Skip to main content
Research preview — APIs may change. GitHub

​
Location Data

Location data is what Astral operates on. Every API call starts with spatial data — points, polygons, lines, or references to previously recorded locations. But not all location data is created equal. The provenance of a piece of location data determines how much trust you can place in it.

​
The Verifiability Spectrum

Astral works with location data at three levels of verifiability:
LevelWhat it isWhat you know
Raw GeoJSONUnsigned geospatial dataThe vector geometry itself — nothing about who created it or whether it’s been tampered with
Signed location recordEAS attestation with cryptographic signatureWho attested to this location, plus assurances that data hasn’t been changed
Location proofSigned location record + evidence from proof-of-location systemsAll of the above, plus independently evaluable evidence about a claim about the location of an event
Each level adds verifiability. Raw GeoJSON is fine for some use cases; signed location records add attribution and integrity. Location proofs add evidence of physical correspondence — the hardest part. Astral doesn’t take a stance on what’s trustworthy — that’s not our role. Instead, we provide a system to organize, harmonize, and evaluate location data and evidence — to make spatial decision parameters legible – so that applications can make informed, risk-appropriate choices about what to trust and how much.
v0 supports vector geospatial data only. Raster support (GeoTIFFs, imagery analysis) is planned.

​
Geospatial data sources

Location data comes from many sources, each with different properties:
  • Device sensors — GPS, Wi-Fi, cellular positioning. Ubiquitous but often spoofable.
  • Network infrastructure — Cell tower triangulation, IP geolocation, internet latency measurements. Coarse but hard to manipulate without network access.
  • Hardware attestation — Secure enclave readings, hardware keystores. Harder to forge but still device-dependent.
  • Institutional records — Land registries, shipping manifests, IoT telemetry. Trusted because of the institution, not cryptography.
  • Reference data — Official boundaries, standard geometries, public datasets. Trusted because they’re publicly auditable.
No single source is sufficient for high-stakes applications. Location proofs address this through defense-in-depth: combining evidence from multiple independent sources to raise the cost of forgery.

​
Coordinate system

All location data in v0 of the Astral Protocol uses GeoJSON as the geometry format. Coordinates follow the GeoJSON standard:
  • Default Coordinate Reference System (CRS): WGS84 (http://www.opengis.net/def/crs/OGC/1.3/CRS84)
  • Coordinate order: [longitude, latitude] — note that this is the opposite of what many mapping APIs use (a common challenge in GIS systems — here’s why.)

Next: GeoJSON

Raw unsigned geospatial data
See also: