The SFP28 optical module is an optical module with a transmission rate of 25 Gbps.It has the advantages of low power consumption, high port density, and save network deployment cost. The SFP28 optical transceivers are designed for use in 25G/28G data network over Single 
mode fiber or multimode fiber. The fiber transceivers complied with IEEE 802.3, SFF-8472 Rev 12.2, IEEE-8402,SFF-8432 and portions of SFF-8431 Rev.4.1. The 25G SFP28 Transceivers featured with small size for improving port density, reliable connecting, and low power consumption, it is idea Data Centers, 5G Network, HPC, 25G Ethernet and Fiber Channel.
Product specifications:
The QSFP28 optical module uses multi-channel transmissions such as 100GbE and 128GFC with multiple package interfaces (4+4 MPO and dual-core LC).
The SFP28 optical module, also known as the 25G SFP28 optical module, is an optical module with a transmission rate of 25 Gbps, mainly used in 25G Ethernet and 100G Ethernet.
Advantages of the SFP28 optical module：
- Compared to 10G optical modules, the SFP28 optical module has 2.5 times the optimal input/output performance and fiber capacity. With higher port density, it can save operating costs by reducing the number of ToR switches and cables.
- Compared with the 40G optical module, the SFP28 optical module costs less, because the SFP28 optical module can use two fiber channels to achieve 50G transmission rate, and the 40G optical module needs to achieve 40G transmission rate through four 10G fiber channels.
- The SFP28 optical module has less loss than the 100G optical module.
Classification of SFP28 optical modules：
The SFP28 optical module is mainly divided into two types: SFP-25G-SR optical module and SFP-25G-LR optical module. The specific details are as follows:
- SFP-25G-SR optical module
The SFP-25G-SR optical module complies with multiple standards and specifications such as IEEE 802.3, SFF-8472, SFF-8402, SFF-8432, and SFF-8431. It is an SFP28 optical module 
with a center wavelength of 850 nm and supports DOM (Digital Optics). The monitoring function helps the network management to monitor the information of the optical module in real time. Unlike other SFP28 optical modules, the SFP-25G-SR light is caused by the internal cavity of the SFP-25G-SR optical module. The module needs to be used with OM3/OM4 multimode fiber with a fiber diameter of 50/125μm. The SFP-25G-SR optical module is suitable for short-distance data transmission (the maximum transmission distance is 100m), and can be applied to short-distance data transmission in switches, routers, network interface cards (NICs) and storage network devices of 25G Ethernet. .
- SFP-25G-LR optical module
The SFP-25G-LR optical module is also compliant with multiple standards. It is an SFP28 
optical module with a center wavelength of 1310 nm. When the optical fiber is used together, the transmission distance can reach 10km. Therefore, the SFP-25G-LR optical module is mainly used for long-distance data transmission (the maximum transmission distance can be up to 10km), and it is different from the SFP-25G-SR optical module by the SFP. The -25G-LR optical module uses a DFB laser.
