You can find SX, LX, LHX, ZX and ZHX compatible SFPs in this category with distances up to 120Km, but also 155M, 622M or multi-rate 2. 5G and 4G SFPs, used in SONET, SDH or Fibre Channel networks. The industry-standard Cisco Small Form-Factor Pluggable (SFP) Gigabit Interface Converter (Figure 1) links your switches and routers to the network. The hot-swappable input/output device plugs into a Gigabit Ethernet port or slot. These mini-GBIC (Gigabit Interface Converter) modules come in a metal housing that reduces electromagnetic interference and increases their. SFP optical transceivers are most used optical interface in telecommunications these days. This category has most common multi-mode and single-mode versions but also covers long-haul options.