ukmesh/docs/link-model.md

Link Model

Purpose

node_links represents the physical or physically-rated link graph used by the map and the path resolver.

Evidence layers

The model distinguishes between:

• physical feasibility
  • terrain
  • path loss
  • LOS tolerance
• radio-neighbour evidence
  • repeater-reported neighbour quality
• packet evidence
  • strongest: multibyte path evidence
  • weaker: generic packet observation

Worker ownership

The worker computes:

• terrain profile
• total path loss
• viability

Relevant files:

• viewshed-worker/rf/config.py
• viewshed-worker/rf/loss.py
• viewshed-worker/rf/terrain.py
• viewshed-worker/worker.py in WORKER_MODE=link

Practical tuning knobs

• LINK_LOS_MAX_V
• DEFAULT_USABLE_PATH_LOSS_DB
• calibration controls in rf/config.py
• RF_PREFIX_ENDPOINT_BATCH and RF_PREFIX_RAY_BATCH for bounded CPU/memory tuning
• frontend display bands in frontend/src/components/Map/mapConfig.ts

Contributor rule

Do not treat packet observation counts as if they are the same thing as physical feasibility. If a change affects topology definition, make sure the evidence class is explicit.

Whole-region RF coverage is a separate HopReach raster pipeline and does not consume the link worker's former viewshed polygons. Its capacity evidence, source boundary, and rollout gate are in docs/rf-coverage-rollout.md.