ISO 21219-2:2019

Overview

ISO 21219-2:2019 - “Intelligent transport systems - Traffic and travel information (TTI) via transport protocol experts group, generation 2 (TPEG2) - Part 2: UML modelling rules (TPEG2‑UMR)” defines the modelling rules and preferred specification structure for TPEG Generation 2 application UML models. The standard ensures UML models are unambiguous and machine‑interpretable so they can be converted reliably into physical format descriptions (e.g., binary and XML). Annexes provide the TPEG abstract data types and a set of commonly used TPEG tables.

Key topics and technical requirements

• UML modelling constraints and allowed elements - rules for Classes, Abstract classes, Attributes, Dependencies, Specializations, Stereotypes, Tagged values and Notes to ensure consistent modelling.
• Modelling rules and recommendations - guidance covering general modelling practice, order of elements, use of stereotypes, datatype usage, optional Booleans, tables and switching tables, inclusion of DataStructures and Components, linking abstract classes, graphical representation and documentation requirements.
• Extensibility rules - how to extend TPEG UML models while remaining interoperable and automatically convertible.
• Specification structure - preferred layout for TPEG application specifications to enable automated processing and clear normative content (e.g., class models, components, datatypes, tables).
• Machine conversion readiness - models defined to allow automatic generation of TPEG standard text and physical format descriptions (conversion toolchains often use UML XMI output).
• Normative annexes - TPEG abstract data types and a standard set of TPEG tables of common use included as normative material.

Practical applications and typical users

ISO 21219-2:2019 is intended for professionals who design, specify or implement traffic and travel information services (TTI) using TPEG2:

• Standards authors and technical editors drafting TPEG2 application specifications.
• Systems architects and data modelers creating UML models for TTI applications.
• Software and tool vendors implementing model‑to‑physical conversions (XMI → binary/XML) and automated documentation generators.
• Service providers, broadcasters and transport agencies deploying interoperable TPEG2 services, ensuring consistent encoding/decoding across platforms.
• Integrators and developers building decoders, encoders and content‑generation pipelines for dynamic travel information.

Related standards

• ISO/TS 21219‑1, ISO/TS 21219‑3, ISO/TS 21219‑4 and other parts of the TPEG2 toolkit that define the overall TPEG2 framework, conversion toolkits and location referencing methods.
• References to TPEG1 history and conversion targets (binary and XML physical formats) are addressed in the TPEG2 series.

Keywords: ISO 21219-2:2019, TPEG2, UML modelling rules, TPEG2-UMR, traffic and travel information, TTI, intelligent transport systems, UML XMI, binary/XML conversion.