With the development of network technology, sensor technology, and communication technology, mankind has entered the era of the Internet of Things. In the era of the Internet of Things, a large amount of information, instructions, and data need to be transmitted between devices , which will inevitably affect the stability of communication technology. , Reliability puts forward higher requirements, so research on Internet of Things communication technology is an important topic for the communication industry. This article starts from the development of the Internet of Things and conducts research and analysis on the current physical network communication technology.
With the rapid development of network technology and communication technology, mankind is about to enter the 5G era from the 4G era. The arrival of the 5G era will bring faster network speeds, lay a communication foundation for the development of the Internet of Things, and also bring The spring of the Internet of Things. The Internet of Everything will bring huge changes to all aspects of human life, and the Internet of Everything will also bring huge communication pressure. Therefore, in the era of the Internet of Things, communication technology is the foundation, and the requirements for communication technology are higher than before, especially in the fields of industry, security, military and other fields, the security of communication technology is related to social security, national economy and people’s livelihood, and social development. Therefore, as the Internet of Things is about to develop rapidly, it is of great significance to carefully study the communication technology of the Internet of Things to occupy the high ground of the development of the Internet of Things and promote technological and social development.
Several commonly used IoT communication protocols
Since the Internet of Things has become a hot topic now, here we will give you a brief introduction to several communication protocols commonly used in Internet of Things devices.
1. Bluetooth Low Energy (BLE)
Bluetooth Low Energy (BLE) is an enhanced version of Bluetooth. It is also one of the earliest and most widely used wireless technologies and can communicate effectively within a short distance of about 10 meters. The concept of Bluetooth was proposed by Nils Rydbeck of Ericsson in 1989. Between 2001 and 2004, it was further optimized into lower-power, lower-cost versions such as the Bluetooth Low Energy (BLE) protocol or Nokia’s Bluetooth Smart. It is designed to maintain communication range while significantly reducing energy consumption. Due to this property, Bluetooth has become the dominant protocol for IoT devices. Currently, it is used in all major operating systems, including iOS, Android, Microsoft Mobile, Strawberry, OS X, Linux and Windows. The latest version of Bluetooth technology is 5.0 , which adds the innovative Internet Protocol Support Profile (IPSP). Currently, it has been fully developed and optimized for IoT devices.
2. WiFi
WiFi is another protocol widely used for communication between IoT devices. WiFi has become an integral part of our lives today because it uses a large amount of infrastructure, can transmit data quickly (up to hundreds of megabytes per second), and has the ability to handle large amounts of data transmission. For many designers of electronic devices, WiFi is the best choice because of the infrastructure it carries. The communication distance between two devices using WiFI is approximately 50 meters, which is much higher than that of devices using Bluetooth technology .
WiFi is based on the IEEE 802.11 series of standards, the first version of which was released in 1997. This version is capable of providing link speeds up to 2Mbit/s. Currently, the most commonly used standard for WiFi is 802.11n based on IEEE 802.11, but the use of 802.11ac is also growing rapidly. The latest version provides faster communication speeds than 802.11n. Although WiFi is very suitable for communication between IoT devices, its operation consumes relatively high energy. Regardless, it is currently the most powerful protocol for file transfer between most IoT devices.
3. ZigBee
ZigBee is a short-range wireless communication protocol based on the IEEE 802.15.4 standard. Its operating frequency is 2.4GHz and the data rate is 250kbps. The reason why ZigBee is suitable for effective communication between IoT devices is that it has the properties of low energy consumption, high scalability, security, persistence and high node count. Not only can the maximum number of nodes in the network reach 1024, and the maximum distance can reach 200 meters, but ZigBee can even use the 128-bit AES encryption algorithm .
The ZigBee specification (IEEE 802.15.4-2003) was first approved on December 14, 2004 and released in 2005. The ZigBee protocol is ideally designed for use in home automation and large industrial sites, where low power consumption is required and data exchange between homes or buildings is infrequent at low data rates. The user base that uses ZigBee as the preferred mode of communication between IoT devices is large.
The latest version of ZigBee is ZigBee 3.0. This version can be considered as a collection of all functions of several ZigBee wireless standards. Electronic systems that require low energy consumption, such as street lighting and electricity meters in urban areas, use the ZigBee protocol as the preferred mode of communication between IoT devices. The ZigBee protocol can also be used in security systems and smart homes.
4. Z-Wave
Similar to ZigBee, Z-Wave is a low-power radio frequency communication protocol primarily used in home automation systems and electronic devices such as light controllers and sensors. The frequency of the Z-Wave communication protocol is 900MHz and the range is 30-100 meters. Therefore, the interference between this protocol and other wireless protocols (such as WiFi, Bluetooth, ZigBee operating at 2.4GHz, etc.) is negligible. Its data rates range from approximately 40kbps to 100kbps.
The Z-Wave protocol is simpler compared to other protocols, so it can be easily developed at a faster rate. The radio frequency bands used in Z-Wave are country-specific. For example, 868.42 MHz SRD band (Europe), 900 MHz ISM or 908.42 MHz band (United States), 916 MHz band (Israel), 919.82 MHz band (Hong Kong), 921.42 MHz band (Australia/New Zealand), 865.2 MHz band (India).
