sistent identifiers handle ark doi · RST .. _persistent-identifiers:

Persistent Identifiers: Handle vs. ARK vs. DOI¶

A guide for choosing the right identifier scheme for digital collections and repository content.

Why this matters¶

A persistent identifier (PID) is a long-lasting reference to a digital object. It is a link that keeps working even if the object’s URL changes. Handles, ARKs, and DOIs are the three schemes you’ll run into most often in library and archives work. They solve the same basic problem (link rot) but differ in who controls them, what they cost, what they imply about the resource, and what audience expects them.

Picking the wrong one isn’t fatal – you can usually mint more than one identifier for the same object – but it’s worth being deliberate, since it affects citation practice, discoverability, and long-term maintenance overhead.

The short version¶

	Handle	ARK	DOI
Full name	Handle System	Archival Resource Key	Digital Object Identifier
Governing body	Corporation for National Research Initiatives (CNRI) / DONA Foundation	California Digital Library (originally), now community-governed via the ARK Alliance	International DOI Foundation, via registration agencies (Crossref, DataCite, etc.)
Typical cost	Free if self-hosting a resolver; fees if using a Handle prefix service	Free – no central registry fees, though some assigners charge internally	Registration fees per DOI or per year, paid to a registration agency
Who mints them	Anyone running Handle server software with a prefix	Any organization with a Name Assigning Authority Number (NAAN)	Only registration-agency members (publishers, universities, data repositories, etc.)
Resolution	`hdl.handle.net` global resolver, or local resolver	`n2t.net` (Name-to-Thing) global resolver, or local resolver	`doi.org` global resolver
Implies scholarly citation?	Not inherently	Not inherently	Yes – DOIs carry strong expectations of formal, citable, versioned scholarly output
Common in	Institutional repositories (DSpace, Fedora, etc.)	Archives, special collections, digital library objects, cultural heritage	Journal articles, datasets, technical reports, anything meant to be formally cited
Metadata requirement	Minimal / none required by the system itself	Minimal / none required	Required – registration agencies mandate a metadata record (title, creator, publication date, etc.)

What each one actually is¶

Handle¶

A Handle is simply prefix/suffix (e.g., 2346/12345) that resolves through the Handle System to a URL. It’s infrastructure-level and deliberately unopinionated about what kind of resource it points to. DSpace repositories mint Handles by default for every item and collection, which is why they’re common for institutional repository content: theses, dissertations, technical reports, and other repository deposits.

Handles are a fine default when you need a stable identifier and don’t have a specific reason to reach for something more specialized. They don’t carry any implicit promise about formal citability or scholarly publication status. In other word,s they’re plumbing, not a statement.

ARK¶

An ARK looks like ark:/12345/x6f78d and is designed specifically for archival and cultural heritage contexts. Its design goals are notable: an ARK is meant to resolve not just to the object but optionally to a commitment statement (what the institution promises about the object’s persistence) and metadata (via appending ? or ?? to the identifier and a convention baked into the spec itself). That makes ARKs a natural fit for digital collections, digitized manuscripts, maps, photographs, and other special-collections material where you want the identifier itself to carry a bit of self-description.

ARKs are free to mint (you just need a NAAN, which is free to request), which has made them popular with archives and libraries that want persistent IDs without ongoing registration fees per object. This is a meaningful consideration at digitization scale, where you might be minting thousands of identifiers.

DOI¶

A DOI looks like 10.xxxx/yyyy and is built on top of the Handle System technically, but the social contract around DOIs is much stronger. Registering a DOI means committing to maintain a metadata record with a registration agency (Crossref for scholarly literature, DataCite for datasets and repository content, among others), and the DOI ecosystem assumes the object is a formally published, citable unit of scholarship. Getting a DOI typically costs money which can be per-DOI or membership fees through the registration agency.

Because of that infrastructure and expectation, DOIs are the right call when the object needs to be formally citable: journal articles, datasets tied to a publication, technical reports meant to be cited in the scholarly record.

Decision guide¶

Ask, in order:

Does this need to be formally, scholarly citable? The kind of thing someone will put in a reference list? → DOI. (This is really the deciding question. If yes, stop here.)
Is this a digitized cultural heritage object: a manuscript, map, photograph, or similar where you want the identifier to also carry a commitment/metadata statement, and you’re minting many of them without per-object fees? → ARK.
Is this a repository deposit (thesis, dissertation, report, dataset) where you just need a stable, resolvable link and your platform already mints these by default? → Handle.
Not sure, or it could go either way? → Default to whatever your platform issues natively (e.g., DSpace → Handle), and layer a DOI on top later if the object turns out to need formal citation. Identifiers aren’t mutually exclusive – the same object can have a Handle and a DOI.

A few practical notes¶

Note

You can have more than one. It’s common for an object to have a Handle (from the repository platform) and a DOI (for formal citation) simultaneously. The DOI becomes the “citable” identifier; the Handle remains the resolvable link within the repository ecosystem.

Warning

DOIs require upkeep. Once minted, DOI metadata has to stay accurate at the registration agency (title changes, corrections, etc.), and there’s an ongoing cost relationship with the registration agency. Don’t mint a DOI for something you don’t intend to maintain that record for.

ARKs’ optional inflections ( ? , ?? ) are a real feature, not decoration. If you’re choosing ARKs partly for their self-description properties, actually implement resolver support for the commitment and metadata suffixes – otherwise you’re just using an ARK as a plain identifier and losing the reason you picked it.
None of these prevent link rot on their own. They only work if someone maintains the resolver mapping. An identifier scheme is a governance commitment, not a technical guarantee.

Warning

DOIs are persistent identifiers (PIDs), which means that they are intended to be a permanent means of identifying and accessing a particular resource. Because of this, a DOI cannot be deleted and if it no longer resolves must point at a Tombstone page that explains why the resource is no longer available. If this happens, refer to the DataCite Best Practices.