SFP (Small Form-factor Pluggable) is a small transceiver
that plugs into the SFP port of a network switch and connects to
fibre channel and gigabit Ethernet (GbE) optical fiber cables at
the other end. The SFP converts the serial electrical signals to
serial optical signals and vice versa. SFP modules are hot swappable
and contain ID and system information for the switch.