Connecting Three Buildings at a Rural School
A rural secondary school has three buildings 80 m apart: administration, two classroom blocks, and a library. It has one 10 Mbps fibre link and a 4G backup router with a 20 GB monthly cap. There are 90 learners and 12 teachers. The school wants every classroom to use an online learning platform, but currently one consumer Wi-Fi router in the administration block provides weak coverage. Teachers report video lessons stall, while the administration office says the cashier's cloud backups saturate the link at month-end. The school has 45 tablets, 20 laptops, 12 desktop PCs, and a networked printer. The budget allows either cabling two buildings or buying six mesh Wi-Fi nodes. There is no network administrator. The school day runs 07:30 to 16:00, and examinations require reliable access to a local question bank stored on one desktop.
1. Recommend a network design and justify whether the school should choose cabling or mesh Wi-Fi nodes.
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Choose a hybrid wired-first design, not six mesh nodes alone. Mesh is quick to install, but each node repeats traffic over the same crowded 2.4 or 5 GHz channels; with 77 devices and weak signal, video and examination traffic will compete. Run fibre or outdoor Cat6 from the administration building to the two classroom blocks, and use a small switch and one access point per classroom. Keep the library either on the wired backbone or on one mesh node with a wired backhaul. Place the local question bank on a wired server or desktop in administration, not on Wi-Fi, and give examination rooms a wired drop or a dedicated access point. If the 80 m path exceeds copper's 100 m limit after routing, use fibre. The no-administrator constraint favours labelled, managed switches with a simple documented plan rather than many consumer nodes.
2. Propose traffic-management and backup rules that keep the 10 Mbps link usable and protect the 20 GB 4G cap.
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Separate traffic into at least three VLANs or SSIDs: staff, learners, and administration. Put the cloud backup and printer on the administration VLAN, apply quality-of-service rules so examination traffic gets priority, and cap learner video to 480p. Cache learning-platform content on a local server so repeated lessons do not consume the 10 Mbps link. Schedule cashier backups after 16:00 and throttle them; disable automatic cloud sync during school hours. Treat the 4G router as failover only, with a 20 GB cap: block video and large downloads on it, and alert when 15 GB is used. For examinations, disconnect learner internet and serve the question bank locally over the wired LAN. These controls fit the small budget and reduce dependence on an administrator.