Current laboratory work

NetSatBench and ION-DTN

A bounded record of DTN lab scaffolds and current work aligning orbital calculations, NetSatBench link events, and ION contact knowledge.

Problem

NetSatBench controls when the emulated IP links exist and which delay/rate conditions Linux applies. ION-DTN stores and forwards bundles using its own configuration and contact knowledge. The integration task is to derive both timelines from the same declared scenario and keep physical quantities, encoded values, and measured results separate.

Earlier synthetic lab scaffold

The repository first used a six-node synthetic topology to prepare comparable command flows for ION-DTN, uD3TN, HDTN, and DTN7-go. Linux namespaces, veth links, and tc/netem provide scheduled connectivity. The common scaffold exists, but a controlled cross-stack benchmark and comparative result table are still planned.

Current NetSatBench–ION path

1. Declared inputsA controlled circular-reference scenario or separately identified ephemeris input, ground nodes, RF assumptions, and timing policy.
2. Derived geometrySatellite position, AOS/LOS, slant range, physical OWLT = ρ/c, and candidate link rate.
3. Synchronized artifactsNetSatBench link add/update/delete epochs and ION contact/range plus per-node .ionrc, .bprc, and .ipnrc files share one T₀.
4. RuntimeNetSatBench realizes VXLAN, /32 routing, and tc/NetEm state; ION handles BPv7, IPN forwarding, storage, and the UDP-based BP convergence-layer adapter.
5. EvidenceLogs, configuration snapshots, selected PCAPs, file integrity checks, and explicitly defined metrics support individual claims.

Reference calculation

The controlled eight-satellite model uses a 1200 km circular altitude, WGS-84 equatorial radius, and a 25° elevation mask. The code derives a 6565.301 s Kepler period, 45° phase spacing, 5800.055 km adjacent-ISL chord, 623.149 km chord clearance, and 19.347 ms adjacent-ISL OWLT. This is a calibrated reference model, not an operational OneWeb or Starlink specification.

Important boundaries

• The physical OWLT remains ρ/c. In selected tests, subsecond delay was applied through NetEm while ION's whole-second range field used 0 s as an encoding workaround; this does not mean zero propagation delay.
• The current baseline uses ION's UDP-based BP convergence-layer adapter. LTP is not part of the retained baseline.
• Generated contact plans and successful delivery do not by themselves prove that CGR selected a particular route.
• The eight-satellite circular reference, a later ONEWEB-0012 SGP4 exercise, and any planned Starlink V2 Mini work are separate scenario identities.

Status