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AI supply chain term

Subsea cable

A subsea cable is an undersea fiber-optic line laid across the ocean floor to carry data between continents — the physical backbone for the overwhelming majority of international internet traffic.

What it means

Subsea, or submarine, cables are bundles of optical fibers, armored and powered by inline repeaters, that run for thousands of kilometers along the seabed to link continents. They carry almost all intercontinental data, so cross-region AI serving, data replication and sovereign-cloud strategies all ultimately ride this thin physical layer. Each cable takes years to plan and lay, involves a handful of specialized ships and suppliers, and can take weeks to repair when damaged by anchors, fishing gear or geopolitics. In the AI supply chain it sits at the far edge of the interconnect layer, setting the ceiling on how much data can move between world regions. It is a constraint because capacity, routes and repair capacity are limited and slow to add; it is a lever for whoever owns and operates the routes.

Why it matters to investors

Subsea capacity is the slow-moving physical limit on cross-border AI traffic, and only a few suppliers can build and lay it. System integrators such as Nokia (NOK) and Ciena (CIEN), plus fiber and cable makers Corning (GLW) and Hengtong Optic-Electric (600487.SH), are the exposed names along this layer.

See Subsea cable in the AI value chainIts live model score, why it matters, and every company exposed to it.

Companies on this part of the chain

Nokia CorporationNOKCienaCIENCorning IncorporatedGLWHengtong Optic-Electric Co., Ltd.600487.SH

Named to show where the term sits in the AI supply chain — research, not advice, and never a recommendation to buy or sell.

Related terms

DWDMDWDM (dense wavelength-division multiplexing) is a technique that sends many separate data streams down one optical fiber at once, each carried on a slightly different wavelength, or color, of light.Optical transceiver / photonicsA module that converts electrical signals to light (and back) for optical links.Sovereign AISovereign AI is the effort by governments to buy and build their own AI supercomputers and national AI clouds so that compute, data and models stay under domestic control.

See Subsea cable in the live AI chain.

THE ENTITY maps every constraint onto one live model — which part is tight now, who owns it, and who gets squeezed when it moves. Plain-English reads you can check.

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THE ENTITY is an educational read on the AI supply chain — research, not investment advice. It explains how the chain works and who sits where, never price targets or buy/sell calls.