Edexcel GCSE Computer Science (1CP2) Exam Questions

Award up to two marks for a linked description such as:

• Gives each process a share/a small amount (time slice) of the CPU time (1) so that several processes can run and appear to run at the same time (1)
• Decides which process will use the CPU next, e.g. by priority (1) so that the most important process is run first (1)
• Keeps track of the state of each process (ready/running/blocked) (1) so that each process is moved to the state it needs to be in (1)
• Moves a process that is waiting for input/a resource (e.g. a printer) to blocked (1) so that another process can use the CPU (1)

Do not award a mark for stating only that the operating system runs/controls the programs.

Do not award a mark for describing multitasking in general, e.g. 'the operating system runs more than one program at once', without saying how the operating system manages the processes.

Do not accept responses about memory management (e.g. loading a program into RAM), the user interface or user management.

Accept 'processor' for CPU.

Indicative content

User accounts

• Each student and teacher should have their own user account, so the operating system can identify the person who is logged on.
• The operating system keeps a record of all valid users on the computer, so unknown users are not allowed to log in.
• A separate home area or folder can be created for each account, so a student's saved work is kept apart from other users' work.
• An account can be disabled when a student leaves the school, so they can no longer access the computers.

Authentication

• A username and password can be required at login, so only users with the correct details can use the computer.
• The operating system checks the entered password against the stored password for that account before allowing access.
• Users should be encouraged to choose a strong password, which makes it harder for someone else to guess and log in.
• The operating system can lock an account after several failed login attempts, which reduces the chance of someone trying passwords repeatedly.

Benefits for the school

• Many students can share the same computers because each person's files are kept separate.
• Work is less likely to be deleted or changed by another student, because users only see their own files.
• The school can see which account was used on a computer, so misuse can be traced to a user.
• Teachers can be confident that only authorised people can use the library computers.
• The school does not need a separate computer for every student, so it saves money.

Levels

• Level 0 (0 marks): No rewardable content.
• Level 1 (1–2 marks): Basic, independent points are made, showing elements of understanding of key concepts/principles of computer science. (AO1) The discussion will contain basic information with little linkage between points made or application to the context. (AO2)
• Level 2 (3–4 marks): Demonstrates adequate understanding of key concepts/principles of computer science. (AO1) The discussion shows some linkages and lines of reasoning with some structure and application to the context. (AO2)
• Level 3 (5–6 marks): Demonstrates comprehensive understanding of key concepts/principles of computer science to support the discussion being presented. (AO1) The discussion is well developed, with sustained lines of reasoning that are coherent and logically structured, and which clearly apply to the context. (AO2)

Level 3 responses must cover both user accounts and authentication, and apply them to the school library.

Do not accept general operating system functions such as file management or process management unless they are explicitly linked to managing users.