PROPOSED Web of Things Interest Group Charter

The mission of the Web of Things Interest Group is to support the efforts of the Web of Things Working Group by identifying appropriate standardization targets through engagement with stakeholders inside and outside the W3C and through collection and analysis of use cases and requirements.

The W3C Web of Things standards seek to counter the fragmentation of the Internet of Things through the specification of building blocks that enable easy integration of IoT devices and services across IoT platforms and application domains. These building blocks complement and enhance the use of existing standards; provide a common description across different ecosystems, standards, and communities; and provide prescriptive definitions where appropriate.

As a W3C Interest Group, we are seeking to build a deeper understanding of stakeholder needs by investigating a wide variety of use cases across multiple verticals, including consumer, industrial, agricultural, environmental, retail, home, and smart city scenarios. This work is intended to identify demand for further standards-track work within the Web of Things Working Group, other W3C working groups as appropriate, and to align W3C Web of Things standards with related standards.

Join the Web of Things Interest Group.

This proposed charter is available on GitHub (rendered version here). Feel free to raise issues.

Charter Status See the group status page and detailed change history.
Start date dd-mm-yyyy (date of the "Call for Participation", when the charter is approved)
End date dd-mm-yyyy (Start date + 2 years)
Chairs Michael McCool (Intel Corp.), Sebastian Kaebisch (Siemens AG), and Michael Koster (Invited Expert)
Team Contacts Kazuyuki Ashimura (0.1 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, usually no more than 3 per year.

Motivation and Background

Currently the IoT is highly fragmented with a multitude of different standards and ecosystems which often do not easily interoperate. This is a concern as much of the value of the IoT can only be obtained when devices and services from different vendors can be used together. The standards developed by Web of Things (WoT) are intended to address this issue by defining additional building blocks to allow systems from different "ecosystems" to interoperate, focused on IoT standards for commercial and industrial deployments and ecosystems.

WoT building blocks bridge disparate IoT ecosystems by providing rich metadata that describes the data and affordances exposed to applications, through the Properties, Actions, Events interaction model, and the communications and security requirements for platforms to communicate effectively. The central documents are the WoT Architecture and WoT Thing Description.

The Web of Things Interest Group continues its work to support the Web of Things Working Group and to explore opportunities for new standards-track work within W3C. The priority in this fifth charter period is to refine the use cases and requirements for the ongoing development of Web of Things standardized building blocks by the WoT Working Group.


Scope Summary

  • Support the Web of Things Working Group
  • Organize and run interoperability test events, including events for specific vertical industries, to evaluate the current working assumptions in regard to the Web of Things
  • Develop use cases and functional requirements for the WoT Working Group to refine into technical requirements and specifications
  • Manage the Public Appearance of the Web of Things

relationship between WoT IG and WG The Web of Things Interest Group (WoT IG) is a forum for discussion of ideas relating to the Web of Things and is intended to complement the role of the Web of Things Working Group (WoT WG). The WoT IG will submit requirements originating from use cases to the WoT Working Group, and organize interoperability test events for hands-on evaluation of WoT standards and work in progress. The WoT IG will work with the WoT Community Groups to capture new use case and requirements, and collaborate on Plugfests, testing, and outreach. Conversely, the WoT IG will consider new topics that are submitted to it by the WoT WG.

The work on the use cases and management of public appearance will be performed in the IG Use Cases Task Force and IG Marketing Task Force, respectively.

PlugFest and Testing

An important activity is the operation of PlugFests to collect interoperability implementation experience and to validate the current working assumptions of the potential building blocks and features discussed in the Web of Things Working Group task forces (e.g., Thing Description). These events enable developers to get together to test their implementations and facilitates networking between partners and experts. The Interest Group will seek to encourage work on open source projects and community evaluation of the Web of Things. In more detail, PlugFests allow participants to:

Feature testing is a specific requirement of the Web of Things Working Group in order to create an implementation report for the publication of the Recommendation Track documents. The Web of Things working group will define a set of requirements that must be tested by at least two independent implementations. The Web of Things Interest Group supports the realization of the testing phase and, similar to PlugFest, helps with the inclusion of implementations, e.g. from open source projects and partners. Therefore, the Interest Group can provide test input that can be used by the Working Group, in addition to other inputs, to generate the implementation report.

