ||
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| Stream | ISE state | Submission Received | |
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draft-alves-prp-architecture-00
Network Working Group G. J. Alves
Internet-Draft GJ LABS
Intended status: Informational 22 August 2026
Expires: 23 February 2027
The Participant Relationship Protocol (PRP): A Relationship-Centric
Network Architecture
draft-alves-prp-architecture-00
Abstract
This document describes the architecture of the Participant
Relationship Protocol (PRP). PRP treats a relationship, rather than
an address, route, transport connection, or identity alone, as the
primary persistent context in which communication is authorized and
continuity is evaluated. It separates relationships from the
replaceable identities, sessions, trajectories, routes, paths,
adjacencies, transports, and carriers that realize communication.
PRP is independent of IP and of any other particular network-layer
protocol. IP-based and non-IP carriers are optional realizations of
the same relationship-centric architecture.
The document defines terminology, architectural invariants, layering
boundaries, security and privacy requirements, and criteria for
evaluating relationship-centric protocol designs. It intentionally
does not define a wire format, cryptographic suite, routing
algorithm, carrier technology, deployment architecture, or IANA
registry.
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-
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Internet-Drafts are draft documents valid for a maximum of six months
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on 23 February 2027.
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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.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3
3. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Foundational Model . . . . . . . . . . . . . . . . . . . . . 4
5. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
5.1. Reference Classes . . . . . . . . . . . . . . . . . . . . 6
6. Architectural Invariants . . . . . . . . . . . . . . . . . . 7
6.1. Relationship Primacy . . . . . . . . . . . . . . . . . . 7
6.2. Independent Lifetimes . . . . . . . . . . . . . . . . . . 7
6.3. Local Scope . . . . . . . . . . . . . . . . . . . . . . . 8
6.4. Explicit Authority . . . . . . . . . . . . . . . . . . . 8
6.5. Replaceable Realization . . . . . . . . . . . . . . . . . 8
6.6. No Mandatory Global Infrastructure . . . . . . . . . . . 8
6.7. Network-Layer Independence . . . . . . . . . . . . . . . 8
7. Architectural Layers . . . . . . . . . . . . . . . . . . . . 8
8. Conceptual Operation . . . . . . . . . . . . . . . . . . . . 9
9. Illustrative Use Cases . . . . . . . . . . . . . . . . . . . 10
9.1. Mobility across Realizations . . . . . . . . . . . . . . 10
9.2. Intermittent Communication . . . . . . . . . . . . . . . 10
9.3. Scoped or Pseudonymous Participation . . . . . . . . . . 10
10. Discovery, Routing, and Aggregation . . . . . . . . . . . . . 10
11. Relationship to Existing Network Architectures . . . . . . . 11
12. Security Considerations . . . . . . . . . . . . . . . . . . . 12
13. Privacy Considerations . . . . . . . . . . . . . . . . . . . 12
14. Operational Considerations . . . . . . . . . . . . . . . . . 13
15. Extensibility and Evolution . . . . . . . . . . . . . . . . . 13
16. Architectural Conformance . . . . . . . . . . . . . . . . . . 14
17. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
18. Normative References . . . . . . . . . . . . . . . . . . . . 14
19. Informative References . . . . . . . . . . . . . . . . . . . 14
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 15
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 15
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1. Introduction
Internet communication is commonly described through addresses,
routes, transport state, and application endpoints. Those objects
are necessary realization mechanisms, but none of them alone
expresses the durable authorization and continuity context between
communicating participants. Addresses can change, paths can fail,
transport sessions can be rekeyed, and carrier attachments can
disappear while the reason and authorization for communication
remain.
PRP introduces the relationship as an explicit architectural object.
A relationship records the rules under which participants recognize
continuity, constrain identity, authorize communication, and replace
realization mechanisms. Reachability can make communication
technically possible, but it does not create or expand relationship
authority.
The foundational statement of PRP is:
| Communication becomes possible because a relationship already
| exists.
This is an architectural ordering rather than a claim that packets
can be exchanged before reachability exists. Paths, transports, and
carriers move information, while routes select scoped forwarding
outcomes. The relationship determines why an exchange belongs to a
continuing authorized context and which realization mechanisms are
acceptable for that context.
