Transferring between services
If there is no direct SERVICE JOURNEY between the origin and the destination SCHEDULED STOP POINTs of a trip, a passenger will have to interchange between vehicles. The passenger will alight from the vehicle making a SERVICE JOURNEY at a particular SCHEDULED STOP POINT and transfer to board another vehicle (performing another SERVICE JOURNEY, usually on a different LINE) at the same or another SCHEDULED STOP POINT.
The transfer takes place at a CONNECTION. A CONNECTION indicates that two specified SCHEDULED STOP POINTs are suitably located for it to be possible for a passenger to walk between them when making an interchange from one public transport vehicle to another; it can also allocate specific time for a passenger to traverse the link (if note given, these may be defaulted from a DEFAULT CONNECTION or SITE CONNECTION). It is independent of any specific SERVICE JOURNEY.
If two specific SERVICE JOURNEYs are intended to coincide at a possible CONNECTION point, this can be expressed by a SERVICE JOURNEY INTERCHANGE.
Each SERVICE JOURNEY INTERCHANGE involves two different SERVICE JOURNEYs. The passenger makes the transfer from a feeder SERVICE JOURNEY to a distributor (or “fetcher”) SERVICE JOURNEY.
Sometimes a SERVICE JOURNEY INTERCHANGE expresses an “interchange“ between two SERVICE JOURNEYs specifically planned to be operated by the same physical vehicle. This concept is for instance used for circular lines and coupled journeys. This means that passenger information should indicate that the passenger does not need to change vehicle as the transfer is implicit (see the StaySeated attribute below).