Use Cases and Requirements

The Interest Group will identify requirements for standardization in two ways: first, by exploring use cases and requirements for concrete applications in a variety of verticals, including (but not limited to) consumer, industrial, agricultural, environmental (including energy management), retail, home, and smart city application scenarios; and second, through examining the requirements for integrating Web of Things with a broad range of IoT platforms and technologies. The exploration tasks that the Interest Group will undertake may include:

Further ideas for topics are expected from discussions and expert presentations of IoT projects, including for example, graph/linked data, edge computing, machine learning/artificial intelligence, accessibility, and sustainability. The Interest Group may also incubate work items for the Web of Things until they are ready for transfer to the W3C Recommendation Track, either in existing Working Groups, such as the WoT WG, or in new Working Groups.

During the previous Charter period, the group updated and expanded the Use Cases and Requirements document (published Note; latest Editor's draft on GitHub), which represents the needs of related SDOs like Conexxus, ITU-T SG20, OGC, ECHONET, ECLASS and OPC-UA as well as the W3C Member companies.

The Web of Things Interest Group also has and will investigate needs arising from security, privacy, internationalization, and accessibility.

Regarding security and privacy, a related document, Web of Things (WoT) Security and Privacy Guidelines, has been developed by the Web of Things Working Group which provides a threat analysis framework. The Web of Things Interest Group will attempt to convert the need to mitigate these threats in various use cases into a set of requirements and provide feedback to enrich the Web of Things (WoT) Security and Privacy Guidelines document.

Regarding internationalization, users may be either working wholly in a non-Latin script, or in an environment where different actors are using different languages. Any requirements and use cases arising from investigation of international use should, of course, then be reflected in the experience and/or implementation reports for identified building blocks and any primer, best practice, or test case documents.

Regarding accessibility, use cases will be analyzed to identify accessibility requirements whenever possible, and use cases specifically supporting accessibility will be sought out.

Marketing and Outreach

To reach out and collaborate with the community as mentioned in the scope, the Marketing Task Force works on promoting the W3C Web of Things in different ways such as Web presence, Social Media presence, and more.

The Marketing Task Force will also use the opportunity to do outreach with community groups such as with the W3C Web of Things Community Group. In addition, the TF will mediate between such community groups and the W3C Web of Things Working Group.

Out of Scope

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

The technical development of standards is not in scope for the Interest Group. Identified Recommendation Track opportunities will be handed over to appropriate W3C Working Groups if such a group exists, or within a dedicated Community Group or Business Group when incubation is needed.


The primary deliverable of the WoT Interest Group is an informative IG Note that identifies WoT Use Cases and Requirements. This Note collects use cases from various stakeholders, analyzes them for requirements, and relates those requirements to specific WoT building blocks.

Normative Specifications

The Interest Group will not deliver any normative specifications.

Other Deliverables

Other non-normative documents may be created such as:

  • experience reports for identified building blocks;
  • proposals for new building blocks, or approaches to satisfy identified requirements;
  • primers/tutorials, best practices, implementation guidelines, or test case documents (including security) to support WoT developers when designing applications and/or Things.

Note however that some of the above documents, such as experience reports or tutorials, may also be created by Community Groups related to the Web of Things.


Initial plan of events and deliverables. Additional events may be planned as well.

  • 2024Q2: Plugfest/F2F
  • 2024Q3: Use Cases and Requirements
  • 2025Q2: Testing (results contributed to WG)


For all deliverables, this Interest 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 Interest Group is encouraged to engage collaboratively with the horizontal review groups throughout development of each document. The Interest Group is also encouraged to proactively notify the horizontal review groups when major changes occur in its technical reports following a review.

