The Introduction of SFP Modules

Even though we cannot see the fiber optical communications products frequently in daily life, our life is closely related to them. In fiber optical communications field, fiber optic transceiver module is widely used by high-speed communication systems. And as the indispensable part of transceiver module, SFP (Small Form-Factor Pluggable) have gained much attention around the world.

The SFP is a compact, hot-pluggable transceiver used for both telecommunication and data communications applications, which are designed to support SONET, gigabit Ethernet, Fiber Channel, and other communications standards. SFP now can reach 4G at the highest and often use the LC interface. Because of its smaller size, SFP can be configured more than double of ports on the same panel. Moreover, most functions of SFP are the same as GBIC (Gigabit Interface Converter). So the SFP is sometimes referred to as a Mini-GBIC although no device with this name has ever been defined in the MSAs.

There are many kinds of SFP modules according to different transmitter and receiver types, allowing users to select the appropriate transceiver for each link to provide the required optical reach over the available optical fiber type, such as multi-mode fiber or single-mode fiber. Optical SFP modules are commonly available in these categories.

SX - 850 nm, for a maximum of 550 m at 1.25 Gbit/s (gigabit Ethernet) or 150m at 4.25 Gbit/s (Fibre Channel),with multi-mode fiber
LX - 1310 nm, for distances up to 10 km, with single-mode fiber
EX - 1310 nm, for distances up to 40 km, with single-mode fiber
ZX - 1550 nm, for distances up to 80 km, with green extraction lever (see GLC-ZX-SM1),with single-mode fiber
EZX 1550 nm, for distances up to 160 km, with single-mode fiber
TX：Electrical Modules，for distances up to 100m
CWDM：Coarse Wavelength Division Multiplexing
DWDM：Dense WaveLength Division Multiplexing
BX - 1490 nm/1310 nm, Single Fiber Bi-Directional Gigabit SFP Transceivers, paired as BS-U and BS-D for Uplink and Downlink respectively, also for distances up to 10 km. Variations of bidirectional SFPs are also manufactured which use 1550 nm in one direction.

Due to the important role SFP modules played in the fiber optical communication field, many scientific companies have paid much more attention to the SFP. Because of its hot-pluggable function, SFP modules can be connected or cut by the equipment without cutting the power. And this function also makes it possible for the administrator to upgrade or extend the system without affecting the users online. Moreover, the SFP modules make the maintaining work more simple. Meanwhile, because of the heat exchanging function of SFP, we can make the overall plan for the cost of sending and receiving, link distance, and all the network topology according to the network upgrading demand, instead of changing all the system board.

Through the above introduction, you will know what SFP module is, the different types of it and the main functions of SFP module. Nowadays the SFP optical module has become the most frequently used fiber optical transceiver module in the fiber communications industry. And the prospects of it has also been widely noticed by fiber optical communications field.