2022年10月13日星期四

What is 25G SFP28 Optical Transceiver Module

 The data rate of optical modules has upgraded from 100 Mbps to 1 Gbps to 10G, 25G, 100G and even 400G for development of fiber optic communication. Among them, SFP28 transceiver module is an optical module with a transmission rate of 25Gbps. SFP28 stands for small form-factor pluggable 28. It features low power consumption, high port density and can save the cost of network deployment, so it is widely used in 25G Ethernet and 100G (4X25Gbps) Ethernet.

Advantages of 25G SFP28 Transceiver Modules

1. Compared with 100G optical modules, SFP28 modules have lower loss.

2. Compared with 40G optical modules, SFP28 modules are more cost-effective. SFP28 modules can adopt two fiber channels to achieve 50G transmission rate, while 40G modules need four 10G fiber channels to achieve 40G transmission rate

3. Compared with 10G optical modules, SFP28 modules have 2.5 times the optical input/output performance that of 10G modules, and feature higher port density, thus can save operating costs by reducing the number of ToR switches and cable.

Categories of 25G SFP28 Modules

There are mainly 2 types, SFP28-25G-SR, and SFP28-25G-LR.

SFP28-25G-SR

They are compliant with IEEE 802.3, SFF-8472, SFF-8402, SFF-8432, SFF-8431 and other standards. It is an SFP28 optical module with center wavelength of 850nm, supporting DOM (Digital Optical Monitoring) function to help manage the real-time monitoring of optical modules. Its difference from other SFP28 optical modules lies in its transmitter type - VCSEL (vertical-cavity surface-emitting laser), so it requires the use of 50/125µm MMF OM3/OM4 patch cables. The SFP28-25G-SR modules are sui for short-distance data transmission (max. 100m) and can be used in 25G Ethernet switches, routers, network interface cards (NIC) and storage network devices.

SFP28-25G-LR

They are also compliant with IEEE 802.3, SFF-8472, SFF-8402, SFF-8432, SFF-8431 and other standards. It is an SFP28 optical module with center wavelength of 1310nm, and its maximum transmission distance can reach up to 10km being used together with single mode fiber, therefore SFP-25G-LR modules are mainly used in long distance transmission (max. 10km). Its difference from SFP-25G-SR modules lies in that it uses DFB laser transmitter.