5. Long-range wide area network (LoRaWAN)
Long Range Wide Area Network (LoRaWAN) is a communications protocol primarily used for long-range, battery-powered wireless IoT devices regionally, nationally, or globally. It is known for its ability to communicate over long distances with minimal power consumption and can detect signals despite noise levels. The protocol is primarily used in smart cities, where large networks have millions of devices connected to each other that run on smaller batteries and memory. The data rate of LoRaWAN is 0.3kbps to 50kbps.
Smart street lighting is a practical example of using the LoRaWAN protocol, where street lights are connected with a LoRa gateway using the LoRaWAN protocol. The gateway is then connected to a cloud application, which fully controls the brightness of the bulbs and adjusts them based on the natural lighting in the environment.
6. Near field communication (NFC)
Near Field Communication (NFC) is a simple and secure protocol that simplifies two-way communication between IoT devices. It mainly uses near-field electromagnetic induction from two loop antennas. It is designed for smartphones and allows users to conduct contactless payment transactions. It also helps users access electronic content and connect electronic devices. Basically, it extends the capabilities of contactless card technology so that IoT devices can share information at a distance of approximately less than 4 centimeters.
The data rate of the NFC protocol is 106kbps to 424kbps. Since the NFC protocol is a short-range communication protocol, it consumes less power. It takes less time to set up and doesn’t require device pairing. Also due to short-range communication, the potential for harmful interference to other networks in the environment is greatly reduced.
Development of Internet of Things
1.1 Gradual development of the Internet of Things
In 1999, MIT established the “Automatic Identification Center” and clarified the concept of the Internet of Everything. However, this concept mainly mentioned the use of radio frequency for the Internet of Things, and the scope was relatively small. In 2005, at the World Summit on Information Society in Tunisia, the concept of the Internet of Things was officially cited, and the concept of the Internet of Things officially entered the stage of history. Subsequently, countries around the world began to focus on the development of the Internet of Things. In November 2008, at the China Mobile Government Affairs Seminar held at Peking University, “Knowledge and Innovation 2.0” mobile technology was proposed. China’s Internet of Things process also began to accelerate. In 2009, the European Union proposed the European Internet of Things Action Plan. In the same year, Obama When he took office as the General Secretary of the United States, he proposed the concept of “Smart Planet” at a meeting of the American Industrial and Commercial Conference. As of 2010, the National Development and Reform Commission and the Ministry of Industry and Information Technology have issued a large number of IoT industry standards and related supporting policies, and the development of the IoT has been included in the “Government Work Report”. In 2011, the market size of the IoT industry has reached more than 260 billion yuan.
1.2 Application scope and cases of the Internet of Things
Broadly speaking, the physical network will penetrate into every corner of human life in the future. The so-called intelligent society, future society, and even the electronic devices in current science fiction movies are all areas that the Internet of Things will involve and include . Specifically, in other words, the Internet of Things will play an important role in intelligent transportation, environmental protection, public safety, government departments, smart homes, smart communities, industrial production, environmental monitoring, patient care, flower cultivation and other industries, and gradually extend to all aspects of human life. In the future, a large number of sensors will be installed in power grids, railways, bridges, tunnels, or other businesses. Gradually standardize, electronically, and standardize the daily business of each department of the college, and share various information resources to provide decision-making information for the college leadership and management, improve the management level of the college, and realize humanized and intelligent mobile services Office micro application platform.
3Research content
According to the new concept of “Internet”, the office model has also entered a new era, and mobile office micro-applications are gradually enriching people’s lives. Combining various workflow frameworks, the design uses HTML5 CSS3 as the mobile client interactive front-end , MY-SQL to store data, and the EasyUI SpringMVC Spring Hibernate framework to develop the server. Specific research applications are as follows:
(1) Develop mobile APP client software and use 3G and 4G wireless networks. Users can log in to the mobile office micro-application platform through their mobile phones, getting rid of time and location constraints and processing official documents and other business work anytime and anywhere.
(2) To achieve personalized office, the main functions include user login and logout, as well as providing some convenient daily office services. Operations can be customized according to personal habits, such as: maintaining personal information, setting to-do reminders or memos , etc.
(3) The entire process of official document circulation is paperless, with workflow as the core, and the entire process from the creation, editing, review, circulation, sending, archiving, and review of official documents is processed online or through a mobile client .
(4) Through the SMS platform or point-to-point instant messaging technology, real-time reminders and information push are provided to node users during the official document processing process, saving time and improving efficiency.
(5) With the help of cloud services or internal email platforms, communication and communication between users can be realized, and information transmission and sharing of online resource files can also be realized.
4 Conclusion
In short, the application of mobile office micro-application platform is also a new office model in vocational schools. The SSH EasyUI MYSQL H5 framework based on workflow will improve the efficiency of administrative offices in vocational schools. The information construction of vocational colleges and the integration of mobile office micro-application platforms will add personalized and characteristic effects to administrative offices. Therefore, the above applied research will also draw lessons from more
Optimize more mature cases. Big data analysis is combined to complete the scalability of the platform, and the reliability is verified by ease of use, etc. However, the specific practical effects have yet to be further implemented and verified, and continuous improvement is required .
Keywords: nb-iot dtu