ISO 14819-3:2013 pdf free

ISO 14819-3:2013 pdf free.Intelligent transport systems – Traffic and travel information messages via traffic message coding
the successful use of the table and associated TMC service. A new version of an existing location table must remain compatible with the previous versions of the same location table一the changes must not be such that the location of a TMC message could be wrongly interpreted by a receiver. For example, location codes which are deleted should not be used for a long period. Also changing the attributes class and type of a location might cause an incompatible version of the table. It is part of TISA’s location certification process to judge if a table is backwards compatible.
The method for identifying and labelling different versions of a location table is shown in Annex C.3.1 TISA has established an allocation of location tables to show which are in use or available for use in each country. The responsible agency in a country can apply for additional location table numbers in future, to support further applications or more detailed, regional location tables. New tables can also be issued occasionally to allow for complete updates to existing tables. Such major changes will however be very disruptive for users, as existing receivers will not recognise TMC messages relating to the new location table unless the same location table is also installed in the receiver. Switches from one location table to a different one (rather than a new version of the same table) should therefore be avoided as far as possible, especially in established markets.
For TMC services to work well, the different organisations involved need to be able to understand the location table number, version and contents. To achieve this, a Location Table Exchange Format has been defined.
This format will be used for the exchange of TMC Location Tables between the various functional areas, e.g.receiver manufactures, map providers, certification of TMC location tables, Traffic Information Centres and service providers.ISO 14819-3 pdf download.