Read the descriptor’s fields and scopes
03JavaScript Object Notation (JSON) represents named values, arrays and objects. A JRD describes a subject and may contain aliases, subject properties and typed links. Applications interpret their vocabulary; finding a link does not automatically fetch or trust it.
The author link has titles en: About Carol and und: Carol, plus a link-scoped role=writer. That does not replace subject-scoped role=editor. Rules explain duplicate-language recovery and repeated-relation preference.
Source for this drawing: RFC 7033 · Read RFC section 4.4 ↗
New to this? Start hereA quick picture + helpful background
A message needs an address.
Think of a packet as a small addressed envelope. Devices pass it onward; transport protocols decide what delivery promises an application gets.
Helpful first, if these ideas are unfamiliar
These pictures are analogies to help you learn. The linked RFC explains the actual rules.
Terms in this drawing
Related RFCs and changes
“Updates” changes part of an earlier RFC. “Obsoletes” replaces it. This list shows selected related documents.
Optional fields stay optional, and link properties belong to their link.
- The subject URI SHOULD be present and MAY differ from resource, for example after canonicalization or a move. aliases is an OPTIONAL array of URIs identifying the same entity. A different subject does not by itself authenticate an account transfer.
- Subject properties are OPTIONAL, with URI keys and string or null values. Link properties have the same value types but a different scope. Clients MUST ignore unknown JRD members without treating their presence as an error.
- links is OPTIONAL. Every link MUST have exactly one rel value: a registered relation name or an absolute URI. href, type, titles and properties are OPTIONAL. Omitted href is not intrinsically malformed. type hints at a media type; it is not proof about a retrieved representation.
- Titles use language tags or und for an undetermined language, with human-readable strings. A JRD SHOULD NOT repeat a language tag within a link, but clients MUST NOT treat repetition as an error and MAY choose the titles they use. Link ordering MAY convey preference for repeated relations.
- URI relation values use simple string comparison under RFC 3986 §6.2.1, without URI normalization. Registered relation names compare case-insensitively under the RFC’s normative Web Linking reference, RFC 5988 §4.1.
Pictures show selected fields, not literal complete JSON serialization. Ellipses abbreviate illustrative http://example.com/ns/ property keys. Production applications must define and register properties (§8.6); the guide defines no production vocabulary.
Read the RFC section ↗