400G OSFP & OSFP112 Optical Transceivers

400G OSFP and OSFP112 transceivers deliver 400 Gigabit Ethernet connectivity in the OSFP form factor, built for data center spine-leaf fabrics, campus backbones, and metro links. Both variants share the same cage and the same optics. The difference sits entirely on the host side, in how many electrical lanes the module expects from the connected switch or NIC.

OSFP modules use a 400GAUI-8 electrical interface: eight lanes at 53.125 Gbps PAM4, converted by an internal gearbox to four 100G-class optical lanes. These suit host platforms built on 50G-class SerDes. OSFP112 modules use 400GAUI-4: four lanes at 106.25 Gbps PAM4 mapped one-to-one onto four optical lanes with no gearbox, for platforms built on 100G-class SerDes. Because the optical side is identical, an OSFP DR4 and an OSFP112 DR4 can interoperate across the fiber when the PMD and link parameters match at both ends. The form factor choice is dictated by what the host equipment presents electrically, not by what sits at the far end of the link.

Our portfolio spans the full range of reach requirements. Short-reach VR4 and SR4 modules handle intra-rack connections over multi-mode fiber at 50m and 100m, while DR4 and DR4+ variants extend parallel single-mode connectivity to 500 meters and 2km. For cross-building and metro links, FR4 and LR4 modules provide CWDM4-based transmission reaching 2km and 10km respectively.

The OSFP112 modules in this range use a flat-top (RHS) design, relying on a riding heat sink integrated into the host cage, while the OSFP modules are finned-top and cool through their own fin stack. Some cages accept only one style, so confirm the exact port specification before ordering.

All modules support DDM/DOM diagnostics and comply with OSFP MSA standards. Confirm the electrical interface and heatsink variant the platform expects before ordering. The module reports the same identifier for the finned-top and flat-top heatsink variants, so it will not flag a heatsink mismatch on its own.