THEME 1 Aims: What do you want to achieve by implementing Persistent Identifiers?
Position 1
My Persistent Identifiers are in place so that researchers can cite and reference works.
Answer
DataCite DOIs are designed for reference and citation of material, and are known and accepted as best practice in research communities. URN:NBNs are primarily designed for identification, and less so for citation purposes. Handles are an all purpose persistent identification system and generally useful assigning identifiers to a large number of digital objects. (If you strongly agree, then this doubles your score in favour of Datacite DOI for this question, because of Datacite DOI's focus on scientific data citation.)
Position 2
My Persistent Identifiers are meant for machine readable use, for example with aggregation services such as Europeana or in APIs.
Answer
If the main goal is that aggregators such as Europeana and Digitale Collectie Nederland can always track and find your object, then Handle is probably the best choice for you. You can also use DataCite DOIs and URN:NBNs, however these focus more on citation than the machine readable aspects.
Position 3
My Persistent Identifiers are meant to support the scientific and academic research process.
Answer
Whenever you aim to link Persistent Identifiers to stages in the input or output, or to various steps in your data workflows, then you aim to make your research as transparent and reproducible as possible. Handles lend themselves to this type of process. Whereas DOIs and URN:NBNs are better linked to finished, published datasets.
Position 4
I want to be able to make my own policies regarding Persistent Identifiers.
Answer
The more freedom you require in terms of policy creation, the more internal regulation you will have to govern and maintain. URN:NBNs and DataCite DOIs have clear (and strict) policies, while choosing Handles means you are quite free to create you own policies.
Position 5
The digital objects connected to my Persistent Identifiers must be in a (certified) Trustworthy Digital Repository. The repository must aim to provide long term sustainable access to digital objects.
Answer
DataCite DOIs and Handles don’t require the digital objects to be in a Trusted Digital Repository, but it is recommended. URN:NBNs however, do require that objects are housed in such a repository. (If you strongly agree with this statement, then this doubles your score in favour of URN:NBNs for this question, because of this URN:NBN requirement.)
THEME 2 Context: What type of objects are you creating Persistent Identifiers for?
Position 6
The objects are predominantly (written) publications such as books, newspapers magazines, etc.
Answer
With URN:NBNs the emphasis is on the sustainability of publications, data(sets) and accompanying metadata. A URN:NBN is therefore ideal to link to publications. DataCite DOIs are, as the name suggests, generally suited to pointing to (scientific) data and datasets. Handles can be applied to individual objects (i.e files or scans). (If you strongly agree with this statement, then this doubles your score in favour of URN:NBNs for this question. because of URN:NBN's emphasis.)
Position 7
The digital objects are predominantly physical objects, such as museum artefacts, (analogue) photos or books.
Answer
DataCite DOIs support the identification of physical objects, with Handles you need to have a digital avatar for the object, while URN:NBNs require a landing page with accompanying metadata. (Please note that there are practically no use cases for this type of Persistent Identifier usage available.)
Position 8
Some Persistent Identifiers point to objects without metadata.
Answer
DataCite DOIs require mandatory metadata elements. URN:NBNs point to a landing page where you can publish or edit the metadata for an object. Handles do not require specific metadata. With all three systems, the Persistent Identifier can always direct to the metadata record of an object if required. (If you strongly agree with this statement, than this doubles your score in favour of Handles for this question, because Handle does not require specific metadata.)
Position 9
Persistent Identifiers point predominately to individual scanned objects.
Answer
With URN:NBNs the emphasis is on the sustainability of publication, data(sets) and accompanying metadata. A URN:NBN is therefore ideal to link to publications. DataCite DOIs, as the name suggests, generally point to data and datasets. Handles can be applied to individual objects (i.e files or scans). Handles are therefore most suited for individual scanned objects.
Position 10
Persistent Identifiers point predominantly to collections of objects i.e. books, artefacts, datasets.
Answer
With URN:NBNs the emphasis is on the sustainability of publication, data(sets) and accompanying metadata, but this makes URN:NBNs less suitable as a method of persistent identification for collections. DataCite DOIs and Handles are more suited for this purpose.
Position 11
The objects which have been assigned a persistent identifier can change, without changing the persistent identifier itself. Occasionally you might want to edit or improve the metadata, or change the content of an object, without creating a completely new version.
Answer
DataCite DOIs and URN:NBNs in principle require objects that stay the same. DataCite DOIs can change the content of a dataset, but with URN:NBNs a new identifier will be needed for the new version of the dataset. Handles have no such requirements. So if you want to create different versions of a dataset while using the same Persistent Identifiers, then Handles offer you this possibility, DataCite DOIs only partially and URN:NBNs do not offer this option at all.
Position 12
I find it important that the Persistent Identifier system requires specific metadata (e.g. who, what, when and where), so that the information is interoperable (within the Persistent Identifier system).
Answer
DataCite DOIs require specific metadata. URN:NBNs point to a landing page where you can publish your metadata and the National Library of the Netherlands expects you to provide this metadata. Handles do not require specific metadata. With all three systems the identifier can point to an object where the object itself is just a metadata record.
Position 13
My collections are extremely complex and are comprised of multiple items that Persistent Identifiers would need to navigate.
Answer
DataCite DOIs and URN:NBNs point preferably to publications and data(sets). However Handles are designed to work with both collections and individual objects.
THEME 3 Use: How will your organisation make use of Persistent Identifiers?
Position 14
It can be anticipated that objects and their accompanying Persistent Identifiers could be deleted.
