Computer Science KS3 & 4 / GCSE: Problem Solved - Wifi Mesh

In this short film about Smart Cities and WiFi networks, BBC Radio 1 presenter Dev poses the question - “If a city wants to provide free high-speed WiFi access for visitors and residents, what would be the optimal placement of routers and network infrastructure over a specified area to get the maximum coverage and quality of service?”

To answer the question he investigates a Smart City and the ‘Bristol is Open’ project. It’s a great example of computational thinking – taking the problem, the ideal solution and all of the competing factors into account, to come up with the best fit solution.

Teachers Notes

The video shows how WiFi can be distributed across a city using a cable-free mesh structure. Pupils could compare this to designing a Network for a large and busy building, like a shopping mall. What are the key factors common to Urban and Domestic Networks?

Your class could use the data in the video to abstract and decompose the problem: what are the technical challenges we’d face if we were planning the network? Pupils could start with looking at how far Wi-Fi signals can transmit – about a hundred metres at best but the materials and density of the environment - like walls and buildings, and natural features like trees - can reduce that dramatically.

Next up pupils could consider where people will potentially want Wi-Fi access, so can they get data on urban use: where do people go? For example, what are the popular areas for shopping, having a coffee or lunch? This type of data will help to determine whether they need equal coverage and bandwidth across the entire city, or should pupils think about key "hot-spots"?

Curriculum Notes

This clip will be relevant for teaching Computer Science. This topic appears in OCR, Edexcel, AQA, WJEC KS4/GCSE in England and Wales, CCEA GCSE in Northern Ireland and SQA National 4/5 in Scotland.

More from the series Computer Science: Problem Solved

Creating secure messaging systems
Using 3D visualisation technology for online shopping
Using programming to find lost pets