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Status update for WG

In a 2018 event about IoT futures hosted by ZigBee, by far the most frequently cited challenge was the inconsistency and lack of interoperability across the field of IoT data models; specifically the lack of a common data model.

Based on this observation, One Data Model (OneDM) was started in early 2019, bringing several IoT SDOs (Standards Development Organizations) and IoT device and platform vendors together under a broad, multi-party liaison agreement.

The goal of OneDM is to arrive at a common set of data and interaction models that describe IoT devices. This will enable an application to work with IoT devices from different ecosystems, without a need for converting data and interactions from the model of one organization to that of the other. Ideally, for every class of IoT device, there is just a single model selected/created by the participating organisations, which everyone can adopt.

The first step towards this goal was to have a common way how to write down a model. Since all participating organizations are currently doing this in their own ways, it made sense to develop a single way to describe models. Over a little more than a year, the Semantic Definition Format (SDF) was created, which can represent IoT Things, their composition from reusable Objects, their Interaction Affordances (Properties, Actions, Events), and the data models relevant to describe these Affordances. SDF is representing these models in JSON. This allows re-use of specification formats such as CDDL (RFC8610) and the formats proposed at for both the description of the SDF format itself and the structure of the data to be modelled in SDF. Abundant tools and libraries are available to produce/consume JSON, so tooling to work with SDF models can be created efficiently.

Some 200 models in SDF format have been contributed by participating ecosystems; new models are being submitted continually. Version 1.0 of the SDF specification was published on the OneDM github repository and as an Internet-Draft. OneDM is now focusing on consolidating the body of submitted models and developing processes for arriving at harmonized models that span different industry ecosystems in a common way.

Further development is needed on SDF, both with respect to functionality and editorial quality. OneDM is looking towards IETF as the standards development organization that is both providing the technical quality sought after and fits into the open collaboration model of OneDM itself.

The objective of the ASDF WG will be to work with OneDM and its contributing organizations and develop SDF to an IETF-quality specification.

In the process, some smaller pieces may become usable independently from SDF itself and its applications. JSON Path (similar to, but different in scope from JSON Pointer documented in RFC6901) might be an example for such a spin-off specification -- it is currently defined on a website and would benefit from a more formal definition so it can be used in discovery processes involving SDF models.

Status: non-WG Forming
Responsible AD: TBD
BoF proponents: Michael Koster <​>, Carsten Bormann <​>
BoF chairs: Michael Richardson, Niklas Widell
Number of people expected to attend: 50
Length of session (1, 1.5, 2, or 2.5 hours): 100 minutes
Conflicts to avoid (whole Areas and/or WGs): CORE, CBOR, COSE [fill in!]

Brief introduction into OneDM, SDF (Proponents)
Views of contributing ecosystems (e.g., OCF, OMA LwM2M, ...)
Calling the questions

Links to the mailing list, draft charter if any, relevant Internet-Drafts, etc.
Mailing List:
Draft charter: ​
Relevant drafts:
Use Cases: (no draft, see ​ and ​ for info)
Solutions: ​