MSA-compliant 200G QSFP56 and QSFP-DD transceivers for AI/ML clusters and hyperscale data center aggregation. PAM4, SR4 and LR4 variants. Made in Taiwan by Coretek Opto.
200G transceivers bridge the gap between the established 100G tier and the emerging 400G infrastructure. The primary form factors are QSFP56 (4×50G PAM4 lanes) and QSFP-DD (Dual Density, capable of 200G in 2×100G or 4×50G configuration). QSFP56 maintains mechanical backward compatibility with QSFP28 cages, operating at 100G in those ports. QSFP-DD is a larger form factor — QSFP-DD cages accept QSFP28 modules, but QSFP-DD modules require a QSFP-DD cage.
What is QSFP56? QSFP56 uses the same QSFP housing as QSFP28 and QSFP+ but drives each of the four electrical lanes at 50 Gbps using PAM4 modulation, achieving 200 Gbps total. Are 200G transceivers compatible with 100G switches? In QSFP56-capable cages the module negotiates at 200G. In QSFP28 cages, some switch platforms may operate the module at 100G — verify backward compatibility with your switch vendor before ordering.
Reach options for 200G include SR4 (multimode, up to 100 m on OM4) and LR4 (10 km on single-mode). QSFP-DD at 200G supports the same physical reach as QSFP56 while also serving as a migration path toward 400G with a simple optic swap.
200G is used in hyperscale data center aggregation layers, high-performance AI and machine learning cluster interconnects, and as an intermediate upgrade step for operators moving from 100G to 400G infrastructure. For teams building GPU clusters for AI/ML training, 200G NICs and switches from Mellanox/NVIDIA and Intel often require QSFP56 or QSFP-DD 200G optics for node-to-node spine connectivity.