# Vox — The Hidden Network of Undersea Cables *A companion page to [Workshop 1 Hardware and Networks](/dt7/Workshop%201%20Hardware%20and%20Networks). Inspiration video referenced in the Workshop 1 booklet as `way2.cc/ca9`.* When you watched a YouTube video on a Raspberry Pi during Workshop 1, the data didn't arrive by magic and didn't really arrive by Wi-Fi either. Wi-Fi got the request from the Pi to the classroom router. After that, almost every byte travelled along a real, physical cable — and most of those cables sit on the ocean floor. Vox shows you the map. Around 99% of the world's internet traffic — every video call, every chat, every cloud save — runs through a network of submarine cables thinner than a garden hose. After this video, "the cloud" stops feeling abstract and starts feeling like a wet tangle of glass. --- ## The Video {{Video|src=https://www.youtube.com/watch?v=Ve810FHZ1CQ}} About 8 minutes. Vox covers the history (the very first transatlantic cable was 1858 telegraph wire), the modern build (cable ships, repeaters every ~50km, sharks biting fibre), and the geopolitics (who owns these cables, who can tap them). --- ## What to Watch For - **The thickness of a real submarine cable** — when they show one in cross-section, notice how thin the actual fibre strands are. Most of the cable is armour and insulation against fish, anchors, and seawater. - **Repeaters** — every ~50–100 km along a cable there's a small box that boosts the signal. Without them, the light pulse fades to nothing before crossing an ocean. - **The world map** — pause when they show the cable map. Notice how cables cluster: through the Strait of Malacca, around the UK, between the US and Europe. These chokepoints matter for politics and security. - **What happens when a cable breaks** — boats can find and lift the cable, splice it, drop it back. Wild engineering. - **Why "cloud" is a funny word** — almost nothing about the internet is actually wireless once it leaves your local network. The metaphor is misleading. --- ## <i class="fas fa-lightbulb"></i> Have a Go ::: info **<i class="fas fa-pencil-alt"></i> Your turn!** Grab a pen and have a crack at these. ::: **<i class="fas fa-film"></i> Question** ① — In your own words, why do submarine cables need repeaters every 50–100 km? **<i class="fas fa-globe-asia"></i> Question** ② — Look at a world map (or the one in the video). If you sent a message from Hamilton, VIC to a friend in London, list the major bodies of water it would probably cross under. ::: tip ⚡ **Hint:** It depends on the cable route — some go via the Pacific and the US, others via the Indian Ocean and the Mediterranean. ::: **<i class="fas fa-shield-halved"></i> Question** ③ — Why does Vox say undersea cables matter for *politics* and *security*, not just engineering? Give one specific example from the video. **<i class="fas fa-cloud"></i> Question** ④ — When someone says they "stored their photo in the cloud", they usually mean they saved it to a server in another country. Trace the rough physical journey of one photo from your phone to a Google data centre. (Wi-Fi → router → ISP → … → cable → … → data centre.) --- See also: [Workshop 1 Hardware and Networks](/dt7/Workshop%201%20Hardware%20and%20Networks) · [Tom Scott - Fetch Execute Cycle](/dt7/Tom%20Scott%20-%20Fetch%20Execute%20Cycle) · [Crash Course - Binary](/dt7/Crash%20Course%20-%20Binary) *Last updated: April 2026.* ← Back to [Year 7 Hub](/dt7/Year%207%20Hub)