Industrial control system or ICS is widely used in various industries throughout the world. They are responsible for the examination, management, and administration of the whole industry ranging from robotics, nuclear power industries, to prison chamber doors.

ICS security mainly deals with the safety of industrial control systems as well as the associated devices, examination, and control of the machinery through the use of integrated hardware and software that are designed for this purpose.

Previously there were no networking and communication technologies to network the systems. Today, the main focus of the industrial IoT is to enable data interchange by the use of the internet. This is possible through the human-machine interfaces that are used for managing them.

But the major concern is that the ICS remains vulnerable to security threats because they can't be easily updated as they support critical infrastructure which needs 100% availability. Besides this, there are fewer resources in the systems for computing which leaves no scope for running anti-malware software.

Today when there is a greater risk due to the threat of cyber attacks, organizations have started devising ways to protect their ICS by devoting more resources. This is termed as ICS cyber security.

Sometimes, the organizations hesitate to update their systems as this would incur high costs, as well as the whole system, needs to be changed in order to comply with the industry regulations.

In order to protect these systems, SCADA(supervisory control and data acquisition) programs are needed. Also, such policies and processes need to be developed which can be implemented, modified as well as upgraded.

SCADA systems are necessary to control assets that are dispersed. They help in integration of the data acquisition systems with the data transmission systems and HMI software that enable a centralized monitoring of the various input and output processes.

The objectives that are fulfilled by the implementation of ICS cyber security are:

The logical access to the ICS network is restricted through various ways like use of DMZ network architecture with firewall (dematerialized zone), unidirectional gateways etc. Also, a multiple layersnetwork topology can be used for more security.

A restriction is imposed on physical access to the ICS network and related devices.

Security patches are deployed whenever necessary and the unused ports are disabled, the ICS user privileges are provided to specific persons, use of anti-virus and file integrity checking software etc. are used to ensure the protection of ICS components from being exploited.

The data in transit as well as in rest condition are protected from any kind of unauthorized access.

The detection of failed ICS components, services which are unavailable and the resources that have depleted are necessary to the functional safety of the ICS.

Ensuring functionality of ICS during unfavorable conditions by maintaining a redundant equivalent to ensure its uninterrupted functioning.

Provisions for quick recovery after any disaster.