This document is intended for protocol designers, implementers,
researchers, and reviewers evaluating relationship-centric
networking. It is published for informational purposes through the
Independent Submission Stream and does not represent IETF consensus
or specify an Internet Standard.
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.
3. Scope
This document defines:
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* the relationship-centric communication model;
* the distinction among relationships, identities, sessions,
trajectories, routes, paths, adjacencies, transports, and
carriers;
* architectural layers and dependency boundaries;
* continuity, authorization, and trust invariants;
* security and privacy properties that every realization must
address; and
* requirements for claiming architectural conformance.
This document does not define packet or record layouts, cryptographic
algorithms, numeric registries, session-establishment messages,
routing or discovery algorithms, carrier bindings, application object
models, deployment mechanisms, or administrative interfaces.
Separate specifications may define those subjects provided they
preserve the invariants in this document.
4. Foundational Model
An address-centric communication sequence is often summarized as:
address -> route -> transport -> communication
PRP instead places the relationship and its continuity rules before
the realization mechanisms:
relationship -> continuity and authorization
^
|
trajectory / route decisions / transport / carrier
The relationship does not replace the lower-layer mechanisms. It
supplies the persistent context against which their use, replacement,
and failure are evaluated. A realization can therefore move between
addresses, paths, sessions, or carriers without silently creating a
new relationship, provided continuity is authenticated under
relationship policy.
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5. Terminology
Participant:
An entity capable of taking part in a relationship. A participant
can represent a person, process, service, device, organization, or
another entity type.
Relationship:
A persistent communication and authorization context among
participants. Persistence is semantic and does not require a
particular storage mechanism or uninterrupted availability.
Continuity:
The ability to determine, under relationship policy, whether an
interaction belongs to the same relationship across time or a
change of realization mechanism.
Identity:
A representation by which a participant or service can be
distinguished within a defined scope. An identity constraint is
relationship policy specifying which identity properties are
required, permitted, or prohibited.
Trust material:
Information used to evaluate continuity, authorization, or
identity constraints. Transport reachability alone is not trust
material unless relationship policy explicitly makes it so.
Authorization boundary:
The set of actions permitted within a relationship.
Authentication evaluates a principal or continuity claim;
authorization determines what that claim is allowed to do.
Session:
Bounded cryptographic and operational state used to exchange
information within a defined scope and generation. A relationship
can use multiple sessions over its lifetime.
Route:
A scoped directional forwarding decision used in the realization
of a trajectory. A route selects an eligible next path,
adjacency, or local-delivery outcome. It is one decision leg of a
trajectory and is not the trajectory itself.
Trajectory:
A validated directional realization of reachability for a
relationship. A trajectory can span multiple route decisions and
contains one or more paths.
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Path:
An authenticated directional opportunity to carry traffic within a
trajectory.
Routing identifier:
An operational selector for local route state, interpreted within
an explicit routing scope and lifetime.
Adjacency:
A context in which participants can directly exchange units
through a carrier under a defined local scope. Physical proximity
or carrier enumeration can create an adjacency candidate but does
not establish an authenticated relationship.
Transport:
The exchange semantics used to realize a relationship, including
the applicable authentication, confidentiality, integrity, replay,
ordering, and reliability properties.
Carrier:
A mechanism capable of moving protocol units between adjacent
participants. Carrier technology and locators are realization
details.
Service:
A capability exposed within an authorization context above core
relationship semantics. Discovery, governance, evaluation,
storage, and application protocols can be services without
becoming prerequisites of every deployment.
Aggregation:
An optional relationship-realization arrangement in which an
authorized participant coordinates or intermediates multiple
independently authorized relationship contexts or trajectories.
Aggregation does not merge relationships, identities, continuity
state, or authorization boundaries. It is distinct from packet
batching, data summarization, and group identity.
Aggregator:
A participant performing aggregation under explicitly delegated
relationship authority. Acting as an aggregator grants no
implicit authority over endpoint identity, relationship
continuity, or application authorization.
5.1. Reference Classes
A protocol realization can distinguish several non-substitutable
reference classes:
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* A strong identifier is a self-certifying reference to one concrete
entity.
* A strong alias is an authenticated logical reference whose
selected concrete members still prove their own strong
identifiers.
