These telematic devices publish the current traffic information for the drivers directly to the road using variable traffic sign pictograms or text messages on variable message signs of traffic information devices.

The information published automatically using these technologies is the fastest published information about a critical incident in general.

By the end of 2010, almost 100 TIE units will be installed along D and R type roads in the Czech Republic.

A variable message sign can display 3 lines of 15 characters of text. The text contains information about the stationing of an incident spot or section and on the scope of limitation or on the specific measure taken.

Some text information displayed by TIE are complemented with one of the eight VTS pictograms.

The texts published by TIEs may be divided into four basic groups:

  • preplanned events (closings, repair and maintenance works, construction works),
  • unpredictable situations (accident, traffic obstacle, immobile vehicle, etc.),
  • weather attack (wind, visibility, precipitation, road passability),
  • traffic intensity increase (heavy traffic, queue formation).

Some message signs show travel time estimations for distant destinations when the traffic is fluent. The travel time estimations are calculated based upon a certain model and the current traffic data. In reality, the travel time may change with the actual traffic situation development as unpredictable limiting incidents may occur during the journey.

Apart from TIE and VTS, motorways and roads are equipped with individual VTS with automatic warnings, such as black ice warnings. Digital thermometers and other telematic devices are installed.