BS EN ISO 14819-1:2021

What is ISO 14819‑1 about?  

The ALERT-C protocol is designed to provide mostly event-oriented road end-user information messages. 

BS EN ISO 14819‑1 specifies the messages which are presented to the user in accordance with a set of general requirements.  

BS EN ISO 14819‑1 defines the message structure and content and its presentation to the end-user. 

BS EN ISO 14819‑1 specifies the data specification for TTI messages, together with their network layer and their service layer, which shall be conveyed by the RDS-TMC feature. 

BS EN ISO 14819‑1 is based on the ALERT-C traffic message coding protocol, which was a product of DRIVE Project V1029, "RDS Advice and Problem Location for European Road Traffic". 

In BS EN ISO 14819‑1, Standard RDS-TMC user messages provide the following five basic items of explicit, broadcast information 

• Event description, giving details of road event situation, general traffic problems and weather Situations.  
• Location, indicating the area, road segment or point location where the source of the problem is situated. 
• Direction and extent, identifying the adjacent segments or specific point locations also affected by the incident, and where appropriate the direction of traffic affected. 
• Duration, giving an indication of how long the problem is expected to last. 
• Diversion advice, showing whether end-users are recommended to find and follow an alternative route. 

Who is ISO 14819‑1 for? 

BS EN ISO 14819‑1 on coding protocol for Radio Data System using ALERT-C is useful for: 

• Traffic management Department  
• European Broadcasting Union (EBU) 
• European Conference of Ministers of Transport (ECMT) 
• Service providers 
• Broadcasters 
• Travellers 

Why should you use BS EN ISO 14819‑1?  

Traffic and traveller information (TTI) can be disseminated through a number of services and means of communication to the end user, including static displays (e.g., variable message signs), broadcast audio to car radios, broadcast data services to in-vehicle equipment (e.g., installed navigation systems) and to nomadic device terminals (e.g., portable navigation device). 

For all such services, the data to be disseminated and the message structure involved in the various interfaces require clear definition and standard formats, in order to allow competitive products to operate with any received data. 

BS EN ISO 14819‑1 describes the data specification for TTI messages, together with their network layer and their service layer, which shall be conveyed by the RDS-TMC feature, specified in the IEC 62106 series. This enables the users with clear information related to the TTI messages.   

Due to the widespread adoption of the Radio Data System, in VHF/ FM broadcasting on Band II there is the possibility of transmitting coded TTI messages digitally and "silently" using the RDS-TMC feature, which avoids the interruption of planned programmes. 

This TTI delivery method has several advantages: TTI messages can be decoded into the language of the end user, regardless of location, more messages can be made available and planned broadcast programme interruption is avoided. Thus, using RDS-TMC makes the delivery of TTI messages timelier and more topical. 

The message management component of ISO 14819‑1 describes the message management functions of RDS-TMC. The ALERT-C protocol distinguishes between user messages and system messages, making it convenient for the users. 

The transmission component of ISO 14819‑1 conveys the messages over-air. The ALERT-C protocol, used by RDS-TMC, has the fundamental approach of aiming to code most messages entirely within a single RDS group. According to ISO 14819‑1 guideline, the RDS-ALERT project aimed to define standards for RDS-TMC, working in conjunction with the European Broadcasting Union (EBU) and the European Conference of Ministers of Transport (ECMT). 

What’s changed since the last update?  

BS EN ISO 14819‑1:2021 supersedes BS EN ISO 14819‑1:2013. BS EN ISO 14819‑1:2021 includes some technical changes with respect to BS EN ISO 14819‑1:2013. These include: 

• Additional tuning variants have been added to allow referencing of TMC services using the 64 MHz to 88 MHz band. 
• The method of encrypting an RDS-TMC service, previously separately specified in ISO 14819-6, has been merged into this document as Clause 8. Consequently, some renumbering of sections has occurred and encryption-specific terms, definitions and abbreviated terms have been added in Clause 3. 
• In some places the text has been improved and/or rearranged for greater clarity. Several typographical and grammatical errors have been corrected.