The Internet of things is a network that connects any item with the Internet according to the agreed protocol through information sensing devices such as radio frequency identification (RFID), sensors, global positioning system, laser scanners, etc., for information exchange and communication, so as to realize intelligent identification, positioning, tracking, monitoring and management. In general, it is a network that can realize “world perception”.

The data acquisition and monitoring system, also known as SCADA (Supervisory Control and Data Acquisition) system, is a computer-based production process control and scheduling automation system. It can monitor and control the operating equipment on site to achieve various functions such as data acquisition, equipment control, measurement, parameter adjustment, and various signal alarms, which is to achieve “perception” in specific application fields.

The Internet of Things technology is not a unfamiliar concept for automation engineers. Because, whether it is on-site equipment in factories, power grids, water supply networks, gas pipelines, railways, bridges, tunnels, hydrological and hydraulic systems, or even our spacecraft and satellite operation monitoring, they are all achieved through the “Internet of Things” network that connects things. However, we traditionally refer to the “Internet of Things” applications in these professional fields as SCADA systems. Of course, from a definition perspective, the Internet of Things is a broader “perception” network. Through the Internet of Things, we can extend “perception” to every device, every product, and even every person, achieving monitoring and management of static objects, positioning and tracking of dynamic objects, and identifying products, in order to truly achieve the goals of “perceiving China” and “smart Earth”. Therefore, strictly speaking, the Internet of Things is not only an extension of the concept and application of SCADA, a traditional “perception” technology, but also a qualitative improvement to the development of SCADA technology.

With the development of network and communication technology, the Internet of Things (IoT) technology will inevitably promote the transformation and upgrading of SCADA system architecture, making the application fields of SCADA systems more and more extensive. In addition to traditional industries such as water supply, gas supply, environmental protection, energy, rail transit, airports, railways, power, petroleum, and petrochemicals, it will also be widely used in the daily work and life of the public, as well as various other fields. Ultimately, SCADA, as a vertical and specific application system of the Internet of Things, will truly develop into a smart network that perceives the world.

Three Application Architectures of the Internet of Things

The Internet of Things fully utilizes the new generation of IT technology in various industries, and D33025 connects the physical world with the information world. There are three architectures for IoT applications:

(1) RFID based IoT application architecture electronic tags may be the most flexible among the three technological systems to transform “things” into intelligent objects. Its main application is to label mobile and non mobile assets, achieving various tracking and management.

(2) The IoT application architecture based on sensor networks mainly refers to wireless sensor networks (WSN), which are composed of a group of “autonomous” wireless sensors distributed in free space, working together to monitor specific surrounding environmental conditions, including temperature, humidity, chemical composition, pressure, sound, displacement, vibration, pollution particles, etc. A node (or Mote) in WSN typically consists of a wireless transceiver, a microcontroller, and a power supply. WSN is generally an ad hoc or self reconfiguring network, including wireless mesh networks and mobile self reconfigurable networks (MANET).

(3) The M2M concept and technical architecture recognized by the industry for IoT application architecture based on M2M should cover the widest range, including both wired and wireless communication methods.

M2M covers and expands the traditional SCADA system in industrial informatization (integration of industrialization and informatization).

Design of 3 New SCADA Systems

3.1 Traditional SCADA system

A typical SCADA system consists of a monitoring center, communication network, and remote data acquisition terminals. The monitoring center is a data processing and display system, also known as the upper computer HMI (Human Machine Interface) – the human-machine interface system consists of software and hardware, including servers, administrator stations, and operator stations. The software uses dedicated SCADA system software. The communication network of SCADA system can be generally divided into two categories:

Wired and wireless. Remote data collection terminals refer to various intelligent data collection devices, commonly known as lower level computers, such as various RTUs, PLCs, and intelligent control devices. The network topology of the SCADA system is shown in Figure 1:

 

The SCADA system has evolved from the initial host control system and distributed control system to today’s networked control system. SCADA has evolved from a closed system with proprietary protocols to an open system with Ethernet and TCP/IP protocols as the mainstream.