AI infrastructure is exploding beyond single-server boundaries. As models grow and workloads demand tightly synchronized communication across larger accelerator pools, local PCIe, CXL, and proprietary interconnects are no longer sufficient as the primary scale-up mechanism. They remain important within the server, but can create constrained compute islands across accelerator generations, system designs, and vendors. Operators are moving toward rack-scale scale-up domains, interconnecting tens to hundreds of XPUs across enclosures with high-bandwidth, low-latency links to operate as a single, tightly coupled supercomputing instance.
Expanding scale-up domains to hundreds of XPUs fundamentally shifts connectivity demands and creates a new compute+network-centric paradigm. The network is no longer simply the fabric between servers; it becomes part of the compute system itself. Just as Ethernet has become the leading open foundation for AI scale-out fabrics, the industry is now advancing Ethernet-based scale-up solutions for performance, openness, interoperability, and ecosystem choice.
Evolution from Server I/O → Rack-Scale
Recognizing the critical need for an open scale-up ecosystem, Arista galvanized the Ethernet for Scale-Up Networks (ESUN) initiative within OCP as a founding member alongside industry leaders such as Broadcom, Meta, and Microsoft. ESUN is focused on open Ethernet switching and framing for tightly coupled AI fabrics, including lossless delivery, error resiliency, and scale.
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Arista NetworksArista Networks is an industry leader in data-driven, client to cloud networking for large data center/AI, campus and routing environments. Arista’s award-winning platforms deliver availability, agility, automation, analytics and security through an advanced network operating stack Arista was founded by industry luminaries Andy Bechtolsheim, Ken Duda and David Cheriton, launched in 2008 and is led by CEO Jayshree Ullal. Its seasoned leadership team is globally recognized as respected leaders and visionaries with a rich and extensive history in networking and innovation. The company went public in June 2014, is listed with NYSE (ANET), and currently has more than 10,000+ cloud customers worldwide and has deployed 100M ports.
