Matching involves merging timetable data and real-time data. As the public transport sector in Switzerland (still) does not have a universally valid, cross-system benchmark to support both data sources, matching is a delicate operation to some extent. One of the guarantees provided by matching is that harmonised, good-quality information is made available on the output channels.
There is the principle that matching must be so robust that it continues to provide sensible output, even if only timetable data or real-time day are available. Adhering to this principle as far as possible requires a deep understanding of journey planning and timetable data, as well as of assignment and real-time data. This is the reason why matching is carried out via the Open Data Platform.
Different forms of matching can be carried out from a technical perspective. Referencing is the first step carried out using a journey ID (FahrtID). This is given, for instance, for the normal-gauge railway. If this JourneyID is not provided, different parameters from both data sources need to be matched:
- Stops: This does not apply in Switzerland as the DiDok number is generally used. Only the difference between a stop and stopping point must be taken into account. But as the stopping point contains a DiDok number, it will definitely be derived again.
- Transport companies: The process for matching transport companies is carried out indirectly via line/direction
- Line and Direction: Line and direction are used to match the journeys. As the lines are differentiated from each other on the basis of association with a transport company, the transport companies are also matched with each other indirectly in this way.In the case of VDV 431, the result is then the JourneyRef as a trip reference.
- Within the line/direction assigned to each other, an algorithm supplied by the supplier tries to search for and match identical journeys.