#10 Jun 2024 Q2(c)(iii) 3 marks 1.3.1 switch operation

Question

Lead-in: An airport has a LAN. One office has five computers connected to one switch. The computers are connected using a star topology.

(c)(iii) Describe the role of the switch in the star topology.

[3]

Why this question is tricky

A common misconception was that a switch performed the same role as a server, with candidates incorrectly identifying that the switch stored the data for devices in the network and that the switch provided services to the connected devices.— J277_01_ER_Jun2024.txt lines 210-213

MS complexity 2/10: Low structural complexity but a deep, well-documented role confusion across network devices.

Full-marks model answer

A switch connects the devices together in the star network so they can communicate with each other.

The switch stores the MAC addresses of all the devices connected to it in a table.

When the switch receives a data packet it uses the destination MAC address to direct the data only to the correct device.

Mark allocation (3 marks)
  • MP1: "Connects the devices together in the network // allows devices to communicate".
  • MP2: "Records/stores the address of devices connected to it... in a table / Uses MAC addresses".
  • MP3: "Directs data to destination / ...if address not recorded, transmits to all devices".

Watch out for...

A switch is not a server. It does not store user data or provide services. It stores MAC addresses in a lookup table and forwards packets only to the correct device. Don't say "the switch stores data" — say "stores MAC addresses".