Data Model

How Landblock structures land records — built on LADM (ISO 19152), the international standard for land administration.

Why LADM?

LADM (Land Administration Domain Model, ISO 19152) is the international standard for describing land rights, restrictions, responsibilities, parties, and spatial units. Building on LADM means Landblock records are semantically compatible with land administration systems worldwide — a Peruvian parcel and a German parcel use the same underlying data vocabulary.

Core entities

Spatial Unit (SpatialUnitRegistry)

A spatial unit is a physical piece of land — a parcel, plot, or zone. Each spatial unit is identified by a CoordsApp L1 URI: an immutable canonical coordinate reference with a checksum (coords:l1:v1:<lat>,<lng>,<alt>*<checksum>). Boundary coordinates are stored as GeoJSON, referenced by IPFS CID.

Spatial unit registrations go through a 72-hour challenge window and require 3-of-5 threshold signatures from authorized relayers before being finalized.

Basic Administrative Unit — BA Unit (BAUnitRegistry)

A BA unit is the legal administrative unit that land rights attach to. It links one or more spatial units to a set of rights, restrictions, and responsibilities. BA units support merge and split operations — when parcels are subdivided or consolidated, new BA units are created and the old ones are marked as superseded.

Rights, Restrictions & Responsibilities — RRR (RRRRegistry)

The RRR framework captures the full lifecycle of land rights. A right might be freehold title, leasehold, or customary tenure. A restriction might be a mortgage lien or a conservation easement. A responsibility might be a servitude or a public access obligation.

Each RRR record is linked to a BA unit, a party (rights-holder), and a temporal envelope. The full lifecycle — creation, transfer, amendment, extinguishment — is tracked as an append-only chain of records.

Party (IdentityRegistry)

A party is any person or organization that holds or is affected by a right. Parties are identified by DIDs (W3C Decentralized Identifiers). LADM party roles include ROLE_OWNER, ROLE_TRUSTEE, ROLE_MORTGAGEE, and custom roles defined by registry authorities.

Evidence (EvidenceStore)

Supporting documents — deeds, survey reports, boundary agreements — are stored off-chain on IPFS and Filecoin. The EvidenceStore records the IPFS CID on-chain with the full bitemporal temporal envelope. Evidence records can be linked to any spatial unit, BA unit, or RRR record.

Bitemporal temporal envelope

Every record carries three time dimensions:

• validTimeStart / validTimeEnd — when the fact was true in the real world (registry-asserted)
• systemTime — the UTC moment Landblock recorded the event
• blockTimestamp — Polygon validator timestamp (automatic)

Records also carry registryRecordedAt (the source registry's own timestamp) and supersedes (a reference to the prior record if this is a correction). Nothing is ever deleted — corrections create new records.

Global Directory (RegistryDirectory)

The RegistryDirectory is the on-chain index of all participating registries. Each entry records the registry's jurisdiction (ISO 3166-1 country code), conformance tier, status (active / inactive / contested), and federation relationships. Contested zones are tracked by coordinate range — Landblock makes no political assignment of disputed territory.