Optical Fiber in the AI Era: Korea’s Position and Challenges Ahead

Demand from artificial intelligence (AI) data centers for submarine cables is expanding, and optical fiber is emerging as a core material of digital infrastructure; cable demand for AI applications rose 77 percent in 2025 over the previous year (CRU). South Korea leads the OECD in the share of fixed lines carried on optical cable, at 90.5 percent, yet its materials base is thin: only one domestic company produces preform, the stage at which value is concentrated. China, the United States, Japan, and India have each cultivated a domestic optical fiber industry, through subsidies and procurement preferences, domestic content requirements, state-funded research and development, and production linked incentives respectively, whereas Korea has no policy tailored to optical fiber materials. This study compares demand and price trends in the global optical fiber market, the competitiveness of the major producers, and policy at home and abroad, and on that basis sets out directions for developing Korea’s optical fiber materials industry: securing high-value preform manufacturing capability, developing next-generation fiber technologies such as multi-core fiber (MCF) and hollow-core fiber (HCF), and broadening the demand base through national infrastructure projects.