When a resolution request comes in from the general public, N2T looks up the identifier and redirects the original link to a forwarding link. To do this it uses two different resolution “patterns”. To begin, N2T tries to resolve according to information found in an individual stored identifier. Failing that, N2T tries to resolve according to any stored class rules, based on the identifier type.
N2T has a different kind of stored data for each pattern. First, it stores individual records for about 50 million object identifiers (eg, ARKs, DOIs) that it obtains from three sources: EZID.cdlib.org, Internet Archive, and YAMZ.net. When such records include a redirection URL (target) and descriptive metadata, N2T can act on inflections as well as perform suffix passthrough and “content negotiation”. To support creation and maintenance of individual identifier records, there is an N2T API requiring login credentials. The API also allows batch operations and unique identifier generation (minting).
Second, even if N2T knows nothing about an individual identifier, resolution may still work because of a stored routing rule record triggered by the type of the identifier. N2T maintains over 3500 rule records regularly updated from several sources, including the NAAN registry, a database of shoulders (see namespaces), and a formal partnership on compact identifiers with identifiers.org.
When demand for a global ARK resolver arose, basic principles of openness and generality prevented the designers from creating yet another silo in the DOI/Handle/PURL mold. Instead, the ARK resolver was built to be a generic, scheme-agnostic resolver called N2T (Name-to-Thing), which now resolves over 900 types of identifier, including ARKs, DOIs, Handles, PURLs, URNs, ORCIDs, ISSNs, etc. Resolution is essentially looking in a table for an identifier string, regardless of type, and redirecting it to the right place.
The same basic principles guided the design of Noid, which was built for ARKs but is also regularly used by organizations that mint Handles.