Overview
EN ISO 19128:2008 (ISO 19128:2005) - Web Map Server (WMS) interface - defines the behaviour of services that produce spatially referenced maps dynamically from geographic information. The standard specifies how clients and servers exchange requests and responses to describe available maps, retrieve rendered map images, and optionally query feature information shown on a map. It applies to pictorial map renderings (e.g., PNG, GIF, JPEG, SVG, WebCGM) and is explicitly not intended for retrieving raw feature data or coverage data values.
Key topics and requirements
- Core operations
- GetCapabilities (mandatory): returns service metadata and the server’s available Layers, Styles and supported coordinate reference systems (CRS).
- GetMap (mandatory): requests a rendered map image for a named Layer/Style with specified geographic bounding box, CRS, image size and format.
- GetFeatureInfo (optional): returns information about features at a user-specified location on a rendered map (queryable WMS only).
- Conformance classes
- Basic WMS: must implement basic service elements, GetCapabilities and GetMap.
- Queryable WMS: extends Basic WMS and must also implement GetFeatureInfo.
- Technical rules
- HTTP request/response patterns, URL parameter conventions and version negotiation.
- Supported output formats and MIME types for map images.
- Coordinate reference systems and coordinate handling (referencing ISO 19111, EPSG).
- Error/exception reporting, numeric/boolean parameter formats, and request parameter rules.
- Normative annexes
- Conformance tests, CRS definitions, multi-dimensional data handling, ISO 8601 profile, XML schemas and UML model, plus informative examples.
Applications
- Creating dynamic, on-the-fly map images for web mapping portals and GIS web services.
- Composing layered maps from distributed servers by overlaying transparent image formats.
- Supporting interoperable map delivery across government, environmental agencies, utilities, transportation and commercial GIS platforms.
- Enabling web clients (browsers, GIS desktop clients, mobile apps) to discover service capabilities and request maps using standardized URL-formatted requests.
Who uses this standard
- GIS software developers implementing WMS servers or clients.
- Web cartographers and spatial data infrastructure (SDI) architects integrating distributed map services.
- Organizations publishing maps online who need interoperable, standards-based map delivery.
Related standards
- ISO 19111 (spatial referencing by coordinates)
- ISO 19115 (geographic metadata)
- ISO 8601 (date/time)
- References: EPSG registry, HTTP (RFC 2616), XML Schema
- Note: OGC Styled Layer Descriptor (SLD) and Web Feature Service (WFS) are complementary specifications for user-defined styling and feature retrieval.
Keywords: EN ISO 19128, ISO 19128:2005, Web Map Service, WMS, web map server interface, geographic information, GetMap, GetCapabilities, GetFeatureInfo, map rendering.