The SFP optical module (small form-factor pluggable) is a standardized interface for transmitting data in a computer network. It can support multiple protocols and rates, such as gigabit Ethernet, fiber channels and sonet.
Passive devices refer to terminal node devices without power lines and built-in batteries, such as some sensors. These devices require the action of an external signal to produce an electrical signal output.
Active equipment refers to electronic components with a power supply inside, which can actively input and output electrical signals, such as computers and mobile phones.
According to the above definition, the SFP optical module is not a simple device, but a component with composite functions. This means that some SFP optical modules are passive and some are active.
For passive SFP optical modules, its basic function is to convert electrical signals into optical signals for long-distance transmission without additional energy input. This method is called "straight-through" and is suitable for simple optical cable connections or short-distance transmission.
For active SFP optical modules, they include a transmitting laser or led, which generates optical signals through battery or line input energy, and then changes and shapes the signal to supplement it, and finally transmits it to the designated place to achieve high quality and high-speed data transmission. This method is called "non-straight-through" and is suitable for long-distance or high-speed transmission.
Therefore, the question of whether the SFP optical module is passive or active cannot be simply answered, and the detailed explanation mentioned above must be supplemented. Need to choose different SFP according to the specific situation.