An RAT stores route attributes. There is one RAT for each route-system in a coverage. In addition to user-defined attributes, an RAT contains a sequence number and feature identifier for each route. See also route-system , section , SEC , and feature attribute table . A location along a route, defined as a measure from a start point, where measures include distance, time, milepost, address range.
Measures are useful for locating events along a route.
There may be more than one start or end within a route, in which case, the measures may not be unique within a route-system. For example, there are many places that are within a one-minute response time from a fire station. A collection of routes representing separate instances of a common linear entity, for example, all school bus routes in a city. A single line coverage can contain many route-systems, differentiated by name. Both an RAT and an SEC exist for each route-system.