1.6 Security and Protection Flashcards
If a computer system has multiple users, access to data must be regulated by __________.
mechanisms
Memory-addressing hardware ensures that a process can execute only within its own __________.
address space
The __________ ensures that no process can gain control of the CPU without eventually relinquishing control.
timer
Device-control registers are not accessible to __________.
users
Protection is any mechanism for controlling the access of processes or users to the __________ defined by a computer system.
resources
Protection mechanisms must provide means to specify the controls to be imposed and to __________ the controls.
enforce
Protection can improve reliability by detecting latent errors at the __________ between component subsystems.
interfaces
An unprotected resource cannot defend against use or misuse by an __________ or incompetent user.
unauthorized
A protection-oriented system provides a means to distinguish between authorized and __________ usage.
unauthorized
Security is responsible for defending a system from external and internal __________.
attacks
Denial-of-service attacks use all of a system’s resources and keep legitimate users __________.
out of the system
Operating system security features are a fast-growing area of __________ and implementation.
research
Most operating systems maintain a list of user names and associated __________.
user identifiers (user IDs)
In Windows, the user identifier is known as a security __________.
ID (SID)
When a user logs in to the system, the authentication stage determines the appropriate __________ for the user.
user ID
To distinguish among sets of users, we need to define a __________ name and the set of users belonging to that group.
group
Group functionality can be implemented as a system-wide list of __________ names and group identifiers.
group
A user can be in one or more __________, depending on operating-system design decisions.
groups
A user sometimes needs to escalate __________ to gain extra permissions for an activity.
privileges
On UNIX, the setuid attribute on a program causes that program to run with the user ID of the __________ of the file.
owner
The process runs with this effective UID until it turns off the extra privileges or __________.
terminates
