The transport system-based assignment is characterized by the following features.
- The run time of the procedure is short.
- The timetable (service frequency, transfer wait times) is not considered.
- Unrealistic route choice caused by frequent transfers within a transport system.
- Lines of the same transport system which run in parallel but have different PuT run times (for example bus 1 and bus 2) can only be represented by a mean PuT run time.
- The journey time or ride time can be estimated if PuT lines have short headways.
- Number of transfers, transfer wait time, and service frequency cannot be calculated.
- Results are not saved by path.
The assignment procedure based on transport systems is recommended for a first draft of a new line network. The procedure calculates the shortest routes (minimum time required) which are then charged with the travel demand. The resulting volume flows represent the "desired line network" of the passengers.
The volumes resulting from the timetable-based assignment and the headway-based assignment will differ significantly from the results calculated by the transport system-based assignment. Under no circumstances neither a timetable-based nor a headway-based calculation should be replaced by the transport system-based procedure.