* A weak alias is a classification reference and is not a
cryptographic identity.
* A content identifier is an immutable commitment to finite content
bytes and is not an entity identity.
A content identifier has no private key, cannot prove possession, and
does not assert an owner, author, provider, or semantic meaning.
Availability of matching bytes is a separate and revocable claim.
Specific encodings and algorithms for these classes are outside this
architecture.
6. Architectural Invariants
6.1. Relationship Primacy
A conforming design MUST identify the relationship context whose
communication it realizes. It MUST NOT define relationship
continuity solely as continued possession of a locator, route,
carrier attachment, or ephemeral session handle.
6.2. Independent Lifetimes
Relationships, identities, sessions, trajectories, routes, paths,
adjacencies, and carriers have distinct lifetimes. A conforming
design MUST define transitions among them without silently equating
one object with another.
* A relationship can outlive a session, trajectory, route, path, or
carrier.
* A trajectory can be replaced and its route decisions can change
without replacing the relationship.
* A session can be rekeyed without changing participant identity.
* An adjacency can exist without authorization to form a
relationship.
* Loss of a carrier does not by itself revoke a relationship.
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6.3. Local Scope
Operational selectors are local unless another authenticated scope is
explicitly defined. Local selectors MUST NOT be interpreted as
global addresses or identities. An intermediary can rewrite local
forwarding selectors while preserving end-to-end relationship
semantics.
6.4. Explicit Authority
Every protocol decision affecting access to a relationship or service
MUST derive from relationship policy or explicitly delegated
authority. Reachability, routing, discovery results, or a successful
cryptographic handshake MUST NOT silently expand authorization.
6.5. Replaceable Realization
A conforming design SHOULD support replacement of a failed or
obsolete realization mechanism without replacing the relationship
when continuity can be authenticated. When continuity cannot be
authenticated, the design MUST fail or establish a new relationship
according to explicit policy. It MUST NOT silently reset replay,
ordering, identity, or authorization state while claiming continuity.
6.6. No Mandatory Global Infrastructure
A conforming protocol suite MUST permit two participants possessing
sufficient local relationship information and a compatible carrier to
communicate without consulting a mandatory global naming, routing,
identity, governance, or ledger service. A profile can depend on
external services, but that dependency is a property of the profile
and not a universal architectural requirement.
6.7. Network-Layer Independence
The PRP architecture MUST NOT require IPv4, IPv6, or any other
particular network-layer protocol as a universal prerequisite. A
conforming realization can operate over any compatible carrier
capable of moving protocol units between adjacent participants.
A profile MAY require IP or another network technology. That
dependency is a property of the profile, not of PRP itself. When an
IP-based profile is used, IP addresses and routing are scoped
realization mechanisms and MUST NOT become participant identity,
relationship continuity, or authorization.
7. Architectural Layers
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1. The relationship layer defines continuity, trust, authorization,
and communication permissions.
2. The routing layer selects and maintains trajectories and the
scoped route decisions that realize a relationship.
3. The transport layer supplies exchange semantics over those
trajectories.
4. The carrier layer moves units between adjacent participants.
Services operate above these concerns. A protocol can combine layers
in one component, message, or cryptographic transcript, but it MUST
retain their semantic boundaries.
A function belongs to the architectural core only when every valid
deployment requires it, it cannot be supplied as an optional service,
and omitting it would invalidate the relationship-centric model.
8. Conceptual Operation
This section is non-normative. It illustrates the distinction
between a relationship and its realizations without prescribing
messages or implementation components.
1. Participants possess local policy and trust material sufficient
to recognize or propose a relationship.
2. A carrier supplies an adjacency candidate, eligible paths are
authenticated, and scoped route decisions participate in a
selected trajectory.
3. A protocol profile authenticates the required principals and
binds a session to the relationship context.
4. Authorized services exchange information through that session.
5. If a path, trajectory, carrier, or session fails, another
realization can be established. The relationship continues only
if its continuity rules are satisfied.
6. Revocation of the relationship authorization terminates its
authority independently of whether old trajectories, route
decisions, or sessions remain technically usable.
