Traffic information is comprised of three main components:
- Where it is? – location. Messages that provide information about speed reductions or delays are most common. Where known, the cause of unexpected delays is explained (NB: no cause is given for routine or ‘peak-hour’ congestion). This explanatory information is provided to help you judge the significance of a delay.
- What the impact is – eg speed or delay. Coupled with your navigation device, only relevant information is drawn to your attention.
- What the cause is – eg accidents, road works, lane closures. The international TMC standard enables us to broadcast messages with a certain ‘granularity’ or geographic resolution. Generally, the finest resolution that can be supported for messages on arterial roads is between intersections with other main roads where there are traffic lights. This works fine for navigation purposes, but explains why a traffic event may show across a length of road between intersections, even if it is really only at a point along the road.