Expository Essay on SCADA Technology in Computer Networking

Introduction

SCADA is an acronym that stands for Supervisory Control and Data Acquisition. This is a computer system that is utilized in the collection and analysis of real-time data (Li, Duo, Yoshizumi & Mai Kiuchi 311). These systems are used in monitoring and controlling a piece of plant equipment in many industries such as transport, telecommunications, oil and gas refining, energy and water, and waste control. SCADA can be said to be a system of software and hardware components that enable industrial organizations to be able to control industrial procedures remotely or locally, monitor, collect and even process real-time data, directly interact with installations and other devices such as motors, valves, pumps, sensors and many more via the human-machine interface (HMI) software (Li et al. 367). This system also allows industrial organizations to record events into a log file. The SCADA systems are vital for all industrial organizations as they help in the maintenance of efficiency, data processing to ensure smarter decisions and also communicate these problems to help mitigate downtime.

How does the SCADA System Work?

The SCADA system collects information such as, in areas where a leak has occurred in a pipeline and transfers this info back to the central control site. This alerts the control station that a leak has occurred and carried out all the necessary analysis as well as control through actions such as the determination of if the hole is critical, hence displaying the data in a logical and organized manner (Ruiz, Luis, Hugo & Romero 34). SCADA systems range from simple monitors of the environmental conditions of a small office building to a very complex system that monitors all the activities that are carried out in a nuclear power plant or even an entire operation of a water system in a municipality. These systems were introduced in the 1960s, and their use and technology have increased over the years (Kondratenko & Yuriy 445).

Basic SCADA Architecture

The underlying SCADA architecture is built on programmable logic controls (PLCs) or even the remote terminal units (RTUs). Both the RTUs and PLCs are microcomputers that are involved in the communication with numerous objects that including factory machinery installations, sensors HMIs, and end devices. The information that is gathered from these devices and objects is then routed to the main computers that have the SCADA software (Kondratenko & Yuriy 445). Therefore, the SCADA software helps in the processing, distribution as well as display of the data hence helping the operators as well as all other employees to be able to analyze the data and information collected to make critical decisions. For instance, the SCADA system can abruptly notify the operator that a section of the product is having a high incidence of errors. The person who receives this information is then able to pause the operation and view the SCADA system data through the utilization of the HMI to identify the cause of the problem. The operator can review the data that has been collected to discover the machine that is faulty in the production procedure. The ability of the SCADA system to notify the person operating the devices of the problem helps him or her to solve the issue as well as prevent any further loss of the product.

Figure 1 showing Basic SCADA Architecture (Internet Source)

Applications of SCADA Systems

SCADA systems are widely used in the modern world by various industrial organizations as well as companies in both the private and public sectors in controlling and maintaining efficiency, distribution of the collected data for smarter decisions, and communication of issues to help in solving the problems that arise. These systems are said to be the backbone of all modern industries such as energy, oil and gas, transportation, food and beverages, recycling, power, manufacturing, water, and sewerage (Ruiz, Luis, Hugo & Romero 99). It is important to note that in every setting of the modern world, there is some type of SCADA system that has been put into place to run behind the scenes as seen in, the maintenance of fridges and refrigeration systems in the supermarkets, helping in safety and production in a refinery point, managing a wastewater treatment plant to achieve the required quality standards and even in small scale use whereby individuals use the SCADA system to tract their energy uses at home. These are a few examples that are aimed at showing the full application of these systems that range from small-scale consumption to large industrial organizations (Li et al. 245). Therefore, the effective use of the SCADA by these entities leads to notable savings of money and time. Many case studies have been carried out and published that highlights the numerous benefits and savings that are achieved through the use of SCADA software solutions such as Ignition.

History and Origin of SCADA

SCADA systems were introduced to help in reducing the problems that were facing the industrial organizations in the 1960s. Before the introduction of the SCADA concept, numerous manufacturing floors, remote sites, and industrial plants all relied on the employees to manually control and also monitor equipment by analog dials and push-buttons (Ruiz et al. 432). The industrial floors and remote sites started to scale out of size, hence, solutions were needed to control these devices over long distances. This necessitated the use of relays and timers to provide supervisory control without necessarily sending personnel to remote locations to interact with each piece of equipment. These relays and timers were able to solve some of the problems as they provided some limited automation functionality. However, more problems started to come up as these relays and timers were difficult to configure and fault-find. Therefore, a more automated system of monitoring and control was needed which led to the development of SCADA in the 1960s which was the term used to refer to the first computers that were developed and used for industrial control purposes (Li et al. 367). Supervisory control started to become prevalent among the major utilities such as oil and gas pipelines, and other industrial markets that were operational at that time. In the mid-1960s, telemetry was developed for monitoring, which allowed for automated communications that we're able to transmit measurements as well as other data from the remotes sites to monitoring equipment (Kondratenko & Yuriy 565).

