SFP ETYMOLOGY
The fiber optic market is filled with variety of products , SFP  otherwise called “mini-GBIC” due to their smaller size is a hot-pluggable, compact transceivers used for both communication applications and telecommunications. SFP transceivers are designed to support SONET, Gigabit Ethernet, Fibre Channel, and other communications standards. Due to their similarities and its smaller size, The SFP modules convert serial electrical signals to serial optical signals and vice versa. The form factor and electrical interface are specified by a multi-source agreement (MSA).

SFP port accepts both optical modules and copper cables. 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.
there are different types of transceivers namely; ( GBIC, SFP, SFP+, QSFP, X2, CFP ) etc. 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.

 Types of SFP Module?

SFP transceiver module comes in various types on the basis of different classification standards. There are single mode SFP module and multimode SFP module according to the cable type, which allows users to select the appropriate transceiver according to the required optical range for the network. And the transmission rate of SFP module is available from 100Mbps up to 4Gbps or more. Working distance of these SFP transceiver modules can be from 500 meters to 100 kilometers. CWDM SFP module and DWDM SFP modules are also available for WDM links. In addition, copper SFP module allows communications over twisted pair networking cables. Here is a simple classification of SFP modules.The following table is a simple classification of SFP modules. The chart below represents types of SFP module available.

SFP Types Transceiver Type Connector Distance Data Rate
SFP Fiber Module SX, MX, LX, EX, ZX, EZX, BX LC Duplex 100m-160km over MMF or SMF 100Mbps/
1000Mbps
CWDM/DWDM SFP LC Duplex 10km-120km over SMF
 

SFP Copper Module

1000BASE-T
RJ45
100m over Copper Twist Pair Cable
1000Mbps
10/100BASE-T
RJ45
100m over Copper Twist Pair Cable
100Mbps
0/100/1000BASE-T
RJ45
100m over Copper Twist Pair Cable
1000MbpsUsually, SFP ports are found in Ethernet switches, routers, firewalls and NIC cards. SFP modules connect a network device to a fiber or copper network cables like Cat5e. And other types of SFP optical transceivers like 3G video SFP, 12G video SFP  are also used in HD camera or monitoring systems