Overview
CEN ISO/TS 18234-4:2006 defines the Road Traffic Message (RTM) application for Transport Protocol Expert Group (TPEG) data‑streams. Part of the broader Traffic and Travel Information (TTI) family, this Technical Specification describes the method for delivering efficient, language‑independent road traffic messages from service providers to end‑users. It covers event and status information that affects road journeys, including incidents, lane closures and limited operational details of transport links (e.g., ferries, lifting bridges).
Key topics and technical requirements
- TPEG application architecture: RTM is one of several TPEG applications and is identified by a unique Application ID (AID).
- Three information containers:
- Message Management Container (message lifecycle, dates/times, severity, reliability).
- Application Event Container (event types and structured event descriptions).
- TPEG‑Location Container (location referencing - specified in CEN ISO/TS 18234‑6).
- Byte‑oriented data streams: TPEG uses a byte‑oriented stream format suitable for multiple digital bearers and broadcast channels.
- Language independence: Messages are encoded to enable human‑readable output in different languages and machine parsing for agent systems.
- Interoperability and backward compatibility: RTM was designed with awareness of RDS‑TMC to ease transition and enable automatic generation of legacy messages where feasible.
- Message elements covered: event classification, date/time fields, severity and reliability indicators, location referencing strategy, and message management semantics.
Practical applications and users
CEN ISO/TS 18234‑4:2006 is intended for organizations implementing real‑time traffic and travel services:
- Traffic data service providers and broadcasters (DAB, digital radio, streaming data).
- Navigation system manufacturers and in‑vehicle infotainment vendors integrating live traffic alerts.
- Mobile app developers that ingest TPEG‑RTM streams for routing and notifications.
- Fleet and logistics operators using standardized traffic feeds for route optimization.
- Map data vendors and ITS integrators for consistent location referencing and event encoding.
- Public authorities and traffic management centers distributing standardized road status information.
Practical use cases include live incident alerts, dynamic rerouting, congestion and roadworks notifications, and cross‑platform sharing of road network status.
Related standards
Keywords: TPEG, TTI, RTM, ISO/TS 18234‑4:2006, road traffic message, location referencing, message management container, traffic alerts, transport protocol.
