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Pluralistic SFP Connector Family 1

Author:danny / time:2020-12-17 / The number of clicks:7372

In the previous articles, we have had a simple understanding of the development and evolution of SFP connectors and GBIC connectors, and compared their characteristics and differences. However, SFP connectors are actually divided into several different types, so today we want to have a deeper understanding of the application of SFP connectors and matters needing attention during use.

Classification and Application of SFP Connectors
SFP connectors are generally used in optical fiber network communication transmission, so SFP optical modules are generally used in routers, switches, optical transceivers and base stations. SFP connectors is half the previous generation of product GBIC, which is of a small size, light weight and has excellent performance. SFP modules are divided into single-mode optical fibers and multi-mode optical fibers. In order to facilitate the distinction, manufacturers will color the pull rings during manufacturing to distinguish SFP single-mode and SFP multi-mode. The following table will briefly compare the differences between the two:


SFP single-mode

SFP multi-mode

Transmission distance

Above 2KM

Below 2KM

Wave length



Pull ring color

Blue, yellow, purple





Equipment application

It can be applied to single-mode optical fiber and multi-mode optical fiber

It can be applied to multi-mode optical fiber

Current trend

SFP has become the mainstream because its single-mode performance is much better than that of the multi-mode type


SFP and BiDi SFP Modules
General SFP modules have a TX port and RX port. The TX port is used to transmit signals and the RX port is used to receive signals, which means two optical fiber connections will be required. However, there is another BiDi SFP module. BiDi is an abbreviation of bidirectional, also known as single-first bidirectional optical module. It has only one port and uses an integrated WDM coupler to transmit and receive signals. Only one optical fiber is needed to transmit optical signals in both directions.

Can SFP optical modules be connected to other optical modules?
In short, to connect the two optical modules, you need the same wave length and transmission distance (parameters), for example, both 20km and 1310nm, so you can communicate directly.

Where there are optical fibers, there must be optical modules. The popularity of modern optical fiber networks and communications makes SFP connectors very flexible and widely used. In the next article, we will further discuss other functions and differences in SFP optical modules.