The 25G Ethernet solution is a solution standardized and developed by the IEEE 802.3 working group P802.3by. This solution is mainly used in the data center environment. The 25G Ethernet Alliance was established in July 2014 to support the deployment of single-channel 25GB/s solutions and dual-channel 50GB/s Ethernet solutions. The 25GB Ethernet Alliance was completed in September 2015. In November 2015, the 802.3 working group was established to develop a single-channel 25 GB/s Ethernet solution. On June 30, the IEEE 802.3by standard was approved by the IEEE-SA Standards Committee.

The FiberWDM 802.3by standard defines the following technologies:

Single channel 25 GB/s 25GBASE-KR PHY for printed circuit backplanes. PHY is a chip, an abbreviation for the physical layer of the OSI model；

Single channel 25 GB/s 25GBASE-CR-S PHY for 3 m twinaxial cable (in-rack) Single channel 25 GB/s 25GBASE-CR-L PHY for 5 m twinaxial cable (between racks) ；

Single channel 25 GB/s for 100 m OM4 or 70 m OM3 multimode fiber

25GBASE-SR PHY

25GB Ethernet equipment has been purchased on the market since June 2016, and it uses SFP28 and QSFP28 optical transceivers. In addition, direct connection SFP28 to SFP28 cables with fixed lengths of 1, 2, 3, and 5 meters are also available. These are made by different manufacturers. In addition, an optical transceiver supporting 1310 nanometer "LR" optical devices was recently announced, which will be able to reach 2 kilometers to 10 kilometers through two strands of single-mode fiber.

There are several factors for successfully creating a fully functional 25GB Ethernet. Optical transceivers and direct cables supporting 25GB and 50GB Ethernet are necessary. At the end of the connection, the NIC card that must support these solutions will guarantee the highest performance. The deployment of 25GB Ethernet solutions in the data center will certainly promote the entire core network, storage network and cloud computing network, so as to use 10GB Ethernet solutions to provide customers with greater bandwidth and stability.

The SFP28 optical transceiver is a transceiver based on the popular SFP+ form factor that introduces a new generation of high-density 25 GB/s Ethernet applications for data centers and enterprise companies. It provides a traditional and cost-effective upgrade.