Differences Between BiDi SFP and SFP


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What Is BiDi SFP Optical Transceiver

BiDi SFP uses WDM (Wavelength Division Multiplexing) Bi-Directional transmission technology to send and receive different central wavelengths in two directions, and realize simultaneous Bi-Directional data transmission on one optical fiber.

The BiDi SFP has only one LC interface, which transmits and receives optical signals on one optical fiber through an integrated bidirectional coupler.

Therefore, we use single-fiber BiDi SFP optical modules in pairs.

Note: The description including Bi-Directional, BiDi, single fiber, single core, WDM, BX-U, BX-D, etc. refers to BiDi SFP optical transceivers.

How Does BiDi SFP Optical Transceiver Work

The main difference between the BiDi SFP optical module and the ordinary SFP optical module is that the BiDi SFP optical module has a built-in wavelength division multiplexing (WDM) coupler, also called a duplexer, which combines and separates the data transmitted on one optical fiber according to different wavelengths.

In order to work efficiently, BiDi SFP optical modules must be used in pairs. By tuning the duplexer to match the desired wavelengths of the transmitter and receiver, the operating wavelengths of the two duplexers must be complementary and identical to achieve Bi-Directional data transmission.

For example, in one pair of 1G BIDI SFP 20KM optical modules, if one side wavelength is Tx-1310nm/Rx-1550nm, another side should be Tx-1550nm/Rx-1310nm. If one side wavelength is Tx-1310nm/Rx-1490nm, another side should be Tx-1490nm/Rx-1310nm. Please note that Tx-1310nm/Rx-1550nm cannot connect with Tx-1490nm/Rx-1310nm.

BIDI SFP Optical Transceivers Applications

BiDi SFP optical modules are usually used in ISP, FTTX, data centers, fiber-to-the-home deployment P2P (point-to-point) connections, and other networks with 1/10/25/50Gbps transmission rate. BiDi SFP optical modules can be installed in switches, fiber optic transceivers, OEO converters, and other equipment to provide high-speed and stable optical transmission.

  1. For direct connection to switches. A pair of BiDi SFP optical modules are respectively installed on the switches at both ends, and the two BiDi SFP optical modules are connected with LC simplex jumpers to build a link.
  2. For connecting fiber converters. A pair of BiDi SFP optical modules are respectively inserted into the fiber converters at both ends and connected by a single-mode jumper. At the same time, users use network cables to connect switches and fiber converters. In this way, Ethernet-fiber transmission can be realized
  3. Used to connect OEO converter. A pair of BiDi SFP optical modules are respectively deployed on the OEO converters at both ends to realize multi-mode-single-mode transmission

The BiDi SFP optical module only needs one fiber, which saves fiber resources and is a better choice for users with insufficient fiber resources.

Ordinary optical modules require 2 optical fibers, but the price is cheaper than single-fiber BiDi SFP optical modules. If the optical fiber resources are sufficient, you can choose ordinary optical modules.

Differences Between BiDi SFP and SFP Optical Transceivers

  1. BiDi SFP optical module adopts WDM technology, which is not used by ordinary optical modules;
  2. BiDi SFP optical modules need to be used in pairs, and ordinary optical modules do not;
  3. BiDi SFP optical module structure has a light splitter and a light combiner, but ordinary modules do not
  4. BiDi SFP optical module only needs one optical fiber, and the ordinary optical module needs two
  5. BiDi SFP optical modules are more expensive than ordinary optical modules
  6. BiDi SFP optical module has only one interface, and ordinary module has two interfaces

Features of BiDi SFP Optical Transceivers

BiDi SFP optical modules can save fiber resources, and the reduction of fibers can reduce the cost of fiber optic cabling infrastructure. BiDi SFP optical modules can reduce the number of ports on the fiber jumper panel, optimize the space occupied by the tray dedicated to fiber management, and reduce the number of optical cables.

Although the price of BiDi SFP optical modules is higher than that of ordinary optical modules, they use half the number of optical fibers per unit transmission distance. For many networks, the cost savings of fewer fibers far outweighs the relatively high purchase price of common optical modules

Aerech BiDi SFP Optical Transceivers Types


10G BiDi SFP+

10G BiDi XFP

25G BiDi SFP28


BiDi SFP optical modules can support high-bandwidth, low-latency, and high-reliability data transmission, and effectively save fiber resources. It is a practical solution to help users simplify network wiring and increase network capacity. At the same time, the high-speed 25/50G BiDi optical module can provide faster and more stable data transmission for 5G networks, and is a high-quality choice for 5G network deployment. And BiDi dual-fiber Bi-Directional optical module has great potential.