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This sequence does not require a globally resolvable participant
name. A selected profile can require a self-certifying identity, a
provisioned trust anchor, a pseudonymous continuity key, or another
explicitly specified mechanism.
9. Illustrative Use Cases
This section is non-normative. The examples illustrate consequences
of the architecture and do not prescribe protocol mechanisms or
deployment models.
9.1. Mobility across Realizations
Two participants communicate while one moves between carrier
attachments and receives different locators. Paths and transport
state can be replaced, but the relationship need not be recreated.
The replacement is accepted only when the selected profile
authenticates continuity and preserves the relationship's
authorization constraints.
9.2. Intermittent Communication
Participants can retain a relationship while no valid trajectory,
path, or compatible carrier is available. Later reachability
supplies a new opportunity to communicate; it does not by itself
restore authority. Communication resumes only after continuity is
established under the relationship policy.
9.3. Scoped or Pseudonymous Participation
A relationship can constrain a participant to a scoped or
pseudonymous identity without requiring a globally resolvable name or
civil identity. The scope, acceptable identity evidence, and
authorized actions remain explicit properties of that relationship.
The absence of a global name does not imply anonymity or prevent
correlation.
10. Discovery, Routing, and Aggregation
Discovery produces candidates or information used to realize a
relationship. It does not establish identity, trust, continuity, or
authorization unless a separate authenticated procedure explicitly
says so.
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Routing constructs and maintains trajectories through scoped
directional route decisions. A relationship can be direct or transit
one or more forwarding participants. Transit does not grant an
intermediary authority over endpoint identity or application
authorization.
Aggregation is an optional scaling and privacy mechanism. Direct
relationships remain architecturally valid. An aggregation profile
MUST specify what an aggregator learns, which statements it
authenticates, and which decisions remain reserved to endpoints. It
MUST preserve the independent relationship, identity, continuity, and
authorization boundaries defined by this architecture.
11. Relationship to Existing Network Architectures
PRP is independent of the Internet Protocol. It does not require
IPv4, IPv6, or any other particular network-layer protocol. A PRP
realization can operate over any compatible carrier capable of moving
protocol units between adjacent participants.
An IP-based profile can use IP addresses, routing, and transport
protocols as optional realization mechanisms. IPv6 continues to
provide packet delivery as described in [RFC8200] when such a profile
uses it. This does not make IP an architectural prerequisite, and
possession of an IP address does not establish participant identity,
relationship continuity, or authorization.
Transport protocols already separate some connection state from a
particular path. For example, QUIC supports connection migration
[RFC9000]. That continuity is transport-specific; PRP defines a
relationship context that can outlive and authorize replacement of
the complete transport session.
Other architectures separate endpoint identity from routing location.
The Host Identity Protocol [RFC7401] introduces a host identity
namespace, while the LISP architecture [RFC9299] separates endpoint
identifiers from routing locators. PRP does not replace those
mechanisms. It distinguishes both identity and locator from the
relationship that determines continuity and authorization, and a PRP
profile can use such mechanisms as realizations.
The architecture therefore does not claim that identity-locator
separation, path migration, or authenticated sessions are new
individually. Its contribution is the explicit relationship object
and the invariants that prevent those replaceable mechanisms from
becoming implicit sources of persistent authority.
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12. Security Considerations
Relationship primacy does not itself provide cryptographic security.
Every protocol profile MUST specify authenticated principals and
transcript scope, confidentiality and integrity properties, replay
domains, authorization inputs, selector and generation scopes, key
and state lifetimes, exhaustion and amplification bounds, downgrade
protection, and failure behavior.
A carrier-security claim does not imply end-to-end security.
Adjacent authentication does not imply service authorization. A
self-certifying identifier demonstrates control of key material but
does not establish an external civil identity or authorize arbitrary
services.
Continuity creates valuable long-lived state and is therefore a
target for fixation, rollback, replay, and confused-deputy attacks.
A replacement realization MUST be bound to the exact relationship,
participants, direction, generation, and authorization policy
required by its profile. State from one scope MUST NOT be admitted
into another merely because identifiers or byte lengths coincide.
Unknown or malformed security-critical values MUST fail closed unless
a specification defines a safe extension rule. Loss of continuity
evidence MUST NOT be repaired by silently accepting reachability, a
local handle, or unauthenticated forwarding state as equivalent
authority.
