Smart device
A smart device is an electronic device, generally connected to other devices or networks via different wireless protocols (such as Bluetooth, Zigbee, near-field communication, Wi-Fi, NearLink, Li-Fi, or 5G) that can operate to some extent interactively and autonomously. Several notable types of smart devices are smartphones, smart speakers, smart cars, smart thermostats, smart doorbells, smart locks, smart refrigerators, phablets and tablets, smartwatches, smart bands, smart keychains, smart glasses, and many others. The term can also refer to a device that exhibits some properties of ubiquitous computing, including—although not necessarily—machine learning.
Smart devices can be designed to support a variety of form factors, a range of properties pertaining to ubiquitous computing and to be used in three main system environments: physical world, human-centered environments, and distributed computing environments. Smart homes indicate the presence of sensors and some detection devices, appliances, and a database to control them.
In 1991, Mark Weiser proposed three basic forms for ubiquitous system devices: tabs, pads and boards.[1]
These three forms proposed by Weiser are characterized by being macro-sized, having a planar form and by incorporating visual output displays. These were also envisioned more as information appliances. If each of these three characteristics is relaxed, this range can be expanded into a much more diverse and potentially more useful range of ubiquitous computing devices.[2]
Smart devices are typically composed of a hardware layer (including a radio that transmits signals), a network layer (through which devices communicate with each other), and an application layer (through which end users deliver commands). These layers often include the following characteristics:
Common types of smart devices include:
Weiser's vision for ubiquitous computing can be summarized in terms of two core properties:
It is proposed that there are two additional core types of properties for ubiquitous computing systems:[2]
However, it is hard to fix a closed set of properties that define all ubiquitous computing devices because of the sheer range and variety of ubiquitous computing research and applications. Rather than to propose a single definition for ubiquitous computing, a taxonomy of properties for ubiquitous computing has been proposed, from which different kinds or flavours of ubiquitous systems and applications can be composed and described.[2]
The term smart device environments has two meanings. First, it can refer to a greater variety of device environments. Three different kinds of environments for devices can be differentiated:[2]
Second, the term smart device environments can also refer to the concept of a smart environment which focuses more specifically on the physical environment of the device. The physical environment is smart because it is embedded or scattered with smart devices that can sense and control part of it.