SCADA Telecommunications and infrastructure
In the first stage, SCADA systems use modern communications and a combination of direct and serial radio communication to meet communication needs.
Of course, IP and Ethernet over SONET / SDH can also be used in large locations such as power plants and railway stations.
The function of remote monitoring and management of a SCADA system is called telemetry.
SCADA protocols are designed to be highly compact and send information to the master station only when the RTU is selected by the master station.
In general, the types of protocols used in SCADA networks are: Profibus, Modbus, RP-570 and Conitel. These communication protocols are for the builders of SCADA systems.
Standard protocols include IEC 61850 and DNP3 and IEC 60870-5-101.
These standard protocols have been identified and standardized by the major manufacturers of SCADA.
Many of these protocols have been extended to operate in TCP / IP.
The development of many automatic control devices and RTUs dates back to before the advent of industry standards for internal performance.
For this reason, PLE has been widely accepted as a solution in process control applications for effective and efficient communication between different software and hardware.
PLE allows the transfer of information between devices that are not originally part of the industrial network.
Scada Architecture
The SCADA system has various architectures that have evolved over time.
Monolithic architecture
Integrated Architecture is the first generation of architecture in SCADA systems.
In this architecture, mainframes were used to perform calculations.
When early SCADA systems were developed, Internet networks did not yet exist.
Therefore, the first generation SCADA systems have no connection with other systems and are therefore considered independent systems.
Over time, RTU makers developed WANs that were effective in communicating with RTUs.
The use of protocols was specific at the time. If the mainframe failed in the system or there was a problem with its operation, there was a backup mainframe that connected to the bus.
Distributed architecture
Distributed architecture is the second generation of SCADA systems. In this architecture, information is shared between different stations in real time via LAN, thus distributing the process between several different stations. The price and size of stations in this generation were greatly reduced compared to the first generation stations. But the protocols used in this network were still proprietary and caused many security problems for SCADA systems. Due to the specificity of the protocols, very few people know how secure the installation of the SCADA system has been.
Networked architecture
The third generation network architecture is considered to be SCADA systems. The SCAD systems used today belong to this category. Communication between the system and the master station is done through WAN protocols such as Internet Protocols (IP). In SCADA network architecture, because standard protocols are used and the system is accessible via the Internet, the system vulnerability is greatly increased.
However, the use of security techniques and standard protocol tools to improve security can also be applied to SCADA systems.
SCADA Part 4: SCADA Network Hardware Architecture
SCADA Part 3: SCADA Telecommunications and infrastructure
SCADA Part 2: SCADA system hardware
SCADA Part 1: The concept of the SCADA system
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