Mechanisms necessary to control the access of programs or users to the resources defined by a computer system

 

The goals of protection in an operating system are:

  •          To prevent malicious misuse of the system by users or programs
  •          To ensure each shared resource is used only in accordance with system policies
  •          To ensure errant programs cause the minimal amount of damage

To maximize security, programs, users and systems should be given just enough privileges to perform their tasks. This helps ensure failures will result in the least amount of harm done. An access matrix is a model of protection in which columns represent different system resources and rows represent protection domains. Cells within the matrix indicate what access that domain has to that resource.


References
Silberschatz, A., Galvin, P. B., & Gagne, G. (2014). Operating system concepts essentials (2nd ed.). Retrieved from https://redshelf.com/

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