What is SFP?
A SFP is a hot-swappable input/output device that plugs into the SFP ports, linking the switch with the fiber-optic network.
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. Superseding the GBIC transceiver, SFP modules are also called "mini-GBIC" due to their smaller size. By choosing the appropriate SFP module, the same electrical port on the switch can connect to fibers of different types (multimode or singlemode) and different wavelengths. If the fiber is upgraded, the SFP module is replaced.
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.
A few characteristics of SFP
Communications standards: SFP can be made to support multiple communications standards, such as fiber channel (FC), Gigabit Ethernet, synchronous optical networking and synchronous digital hierarchy (SONET/SDH). They are most often used for Fast Ethernet or Gigabit Ethernet.
Data transmission speed: SFP typically supports data transfer speeds of up to 4.25 gigabits per second (Gbit/s).
Predominance: SFP makes up the majority of transceivers in the market today.