Security in Computing, Third Edition

5.4. Trusted Operating System Design

Operating systems by themselves (regardless of their security constraints) are very difficult to design. They handle many duties, are subject to interruptions and context switches, and must minimize overhead so as not to slow user computations and interactions. Adding the responsibility for security enforcement to the operating system substantially increases the difficulty of designing an operating system.

Nevertheless, the need for effective security is becoming more pervasive, and good software engineering principles tell us that it is better to design the security in at the beginning than to shoehorn it in at the end. (See Sidebar 5-3 for more about good design principles.) Thus, this section focuses on ...