File Storage – local disk, server or the cloud
Computer ScienceFiles, Storage & DatabasesAges 16–17
Use it with your class: students open it from a link or a QR code, with no account needed.
Next in Files, Storage & Databases
The same file is kept in three places: a personal computer's disk, a school server, or a cloud storage service. Students click each device to edit the file (bumping its version number), click Sync to watch the data travel over the network with a time equal to file size times 8 divided by network speed, then pick a scenario — lost connection, a failed hard drive, or two devices editing at once — to see which storage option survives the incident and which one loses data.
Lesson: Online storage and cloud computing: sync, sharing, versioning and data safety
What it shows
The model follows one file shared by up to five devices and kept on a personal computer's disk, a school server or a cloud storage service. Each edit raises the version number on that device, and syncing sends the newest version over the network. Because one byte is eight bits, transfer time in seconds equals size in MB × 8 ÷ speed in Mbps. Incident scenarios expose the trade-offs of each option: access without a network, a single point of failure, and version conflicts when two people edit at once.
How to use
Start in the Normal scenario with the cloud storage service selected. Click a device to edit the file, press Sync and check the time shown against the File size and Network speed you chose. Then change Where the file is stored and run each Scenario in turn. Before revealing results, ask students to predict which option loses data or creates a conflict, and use Share with a Friend to compare how each option handles sharing.
Parameters you can change
- Where the file is stored Personal computer disk, School server, Cloud storage service
- Number of devices sharing the file 1–5 devices
- File size 1–2000 MB
- Network speed 1–1000 Mbps
- Scenario Normal, Network connection lost, Personal hard drive fails, Two devices edit at once
Questions to explore
- How long does a 250 MB file take to sync over a 50 Mbps connection, and what changes if you double the speed?
- Which storage option still lets you open and edit the file when the network connection is lost?
- What happens to the file versions when two devices edit at once and then sync with the cloud?