Answer
If you want to be able to delete objects with Persistent Identifiers, you should be able to justify this decision. If you then still want to be able to delete your Persistent Identifiers yourself, then please consider if this is really what you want from this service. URN:NBNs do not offer an easy option for deleting Persistent Identifiers. The service provider must do this for you. With Handles, an administrator can delete your Persistent Identifiers. While with DataCite DOIs your Persistent Identifiers cannot be deleted completely, and will redirect to a landing page with explaining the type of object which was deleted.
Position 15
How much technical knowledge and time does your organisation have at its disposal to implement a Persistent Identifier System?
Answer
DataCite DOIs and URN:NBNs have (national) organisations which will provide this type of service. Handles have similar organisations, e.g. EPIC. You can also choose to implement and manage your own Handle server. However for this type of implementation you or your organisation will need to have the correct technical capabilities at your disposal.
Position 16
What would you pay for membership or subscription to a Persistent Identifier system exclusive of implementation and service costs?
Answer
DataCite currently has the highest fee, namely 750 euro per year for a prefix. Handles are 50 dollars for registration and then a yearly contribution of 50 dollars. While URN:NBN is a free persistent identifier service.” TE VERVANGEN DOOR “DataCite currently has the highest fee, namely 750 euro per year for a prefix. Handles are 50 dollars for registration and then a yearly contribution of 50 dollars. While URN:NBN is a free persistent identifier service. (Dutch archive/cultural heritage organisations can now use the Handle-based SURFsara PID service.)
THEME 4 Support: What do you expect from a Persistent Identifier Provider and their organisation?
Position 17
I find it important to have choice between different Persistent Identifier providers with my chosen type of Persistent Identifier system.
Answer
DataCite DOIs and URN:NBNs have national registration agencies. In the Netherlands this is Delft University of Technology and the National Library (Koninklijke Bibliotheek) respectively. With DataCite DOIs you can work together with an organisation that already has a prefix. Handles give you more freedom, but you also need to take this on for yourself and your organisation. If you are looking for a Handle provider you can choose from EPIC (European wide), SURFsara (Dutch based) or implement your own server.
Position 18
How much support do you expect from the Persistent Identifier provider when working with Persistent Identifiers in your organisation?
Answer
As the registration agency for DataCite DOIs, Delft University of Technology offers the most extensive support. The Dutch National Library offers limited support in their capacity as registration agency for URN:NBNs. In the case of Handles, you need to do most of the work yourself, however SURFsara and EPIC can offer some level of support.
Position 19
How much support do you expect from the Persistent Identifier providers when implementing necessary changes in your persistent identifiers, i.e. when you need to change the location of your object?
Answer
With Handles you organise this yourself, or arrange it via the Handle server of your EPIC client. With URN:NBNs you submit your changes through the metadata via your Registration Agency (the National Library of the Netherlands). While with DataCite DOIs you can make your changes in the metadata within the web interface from your registration agency, in this case Delft University of Technology.
Position 20
I find it important that there are relevant statistics about the use of my Persistent Identifiers available, e.g. how often they are resolved.
Answer
DataCite DOIs offer the most possibilities and works on providing citation statistics. Handles and URN:NBNs do not provide this as a standard service.
Position 21
Without changing the implemented Persistent Identifier system itself, I want to have the option to change to another Persistent Identifier provider.
Answer
Dutch DataCite DOIs are connected to DataCite Netherlands, which are provided through Delft University of Technology, or through one of their DataCite clients. Dutch URN:NBNs are taken care of through the National Library of the Netherlands only. Handles give you more options, as you can connect with (inter)national providers or implement and manage your own Handle server. Currently there is not really a fully developed solution for moving your Persistent Identifiers from one Persistent Identifier system (e.g. Handle) to another (e.g. URN:NBN).
THEME 5 Technical: What do you expect from the Persistent Identifier infrastructure (in terms of technical quality) and the technical basis of the resolution of identifiers?
Position 22
Resolution: The Persistent Identifier system needs to be scalable so that it is discoverable in a global context.
Answer
URN:NBNs have servers that resolve locally and nationally. DataCite DOIs and Handles use centralised global resolution.
Position 23
Actionable: All my Persistent Identifiers must point to an address online, or all my digital objects have a web address even if that object only consists of metadata (i.e. your Persistent Identifiers will never directly point to a physical object).
Answer
DataCite DOIs are, as the name suggests, ideal for directing to datasets. The presumption is therefore that the datasets can be accessed online. URN:NBNs can point to physical objects such as books, but it is expected that there will always be a landing page with information about said object available online. Handles can be actionable Persistent Identifiers, but they can also point to physical objects without a web address.
Position 24
Landing page: All my Persistent Identifiers always point first to a landing page rather than the object itself.
Answer
Both URN:NBNs and DataCite DOIs always direct to a landing page with information on the object, even if it is a physical object. Handles can point to an arbitrary location, such as a landing page, a digital object or a physical object.
Position 25
Part Identifiers: If I have assigned a Persistent Identifier to an object, I also want it to be possible to point to part of an object, e.g chapters in a book where the book has a Persistent Identifier, or to a distinct webpage on a given (archived) website, where the website has a Persistent Identifier, without having to create and assign a separate identifier.
Answer
Part identifiers are possible with Handles (@) and DataCite DOIs (#). URN:NBNs do not support this. However this type of part identifier is very rarely used in practical applications. Experts advise careful consideration of the organisation and granularity of your information and Persistent Identifiers. If it is important to you to e.g. point to chapters in a book, then instead of using a part identifier, you could also give each chapter a Persistent Identifier.