<P> The US Department of Homeland Security National Cyber Security Division (NCSD) operates the Control System Security Program (CSSP). The program operates a specialized computer emergency response team called the Industrial Control Systems Cyber Emergency Response Team (ICS - CERT), conducts a biannual conference (ICSJWG), provides training, publishes recommended practices, and provides a self - assessment tool . As part of a Department of Homeland Security plan to improve American computer security, in 2008 it and the Idaho National Laboratory (INL) worked with Siemens to identify security holes in the company's widely used Process Control System 7 (PCS 7) and its software Step 7 . In July 2008, INL and Siemens publicly announced flaws in the control system at a Chicago conference; Stuxnet exploited these holes in 2009 . </P> <P> Several industry organizations and professional societies have published standards and best practice guidelines providing direction and guidance for control system end - users on how to establish a control system security management program . The basic premise that all of these documents share is that prevention requires a multi-layered approach, often referred to as "defense - in - depth". The layers include policies and procedures, awareness and training, network segmentation, access control measures, physical security measures, system hardening, e.g., patch management, and system monitoring, anti-virus and intrusion prevention system (IPS). The standards and best practices also all recommend starting with a risk analysis and a control system security assessment . </P> <Table> <Tr> <Td> </Td> <Td> This section needs to be updated . Please update this article to reflect recent events or newly available information . (December 2017) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This section needs to be updated . Please update this article to reflect recent events or newly available information . (December 2017) </Td> </Tr>

How was the stuxnet virus developed and how did it find its target