The SFP transceivers are available with a variety of transmitter and receiver types, the user can select the appropriate transceiver for each link to provide the necessary optical reach over the available optical fiber type (multimode fiber or single mode fiber).
The SFP modules are generally classified into several basic types:
a) For multi-mode fiber
SX - 850 nm, for distances up to 550 m (1.25 Gb/s) or 150m(4.25 Gb/s )
b) For single-mode fiber
LX - 1310 nm, for distances up to 10 km
BX - 1490 nm/1310 nm, SFP BiDi Transceivers, also for distances up to 10 km
1550 nm 40 km (XD), 80 km (ZX), 120 km (EX or EZX)
CWDM SFP and DWDM SFP transceivers at various wavelengths achieving various maximum distances
c) For copper twisted pair cabling
1000BASE-T - incorporate significant interface circuitry and can be used for Gigabit Ethernet only, as that is the interface they implement. They are not compatible with (or rather: do not have equivalents for) Fiber channel or SONET.