An operating system manages the users of a computer.
Describe how an operating system checks that a user is allowed to log in.
Mark scheme
Award up to two marks for a linked description such as:
- The user enters a username/user ID and password/PIN (1) which is compared with the account details the operating system has stored (1)
- The operating system keeps a file/list/database of users and their passwords (1) to check the login details the user enters against (1)
- The operating system compares the entered details with the details stored for that user (1) and if they do not match, access is refused/denied (1)
- The entered details are checked against the access rights stored for that user (1) so access is only allowed when the details are correct (1)
Do not award for 'it asks for a password' on its own, without saying what the password is checked against.
A stored list/file of users and passwords with no check of the login details earns one mark only.
Do not accept responses about file management, such as finding or opening the user's files.
Example answers and how they were marked
The user types in a username and password. The operating system compares these with the details it has stored for that account, and if they match the user is allowed to log in.
Why: Username and password entered (1) which is compared with the account details the operating system has stored (1).
The operating system has a list of all the users and their passwords.
Why: The stored list of users and passwords (1), but no check of the login details against it, so the development mark is not earned (0); the mark scheme states a list alone earns one mark only.
The operating system finds the user's files on the hard drive and opens the last one they saved.
Why: Describes file management, not checking a user's login details; the mark scheme says not to accept responses about file management, so there is no creditworthy point.