Persistent Identifiers and DOIs
A persistent identifier is a stable, resolvable name for a digital object that keeps pointing to it even as locations change.
Names that do not break
A web link can rot: the page moves, the server changes, and the reference dies. A persistent identifier (PID) solves this by separating the name of a thing from its current location. The identifier is stable and resolvable; a resolution service maps it to wherever the object currently lives. This is what makes long-term citation possible.
The DOI
The Digital Object Identifier is the most common PID for scholarly outputs, including datasets. A DOI is a string that resolves through a central system to the object's landing page. It is registered with metadata, so a DOI carries not just a location but a description, authorship, and links to related works. DOIs are widely used to cite deposited data.
Other identifiers
- ORCID: a persistent identifier for a researcher.
- ROR: an identifier for a research organization.
- Handle: the general system DOIs are built on.
- Content hashes: identify data by its exact bytes (see data integrity).
Why PIDs matter for FAIR
Findability, the first FAIR principle, depends on a globally unique, persistent identifier. A dataset with a DOI can be cited precisely, discovered through indexes, and relied on to remain reachable. Without a PID, a dataset is only as findable as a fragile link. See FAIR principles.
In the Kronos record
The Kronos published simulation datasets are deposited to a persistent archive that mints DOIs, so each paper's supporting data has a stable, citable identifier that resolves regardless of how the hosting evolves. Versioned deposits get their own identifiers, so a citation can point to an exact version rather than a moving target, supporting reproducibility.