Industrial Control System – Network Components
There are different network characteristics for each layer within a control system hierarchy. Network topologies across different ICS (Industrial Control System), implementations vary with modern systems using Internet-based IT and enterprise integration strategies.
Control networks have merged with corporate networks to allow control engineers to monitor and control systems from outside of the control system network. The connection may also allow enterprise-level decision-makers to obtain access to process data.
The following is a list of the major components of an ICS (Industrial Control System) network, regardless of the network topologies in use:
- Fieldbus Network. The fieldbus network links sensors and other devices to a PLC (Programmable Logic Controllers) or other controller. Use of fieldbus technologies eliminates the need for point-to-point wiring between the controller and each device. The sensors communicate with the fieldbus controller using a specific protocol. The messages sent between the sensors and the controller uniquely identify each of the sensors.
- Control Network. The control network connects the supervisory control level to lower-level control modules.
- Communications Routers. A router is a communications device that transfers messages between two networks. Common uses for routers include connecting a LAN (local area network) to a WAN (wide area network), and connecting MTUs (Master Terminal Units ) and RTUs (Remote Terminal Units) to a long-distance network medium for SCADA (Supervisory Control and Data Acquisition) communication.
- Firewall. A firewall protects devices on a network by monitoring and controlling communication packets using predefined filtering policies. Firewalls are also useful in managing ICS network segregation strategies.
- Modems. A modem is a device used to convert between serial digital data and a signal suitable for transmission over a telephone line to allow devices to communicate. Modems are often used in SCADA (Supervisory Control and Data Acquisition) systems to enable long-distance serial communications between master terminal units and remote field devices.
They are also used in Supervisory Control and Data Acquisition systems, Distributed Control Systems (DCS), and Programmable Logic Controllers (PLCs) for gaining remote access for operational and maintenance functions such as entering commands or modifying parameters, and diagnostic purposes. - Remote Access Points. Remote access points are distinct devices, areas and locations of a control network for remotely configuring control systems and accessing process data. Examples include using a personal digital assistant (PDA) to access data over a LAN through a wireless access point, and using a laptop and modem connection to remotely access an Industrial Control System (ICS).
12 Responses to “Industrial Control System – Network Components”
What is IEC 870 ?
IEC 870 Telecontrol equipment and systems is a standard developed by the International Electrotechnical Commission.
What is DNP3 ?
DNP3 (Distributed Network Protocol Version 3.0) is an open protocol developed by Harris Controls Division, Distributed Automation Products in the early 1990s and released to the industry based DNP3 Users Group in November 1993.
Who support DNP3 ?
The Distributed Network Protocol Version 3.0 (DNP3).is supported by a large
number of vendors and users in electrical, water infrastructure, and other industries in North America, South America, South Africa, Asia, Australia and New Zealand.
In Europe is used usually IEC 60870-5 ?
What is the key feature of DNP3 ?
It is an open protocol standard.
Why where developed DNP3 and IEC 60870-5 ?
There were develped specifically for SCADA (supervisory control and data acquisition) applications.
What are the key features of DNP3 and IEC 60870-5 ?
1)Open protocols, available for use by any manufacturer or user
2)Designed for reliable communication of data and control
3)Widely supported by manufacturers of SCADA master systems and software,
and of RTUs and IEDs
interesting post
a very good article about Industrial Control System – Network Components