Chapter 7. Security

Table of Contents

Introduction
IT security in automation systems
Vulnerabilities and threats
Security versus reliability
Risk analyses and attack vectors
Hardening the Control System
Monitoring and managing security
Common IT security measures
Firewalls
Intrusion detection
Patching
Antivirus
Encryption and authentication techniques
IPsec
PKI
VPN
Wireless network security

Objective

After you have completed this chapter you should:

Introduction

Modern industrial control systems are implemented on commercial Information Technology (IT) platforms. The technical challenges that face the IT industry with regard to reliability and security are, therefore, also challenges encountered in control systems. Although the challenges may be similar in nature due to the common technological building blocks, there are fundamental differences between control systems and IT systems that require a different approach in the way that reliability and security is achieved and sustained.

It has become common practice to adopt security solutions from the IT industry in control systems without due consideration for technical merits or the appropriateness of those solutions. Elaborate or complex security systems may, in fact, degrade the reliability and performance of a control system. It is important that control systems are engineered and managed with reliability and security as a primary objective. In the fast majority of implementations, reliability and security can be achieved through a thorough understanding of the basics principles of IT security combined with good engineering practice in the design, implementation and management of those principles.