The industry-standard Cisco® Small Form-Factor Pluggable (SFP) Gigabit Interface Converter is a hot-swappable input/output device that plugs into a Gigabit Ethernet port or slot, linking the port with the network (Figure 1). SFPs can be used and interchanged on a wide variety of Cisco products and can be intermixed in combinations of 1000BASE-SX, 1000BASE-LX/LH, 1000BASE-ZX, or 1000BASE-BX10-D/U on a port-by-port basis. 1000BASE-LX/LH SFP for Both Multimode and Single-Mode Fibers The 100BASE-LX/LH SFP, compatible with the IEEE 802.3z 1000BASE-LX standard, operates on standard single-mode fiber-optic link spans of up to 10 km and up to 550 m on any multimode fibers.