Web of Things in a Nutshell
Making networks of “smart things” found in the actual world on a huge scope has become the objective of the ongoing exploration in the field of data communication, networks, and embedded devices. Instead of working in different environments for these smart devices that do not have a common interface for communication, it is possible to integrate the Web into it. Subsequently, smart devices become simpler to expand upon. In such an engineering, mainstream Web advancements like HTML, JavaScript, Ajax, PHP, Ruby, can be utilized to create platforms and applications including these embedded devices, and clients can use notable Web components to communicate with and share these gadgets.
In the Web of Things concept, smart things and their services are fully integrated into the Web by reusing and adapting technologies and patterns that are used for traditional Web content. [3] Explaining it in a more understanding way, Web components are integrated into embedded devices, and REST architectural style is applied to assets in the physical world. The purpose of using RESTful routing is to create resources on the internet that are independent of each other and can be handily reused. REST is considered as the architectural style of the Web. (implemented by URIs, HTTP, and standardized templates like HTML) [3]
The resources on the Web are abstracted so that the users have an option to choose the best possible interface for their devices. The data from the embedded devices is extracted in understandable formats such as XML and JSON. By understandable, we mean that these can interact with machines as well as provide some meaningful information to the developers. The general thought is that the Web is being utilized as a decentralized data framework for effectively uncovering new applications straightforwardly or by implication using smart devices.
Defining Web of Things
The Web of Things (WoT) is a computing idea that portrays a future where regular objects are completely incorporated with the Web. The Web of Things is considered as a subset of the Internet of Things (IoT) which focuses on standards and communication protocols that govern the interaction between the user and a smart device. It uses frameworks such as REST, HTTP, URIs and Webhooks to create applications and services that combine and interact with a variety of network devices. [2]
The essential for WoT is for the “things” to have embedded controllers that empower correspondence with the Web. Such smart gadgets would then have the option to communicate with one another utilizing existing Web guidelines. The description of “things” is considered a major portion in WoT. A Thing is an abstraction of a physical or virtual entity.[1] It includes the metadata and interfaces associated with it along with the standards it uses to communicate in a heterogeneous fashion. The description metadata is a must in Thing Description (TD). [1]
The methods with which a Thing can interact can be of four types:
- Properties
The properties of an object are its attributes. Properties can include movement, temperature, color, sight, length, weight, etc. Things can make the properties observable when there is a change in state.
2. Actions
The tasks performed by a Thing or its movement is considered as actions. These actions are invoked by a function and can manipulate the properties of a Thing. Usually, actions follow each other until a resulting state is reached.
3. Events
The actions performed by a Thing lead to different states of the Thing. The transition from states is termed events. These are triggered by functions that are as defined in the properties. A succession of events happens along with actions in between.
4. Navigation affordance (Web links)
How one Thing interacts with another is defined in its navigation affordance. This can be direct communication or indirect via a secondary entity or interface. This also includes resources related to a Thing such as manuals, catalogs for spare parts, CAD files, a graphical UI, or any other documents on the web.[1]
The Data Schema of a Thing is another important feature of a Thing. It describes the variable's relationships with each other and how they are accepted by the environment. The Security Configuration of a Thing helps to secure the data when it is being transmitted or is at its initial stage in storage. To be a Thing, at least one of described methods should be associated with it.
In a nutshell, the Web of Things is an addition to the Internet of Things, with the inclusion of a web interface.
References
[1] Web of Things (WoT) Architecture, 9 April 2020
[2] https://www.techopedia.com/definition/26834/web-of-things-wot
[3] Guinard, D., Trifa, V., Mattern, F., & Wilde, E. (2011). From the Internet of Things to the Web of Things: Resource-oriented Architecture and Best Practices. Architecting the Internet of Things, 97–129.
