PROPOSED Web of Things Working Group Charter

The mission of the Web of Things Working Group is to counter the fragmentation of the IoT through the specification of building blocks that enable easy integration of IoT devices and services across IoT platforms and application domains. These building blocks should complement and enhance the use of existing standards, and allow WoT to be used within other ecosystems and communities. This reduces the initial friction for adoption and supports further industry adoption. This Working Group Charter covers those aspects that the Web of Things Interest Group (charter here) believes are mature enough to progress to W3C Recommendations.

Join the Web of Things Working Group.

This proposed charter is available on GitHub. Feel free to raise issues.

Charter Status	See the group status page and detailed change history.
Start date	1 June 2023 (ESTIMATED) (date of the "Call for Participation", when the charter is approved)
End date	1 June 2025 (ESTIMATED; Start date + 2 years)
Chairs	Sebastian Kaebisch (Siemens) and Michael McCool (Intel) (PROPOSED)
Team Contacts	Kazuyuki Ashimura (0.2 FTE)
Meeting Schedule	Teleconferences: Weekly with additional topic specific calls as appropriate. Face-to-face: We will meet during the W3C's annual Technical Plenary week; additional face-to-face meetings may be scheduled by consent of the participants, with no more than four (4) face-to-face meetings in total per year.

Motivation and Background

As a continuation of the work in the previous charter, this working group is tasked with the standardization or extension of the building blocks identified by the use cases resulting from the work of the Web of Things Interest Group (IG) as being important to advance the Web of Things. The WoT building blocks are intended to complement and integrate to existing and emerging IoT standards using Web technologies. As a result, the building blocks focus on enabling cross-platform and cross-domain interoperability in the IoT.

Scope

During this charter, the Working Group would work on the following:

Update Existing Specifications:: The WG will add new features and address issues discovered during implementation of already published specifications. Unlike the last charter, these would not be limited to backward-compatible updates.
Support WoT Interoperability:: The WG will improve out-of-the-box interoperability and enable the integration of WoT into other ecosystems and communities. Thus, the WG will define core binding and profiling mechanisms, specify additional protocol and payload bindings, and define appropriate profiles.
Improve Management of TDs:: Additional mechanisms around for the management of TDs are needed to improve workflows that use them. Thus, the WG will update the Discovery specification with additional features, including geolocation. In other specifications, the WG intends to add a mechanism to sign TDs, define how to manage versions of TDs and define how to parse, validate, consume and lint TDs.
Increase Descriptiveness of TDs:: The WG will work on increasing the descriptive power of TDs to allow using them in more use cases. This includes describing dynamic resources, historical values (timeseries), repeating payloads, both static and dynamic geolocation information, manageable actions and more precise definitions of data schemas for each type of operation.
Improve Security and Privacy:: Define reusable external security vocabularies, simplify the use of security schemes, and other work as appropriate.
Support New Use Cases:: Address the functional requirements of new use cases, such as Digital Twins.

Details for planned work items, which however are subject to change, are available in a separate document.

Out of Scope

The following features are out of scope, and will not be addressed by this Working group.

Application- and domain-specific metadata vocabularies:: The Working Group is restricted to work on cross-domain vocabularies.
APIs and security frameworks specific to particular platforms external to the W3C:: The scope of the Working Group is restricted to APIs and security frameworks that are applicable across platforms. We will not define new security mechanisms but will use existing mechanisms and best practices.
Modification of protocols:: If during work on protocol bindings, it becomes apparent that changes are needed to protocols, the Web of Things Working Group will rely on the organization responsible for the protocol to make the changes. It is out of scope for the Working Group to standardize such changes itself.

Deliverables

Updated document status is available on the group publication status page. The specification names given below are not exact titles as we are currently discussing how to best manage versioning and how to reflect this in the title of documents. Final titles will include "Web of Things".

Normative Specifications

The Working Group will deliver the following W3C normative specifications:

Architecture (Update)

This specification defines the Web of Things architecture, terminology, fundamental concepts, architecture and deployment patterns, and horizontal security and privacy requirements. It introduces and gives an overview of the family of WoT building block specifications described below.

Draft state:No draft

Expected completion:1 June 2025

Adopted Draft: This will be an update of the current Web of Things (WoT) Architecture specification published at https://www.w3.org/TR/wot-architecture11/, as a Candidate Recommendation on 19 January 2023.

Discovery (Update)

This specification defines a Discovery process for WoT, and would be a backward-compatible update to the existing WoT Discovery Specification.

Draft state:No draft

Expected completion:1 June 2025

Adopted Draft: This will be a revision of the current Web of Things (WoT) Discovery specification published at https://www.w3.org/TR/wot-discovery/, as a Candidate Recommendation on 19 January 2023.

Thing Description (Update)

This specification defines the Web of Things Thing Description information model and its JSON-LD serialization. This deliverable will add new features and address issues discovered during implementation.

Draft state:No draft

Expected completion:1 June 2025

Adopted Draft: This will be a further iteration of the current Web of Things (WoT) Thing Description specification published at https://www.w3.org/TR/wot-thing-description11/, as a Candidate Recommendation on 19 January 2023.

