Operating Systems

Operating systems (OS) are the most fundamental elements of digital security. Understanding them is central to any basic knowledge of infosec. Proper basic knowledge of OS can be found in books by Andrew Tanenbaum and Herbert Bos.

An OS manages:

• application programs and their data
• file systems and storage
• input and output
  • network connections
  • peripheral devices

The OS governs all four fundamental functions of a computer, storage, computation, communication and control.

Relevant to the subject of computer security, today there are two broad classes of OS; deterministic and non-deterministic which should be treated entirely differently.