The increasing interconnectivity of SCADA (Supervisory Control and Data Acquisition)
networks has exposed them to a wide range of network security problems. This paper
provides an overview of all the crucial research issues that are involved in strengthening
the cyber security of SCADA networks. The paper describes the general architecture of
SCADA networks and the properties of some of the commonly used SCADA communication
protocols. The general security threats and vulnerabilities in these networks are
discussed followed by a survey of the research challenges facing SCADA networks. The
paper discusses the ongoing work in several SCADA security areas such as improving
access control, firewalls and intrusion detection systems, SCADA protocol analyses,
cryptography and key management, device and operating system security. Many trade
and research organizations are involved in trying to standardize SCADA security technologies.
The paper concludes with an overview of these standardization efforts.