Describe what is meant by a virtual machine. Include in your answer two benefits and two drawbacks of using a virtual machine.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2022). The mark or mark type is shown in brackets.

1. [1] (a) One mark for each description (Max 2) • The emulation of a computer system / hardware and/or software
2. [1] (a) • ... using a host computer system.
3. [1] (a) • Using guest operating system(s) for emulation.
4. [1] (a) One mark for each correct benefit (Max 2) • Multiple guest operating systems / VMs can be used on the same computer.
5. [1] (a) • Different instruction set architectures can be emulated on a single computer.
6. [1] (a) • A virtual machine can crash without affecting the host machine.
7. [1] (a) • There are security benefits // Trying a piece of suspicious software and if it is / has a virus, it will only infect the virtual machine.
8. [1] (a) • Cost savings due to not needing to purchase extra hardware.
9. [1] (a) • Can run legacy applications that are currently incompatible.
10. [1] (a) One mark for each correct drawback (Max 2) • A virtual machine is less efficient / poorer performance than real machines because of extra load on the host computer
11. [1] (a) • Performance of the guest system cannot be adequately measured.
12. [1] (a) • A virtual machine may be affected by any weaknesses of the host machine.
13. [1] (a) • Costly and/or complex to maintain / implement / manage.
14. [1] (a) • Cannot emulate some hardware.