S-100: a framework for hydrographic data products
Understand S-100 as a framework for building interoperable hydrographic data products—not as one generic file format.
Why this matters
Maritime systems need to combine charts, depths, water levels, currents, and other information without every product inventing its own unrelated model. S-100 provides the common framework used to define those products.
Learn it
The IHO S-100 Universal Hydrographic Data Model is a framework based on the ISO 19100 family. An S-100-based product specification defines a particular data product and may include a machine-readable Feature Catalogue, Portrayal Catalogue, Data Classification and Encoding Guide, validation rules, and one or more encodings. Product specifications have editions and compatibility requirements, so implementation work must keep the exact product and edition with the data.
Work through an example
S-101 is an S-100-based product specification for Electronic Navigational Charts. S-100 tells you the framework; S-101 tells you the rules for that particular product.
Framework: S-100
Product specification: S-1xx
Edition/version: required context
Feature catalogue: feature + attribute meaning
Portrayal catalogue: display rules
Encoding: defined by the productPractice
- 1Given an unknown S-1xx dataset, identify the product specification and edition before mapping any fields.
- 2Find the feature catalogue and distinguish it from the portrayal catalogue.
- 3Write down which parts describe data meaning and which describe display.
What to watch for
Do not say 'S-100 format' as though one file layout defines every S-100 product. The product specification and edition are essential context.
Where this takes you
This mental model is useful when AtlasEvo or another GIS needs to preserve, inspect, map, or combine S-100-based content without losing product identity.