Profile

This specification defines a profiling mechanism to enable out-of-the-box interoperability between Things and Consumers which conform to a prescriptive set of constraints, and defines at least a first basic HTTP-based profile.

Draft state: Working Draft

Expected completion:1 November 2023

Profile (Update)

This specification is an update to the WoT Profile specification, with additional normative profiles as appropriate.

Draft state: No draft

Expected completion:1 June 2025

Other Deliverables

Other non-normative documents may be created including:

Use Cases and Requirements;
Security and Privacy Guidelines (to be published as a W3C Note);
Test suite and implementation reports for each specification;
Primer or Best Practice documents to support web developers when designing applications.
WoT Scripting API (W3C Note): This document will present a design for a Scripting API that will support exposing and consuming Thing Descriptions while providing a high-level interface to interactions that is independent of protocol. The work will continuously align with the WoT TD specification. Besides these efforts, alignment with the WoT Discovery specification will be the main topic.
Draft state: Group Note
Binding Documents for Specific Protocol, Payload and Ecosystems (W3C Notes): These documents will take the requirements specified in Web of Things (WoT) Binding Templates and specify how protocols and payload formats should be used to allow integration of specific classes of IoT systems and ecosystems.

Timeline

June 2023: First teleconference
July 2023: First face-to-face meeting
September 2023: Requirements and Use Cases for WoT Discovery 1.1
January 2024: FPWD for WoT Discovery 1.1
August 2024: CR Transition for WoT Discovery 1.1
August 2024: Updated publication of WoT Security and Privacy Guidelines as a Note
December 2024: PR Transition for WoT Discovery 1.1
March 2025: REC Transition for WoT Discovery 1.1

Success Criteria

In order to advance to Proposed Recommendation, each normative specification is expected to have at least two independent interoperable implementations of every feature defined in the specification, where interoperability can be verified by passing open test suites, and two or more implementations interoperating with each other. In order to advance to Proposed Recommendation, each normative specification must have an open test suite of every feature defined in the specification.

A testing plan will be developed for each specification, starting from the earliest drafts.

To promote interoperability, all changes made to specifications in Candidate Recommendation or to features that have deployed implementations should have tests.

Each specification should contain sections detailing all known security and privacy implications for implementers, Web authors, and end users.

Coordination

For all specifications, this Working Group will seek horizontal review for accessibility, internationalization, privacy, and security with the relevant Working and Interest Groups, and with the TAG. Invitation for review must be issued during each major standards-track document transition, including FPWD. The Working Group is encouraged to engage collaboratively with the horizontal review groups throughout development of each specification. The Working Group is advised to seek a review at least 3 months before first entering CR and is encouraged to proactively notify the horizontal review groups when major changes occur in a specification following a review.

Additional technical coordination with the following Groups will be made, per the W3C Process Document:

In addition to the above catch-all reference to horizontal review which includes accessibility review, please check with chairs and staff contacts of the Accessible Platform Architectures Working Group to determine if an additional liaison statement with more specific information about concrete review issues is needed in the list below.

W3C Groups

Web of Things Community Group: For collaboration on community outreach to increase adoption, implementation, and understanding, as well as collecting feedback from the global community. Meetings held in English.
Web of Things Japanese Community Group: For collaboration on community outreach to increase adoption, implementation, and understanding, as well as collecting feedback from the Japanese community. Meetings held in Japanese.
Web of Things Interest Group: For collaboration as outlined in Scope.
JSON-LD Working Group: For collaboration on JSON-LD features and WoT use cases.
Efficient Extensible Interchange Community Group: In relation to efficient interchange for Thing Descriptions.
Web and Automotive Business & Working Groups: For collaboration on technologies and requirements relating to connected cars and the Web of Things.
Device and Sensors Working Group: For coordination on APIs for sensors and actuators.
Decentralized Identifier Working Group: For coordination on identity management and information lifecycle.
Web & Networks Interest Group: For collaboration on networking and computing technologies on the edge and in the cloud when exposing interactions between Things.
Spatial Data on the Web Working Group: For collaboration on geolocation, in conjunction with the Open Geospatial Consortium.
Accessible Platform Architectures Working Group: In addition to horizontal review, coordination on impact of WoT technologies on accessibility, and support for new capabilities that help leverage WoT connectivity and sensor networks for accessibility support in public and private spaces is needed.
Privacy Interest Group: In addition to horizontal review, during development of deliverables such as discovery and information lifecycle that require the development of a privacy-preserving architecture, close technical collaboration with the Privacy Interest Group will be needed.
Schema Extensions for IoT Community Group: For collaboration on extensions to Schema.org for IoT use cases.

External Organizations

To succeed in establishing inter-platform standards, W3C needs to coordinate with IoT alliances and standards development organizations. A longer list is available on the Interest Group wiki that includes cooperations partners from former Web of Things charters.

