Tech Giants Unite to Replace Copper with Light in AI Data Centres

The Copper Wall

The biggest names in artificial intelligence have joined forces to tackle one of the industry's most pressing physical challenges: the wiring inside data centres is running out of road. AMD, Broadcom, Nvidia, Meta, Microsoft, and OpenAI announced the formation of the Optical Compute Interconnect Multi-Source Agreement group on Thursday, a consortium that will define an open specification for replacing copper cables with optical interconnects in AI scale-up systems.

Why Light Beats Wire

As AI models grow larger, the clusters of processors that train them need to exchange data at extraordinary speeds. Copper interconnects, which have served the industry for decades, are hitting fundamental physical limits. At current data rates, passive copper cables can barely span a single server rack before signal quality degrades, and the energy needed to push electrical signals further now accounts for a significant share of total data centre power consumption. Optical connections solve both problems: light can travel farther with less energy and more predictable performance.

The Specification

The OCI MSA specification uses a combination of non-return-to-zero modulation and wavelength division multiplexing to carry data over fibre. The first generation supports two hundred gigabits per second in each direction, with a roadmap that scales to three point two terabits per second per fibre in future iterations. The design supports pluggable, on-board, and co-packaged optics, giving system builders flexibility in how they adopt the technology.

Competitors Working Together

The consortium is remarkable for uniting fierce rivals. Nvidia's proprietary NVLink dominates high-end GPU clusters, while AMD and Broadcom back the open-standard UALink effort. The OCI MSA operates at the optical physical layer, meaning it could underpin both NVLink and UALink traffic over fibre rather than copper. The announcement arrives ahead of the Optical Fiber Communications Conference in Los Angeles, where the optical interconnect market for AI data centres is projected to grow from roughly ten billion dollars to over thirty billion dollars by twenty thirty-three.