Site networking – from company headquarters to field station
The operators of critical infrastructures must meet very stringent demands on their network's speed, reliability and security: Systems are usually distributed locally and can even be operated "unmanned" in public areas – it is therefore indispensable to have powerful and secure site networking. The demands for secure network connection differ greatly, especially with regard to network access (directional radio, satellite transmission, dark fibre, leased lines or mobile/DSL/dedicated lines), data throughput or environmental requirements.
The threat posed to IT networks in CRITIS is high – the networks and systems to be controlled, such as power plants, wind farms and pumping stations, in which industrial control systems are operated, can usually span across several sites and a number of distributed field stations. Besides eavesdropping protection, a decisive role is also played by anti-manipulation protection, data line availability, as well as secure connection to the centralised control centres and control systems of field stations and equipment. In such critical networks, activities such as eavesdropping, manipulating the control commands to be transmitted, or disconnecting the remotely controlled systems, which are responsible for the central control points, from the network are equivalent to a digital meltdown.
The German Federal Office for Information Security (BSI) has evaluated technologies for site networking in the study "Sicherheitseigenschaften von Standleitungstechnologien" (Security Characteristics of Dedicated Line Technologies) and recommends using encryption technologies, whenever possible, for increased protection requirements.