How They Made the Internet Cables Under the Ocean

3-Second Blueprint (English)

1. Transoceanic cables carry bidirectional laser data through paired glass fibers encased in jelly, copper, aluminum, steel, and plastic.
2. Because light attenuates across thousands of kilometers, powered optical repeaters are spliced inline to amplify signals along the seabed.
3. Deep-sea cable measures roughly one inch thick, whereas shallow coastal runs are heavily armored and buried against anchors and trawlers.