Some Strawman Amendments to the Identifier WD

• Part A
• Part B
• Part C
• Part D

Part A. Establishing AuthorityID Ownership and Resolving ResourceIDs

Overview:

This proposed amendment attempts to clarify how identifiers are created as described in the Identifiers WD, section 3.3 and Appendix B. The main additions are:

• A request for an AuthorityID is handled through a publishing registry to global registry. The request is accompanied by the identifier of the publishing registry to be saved in the global registry as the "registry of origin" for that authority ID.

• Registries are registered as first-class resources. Their descriptions should include the AuthorityIDs that they have resources for.

Detailed Description:

Authority IDs are owned by organizations; they are ultimately responsible for the creation of unique resource keys within the namespace established by the authority ID. Ownership of an authority ID is claimed via registration with a global IVOA Name-granting registry, a registry service that is capable of ensuring unique ownership by a publishing registry on behalf of an organization. (The Name-granting registry and the publishing registry may be one and the same.)

Once an authority ID is registered, a global registry can resolve the authority ID to a registered description of the organization that owns it.

How an organization requests to take ownership of an authorityID depends on whether the organization is already registered:

• If the organization is not registered, the request must be accompanied by a valid metadata description using IVOA Resource metadata. If the requested authority ID is not in use, then the organization will be globally registered along with its ownership of the authority ID. The resource ID for the organization may use the requested authority ID.

• If the organization is not registered, the request must be accompanied by a registered resource ID for the organization. To approve the request, the Name-granting registry must be able to resolve the resource ID to an organization.

The request must also be accompanied by the Resource ID for the publishing registry submitting the request, refered to as the registry of origin. This registry shall be considered the most likely location to contain a description of a resource having the requested authority ID. It should also be considered the most authoritative source of descriptions with that authority ID.

Registries must be registered as first-class resources. The Registry metadata should include the authorityIDs that it contains records for.

The following represents a minimum recipe for a registry to resolve a resource identifier. Certain registry implementations may support additional shortcuts (some which may be standardized in the future); however, this minimum recipe should always work.

1. Any publishing or searchable registry can be queried to resolve a resource identifier.
2. If the initial registry cannot resolve the ID, the query can be given to a global registry.
3. If the global registry cannot resolve it, the global Name-granting registry can be queried with the resource identifier's authority ID to get back its registry of origin as well as a list of registries containing resources matching the authority IDs.
4. The registry of origin is queried with the resource ID.
5. If the ID is still unresolved, each of the other registries returned in (3) can be searched in turn.
6. If the ID is still unresolved, then any registry known to the system may be searched.