UALink – Ultra Accelerator Link – Open-Source/Hardware Alternative to NVLink (en.wikipedia.org)

The Ultra Accelerator Link (UALink), a groundbreaking open specification for die-to-die interconnectivity between AI accelerators, has been announced by an impressive consortium of tech giants, including Alibaba, AMD, Apple, and Google. Launched in 2024, UALink's initial version (1.0) supports a staggering 200 Gbps bandwidth and is designed for scalability within AI "pods." Each node consists of a host and multiple accelerators, managed by a unified operating system and connected via various interconnect protocols such as CXL and PCIe. The UALink Switch can connect up to 1,024 accelerators while assigning each a unique 10-bit routing identifier, establishing a novel standard for AI-specific interconnect architecture. This initiative is particularly significant for the AI/ML community as it presents a compelling open-source alternative to existing proprietary solutions like NVIDIA's NVLink, potentially democratizing access to advanced accelerator technology. By fostering collaboration among major industry players, UALink aims to streamline interconnectivity in AI systems, enhancing performance and scalability. The UALink specification will be available for public evaluation, encouraging broader participation in the development of advanced AI infrastructure. This could pave the way for more efficient and versatile AI applications, strengthening the ecosystem's overall capability.