Semantic Definition Format (SDF)

Created

  • 2025-03-27

Last Updated

  • 2026-05-12

Available Formats

SDF Quality Names

Registration Procedure(s)

  • Specification Required

Expert(s)

  • Ari Keranen (primary), Michael Koster (backup)

Reference

  • RFC 9880: Semantic Definition Format (SDF) for Data and Interactions of Things

Available Formats

Name Brief Description Reference Change Controller
$comment source code comments only, no semantics RFC 9880 IETF
const constant value RFC 9880 IETF
contentFormat content format RFC 9880 IETF
default default value RFC 9880 IETF
description long description text RFC 9880 IETF
enum sdfChoice limited to text strings RFC 9880 IETF
exclusiveMaximum exclusive maximum for a number RFC 9880 IETF
exclusiveMinimum exclusive minimum for a number RFC 9880 IETF
format specific format for a text string RFC 9880 IETF
items items of an array RFC 9880 IETF
label short text (no constraints); defaults to key RFC 9880 IETF
maxItems maximum number of items in an array RFC 9880 IETF
maxLength maximum length for a text string (in characters, i.e., Unicode scalar values) RFC 9880 IETF
maximum maximum for a number RFC 9880 IETF
minItems minimum number of items in an array RFC 9880 IETF
minLength minimum length for a text string (in characters, i.e., Unicode scalar values) RFC 9880 IETF
minimum minimum for a number RFC 9880 IETF
multipleOf step size of number RFC 9880 IETF
nullable boolean: can the item be left out? RFC 9880 IETF
observable boolean: can the item be observed? RFC 9880 IETF
pattern regular expression pattern for a text string RFC 9880 IETF
properties named dataqualities for type="object" RFC 9880 IETF
readable boolean: can the item be read? RFC 9880 IETF
required which data items are required? RFC 9880 IETF
sdfChoice named dataqualities for a choice RFC 9880 IETF
sdfData named dataqualities for an independent data type definition RFC 9880 IETF
sdfInputData input data to an action RFC 9880 IETF
sdfOutputData output data of an action or event (sdfRequired applies here) RFC 9880 IETF
sdfRef sdf-pointer to definition being referenced RFC 9880 IETF
sdfRequired pointer-list to declarations of required components RFC 9880 IETF
sdfRequiredInputData pointer-list to declarations of required input data for an action RFC 9880 IETF
sdfType more detailed information about the type of a string RFC 9880 IETF
type general category of data type RFC 9880 IETF
uniqueItems boolean: do the items of the array need to be all different? RFC 9880 IETF
unit engineering unit and scale (per SenML registry) RFC 9880 IETF
writable boolean: can the item be written to? RFC 9880 IETF

SDF Quality Name Prefixes

Registration Procedure(s)

  • Expert Review

Expert(s)

  • Ari Keranen (primary), Michael Koster (backup)

Reference

  • RFC 9880: Semantic Definition Format (SDF) for Data and Interactions of Things

Available Formats

Prefix Contact Reference
oma Open Mobile Alliance (OMA) https://www.openmobilealliance.org/specifications/registries/sdfqualitynames

sdfType Values

Registration Procedure(s)

  • Specification Required

Expert(s)

  • Ari Keranen (primary), Michael Koster (backup)

Reference

  • RFC 9880: Semantic Definition Format (SDF) for Data and Interactions of Things

Available Formats

Name Description type JSON Representation Reference Change Controller
byte-string A sequence of zero or more bytes string base64url without padding RFC 8949, Section 3.4.5.2 IETF
unix-time A point in civil time [1] number POSIX time RFC 8949, Section 3.4.2 IETF

SDF Feature Names

Registration Procedure(s)

  • Specification Required

Expert(s)

  • Ari Keranen (primary), Michael Koster (backup)

Reference

  • RFC 9880: Semantic Definition Format (SDF) for Data and Interactions of Things
Name Brief Description Reference Change Controller
No registrations at this time.

Contact Information

Name Contact URI Last Updated
Open Mobile Alliance (OMA) helpdesk&omarg.org 2026-05-12

Footnote

[1]

Note that the definition of unix-time does not imply the capability to represent points in time that fall on leap seconds. More date/time-related sdfTypes are likely to be added in the sdfType value registry.