Persistent relationships can increase the impact of compromised trust
material. Profiles must define revocation, recovery, key
replacement, and the point at which continuity can no longer be
safely claimed. Denial-of-service protections must bound retained
state, verification work, retries, referrals, and fanout per
authenticated authority.
13. Privacy Considerations
Relationship-centric operation does not inherently provide anonymity,
unlinkability, traffic-flow confidentiality, resistance to
correlation, or availability. A stable relationship context can
itself become a correlation surface even when routes, addresses, and
session keys change.
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Profiles MUST state which relationship identifiers, participant
references, timing signals, path changes, and service metadata are
visible to carriers, intermediaries, discovery services, and peers.
Operational selectors should have the narrowest practical scope and
lifetime. Implementations should avoid exposing durable relationship
state where an ephemeral correlation is sufficient.
Padding, batching, multipath, private discovery, aliases, and cover
traffic can reduce particular observations, but each requires
separate analysis. No deployment should infer privacy properties
merely from the absence of globally meaningful addresses or civil
identities.
14. Operational Considerations
Relationship, trajectory, route-decision, path, session, and carrier
state should be observable as distinct objects so that operators do
not mistake path availability for relationship authorization.
Diagnostics should identify scope and generation while avoiding
disclosure of long-lived trust material or globally correlatable
identifiers.
Implementations need explicit bounds for relationship state,
candidate trajectories and paths, route decisions, concurrent
sessions, retained replay information, and recovery attempts.
Replacement should normally be make-before-break when the selected
profiles can authenticate continuity, but an implementation must
prefer loss of availability over an unauthorized continuity claim.
Interoperability depends on protocol profiles that instantiate this
architecture. Architectural conformance alone does not imply wire
compatibility.
15. Extensibility and Evolution
Extensions MUST preserve the invariants in this document. An
extension that requires globally stable locators, equates routes with
identity, or makes optional governance a universal prerequisite is
not architecturally conforming.
Protocol versions and profiles MUST define explicit selection and
failure behavior. Negotiation MUST NOT silently weaken authenticated
properties or reinterpret assigned values. Migration SHOULD preserve
relationship continuity through an authenticated make-before-break
procedure when both profiles permit it.
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16. Architectural Conformance
A design conforms to this architecture only if it:
1. treats a relationship as the primary persistent communication and
authorization context;
2. defines continuity independently of any single trajectory, route,
path, session, or carrier;
3. keeps operational routing and carrier selectors distinct from
identity;
4. makes authorization an explicit relationship decision;
5. permits direct communication without mandatory global governance;
6. does not make IP or another particular network-layer protocol a
universal prerequisite;
7. states the scope and lifetime of identities, sessions,
trajectories, routes, paths, and selectors; and
8. does not claim security or privacy properties beyond those
supplied by specified profiles.
Conformance to this architecture does not imply conformance to a
particular wire protocol, discovery mechanism, routing protocol,
carrier binding, or service profile.
17. IANA Considerations
This document has no IANA actions.
18. 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>.
[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>.
19. Informative References
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[RFC7401] Moskowitz, R., Heer, T., Jokela, P., and T. Henderson,
"Host Identity Protocol Version 2 (HIPv2)", RFC 7401,
DOI 10.17487/RFC7401, April 2015,
<https://www.rfc-editor.org/info/rfc7401>.
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
[RFC9000] Iyengar, J. and M. Thomson, "QUIC: A UDP-Based Multiplexed
and Secure Transport", RFC 9000, DOI 10.17487/RFC9000, May
2021, <https://www.rfc-editor.org/info/rfc9000>.
[RFC9299] Cabellos, A. and D. Saucez, "An Architectural Introduction
to the Locator/ID Separation Protocol (LISP)", RFC 9299,
DOI 10.17487/RFC9299, October 2022,
<https://www.rfc-editor.org/info/rfc9299>.
Appendix A. Acknowledgments
The author thanks the contributors and implementers whose independent
protocol work exposed the architectural distinctions documented here.
Specific reviewers will be acknowledged in subsequent revisions.
Author's Address
Gustavo Junior Alves
GJ LABS
Email: gjalves@gjalves.com.br
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