Cisco SFP SX is a type of small form-factor pluggable (SFP) transceiver used for fiber-optic communication. It is designed to support Gigabit Ethernet and Fiber Channel applications. It is compatible with Cisco switches and routers and is available in a variety of wavelengths, including 850nm, 1310nm, and 1550nm. It is also available in a variety of distances, ranging from 550m to 10km. Cisco SFP SX is a cost-effective solution for high-speed fiber-optic communication. It is reliable, easy to install, and provides superior performance.