A message has to get from one computer to another. Your job is to send it, then read it at the other end.
One concept only: things are wrapped in order to travel, and unwrapped in reverse order to be read. No score, no timer, no levels.
Run it: Work through the wrapping together on the projector, then stop before unwrapping and have the class predict the order.
Ask: "We added the layers app, transport, network, link. What order do we take them off in to read the message, and why that order?"
Watch for: Students unwrapping in the same order they wrapped. The reverse order is the point. Reinforce the PDU names (data, segment, packet, frame), which is the examinable vocabulary.
Clicked has interactives like this for subnetting, the TCP handshake, DNS, and more. One classroom, one subscription.
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