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About ARKs

Did you know…

… that ARK is a PID (Persistent IDentifier), along with DOI, ORCID, and ROR?
… that ARK may be the fastest growing PID scheme you’ve never heard of?
… that an average of 5 new ARK organizations are registered every week?
… that the ARK scheme is more than 25 years old?
… that no one has to pay for the right to create ARKs?
… that there are over 15.3 billion ARKs in the world?
… that ARK organizations include universities, journals, national libraries, national and regional archives, and fine art and natural history museums?

Archival Resource Key (ARK) identifiers are URLs that support long-term access to information. Learn below what you need to know about ARKs, whether you’re planning how your system or collection will use them, or you’re a developer building ARK tools.

ARK Anatomy

    https://example.org/ark:12345/x54xz321/s3/f8.05v.tiff 
    \_________________/ \__/\___/ \______/\____/\_______/ 
               |         |    |      |      |       | 
               |   ARK Label  |      | Sub-parts  Variants 
               |              |      | 
 Name Mapping Authority (NMA) |    Assigned Name 
                              |
               Name Assigning Authority Number (NAAN)

A peek at ARK anatomy. You can spot an ARK by its internal ark: label.

Frequently Asked Questions (FAQs)

ARK FAQs in English, French, and Spanish

Recommended for all users

ARK overview

What ARKs are and why you would use them
Identifiers and persistent identifiers (PIDs)
Resolvers
ARK structure
How people are using ARKs
Persistence means persistent management
ARK Community Code of Conduct

Why ARKs?

By 2001 there were 4 major PID types – this is why a 5th was needed.

ARK NAANs and systems

Name Assigning Authority Number (NAAN) registry
Nice Opaque Identifier (Noid) systems
N2T: a global resolver
Resolver feature: suffix passthrough

ARK features

Shoulders (local namespaces)
Metadata
Inflections: metadata and policy statement
Deleting ARKS

Comparing ARKs, DOIs and other identifier systems

Reasons to use ARKs as compared to DOIs
What ARK, DOI, Handle, PURL, and URN have in common
How ARKs differ from identifiers like DOIs, Handles, PURLs, and URNs
Using multiple identifier systems
When to use ARKs compared to DOIs, Handles, PURLs, or URNs

Getting started: what to plan for as you implement ARKs

Get a Name Assigning Authority Number (NAAN)
Decide what ARK features you need
Choose (or build) an ARK system

Recommended for developers

The following in-depth information will be useful if you’re extending your own local repository or system with Noid software to support ARKs, or if you’re developing an ARK system.

General identifier concepts and conventions

Terminology
NAANs, prefixes, bases, and suffixes
Shoulder practices
Name Mapping Authority (NMA) services
Resolution, N2T, Opacity, Test identifier conventions
Base identifier extensions
The “NCDA” check character convention

Running minters and resolvers

Minting ARK name strings
Best practices for minting ARK name strings
Opaque identifiers
Making server content addressable with ARKs
ARK citation format
ARK inflection vs. content negotiation

More about the N2T global resolver

How N2T works
N2T is not just for ARKs

ARK namespaces and sub-namespaces

ARK namespace overview
ARK shoulder as namespace
Shared NAANs
The NAAN’s role in N2T ARK resolution
How to make changes to a NAAN

More about ARK shoulders

Shoulder format
Implementing shoulders

Testing ARKs with N2T

Test with your own NAAN
Request a shoulder under a shared NAAN

ARK implementation best practices

ARK creation and object lifecycle
Metadata
Policy statements