subjectUniqueID

subjectUniqueID is a persistent, system-wide unique identifier assigned to a subject within a data management or identity framework. It serves as an unambiguous reference to a person, device, or entity across applications and processes.

Typically opaque and non-reversible, the subjectUniqueID is designed to remain stable over time, even as attributes such as names or contact details change. It is distinct from natural identifiers and is often used as the primary key to link records across databases.

Common characteristics include global or domain-wide uniqueness, persistence, and a binding relation to subject attributes through separate mappings. Implementations frequently rely on UUIDs or GUIDs, numeric sequences, or namespace-based identifiers, and may be generated deterministically or randomly depending on the system.

Use cases include identity management, data governance, auditing, and access control. In federated or multi-application environments, a single subjectUniqueID lets disparate systems reference the same subject without exposing sensitive attributes in identifiers.

Privacy and security considerations emphasize using opaque identifiers, limiting exposure of mapping tables, and enforcing access controls. Pseudonymization and encryption at rest or in transit help reduce privacy risks; policy governance determines lifecycle, deprecation, and migration of IDs.

Interoperability notes: some standards treat the subject identifier as a sub claim in OpenID Connect or as an identifier in SCIM or SAML profiles, but subjectUniqueID is implementation-specific and may be decoupled from presentation identifiers such as usernames.

Lifecycle and governance cover creation triggers, versioning, deprecation plans, and clear procedures for migrating references during schema changes or data consolidation.

See also: UUID, GUID, identity management, data governance, privacy-preserving identifiers.