Best Practices for 400G ConnectX®-7 NIC and Switch Interconnection via RoCE/InfiniBand
May 12, 20251 min read
Network capacity is constantly being challenged by the exponential growth of data, applications, and mobility. Every new user, every emerging AI workload, and every latency-sensitive application demands more bandwidth, more agility, and higher efficiency from the data center infrastructure.
To keep pace, modern data centers must adopt scalable, high-throughput solutions. Enterprises and cloud providers alike are moving toward 400G solution and beyond, seeking not just raw speed but network infrastructures that offer operational agility, visibility, and resilience at scale.
Advantages of Deploying 400G NICs in Data Centers
With increasing network bandwidth demands and server processing capabilities, 400G NICs have become essential components in today’s high-bandwidth data centers. The latest SmartNICs offer either two 25G/50G/100G/200G ports or a single 400G OSFP/QSFP112 port, featuring 50G PAM4 SeDes capabilities and PCIe 4.0/5.0 x16 host connections. SmartNICs play a vital role in enhancing network programmability and accelerating application offloading, helping data centers meet the current and future demands of high-bandwidth, high-density environments.
FS’s ConnectX®-7 400G network adapter portfolio offers one of the industry’s most advanced, high-performance platforms designed to meet the rigorous demands of AI, HPC, and cloud environments. The OSFP NICs support both InfiniBand and Ethernet protocols to enable flexible deployment and exceptional throughput. These solutions are engineered to maximize end-to-end performance, enhance energy efficiency, and strengthen network security—empowering enterprises to build agile, scalable, and cost-optimized infrastructures ready for the future.
FS 400G ConnectX®-7 Connectivity Scenarios
Featuring both InfiniBand and Ethernet solutions, FS offers versatile 400G solution options powered by NVIDIA® ConnectX®-7. These scenarios support a wide range of high-performance networking needs—whether for ultra-low-latency HPC workloads or scalable AI data centers—helping customers build flexible, future-ready infrastructures.
Infiniband Connectivity Solutions
800G OSFP Switch to 2x 400G OSFP NIC
This solution uses an 800G switch and NVIDIA® ConnectX®-7 400G NICs for efficient 2x400G breakout. Each 800G port connects to two 400G NICs via twin-port transceivers and short-reach fiber supporting up to 50m or DACs.
Switch Specification | Switch-Side Modules | Fiber Cables | Adapter-Side Modules | Adapter Specification |
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Ethernet Connectivity Solutions
800G OSFP Switch to 2x 400G OSFP NIC
Achieve dual 400G connectivity from each 800G switch port using breakout cables or fiber, linking to NVIDIA® 400G NICs. Fiber cables can link to 400G transceiver up to 50-meters, ideal for high-speed GPU server interconnects.
Switch Specification | Switch-Side Modules | Fiber Cables | Adapter-Side Modules | Adapter Specification |
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400G QSFP-DD Switch to 400G OSFP NIC
This 400G direct link connects a 400G switch to an 400G NIC via multimode fiber and SR4 modules. A QSFP-DD transceiver on the switch pairs with an OSFP module on the NIC using an MTP® OM4 cable, enabling 400G connectivity up to 50m with multimode fiber.
Switch Specification | Switch-Side Modules | Fiber Cables | Adapter-Side Modules | Adapter Specification |
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Conclusion
With the rise of 400G switches and the continuous pursuit of higher bandwidth and lower latency, ConnectX®-7-based 400G interconnect solutions have become a key driver in the evolution of data center networks. By supporting flexible deployment modes—such as 800G-to-2x400G and 400G-to-400G —ConnectX®-7 provides enterprises with the performance and versatility needed for high-performance computing, cloud infrastructure, and AI clusters.
At FS, we’re not just delivering faster connections—we’re enabling future-ready, high-speed solutions that scale with your business. From core switching to server access, our end-to-end offerings help customers unlock the performance and efficiency needed for today’s demands and tomorrow’s growth. Explore now!