The QSFP28 LR4 is a hot-pluggable, four-channel, and full-duplex optical transceiver module designed for long-distance transmission up to 10 km in the 100G Ethernet network with a working bandwidth of 1295nm to 1310nm. The FS® 100GBASE Quad Small Form-Factor Pluggable (QSFP28) portfolio offers customers a wide variety of high-density and low-power 100 Gigabit Ethernet connectivity options for data center, high-performance computing networks, enterprise core and distribution layers, and service provider. 100G QSFP28 is a hot-pluggable optical transceiver form factor designed to deliver 100-gigabit Ethernet connectivity using four parallel 25-gigabit lanes. It is widely used in data centers, enterprise core networks, and telecom infrastructure due to its high port density, standardized interface. The QSFP28 (Quad Small Form-Factor Pluggable 28) transceiver is a compact optical module designed for high-speed data communication at 100 Gbit/s. The “28” designation refers to the 28 Gbps electrical signaling speed per channel. It is the essential component that enables flexible, scalable connectivity across switches, routers, and servers. More importantly, it provides the bridge for the 100G upgrade path, allowing interoperability with.