Last week, Cisco introduced the 51.2T Cisco 8223 router P200 deep-buffer routing silicon, purpose-built for enabling AI clusters with hundreds of thousands of GPUs to scale-across multiple data centers. While scale-across is the new frontier for connecting the largest AI training workloads, scale-up remains the critical enabler for ultra-high bandwidth communication between AI compute nodes. 

Cisco is proud to continue our efforts to accelerate scale-up connectivity as an initial member of the Open Compute Project’s (OCP) Ethernet for Scale-Up Networking (ESUN) collaboration. The ESUN collaboration, which launched today at the OCP Global Summit 2025, marks an important step forward in advancing Ethernet technology to meet the unique demands of scale-up networking.  

AI workloads are re-shaping modern data center architectures, and networking solutions must evolve to meet the growing demands. ESUN brings together AI infrastructure operators and vendors to align on open standards, incorporate best practices, and accelerate innovation in Ethernet solutions for scale-up networking. ESUN will focus solely on open, standards-based Ethernet switching and framing for scale-up networking—excluding host-side stacks, non-Ethernet protocols, application-layer solutions, and proprietary technologies. 

Cisco is Committed to Open, Interoperable AI Networking  

Cisco’s participation in ESUN reflects our commitment to open, interoperable, and high-performance AI networking at scale. We believe Ethernet is the foundation for scale-up networks, and that open collaboration is the best path to accelerate adoption. Cisco will continue to play a role in a range of industry standards bodies that are working towards this goal. With ESUN, we look forward to furthering our partnerships and industry leadership to drive open innovation. 

Cisco’s initial priorities for the collaboration include: 

• Optimizing open industry standards for Ethernet-based scale-up solutions;  
• Promoting interoperability of XPU networking interfaces and Silicon One-based Ethernet switches; 
• And defining efficient L2/L3 headers for switching, error recovery and enabling  lossless, low latency scale-up interconnectivity. 

By collaborating with other ecosystem partners across hardware and software, Cisco and ESUN aim to advance Ethernet-based scale-up networking across the industry for rapid adoption. We look forward to working with the ESUN OCP membership to shape the future of scale-up networking!