Fiber Optics Industry Leaders Announce Collaboration To Define A New Multicore Fiber Design Optimized For AI Data Center Campuses

America Fujikura Ltd. (AFL), Corning Incorporated, Sumitomo Electric Industries, Ltd., and TeraHop PTE. LTD., today announced a collaboration to develop a new Multi-Source Agreement (MSA^*¹) called the “SDM4 MCF MSA,” that outlines the critical four-core multicore fiber design, performance, and interoperability requirements for passive optical connections in data center applications.

As AI network scale-out^*² creates an unprecedented demand for higher density optical infrastructure and traditional single-core fiber solutions approach their practical limitations, the industry, including hyperscalers, is turning to new technologies like multicore fiber that can deliver more capacity and connectivity within the same physical infrastructure.

This collaboration aims to define the operating procedures, scope, technical requirements, and other terms of the SDM4 MCF MSA to facilitate multicore fiber adoption across diverse environments, such as intra-campus networks and other short-reach interconnect applications operating in the O-band^*³. It can also serve as a foundation and help accelerate development of new global technology and information standards in standardization bodies, including the International Telecommunication Union Telecommunication Standardization Sector (ITU-T), International Electrotechnical Commission (IEC), and Institute of Electrical and Electronics Engineers (IEEE), associated with multicore fiber solutions.

Members of the MSA intend to finalize and publicly release the initial SDM4 MCF Specification in the coming months in concert with leading hyperscaler(s) support. Additional MSA members will be welcomed after the initial release to support ongoing multicore fiber ecosystem development and market adoption.

^*1 MSA: an industry-defined, multi-vendor agreement that establishes common technical and interoperability requirements—typically documented in an MSA specification—so that products and components from different suppliers can work together.

^*2 AI scale-out: the horizontal expansion of AI infrastructure by adding more servers, racks, or GPUs so workloads can run across larger multi-node clusters, increasing demands on network interconnects.

^*3 O-band: the ‘original’ optical transmission band, typically 1260–1360 nm and centered around 1310 nm, commonly used for short-reach optical links because chromatic dispersion is low near this wavelength.