The three levels of the Internet of Things system are perception layer, network layer and application layer.
1, perception layer
Perception layer includes sensing devices represented by sensors, identification devices represented by RFID, GPS and other positioning and tracking devices, as well as intelligent terminals that may integrate some or all of the above functions. The perception layer is the source of IoT information and data so as to achieve the purpose of comprehensive perception of data.
2. Network layer
The network layer includes the access network and core network. Access network can be wireless proximity access, such as wireless LAN, ZigBee, Bluetooth, infrared, or wireless long-distance access, such as mobile communication networks, WiMAX, etc., but also other forms of access, such as wired network access, fieldbus, satellite communications.
The network layer is carried by the core network, which is usually an IPv4 network. The network layer is the transmission layer for IoT information and data, and transmits the data collected in the sensing layer to the application layer for further processing.
3. Application Layer
The application layer analyzes and processes the data transmitted through the network layer, and ultimately provides users with a wealth of specific services, such as smart grids, smart logistics, telemedicine, smart transportation, smart homes, smart cities and so on. Relying on the data provided by the perception layer and the transmission of the network layer, the corresponding processing may again be fed back to the perception layer through the network layer.
The main application areas of the Internet of Things:
1, Industry and Manufacturing
The Internet of Things is widely used in industry and manufacturing. By connecting sensors and devices to the Internet, real-time monitoring and control of production lines, equipment status and supply chain, etc., to realize intelligent production and logistics management and improve production efficiency and quality.
2, building and city
IoT can be used for intelligent management of buildings and cities. By connecting sensors and devices, it enables the control and monitoring of smart homes, smart buildings and smart cities, improving energy efficiency, optimizing traffic flow, and improving environmental monitoring.
3, Agriculture and Rural
The Internet of Things can be used to realize the development of smart agriculture in the field of agriculture. Through sensor networks, remote monitoring and automated control, it can realize the monitoring and management of soil moisture, weather conditions, irrigation systems, etc., and improve the yield and quality of crops.
4, medical and health
IoT can be used in the field of medical and health management. By connecting smart medical devices, health monitoring sensors and mobile apps, it enables remote monitoring, positioning and tracking of patients' health conditions and provides personalized medical services and health management.