A typology of Space Research Infrastructures
draft-sastry-spacerg-space-research-infra-typology-00

Network Working Group                                          N. Sastry
Internet-Draft                                      University of Surrey
Intended status: Informational                              J. A. Fraire
Expires: 21 January 2027                                           Inria
                                                            20 July 2026

              A typology of Space Research Infrastructures
         draft-sastry-spacerg-space-research-infra-typology-00

Abstract

   Space networking research increasingly relies on a heterogeneous
   ecosystem of software, datasets, experimental platforms, reference
   implementations, and operational research assets.  These resources
   have historically been developed independently by different research
   groups, agencies, and projects, making discovery, comparison,
   interoperability, and reuse difficult.  Existing registries typically
   catalogue tools individually but provide limited guidance on their
   functional role within the research lifecycle.

   This document proposes a typology for research infrastructures
   relevant to the Space Research Group (SPACERG).  Rather than
   classifying resources according to implementation technology or
   project origin, the proposed taxonomy groups resources according to
   their research function.  The typology provides a common vocabulary
   for describing software and non-software research assets, supports
   the organization of community registries, and facilitates
   interoperability, reproducibility, and long-term maintenance of
   research infrastructures.  The classification is intended to evolve
   as new classes of research resources emerge.  The typology is
   implemented by a machine-readable registry of research resources
   maintained by the research group.

About This Document

   This note is to be removed before publishing as an RFC.

   The latest revision of this draft can be found at https://irtf-
   spacerg.github.io/id-leo-tools/draft-sastry-spacerg-space-research-
   infra-typology.html.  Status information for this document may be
   found at https://datatracker.ietf.org/doc/draft-sastry-spacerg-space-
   research-infra-typology/.

   Source for this draft and an issue tracker can be found at
   https://github.com/irtf-spacerg/id-leo-tools.

Sastry & Fraire          Expires 21 January 2027                [Page 1]
Internet-Draft                SpaceRG-Infra                    July 2026

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 21 January 2027.

Copyright Notice

   Copyright (c) 2026 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  The SPACERG Registry  . . . . . . . . . . . . . . . . . . . .   5
   3.  Conventions and Definitions . . . . . . . . . . . . . . . . .   5
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .   5
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   5
   6.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   5
     6.1.  Normative References  . . . . . . . . . . . . . . . . . .   5
     6.2.  Informative References  . . . . . . . . . . . . . . . . .   6
   Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . .   6
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   6

Sastry & Fraire          Expires 21 January 2027                [Page 2]
Internet-Draft                SpaceRG-Infra                    July 2026

1.  Introduction

   Research in space networking depends upon a broad collection of
   complementary research infrastructures.  These include simulation
   environments, network emulators, protocol implementations, datasets,
   browser-based experimentation environments, visualization tools,
   experimental testbeds, satellite constellations, and software
   supporting data collection and analysis.  While many of these
   resources have become widely adopted within individual research
   communities, they are often documented independently, use
   inconsistent terminology, and overlap in functionality.

   As the Space Research Group (SPACERG) develops a shared registry of
   research infrastructures, it has become apparent that simply
   maintaining a list of available tools is insufficient.  Users require
   a consistent method of understanding _what role_ a resource plays
   within the research ecosystem, how it complements other resources,
   and where it fits within an experimental workflow.  A common typology
   also improves discoverability, assists researchers in selecting
   appropriate infrastructures, and enables more consistent metadata
   across independently maintained registries.

   The typology described in this document was developed through an
   analysis of the more than 110 verified research resources collected
   from the community and curated in the SPACERG registry.  Rather than
   deriving categories from software architecture or implementation
   language, the classification emerged from the primary research
   purpose served by each resource.  This functional approach
   accommodates both software and non-software research assets and
   remains applicable as new technologies are introduced.

   The initial categories identified include, under the names used by
   the registry:

   *  *Simulator*, modelling network behaviour using abstract
      representations (flow-level, packet-level, or discrete-event) to
      support scalable experimentation without executing real protocol
      stacks.

   *  *Emulator*, reproducing the timing and topology of target systems
      while executing real protocol implementations and operating-system
      network stacks.

