Exposure to external attacks

Critical infrastructure networks are increasingly using Internet protocols and communicate with external resources, sometimes over the public Internet. The transition into Internet Protocol (IP) based networks helps reduce costs and improve efficiency, but it also exposes these previously isolated networks to external attacks. Most systems and protocols used in critical infrastructure networks were developed for closed networks with trusted devices and no connection to the outside world. They contain very little security features, and more worryingly, they have never been hardened. The biggest threat are devices, such as programmable logic controllers (PLCs) that control physical equipment like pumps and valves.  When connecting industrial control networks to corporate networks and introducing other forms of connectivity, it is important to understand what the risks are and perform the necessary actions to mitigate the risks.