A farm uses wired connections to link sensors in its fields to a computer in the farmhouse.
Describe how the range of a wired connection can affect the performance of this network.
Mark scheme
Award up to two marks for a linked description such as:
- (Twisted pair/copper) cable only carries data over a limited distance (about 100 metres) (1) so sensors further away need another switch/device to pass the data on to the farmhouse (1)
- Fibre optic cable can carry data over much longer distances (1) so wired connections can reach sensors across the whole farm (1)
- Data sent further than the cable's range is not received (1) so the computer in the farmhouse does not get readings from those sensors (1)
- A wireless connection can reach sensors that are out of range of the cables (1) so a mix of the two can give readings across the whole site (1)
Allow responses about signal weakening/being lost over a long cable.
Do not accept responses about bandwidth or speed, as range is about distance, not the amount or rate of data.
Example answers and how they were marked
Twisted pair copper cable only carries data for about 100 metres (1) so a switch is needed in each field to pass the readings on to the farmhouse (1).
Why: Point that copper cable has a limited distance (1) linked to needing another device to extend the network (1).
Fibre optic cable can carry data much further than copper cable.
Why: Gives the first point of a linked pair (1) but does not develop it to say what this allows the farm to do.
A longer cable gives the network a bigger bandwidth so the sensors work faster.
Why: About bandwidth and speed rather than range, which the mark scheme says is not accepted.