The concept of the Internet of Things (IoT) was proposed long ago, with the term being introduced at the International Conference on Mobile Computing and Networking held in the United States at the end of the 20th century. The concept was first proposed by Professor Ashton from the MIT Auto-ID Lab, who, while researching RFID technology, suggested a solution that combined item coding, internet technology, and RFID. The initial proposal was based on RFID technology, the internet, and EPC standards, utilizing wireless data communication technology and radio frequency identification technology to construct an internet that enables global sharing of physical object information. This concept also laid the foundation for the first wave of IoT enthusiasm in 2003.
By 2005, the definition and scope of the Internet of Things had changed significantly, expanding beyond just RFID-based applications. Although there is currently no unified standard definition for IoT in China, fundamentally, the Internet of Things represents a convergence of applications and technological advancements that emerge after a certain stage of modern information technology development. It integrates various sensing technologies, artificial intelligence, modern networking technologies, and automation technologies, enabling intelligent dialogue between people and objects, thereby creating a smart world.
The application technology of the Internet of Things is regarded as the third revolutionary innovation in the information industry. The essence of the Internet of Things can be summarized in three aspects: first, the characteristics of the internet, which require the interconnection of objects through a network; second, the characteristics of identification and communication, where the ‘objects’ included in the IoT concept must possess the capability for automatic identification to enable machine-to-machine (M2M) communication; and third, the intelligent characteristics, where the network system should have features of intelligent control, automation, and self-feedback.
From a technical architecture perspective, the Internet of Things can be divided into three layers: the perception layer, the network layer, and the application layer, as illustrated in the figure below.
The perception layer consists of various sensor gateways and sensors, including temperature sensors, carbon dioxide concentration sensors, QR code tags, humidity sensors, cameras, RFID tags and readers, GPS, and other sensing terminals. The role of the perception layer is akin to human senses such as vision, touch, taste, and hearing; it is the source for the IoT to acquire and identify objects and collect information, with its main functions being object recognition and information collection.
The network layer comprises the internet, private networks, wireless and wired communication networks, network management systems, and cloud computing platforms. The network layer is analogous to the human brain and central nervous system, primarily responsible for transmitting and processing the information obtained from the perception layer.
The application layer serves as the interface between the Internet of Things and users (including individuals, organizations, or other systems). It integrates with industry development application needs to realize intelligent service applications of the Internet of Things.