Figure 2 Early Devices That Gave Birth to the Modern SCADA Hardware (Internet Source)

The Evolution of SCADA

The first known recapitulation of the SCADA is said to have started as a mainframe computer. Networks that are used in the modern-day world were not available, hence, each SCADA system had to stand on its own as there were no connections. These initial systems have been referred to as monolithic SCADA systems (Kondratenko & Yuriy 565). In the 1990s to the early 2000s, designing upon the distributed system model, SCADA was able to adopt an incremental revolution by implementation and integration of open system architecture as well as improved communications protocols that were not vendor-specific (Kondratenko & Yuriy 565). This recapitulation of SCADA, now referred to as the networked SCADA system, took advantage of emerging and innovative communications technologies like the Ethernet. The Networked SCADA systems were able to allow systems from other vendors to communicate and form a network with each other. This innovation is one of the major earlier tools that were critical in lessening the limitations that were imposed by the older SCADA systems. This connectivity, therefore, allowed organizations and other entities to connect many devices to the network.

While SCADA systems have seen significant evolutionary changes and transformations, numerous industrial organizations continued to have problems with industrial data access from the enterprise level. However, by the late 1990s to mid-2000s, technological prosperity happened, and personal computing as well as IT technologies enhanced in development. Structured query language (SQL) databases then were able to become the standard for information technology databases but were not implemented by SCADA developers (Li et al. 468). This caused a rift between the fields of controls, information technology, and SCADA technology hence becoming antiquated over time. Traditional SCADA systems still use patented technology to handle and distribute data. Whether it is a data connector, data historian, or other means of data transfer, the solution is disordered and extremely costly. Modern SCADA systems are aimed at resolving this challenge by leveraging the most appropriate controls as well as IT technology.

Figure 3 Modern Day SCADA System (Internet Source)

Ignition SCADA Architecture

Figure 4 Ignition SCADA Architecture (Internet Source)

SCADA System Components

In general, the components of the SCADA system are centralized to control and monitor all computer operations. SCADA system components are software packages positioned adjacent to hardware. The supervisory system collects important data and transfers them to the commands control for processing. Remote terminal unit (RTU) that controls all automatic operations in a computer system. The RTUs are comprised of programmable logic converters that can be adjusted to a specific required level (Carcano et al., 178). The components of the SCADA system enable operators to control all activities in the computer system. The SCADA system is normally comprised of five main components that work together to ensure effective performances in a computer system. The SCADA system components include the following:

Supervisory Computers

Supervisory Computers is the main component of the SCADA system. This component collects data transfers control commands through connected devices to allow effective data processing. The supervisory computers comprise software that is assigned to monitor communication between the computer system and connection controllers. Supervisory computers control the operations of the remote terminal units and programmable logic units. In a modern SCADA system, HMI is incorporated in the supervisory computers, especially in the operator workstations (Fovinoet al., 12). In larger SCADA systems, the device is made up of multiple PCs, therefore, the connection contains many HMIs controlled by client computers. The use of client computers necessitates the use of multiple servers to promote the effective acquisition of data. Multiple servers also ensure that possible security threats and problems are minimized, therefore, reducing cyber-attacks and insecurities (Fovinoet al., 14). Being the core component of the SCADA system, the supervisory computer is a section that controls all important activities and regulates the scheduling of routine tasks, output/input operations, and actions that contribute to the detection and correction of errors. The supervisory computers component also regulates all tasks and routine operations of the data processing components.

Smaller SCADA systems contain fewer devices but they also operate to control the operations of the computer system. In the case of a smaller SCADA system, the supervisory computer is normally composed of a single Personal Computer (PC), therefore, the connection contains one HMI that ensures effective operations and monitoring tasks. It is not economical to use a client computer in the system because only one server is installed for data supply. The use of a single computer is important because it reduces cyber-attacks that might occur due to data-sharing. The inclusion of several servers also ensures the affective distribution of software application in the SCADA system and location sites used...