## 2 The Role of IoT Devices in Smart Buildings
### The Platform and Components of IoT-Based Devices  
The Internet of Things (IoT) is a network of interconnected devices that share, communicate, and use real-world data to deliver services to individuals, organizations, and society. The IoT is a technology that links physical devices to the Internet. The IoT platform connects devices and objects with built-in sensors, integrating data from huge devices and utilizing analytics to provide the most useful information [18]. IoT technologies have a variety of applications, such as detection systems, communications technologies, cloud technologies, and location technologies.  
* **IoT sensors**: The sensors save all of the information on the server and display it as required, for example, to draw energy consumption patterns of building workloads and minimize power usage [19]. This benefits customers and also improves the outside environment of the building. The main components of an effective IoT system are depicted in Figure 2.
* **IoT gateways**: A gateway's principal function in telecommunications is to act as a link between different communications systems. With respect of communication options, interfaces, and protocols, these technologies can vary [20].
* **Cloud infrastructure**: The importance of cloud infrastructure in IoT clouds for IoT services, such as vehicle-to-vehicle (V2V) connectivity, real-time health tracking, and commercial IoT, is higher than simple computing services [21]. The most popular endeavor is smart device scheduling. Smart device scheduling effectively controls device functionality for end-users and also saves money and energy. At the same time, it is guaranteed that the users' comfort is not endangered. In this case, the energy management system schedules the devices efficiently in response to the external data and user input [22].
* **Network infrastructure**: In the coming years it is expected that cellular-based technologies that install low power wide area networks (LPWAN) would be important growth drivers in the Internet of Things connectivity of smart buildings. There are several different connectivity options available, such as LTE and LoRAWAN, which are cellular-based, as well as Wi-Fi-based options, that can be used to link Internet of Things devices to each other and the cloud.  
Figure 1: IoT-based systems in smart buildings.  
These networks can function over a considerably greater distance and at much faster data speeds [23].  
Smart buildings, which use the Internet of Things (IoT) to connect building operations, enable activities, such monitoring building temperature, safety, and maintenance, which are easier to control via mobile devices and computers. Building management systems, IoT sensors, artificial intelligence, and machine learning are some of the technologies that can be used in a smart building to regulate its operation.  
* **Building management systems**:  
Building management systems, often referred to as building automation systems, have an important part in energy management in commercial and industrial buildings [24]. Smart buildings provide better convenience for facility managers, increase safety and comfort for building occupants, and reduce facility running costs through automation, sensors, and remote features.