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user identifier

vr.tr.user-identifier · thing-q818371

Let an agent explain numeric Unix-like user identifiers, relay UID conventions and reserved ranges from public documentation, describe their roles in access control, ownership and auditing, and relay privacy considerations.

Thing Registry Cross-cutting context XCT.QTY
Bundle → Layer → Finding → QuestionsClassifiersWhat it isWhy it existsDistinguishing featuresWhat robots and AI may and may not doMoral aspectsOwnersLinks to other meta-modelsIdentity and identifiersDirect propertiesRecognitionCapabilities and actionsHazards and failure modesStandards and interfacesContext of useSources

Bundle → Layer → Finding → Questions Filled

4 bundles · 8 layers · 8 findings · 16 questions

Understand What a user identifier is.

Definition

Definition.

Definition

Definition.

  1. What is a user identifier, and what forms does it take? definition
  2. Is the question about a user ID, a username, a session ID or a device ID? boundary

Unix

Unix UIDs.

Unix

Unix.

  1. How do Unix UIDs work, including root, system ranges and mapping to names? definition
  2. Which entry fits Unix user management? action
Use Uses.

Access

Access control.

Access

Access.

  1. How are user IDs used for permissions, ownership and auditing? provenance
  2. Which references are standard? provenance

Data

Data linking.

Data

Data.

  1. How do applications use user IDs as keys, and how are federated identifiers handled? provenance
  2. Which entry fits OpenID Connect? action
Protect Privacy and security.

Privacy

Privacy.

Privacy

Privacy.

  1. When are user identifiers personal data, and how should they be protected? provenance
  2. Which sources are cited? provenance

Security

Security.

Security

Security.

  1. What security issues arise from predictable or exposed user IDs, in general terms? provenance
  2. Which entry fits identity and access management? action
Context History and design.

History

History.

History

History.

  1. How did user identifiers develop with multi-user operating systems? provenance
  2. Which entry fits the history of Unix? action

Design

Design choices.

Design

Design.

  1. What are the trade-offs between sequential, random and opaque identifiers? provenance
  2. Which entry fits identifier design? action

Classifiers Filled

Family
Thing Registry
Category
Cross-cutting context
Entry kind
thing
Plane
XCT
Domain
XCT.QTY

What it is Filled

A non-negative integer used in Unix-like operating systems to identify a user account within the relevant system or identity namespace; a user identifier, or UID, supports access control, file and process ownership, and auditing, and its handling raises privacy and security considerations.

Why it exists Filled

Let an agent explain numeric Unix-like user identifiers, relay UID conventions and reserved ranges from public documentation, describe their roles in access control, ownership and auditing, and relay privacy considerations.

Distinguishing features Filled

  • Uniqueness within a system
  • Non-negative integer form
  • Access control role
  • Privacy sensitivity

What robots and AI may and may not do Filled

Must not

  • Change a user identifier to gain or grant privileges without authorization.
  • Link identifiers across systems to track a person without consent or legal basis.
  • Expose user identifiers in public logs or URLs where they help attackers.
  • Reassign an identifier in a way that hands one user's files or data to another.

Only with a human decision

  • Deleting, merging or reassigning user accounts and their identifiers requires human involvement.

May

  • Use Unix-like UIDs to enforce access control in systems the agent administers.
  • Check that UIDs are unique and not reused for different accounts without review.
  • Explain how numeric UIDs work in Unix-like operating systems.

Moral aspects Filled

  • Identifiers tie actions and data to people, so they are personal data and a privacy risk when linked.
  • Mistakes in identifiers can give the wrong person access to private data.

Who is affected

  • Account holders
  • System administrators
  • People whose data a system holds

Owners Filled

Steward

The operator of the system that issues it.

Links to other meta-models Filled

parent

  • Q28920052 - registry parent class
  • Q6545185 - registry parent class

related

  • non-negative integer - in registry terms
  • unique identifier - in registry terms
  • user account - in a system
  • access control - and ownership

What else AI and robots need to interact with it Filled

Identity and identifiers required Filled

  • Vercy registry: vr.tr.user-identifier
  • Wikidata: Q818371 (https://www.wikidata.org/wiki/Q818371)
  • POSIX: uid_t user ID type

Direct properties not applicable Not applicable

  • Unix root UID: 0 value
  • typical regular user UID start: 1000 value - many Linux distributions
  • UID range: 0 to 4294967295 values - 32-bit

Plane XCT: no invented physical properties.

Recognition optional Filled

  • A UID is a numeric account identifier in a Unix-like operating system.
  • It can identify a human user's account or a service account within the relevant system or identity namespace.
  • Usernames are human-readable names, session IDs identify sessions, and device IDs identify hardware.
  • Not a visible object; a number or string in system records.

Capabilities and actions required Filled

  • explain forms and conventions
  • relay Unix UID rules
  • describe uses
  • relay privacy considerations

Hazards and failure modes required Filled

  • UID collisions across systems
  • Exposure of identifiers enabling tracking
  • Confusing identifiers with usernames

Standards and interfaces required Filled

  • POSIX specifications for user IDs
  • Data protection laws treating identifiers as personal data
  • Identity standards such as OpenID Connect

Context of use required Filled

  • Uniquely identifying a user in a system.
  • Unix and Linux UIDs including root and system ranges
  • Windows security identifiers as an analogue
  • database and application user IDs
  • web service account identifiers
  • federated identifiers such as OpenID subject identifiers

Sources Filled

  1. Wikidata item Q818371: user identifier - identity and sense of the item
  2. Wikipedia: User identifier - general description of the item

Open questions

  • Should Unix UID be a separate entry?
  • How should POSIX and identity standards be linked?
  • How should privacy guidance be linked?

Machine files

Card as JSON Specification Card backlog vercy.card/1

Provenance

thing registry research (pass 2) · unreviewed

Built from: models/things/publications/thing-q818371/spec.json