What is the Internet of Things? What's the difference between it and sensor networks?

Sensor network sensor network definition: a wireless network composed of randomly distributed tiny nodes that integrate sensors, data processing units and communication units in a self-organizing manner. Function: With the help of the sensor built in the node, we can measure the signals of heat, infrared, sonar, radar and seismic waves in the surrounding environment, so as to detect material phenomena including temperature, humidity, noise, light intensity, pressure, soil composition, size, speed and direction of moving objects. The computer network technology represented by the Internet is a great achievement of computer science in the 20th century, which has brought profound changes to our lives. However, at present, no matter how powerful the network function is and how rich the network world is, it is still virtual and separated from the real world in which we live. In the network world, it is difficult to perceive the real world, and many things are still impossible. The times call for new network technology. Sensor network is a brand-new network technology under this background. It integrates sensor, low power consumption, communication and MEMS technology. It can be predicted that in the near future, sensor networks will bring revolutionary changes to our lifestyle. Wireless sensor network Wireless sensor network technology is a typical interdisciplinary strategic high technology, which can be widely used in GF military, national security, environmental science, traffic management, disaster prediction, medical and health care, manufacturing, urban information construction and other fields. Wireless sensor networks are composed of many wireless sensor nodes with the same or different functions. Each sensor node consists of data acquisition module (sensor, A/D converter), data processing and control module (microprocessor, memory), communication module (wireless transceiver) and power supply module (battery, DC/ AC energy converter). The latest development of MEMS technology makes it possible to miniaturize sensors. The development of microprocessor technology promotes the intelligence of sensors, and the integration of MEMS technology and radio frequency (RF) communication technology promotes the birth of wireless sensors and their networks. Traditional sensors are gradually realizing miniaturization, intelligence, informationization and networking, and are experiencing a development process from traditional sensors to intelligent sensors to embedded Web sensors. The international representative and influential practical and R&D projects of wireless sensor networks include Rem battlefield sensor system, network-centric warfare (NCW) and intelligent sensor network (SSW), smart dust and Intel? Mote, Smart -Its project, SensIT, SeaWeb, habitat monitoring project, British national grid, etc. In particular, this year's newly trial-produced low-cost US Army "Wolf Pack" ground wireless sensor network marks the latest breakthrough in technology and tactics in the field of electronic warfare. Ohio is developing a wireless sensor network system. This system can disperse electronic tripwires anywhere to detect moving targets with high metal content. For civilian use, developed countries such as the United States and Japan have applied this technology to many fields on the basis of continuous research and development. Intel and the University of California, Berkeley, led the research on dust technology. They have successfully manufactured a full-function sensor the size of a bottle cap, which can perform functions such as calculation, detection and communication. In 2002, researchers from Intel Research Laboratory connected 32 sensors the size of prescription bottles to the Internet to read the climate of Duck Island in Maine and evaluate the situation of Haiyan's nest. In the second quarter of 2003, they used 150 second-generation sensor with D-type micro-battery to evaluate the status of these nests. Their purpose is to enable researchers around the world to monitor sensitive wildlife and their habitats in a non-invasive and non-destructive way. The company has developed a wireless sensor network system for home care. According to the demonstration, the trial-produced system helps the family life of the elderly, patients with Alzheimer's disease and the disabled by embedding semiconductor sensors in shoes, furniture and household appliances. The system uses wireless communication to connect all sensors, which can efficiently transmit necessary information, thus facilitating patients to receive care and reducing the burden of nursing staff. The wireless sensor network system was completed by Intel Corporation in cooperation with the families of patients with Alzheimer's disease, which lasted for one year and was put into trial in the second half of 2004. Hitachi and YRP Ubiquitous Network Research Institute announced the development of the world's smallest sensor network terminal on June 24th, 2004. The terminal is an active wireless terminal with battery, which can be equipped with various sensors such as temperature, brightness, infrared ray and acceleration. Imagine the application of wireless sensors in building, home and safety management. Mitsubishi electric has successfully developed a small wireless module with low power consumption for sensor networks. Ad hoc networks can be built using specific low-power wireless networks. The goal is to replace the current home security network built by private lines, and it is planned to reach the practical level in 2005 ~ 2006. Specifically, it is to cooperate with infrared sensors to detect whether there are people, with acceleration sensors to detect the vibration of windows and furniture, with magnetic sensors to detect the opening and closing of doors, and so on. In San Francisco, 200 networked motes were placed on the Golden Gate Bridge. These dust particles are used to determine the swinging distance of the bridge from side to side-accurate to several feet in strong winds. When the dust detects the moving distance, it will transmit information through the microcomputer network. This information finally reaches a more powerful computer for data analysis. Any abnormal reading inconsistent with the current weather conditions may indicate that there are hidden dangers in the bridge. The research on modern wireless sensor network and its application in China started almost at the same time as that in developed countries. 