Overview
EN ISO 19125-1:2006 (ISO 19125-1:2004) - Geographic information - Simple feature access - Part 1: Common architecture - defines a common architecture and vocabulary for simple feature geometry used in GIS, spatial databases and geospatial APIs. The standard establishes a Distributed Computing Platform (DCP)‑neutral, UML‑based geometry object model that standardizes names and geometric definitions for Geometry Types (Point, Curve, Surface, GeometryCollection and their multi‑variants) and associates each geometry with a Spatial Reference System (SRS).
Key takeaways:
- Standardizes geometry type names and definitions for interoperability.
- Is intentionally neutral about how geometry types are implemented, stored, added or maintained.
- Provides representations and interfaces (e.g., Well‑Known Text/Binary are described in the standard) to support data exchange.
Key Topics
- Geometry object model: Base Geometry class and subclasses (Point, Curve, Surface, GeometryCollection), plus MultiPoint, MultiLineString, MultiPolygon, MultiCurve and MultiSurface for collection semantics.
- Spatial Reference Systems (SRS): Association of each geometry with an SRS (SRID concept) to define coordinate space.
- Representations: Includes Well‑Known Text (WKT), Well‑Known Binary (WKB) and textual SRS representations to aid portability.
- Conformance: Implementations conform by satisfying test suites specified in other parts of ISO 19125 (e.g., Part 2 SQL option).
- Standards alignment: Implements a profile of ISO 19107 (Spatial schema) and references ISO 19111 (spatial referencing by coordinates).
- DCP‑neutral & UML: Architecture is independent of specific APIs or middleware (COM, CORBA, SQL, etc.) and expressed using UML.
Applications
EN ISO 19125-1:2006 is fundamental for:
- Designing and documenting spatial database schemas and user defined geometry types.
- Building GIS software, spatial APIs and libraries that must interoperate with other systems.
- Implementing data exchange formats and services using WKT/WKB or SRID metadata.
- Creating test suites and conformance frameworks for spatial implementations.
Practical benefits:
- Improved interoperability between GIS vendors, spatial DBMSs and applications.
- Clear mapping between geometry semantics and spatial reference metadata.
- Consistent foundation for higher‑level options (SQL option - Part 2) and platform bindings.
Who should use this standard
- GIS developers and architects
- Spatial DBMS vendors and integrators
- Data modelers and geospatial standards teams
- Organizations implementing interoperable geospatial services or data exchange pipelines
Related standards
Keywords: EN ISO 19125-1:2006, ISO 19125-1, simple feature access, geometry object model, spatial reference system, WKT, WKB, spatial database, GIS interoperability.