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

WoT-related W3C Groups

Web of Things Working Group
Related Working Group of the Web of Things that specifies the WoT building blocks and publishes WoT-related W3C Recommendations and W3C Note documents. The latest Web of Things charter can be found here.
Web of Things Community Group
For collaboration on community outreach of the WG reports to increase adoption and implementation, as well as collecting feedback from the global community. Meetings held in English.
Web of Things Japanese Community Group
For collaboration on community outreach of the WG reports to increase adoption and implementation, as well as collecting feedback from the Japanese community. Meetings held in Japanese.

Other W3C Groups

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.
Automotive Ontology CG and Automotive Privacy Principles CG
For collaboration on ontologies and privacy 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 for IoT use cases.
Autonomous Agents on the Web Community Group
For collaboration on application of Web of Things in Agent-based systems in the Web.

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.
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 bindings 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.
For coordination on the development of the BACnet (ASHRAE 135-2020) binding for the W3C Web of Things .
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 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.
To coordinate retail use cases and show case in PlugFests.
For collaboration and coordination of the technical realization of the use of ECLASS in the W3C Thing Description.
Coordinating smart city and digital twin use cases and aligning terminology definitions.


To be successful, this Interest Group is expected to have 6 or more active participants for its duration, including representatives from key implementors and active Editors for each deliverable. The Chairs and Editors are expected to contribute half of a working day per week towards the Interest 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 "Positive Work Environment at W3C: Code of Conduct".


Technical discussions for this Interest 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 deliverables 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 Interest Group home page.

Most Web of Things (WoT) Interest Group teleconferences will focus on discussion of particular deliverables, 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 deliverable.

This group primarily conducts its technical work on GitHub issues, using a main repository for general topics and more specific repositories for individual deliverables. 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 and/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 on the mailing list by the end of the response period, the resolution will be considered to have consensus as a resolution of the Interest Group.

In some cases, resolutions can be announced and proposed in advance, by circulating an email to the group with concrete proposed text for the resolution. In these cases, the announcement can be considered the call for consensus (CfC) and when the resolution is made by the group, it can be considered final, at the discretion of the Chairs, if sufficient time (5 to 10 working days, at the discretion of the Chairs, as above) has been allowed for asynchronous input. This process will be followed especially for publication decisions which are then effective immediately.

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 Disclosures

The Interest Group provides an opportunity to share perspectives on the topic addressed by this charter. W3C reminds Interest Group participants of their obligation to comply with patent disclosure obligations as set out in Section 6 of the W3C Patent Policy. While the Interest Group does not produce Recommendation-track documents, when Interest Group participants review Recommendation-track specifications from Working Groups, the patent disclosure obligations do apply. For more information about disclosure obligations for this group, please see the licensing information.


This Interest 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.

Charter History

The following table lists details of all changes from the initial charter, per the W3C Process Document (section 4.3, Advisory Committee Review of a Charter):

Charter Period Start Date End Date Changes
Initial Charter 21 January 2015 31 March 2016
Charter Extension 1 April 2016 31 July 2016
  • Extended for rechartering process to complete
Rechartered 1 August 2016 31 December 2018
  • Clarified relation to chartered WoT Working Group
  • Changed scope to explore role of semantic technologies
Charter Extension 1 January 2019 30 June 2019
  • Matthias Kovatsch changed his affiliation and re-appointed as co-Chair.
  • Yongjing Zhang stepped down as co-Chair.
Charter Extension 1 July 2019 31 December 2019
  • Extended for rechartering process to complete
Rechartered 22 October 2019 30 June 2021
  • Simplified scope and deliverables to enable a broader set of Participants
  • Updated coordination groups
Charter Extension 1 July 2021 31 December 2021
  • Extended for rechartering process to complete
Charter Extension 1 January 2022 31 March 2022
  • Extended for rechartering process to complete
Rechartered 10 February 2022 31 December 2023
  • Updated to new charter templates
  • Updated coordination groups, including external liaisons
Charter Extension 22 December 2023 31 March 2024
  • Extended for rechartering process to complete

Change log

Changes to this document are documented in this section.