   *  *Testbed*, offering physical, virtual, or hybrid environments with
      real links, such as terminal deployments and ground stations, for
      integrated experimental evaluation.

Sastry & Fraire          Expires 21 January 2027                [Page 3]
Internet-Draft                SpaceRG-Infra                    July 2026

   *  *In-orbit platform*, representing operational or experimental
      space assets (research satellites, constellations, and hosted
      payloads) that provide real-world experimentation opportunities.

   *  *Dataset / data*, including curated measurement datasets and live
      data services such as orbital-element feeds.

   *  *Measurement*, providing tools and methodologies that produce new
      measurements, including browser-integrated extensions, terminal-
      telemetry collectors, Internet-scanning methodologies, and
      benchmarking frameworks.

   *  *Implementation*, providing runnable protocol stacks, proxies, and
      flight software deployed in experiments, such as Bundle Protocol
      implementations, non-terrestrial-network radio access stacks, and
      performance-enhancing proxies.

   *  *Library*, providing reusable building blocks embedded by other
      resources, such as orbit propagators, contact-plan generators, and
      routing libraries.

   *  *Visualizer*, supporting analysis, interpretation, and
      presentation of orbital and network state.

   *  *Research platform*, offering orchestration and service
      environments for experimentation, such as satellite edge-computing
      and serverless frameworks.

   The registry vocabulary additionally reserves a small set of
   auxiliary labels (Meta-resource, Commercial / service, Unresolved,
   Other) for resources that fall outside these research categories or
   that await classification.

   Although these categories provide broad coverage of the current
   SPACERG registry, they are not intended to be exhaustive.  New
   categories may emerge as the community develops additional research
   infrastructures, including digital twins, AI-assisted experimentation
   platforms, workflow management systems, and cloud-based
   experimentation environments.

   The purpose of this document is therefore not to prescribe a fixed
   ontology, but rather to establish a common vocabulary that enables
   researchers to consistently classify and discover research
   infrastructures relevant to space networking.  The taxonomy is
   intended to support the SPACERG registry, facilitate interoperability
   with other research infrastructure catalogues, and provide a
   foundation for future standardization efforts within the IRTF and
   IETF research communities.

Sastry & Fraire          Expires 21 January 2027                [Page 4]
Internet-Draft                SpaceRG-Infra                    July 2026

2.  The SPACERG Registry

   The typology in this document is implemented by a community registry
   maintained by SPACERG in the repository that also hosts this
   document, and published as a searchable page with JSON and CSV
   exports [REGISTRY].  Each resource is described by one machine-
   readable record carrying its class under this typology, functional
   metadata (how orbital dynamics are defined, which layers are covered,
   whether real protocol stacks are exercised, the largest scale
   demonstrated in a publication, and input and output formats), and
   provenance metadata (license, a named contact, how the entry was
   collected, and when it was last verified).

   Additions and corrections are made by pull request, one file per
   resource, and are validated automatically against the registry
   schema.  To be included, a resource should be specific to space or
   satellite networking, usable by others through a public artifact or a
   documented access program, and verifiable through a working URL and,
   where claims matter, a publication.

   Registry entries are point-in-time observations: tools are abandoned,
   URLs move, and maintenance states go stale.  Each record therefore
   carries a last-verified date and entries are re-verified
   periodically.  Entries that fail verification are marked as historic
   rather than deleted, because unmaintained resources remain relevant
   as baselines against which published results were obtained.

3.  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.

4.  Security Considerations

   TODO Security

5.  IANA Considerations

   This document has no IANA actions.

6.  References

6.1.  Normative References

Sastry & Fraire          Expires 21 January 2027                [Page 5]
Internet-Draft                SpaceRG-Infra                    July 2026

   [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>.

   [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>.

6.2.  Informative References

   [REGISTRY] IRTF Space Research Group, "SPACERG Space Networking Tools
              Registry",
              <https://irtf-spacerg.github.io/id-leo-tools/registry/>.

Acknowledgments

   TODO acknowledge.

Authors' Addresses

   Nishanth Sastry
   University of Surrey
   Email: n.sastry@surrey.ac.uk

   Juan A. Fraire
   Inria
   Email: juan.fraire@inria.fr

Sastry & Fraire          Expires 21 January 2027                [Page 6]