Search for last-minute train slots (STDCM)
OSRD can be used to find a slot for a train in an already established timetable, without causing conflicts with other trains.
The acronym STDCM (Short Term Digital Capacity Management) is used to describe this concept in general. It’s sometimes called LMR (“last minute request”) when talking about the actual product in SNCF.
For video explanations, the subject has been explained twice at FOSDEM with replays available: in 2023 and in 2026. The first video focuses on the technical details, it’s quite old and thus incomplete, but only a few details are actually wrong. The second video does a quick explanation of the implementation, but focuses more on how it’s integrated in SNCF processes.
Note: some of the visuals here use the old OSRD interface, but they’re still relevant.
This website section is generally not updated very often, but the concepts
described here are general enough not to require frequent updates.
For a more accurate and in-depth explanation, check out the source code itself.
Or reach out to us on matrix.