Elementary Information Security, 3rd Edition

▶ 2.5 Keeping Processes Separate

Worms and other malware aren’t the only risks to computers. Operator errors and software bugs can pose as big a threat. Operating systems use access control mechanisms to keep processes separate.

Computing pioneers didn’t need computer-based access control mechanisms. In the 1940s and 1950s, users often had exclusive use of a computer while their programs were run. Access control relied on physical protection of the computer itself. Although computer users often shared the computer with others, they didn’t have to share space inside the computer with others. Each user brought along his or her own persistent storage to use while the program ran. Once a program was finished, a computer operator replaced one user’s ...