Build a Four-Endpoint Multimode 200G Optical Branch Plan

Overview

A documented NVIDIA configuration connects a twin-port switch optic to four 200G endpoints by using both optical ports in splitter mode. This is a useful design pattern when a rack needs several lower-rate adapter or DPU links while retaining a twin-port switch-side optic. It is a manufacturer application pattern, not a claim about an installed SwitchInfra customer system. Begin with the switch-side role. MMA4Z00-NS is a finned OSFP, multimode 2xSR4 transceiver with two independent 400G optical ports. Each port can be paired with a 1:2 multimode fiber splitter. One MFP7E20-N010 assembly serves one optical port; two assemblies are needed for four branches. The selected assemblies are 10 m long, with OM3 fiber and female MPO/APC interfaces. At the far ends, use the separately specified compatible single-port optical engines in the actual adapter or DPU cage. NVIDIA distinguishes ConnectX-7 OSFP endpoints from QSFP112 ConnectX-7 or BlueField-3 endpoints. The splitter only exposes two optical channels to each destination, creating the documented 200G operating arrangement with the compatible transceiver configuration. Keep the two switch-side optical paths consistent. The MMA4Z00-NS overview says both must be straight or both must be split; a mixed arrangement is not supported there. Label the two parent optical ports and all four branch destinations. Record the port mode, fiber route, optic identity and expected logical rate before insertion. Review the total optical path rather than assuming cable length is the complete reach budget. Patch-panel junctions, mating cleanliness, fiber grade and connector polish affect the link. The 30 m OM3 and 50 m OM4 product reach figures belong to the optic; they do not change the selected 10 m assembly into a longer cable. Finally, check the actual firmware-specific reach limit and test all four links. Retain the completed port map for service, while keeping any New and Used hardware offerings commercially separate. Scope: Original engineering article based on manufacturer manuals; no fabricated deployment result or owned-customer success claim.