List of active and new liaisons:

OPC Foundation: For coordination on the development of the OPC UA Binding for the W3C Web of Things. A formal agreement between the OPC Foundation and the W3C is being considered to establish an official relationship.
ECHONET Consortium: For collaboration on integrating ECHONET Consortium based platforms within the Web of Things, including platform metadata and approaches for enabling semantic interoperability, and end to end security across platforms.
Industrial Digital Twin Association: For coordination on the use of TDs and Binding Templates in the Asset Interface Description (AID) submodel for the Asset Administration (AAS) specification. Additionally, the AAS submodels can be used for Digital Nameplate (DNP) and Product Carbon Footprint (PCF) to form the Digital Product Passport (DPP) of products that the European Commission is demanding each product to supply (DPP4.0). Also see the related GitHub comment.
ASHRAE: For coordination on the development of the BACnet (ASHRAE 135-2020) Binding for the W3C Web of Things .
IETF: Coordinate common interests related to Internet of Things and Web of Things, e.g., issues such as serialization, security, and trustworthiness.
IRTF Thing to Thing Research Group: For coordination of matters of mutual interest in relation to the Web of Things, such as data modelling, discovery, directory services, and IoT semantics.

Connectivity Standards Alliance (CSA)

To coordinate smart home use cases and to develop a potential Matter Protocol Binding.

One Data Model

For coordination of Semantic Definition Format (SDF) with the Thing Description.

Open Geospatial Consortium (OGC)

To coordinate geolocation use cases and potential geo-based definitions for Thing Models and Thing Descriptions.

Conexxus

To coordinate retail use cases and show case in PlugFests.

ECLASS

For collaboration and coordination of the technical realization of the use of ECLASS in the W3C Thing Description.

ITU-T

Coordinating smart city and digital twin use cases and aligning terminology definitions.

Participation

To be successful, this Working Group is expected to have 6 or more active participants for its duration, including representatives from the key implementors of this specification, and active Editors and Test Leads for each specification. The Chairs, specification Editors, and Test Leads are expected to contribute half of a working day per week towards the Working Group. There is no minimum requirement for other Participants.

The group encourages questions, comments and issues on its public mailing lists and document repositories, as described in Communication.

The group also welcomes non-Members to contribute technical submissions for consideration upon their agreement to the terms of the W3C Patent Policy.

Participants in the group are required (by the W3C Process) to follow the W3C Code of Ethics and Professional Conduct.

Communication

Technical discussions for this Working Group are conducted in public: the meeting minutes from teleconference and face-to-face meetings will be archived for public review, and technical discussions and issue tracking will be conducted in a manner that can be both read and written to by the general public. Working Drafts and Editor's Drafts of specifications will be developed in public repositories and may permit direct public contribution requests. The meetings themselves are not open to public participation, however.

Information about the group (including details about deliverables, issues, actions, status, participants, and meetings) will be available from the Web of Things (WoT) Working Group home page.

Most Web of Things (WoT) Working Group teleconferences will focus on discussion of particular specifications, and will be conducted on an as-needed basis. However, one teleconference will be held weekly to coordinate activities among the task forces responsible for each specification.

This group primarily conducts its technical work on GitHub issues, using a main repository for general topics and more specific repositories for individual specifications. The public is invited to review, discuss and contribute to this work.

The group may use a Member-confidential mailing list for administrative purposes and, at the discretion of the Chairs and members of the group, for member-only discussions in special cases when a participant requests such a discussion.

Decision Policy

This group will seek to make decisions through consensus and due process, per the W3C Process Document (section 5.2.1, Consensus). Typically, an editor or other participant makes an initial proposal, which is then refined in discussion with members of the group and other reviewers, and consensus emerges with little formal voting being required.

However, if a decision is necessary for timely progress and consensus is not achieved after careful consideration of the range of views presented, the Chairs may call for a group vote and record a decision along with any objections.

To afford asynchronous decisions and organizational deliberation, any resolution (including publication decisions) taken in a face-to-face meeting or teleconference will be considered provisional. A call for consensus (CfC) will be issued for all resolutions (for example, via email, GitHub issue or web-based survey), with a response period from one week to 10 working days, depending on the chair's evaluation of the group consensus on the issue. If no objections are raised by the end of the response period, the resolution will be considered to have consensus as a resolution of the Working Group.

All decisions made by the group should be considered resolved unless and until new information becomes available or unless reopened at the discretion of the Chairs or the Director.

This charter is written in accordance with the W3C Process Document (Section 5.2.3, Deciding by Vote) and includes no voting procedures beyond what the Process Document requires.

Patent Policy

This Working Group operates under the W3C Patent Policy (Version of 15 September 2020). To promote the widest adoption of Web standards, W3C seeks to issue Web specifications that can be implemented, according to this policy, on a Royalty-Free basis. For more information about disclosure obligations for this group, please see the licensing information.

Licensing

This Working Group will use the W3C Software and Document license for all its deliverables.

About this Charter

This charter has been created according to section 3.4 of the Process Document. In the event of a conflict between this document or the provisions of any charter and the W3C Process, the W3C Process shall take precedence.

Change log

Changes to this document are documented in this section.