Implementation of a Defense in Depth Strategy to Protect Critical Infrastructure Industrial Control Systems

Abstract

The goal of this communication is to examine the implementation of defense in depth strategy to secure the industrialcontrol systems (ICS) from threats, hackers, vandals and other ones that can damage the critical infrastructures (gas transportationnetwork, power transmission network, power generation, power distribution grids, air traffic, petrochemical industries, rail traffic,military industries) and others big infrastructures that affect large number of persons and security of nations [1]. The defense in depthconcept ensures the physical access protection of the infrastructure, using network access control system (NAC) and traditionalsecurity measures, and implements policies and procedures that deal training and cybersecurity awareness programs, risk assessment(analyzing and documenting), and the plan of security. The philosophy of defense in depth uses also the IT technologies in order toensure separation and segmentations of the networks to the VLANs, demilitarized zones, VPN, using firewalls, switch and routers.The hardening of different systems installed like routers, firewalls, switches and other devices on the network such as SCADA serversis a very sensitive operation of defense in depth.