Keep 100 GbE links open across distances that strain standard short-reach optics. This QSFP28 transceiver is designed for 100G 4WDM operation over single-mode fiber, with a 40 km reach that fits campus interconnects, metro edge links, and distributed data center designs where fiber plant already exists. The LC connector simplifies integration into established single-mode infrastructure, while the QSFP28 form factor supports high-density switch and router platforms that need more bandwidth per rack unit. For teams planning around growth, the value is not just speed — it is preserving link budget and operational headroom on runs where lower-cost optics would force compromises in distance or topology. Use this module when you need to extend 100 GbE without redesigning the network around a different transport architecture. It is a practical fit for backbone extensions, building-to-building connectivity, and aggregation paths where reach matters as much as throughput.