While everyone is focusing on GPUs and optical modules, DCI (Data Center Interconnect) is becoming one of the fastest-growing and most certain tracks in AI infrastructure.

After the explosion in demand for logical AI computing power, data centers at the east and west ends of a city are no longer operating independently—they need to integrate computing resources for token processing. To use an analogy, it's like independent restaurants that used to operate separately are now becoming a central kitchen distribution system, requiring high-speed interconnection between data centers.

This interconnection is what the DCI backbone transmission system does. It brings incremental growth at several levels:

First, the DCI system equipment itself—including the mainframe chassis, optical amplifier plug-in boards, data aggregation and distribution boards, WSS, optical switches, and a series of other components. Note that this does not include switches; it is a transmission system independent of the internal data center network.

Second, coherent optical modules—this is the component with the highest value share in DCI equipment. Key data: The cost share of optical modules in DCI systems has surged from 30-40% in the first half of 2025 to 60-70%. The reason is that, driven by AI, new DCI systems tend to fill all module slots and maintain additional inventory.

Third, EDFA (Erbium-Doped Fiber Amplifier) and upstream pump chips—EDFAs are in severe shortage. The quantity of EDFAs required for delivery by Ciena and Nokia has doubled, with monthly demand increasing from 10,000 units to 15,000-20,000 units.

DCI has formed a telecom-side industry chain parallel to the internal data center optical modules (sold by InnoLight and Eoptolink to NVIDIA and Google). I divide it into three layers:

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