1999, 1999 first appeared in the research report of information and automation field of "Research on the Pilot Field of Knowledge Innovation Project" of China Academy of Sciences, as one of the five major projects proposed in this field. With the deepening of the pilot work of knowledge innovation, in 20001year, the Chinese Academy of Sciences established the Microsystems R&D Center based on Shanghai Microsystems Institute to lead the related work of the Institute, and deployed several major research projects and directional projects in the direction of wireless sensor networks through the center. Participating units include Shanghai Microsystems Research Institute, Acoustics Research Institute, Microelectronics Research Institute, Semiconductor Research Institute, Electronics Research Institute, Software Research Institute and University of Science and Technology of China. The research platform of sensor network system has been initially established, and great progress has been made in wireless intelligent sensor network communication technology, micro-sensors, sensor nodes, cluster points and application systems. In September, 2004, the related achievements were exhibited on a large scale in Beijing, and some of them have been used in practical engineering systems. Many universities in China have also set off a research upsurge of wireless sensor networks. Tsinghua University, China University of Science and Technology, Zhejiang University, Huazhong University of Science and Technology, Tianjin University, Nankai University, Beijing University of Posts and Telecommunications, Northeastern University, Northwestern Polytechnical University, Southwest Jiaotong University, Shenyang Gong Li University and Shanghai Jiaotong University have carried out basic research work on wireless sensor networks. Some enterprises, such as ZTE, have also joined the research of wireless sensor networks. Sensor networks are used in civil fields, involving urban public safety, public health, safe production, intelligent transportation, smart home, environmental monitoring and other fields. At present, there are few large enterprises engaged in sensor network applications in China, and small enterprises are booming. Beijing Dingtian Software Co., Ltd. is mainly engaged in the construction of urban public safety emergency command system, and undertakes Yangzhou e-government and Yangzhou emergency command system. Shanghai Electric Appliance Research Institute is mainly engaged in intelligent transportation projects and undertakes intelligent transportation projects in Shanghai and overseas. Jiaxing Zhongke Wireless Sensor Network Technology Co., Ltd. has a good technical background in digital waterway, urban emergency system and airport monitoring, and related projects are under way. Shenyang Neusoft, Beida Jade Bird, Yiyang ICT and other enterprises have also set foot in the application of sensor networks. At present, it mainly involves e-government and moves towards public security emergency command system. Internet of Things The so-called "Internet of Things" refers to a huge network formed by the combination of various information sensing devices, such as radio frequency identification (RFID) devices [1], infrared sensors, global positioning systems, laser scanners and other devices with the Internet. Its purpose is to connect all items with the network for easy identification and management. The Internet of Things is established by ubiquitous network technology, among which the most important technology is RFID electronic tag technology. Based on simple RFID system, combined with existing network technology, database technology, middleware technology, etc. It has become the development trend of RFID technology to build the Internet of Things consisting of a large number of networked readers and numerous mobile tags. In this network, the system can identify, locate, track, monitor and trigger corresponding events automatically and in real time. The Internet of Things is also called "sensor network". The computer network technology represented by the Internet is a great achievement of computer science in the 20th century, which has brought profound changes to our lives. However, at present, no matter how powerful the network function is and how rich the network world is, it is still virtual and separated from the real world in which we live. In the network world, it is difficult to perceive the real world, and many things are still impossible. The times call for new network technology. Wireless sensor network is a brand-new network technology under this background. It integrates sensor, low power consumption, communication and MEMS technology. It can be predicted that in the near future, wireless sensor networks will bring revolutionary changes to our lifestyle. Definition: A wireless network composed of randomly distributed tiny nodes through self-organizing integration of sensors, data processing units and communication units. Chinese name: wireless sensor network; ; Abbreviation: WSN function: With the help of sensors built in the nodes, it can measure signals such as heat, infrared, sonar, radar and seismic waves in the surrounding environment, so as to detect material phenomena including temperature, humidity, noise, light intensity, pressure, soil composition, size, speed and direction of moving objects. At present, the relatively formed framework of distributed network integration is EPC network proposed by EPCglobal. EPC network is mainly aimed at the logistics field, and its purpose is to increase the visibility and control of supply chain, so that the whole logistics field can obtain greater economic benefits with the help of RFID technology. The key technologies of EPC network include: EPC coding: 64-bit, 96-bit and 256-bit ID coding. For the sake of cost, 64-bit and 96-bit coding are mainly used now. EPC code is divided into four fields, namely: ① header, which identifies the version number of the code, so that the electronic product code can adopt different lengths and types; (2) product managers, such as product manufacturers; (3) Product category; ④ The unique number of the project. Savant is the middleware between reader and enterprise application, which provides a series of computing functions for enterprise application. Its main task is to reduce the amount of data transmitted from readers to enterprise applications, filter, collect and calculate tag data read by readers, and Savant also provides interoperability with ons, PML servers and other savants. Object name service, similar to domain name server DNS, ONS provides the service of parsing EPC code into a URL or a group of URLs, through which further information about EPC-related products can be obtained. Information service stores product-related information in PML format, which can be retrieved by other applications and returned in PML format. The stored information can be divided into two categories: one is the historical event record related to time, such as the original RFID reading event (when the tag was recorded and read by which reader), and the high-level activity record such as the transaction event (recording the tag involved in the transaction); The other is the inherent attribute information of the product, such as production time, shelf life, volume, color and so on. Physical Markup Language (PML) is an extension of XML and is considered as a unified standard to describe all natural objects, processes and environments. In EPC network, all information about goods is described by Physical Markup Language (PML), which is the standard format for information storage and exchange in EPC network.