Concept of Operations

Terrestrial analogue architecture for cislunar DTN communications.

The Concept

The terrestrial analogue architecture mirrors the cislunar communications path: Mission Operations Node → Ground/Gateway DTN Node → Amateur/experimental RF link → Relay/Remote DTN Node → Payload application endpoint. Each terrestrial demonstration exercises the same DTN protocols, store-and-forward behaviour, and contact scheduling that a cislunar mission would require, using amateur radio links as realistic disrupted-network analogues.

Sequence diagram showing DTN store-and-forward operation: Ground Station A uploads a bundle to the CubeSat during Pass 1, the bundle persists in non-volatile memory during a no-contact period, then the CubeSat forwards it to Ground Station B during Pass 2.

RF Link Types

The project uses a variety of amateur and experimental RF links as practical analogues for cislunar communication constraints:

  • Amateur radio LTP-over-KISS (VHF/UHF at 9600 baud, callsign in DTN EID)
  • Microwave point-to-point paths (10 GHz, 2.4 GHz)
  • Satellite-style scheduled links (QO-100 transponder)
  • EME-inspired operational patterns (moonbounce timing disciplines)
  • Weak-signal / intermittent links (troposcatter, aircraft scatter)

Contact Graph Routing

Bundles are routed through scheduled pass windows — CGR computes the optimal multi-hop path based on predicted contact times.

Contact graph routing diagram showing scheduled pass windows between Station A, a LEO CubeSat, and Station B over time, with CGR computing the route A to CubeSat via Contact 1, then CubeSat to B via Contact 2.

Why Amateur and Specialist Radio Communities Matter

These communities bring essential capabilities to the project:

Operation over difficult and intermittent RF paths

Disciplined link scheduling and station procedures

Experience with weak-signal and long-distance communication

Practical ground-segment engineering and experimentation

Collaborative culture suited to distributed demonstrations

Expected Outcomes

  • ✓A credible terrestrial analogue for cislunar DTN operations
  • ✓Operational evidence to support a flight experiment case
  • ✓Multi-node contact graph enabling distributed ground station routing and store-and-forward relay via LEO/GEO
  • ✓Automated contact plan distribution to all network nodes (API for ground, OTA bundles for space)
  • ✓Stronger links between space networking and specialist amateur-radio communities
  • ✓A clearer roadmap toward a cislunar payload demonstration of DTN-enabled networking

NASA References

Key NASA resources on Delay-Tolerant Networking and cislunar communications:

NASA Glenn: High-Rate Delay Tolerant Networking

NASA Glenn Research Center's HDTN programme page — architecture overview, capabilities, and mission context.

Delay/Disruption Tolerant Networking Tutorial

NASA educational resource introducing DTN concepts and architecture.

High-rate Delay Tolerant Networking (HDTN)

NASA Glenn's high-performance DTN software suite.

Delay/Disruption Tolerant Networking Overview

High-level overview of NASA's DTN programme.

NASA Delay Tolerant Networks: Operational, Evolving, and Ready for Expansion

Status report on NASA's operational DTN deployment.

A Communications Network for Cislunar Operations

NASA architecture for cislunar communication networks.