1 of 22

W3C Web of Things Community Group

TPAC 2023 - Quick Intro to WoT

Cristiano Aguzzi - Ege Korkan

September 11th and 14th, 2023

1

Web of Things Community Group | TPAC 2023 | 2023-09-14

2 of 22

With a browser, you can access all the content in the Web

2

Web of Things Community Group | TPAC 2023 | 2023-09-14

3 of 22

You don’t have that with IoT

​

WoT is here to fix it!

3

Web of Things Community Group | TPAC 2023 | 2023-09-14

4 of 22

What is different in IoT?

​

  • Not just HTTP, welcome CoAP, MQTT, Modbus, OPC UA, BACnet and more…
  • Not just about a server serving data, there is influence of/on the real world
  • Walled gardens
    • No interoperability across vendors
    • Dependency to SDKs

​

Overall, there is a fragmentation problem

4

Web of Things Community Group | TPAC 2023 | 2023-09-14

5 of 22

A small part of the landscape

5

Web of Things Community Group | TPAC 2023 | 2023-09-14

6 of 22

Each domain has its own set of protocols, standards, tools, vocabularies

6

Web of Things Community Group | TPAC 2023 | 2023-09-14

7 of 22

Web of Things Now

7

Was a proposal on how to build REST APIs for IoT devices

Is about describing any kind of API for IoT devices using any protocol

Web of Things Community Group | TPAC 2023 | 2023-09-14

8 of 22

Now 4 normative deliverables (from WG), participants from over 35 organizations, dozens of implementations

8

Web of Things Community Group | TPAC 2023 | 2023-09-14

9 of 22

Mashups at Standardization Events (since 2016!)

9

Web of Things Community Group | TPAC 2023 | 2023-09-14

10 of 22

10

Family of W3C Standards

Open Source

Market Adoption

Developer Friendly

(Re)Usable API Descriptions for every Thing

Royalty Free and Open

Web of Things Community Group | TPAC 2023 | 2023-09-14

11 of 22

Web of Things, not a Protocol

11

Narrow Waist Model

Network Protocols

Bindings

Interaction Affordances

Semantics

Applications

Thing

Description

Web of Things Community Group | TPAC 2023 | 2023-09-14

12 of 22

Core Specification: Thing Description (TD)

12

Protocols

Domain Knowledge via

Semantic Annotations

Semantic Context

Security

Properties

Data Schema

Forms

Links

Actions

Data Schema

Forms

Events

Data Schema

Forms

JSON-LD Serialization

Effect in the real world

Discovery and

Usage by Clients

Web of Things Community Group | TPAC 2023 | 2023-09-14

13 of 22

What to do with a TD

  • Communicating with the Thing
  • Device Proxying and Protocol Translation
  • UI generation
  • Device Management
  • Business/Application Logic Composition (MAS and Mashups)

13

Web of Things Community Group | TPAC 2023 | 2023-09-14

14 of 22

Quick Deeper look into the Thing Description

14

Version 1.1 almost out!

Web of Things Community Group | TPAC 2023 | 2023-09-14

15 of 22

Deeper look: Thing Level

15

{

"@context": [

"https://www.w3.org/2022/wot/td/v11",

{"iot":"http://iotschema.org"}

],

"@type":"SprinklerStation",

"id": "urn:dev:ops:Agriculture-7331",

"title": "SoilStation",

"description": "A soil management station for use in agriculture",

"securityDefinitions": { "basic_sc": {"scheme": "basic"} },

"security": "basic_sc",

"properties": {

"temperature": {...}

},

"actions": {

"startSprinkler": {...}

},

"events": {

"tooDry": {...}

},

"links":["href":"docs", "rel":"about", "type":"text/html"]

}

Thing

Metadata

Definitions of

Interaction Affordances

Semantic Annotations

Security

Metadata

Links to other

Documents

Web of Things Community Group | TPAC 2023 | 2023-09-14

16 of 22

Deeper look: Interaction Level

16

"properties": {

"temperature": {

"title": "Temperature",

"type": "number",

"unit": "Celsius",

"forms": [...]

},

"actions": {

"startSprinkler":{

"description": "Run sprinkler for a set time",

"input": {

"type": "object",

"properties": {"timeout": {...}},

},

"forms": [...]

},

"events": {

"tooDry": {

"data": {"type": "string"},

"forms": [...]

}

Interaction

Metadata

JSON Schema

Concrete Protocol Information

​

Web of Things Community Group | TPAC 2023 | 2023-09-14

17 of 22

Deeper look: Protocol Level

17

​

"forms": [

{

"href": "http://example.com/light/currentdimmer",

"contentType": "application/json",

"op": "readproperty",

"htv:methodName": "GET"

},

{

"href": "mqtt://example.com/",

"op": "observeproperty",

"mqv:filter": "example/light/currentdimmer”,

"mqv:controlPacket": "subscribe"

}

]

Protocol and URI

of the Resource

​

Intended WoT

Operation

​

Protocol Specific Vocabulary

Web of Things Community Group | TPAC 2023 | 2023-09-14

18 of 22

Other WoT Specifications

18

Web of Things Community Group | TPAC 2023 | 2023-09-14

19 of 22

19

Binding

Templates

Scripting

API

Common Reference, Deployment Patterns,

Relationship between specifications

Extending TDs for different protocols, media types, ecosystems, etc.

How to find TDs in a network, TD management via a REST API

Programming API for building Consumer and Thing applications

Architecture

REC

Discovery

REC

A mechanism for creating subset of TD for less flexibility but easier implementability

Profile

REC*

Use Cases and Requirements

Where different WoT specifications get motivation for new features

Web of Things Community Group | TPAC 2023 | 2023-09-14

20 of 22

Where to Learn More?

20

https://www.w3.org/WoT/

Official Web Page of W3C WoT

@W3C_WoT

Read documentation and

watch some videos on the official page

Try node-wot , ediTDor and Playground

​

Do a simple tutorial

Join one of the CG office hours

Web of Things Community Group | TPAC 2023 | 2023-09-14

21 of 22

Stay in Touch with the CG

21

Web of Things Community Group | TPAC 2023 | 2023-09-14

22 of 22

WoT Related Events at TPAC

​

WoT CG Calendar: https://www.w3.org/groups/cg/wot/calendar/

WoT WG Calendar: https://www.w3.org/groups/wg/wot/calendar/

22

Web of Things Community Group | TPAC 2023 | 2023-09-14