Prepaid fiber orders make 2027-28 demand a stronger signal than capex plans. Corning reports $639M in net customer deposits in the first nine months and expects data-center interconnect to beat its former $1B-by-2030 target on timing and size. That backs Lumen's intercity build, though its next allocation may require a bigger commitment. Tight Corning supply gives Amphenol room to gain share until capacity expands; strong demand alone has not lifted stocks across the chain. x.com 

Higher optical-fiber use per GPU could expand demand for Applied Optoelectronics. Corning said fully optical scale-up would raise fiber count from about 16 to 160 per GPU; that 10x case is hypothetical for now, with a mix of technologies likely near term, but it shows the direction of travel. x.com  x.com 

Furukawa Electric is not worth chasing because companies like it will fail to raise prices on high-demand products and stay committed to low-margin, low-growth segments. This is not a rejection of growth. A post in the thread notes that end customers such as Nvidia and Micron earn 75% gross margins, yet Japanese suppliers prefer to let Americans take the margin. x.com 

Rising 1.6T switching demand favors optical suppliers, though their execution risks vary. Bank of America says the market could grow ~101% annually through 2030. Marvell's leading DSPs and Lumentum's supply-short 200G EML lasers are lowest risk; Applied Optoelectronics' capacity expansion and Fabrinet's customer concentration make them medium risk. Aeluma remains pre-commercial, while Lightwave Logic's polymer modulators are a high-risk moonshot despite its TSM partnership. x.com 

Undersea cables and scale-across are very bullish, though the two biggest builders, Alcatel and SubCom, are private. Public plays span the chain: fiber from Corning, Sumitomo and Furukawa, where subsea is a small share of revenue; cable supplier Prysmian, mostly a power-cable name; 980nm pump lasers, where Lumentum and Coherent hold a duopoly and Lumentum guided to 4x volume next year; onshore gear from Ciena, with 60% share ex-China, and Nokia; and integrator NEC. x.com 

Optical networking's broader rollout will be slow because scale-up and scale-out require orders of magnitude more connections than today's limited optical distance links. Supply-chain discussions echo that slow pace. NPO/CPO starts in switches and reaches XPUs and GPUs much later, with new challenges. Optical backplanes will be necessary as racks move to optical, though copper will remain in many implementations. x.com  x.com  x.com  x.com 

Corning now has long-term fiber deals with both Verizon and AT&T, supplying both broadband expansion and links between AI data centers. AT&T announced a multiyear fiber and cable deal exceeding $3B focused on home and business broadband, following Verizon's multibillion-dollar deal for over 80 million fiber miles from 2027 to 2032, including long-haul AI data center links. These deals could improve demand visibility; watch shipment ramps and profit growth versus expansion costs. x.com 

Telecom fiber providers Ciena and Nokia stand to benefit because AI will need far more data-center interconnect, as another investor's post illustrated. x.com 

Optical transceiver demand exceeds supply, and 1.6T lifts revenue per module for suppliers able to qualify capacity. Applied Optoelectronics raised at least $1.62B through 2026 ATMs; its last reported monthly capacity was 200,000 modules versus a year-end target above 650,000. Credo expects over $600M in FY2027 revenue across optical DSPs, PICs and modules, not modules alone. Shipments, yields and margins must prove out. Lumentum and Coherent already price in much expected growth. x.com 

Fabrinet is the strategic bottleneck for 1.6T optical interconnects, as its proprietary 5-axis active alignment solves the sub-0.5-micron laser coupling these transceivers need. HPC revenue jumped to $86M in Q2 FY26 from $15M on 200G EML lasers for Nvidia networking. Its Thailand Building 10 expansion starts going live in July 2026, AWS and Google broaden the customer base, and it holds $961M cash with no net debt. At about 3.6x forward sales, it is not priced for hype. x.com