An SFP is a compact, hot-pluggable network interface module used for both telecommunication and data communications applications. An SFP interface on networking hardware is a modular slot for a media-specific transceiver in order to connect a fiber-optic cable or sometimes a copper cable. The SFP replaced the larger gigabit interface converter (GBIC) in most applications, and has been referred to as a Mini-GBIC by some manufacturers.
SFPs allow individual ports to be equipped with any suitable type of transceiver as needed
SFP transceivers support Gigabit Ethernet, Fibre Channel, PON, and other communications standards
SFPs can have any connector from RJ45 to LC to MTP