AI data centers consume far more fiber than legacy designs

Tom's Hardware reports that AI-focused data center construction is creating fiber demand that supply chains cannot currently match. The article reports major Chinese manufacturers have booked orders into early 2027 and that delivery cycles for some cable products have stretched from weeks to months, per conversations the outlet attributes to industry sources. Tom's Hardware cites CRU data that data center fiber demand grew roughly 76% year-on-year in 2025, and that the data-center segment is projected to account for 30% of global fiber demand by 2027, up from below 5% in 2024.

Tom's Hardware cites reporting that the higher fiber intensity for AI clusters stems from much denser interconnect fabrics; the article references Rahul Puri, CEO of STL's Optical Networking Business, as telling Fierce Network in December that AI-focused data centers require approximately 36 times more fiber than traditional CPU-server racks. The piece also highlights a manufacturing constraint: the production of optical-fiber preforms, the glass rods from which fiber is drawn, is technically demanding and has high barriers to entry. Tom's Hardware cites DigiTimes reporting that new preform capacity typically takes 18 to 24 months to build, which limits near-term supply even if downstream cable drawing could scale faster.

Editorial analysis - technical context: The combination of a large multiplier in per-rack fiber use and long lead times for preform capacity creates a structural lag between demand and the earliest feasible supply expansion. Industry-pattern observations: suppliers often run existing draw lines at full utilization before new preform lines come online, which shifts bottlenecks upstream to specialty glass and preform manufacturing rather than to cable assembly alone.

For practitioners: monitor announced preform-factory capacity expansions, procurement lead times from major suppliers (reported bookings into 2027), and design changes that reduce fiber counts per rack. Observers should also track alternative interconnect approaches and supplier diversification signals from hyperscalers and major telcos, since those are the levers that historically reduce concentration risk in optical supply chains.